\documentclass[10pt,a4paper]{article} % Packages \usepackage{fancyhdr} % For header and footer \usepackage{multicol} % Allows multicols in tables \usepackage{tabularx} % Intelligent column widths \usepackage{tabulary} % Used in header and footer \usepackage{hhline} % Border under tables \usepackage{graphicx} % For images \usepackage{xcolor} % For hex colours %\usepackage[utf8x]{inputenc} % For unicode character support \usepackage[T1]{fontenc} % Without this we get weird character replacements \usepackage{colortbl} % For coloured tables \usepackage{setspace} % For line height \usepackage{lastpage} % Needed for total page number \usepackage{seqsplit} % Splits long words. %\usepackage{opensans} % Can't make this work so far. Shame. Would be lovely. \usepackage[normalem]{ulem} % For underlining links % Most of the following are not required for the majority % of cheat sheets but are needed for some symbol support. \usepackage{amsmath} % Symbols \usepackage{MnSymbol} % Symbols \usepackage{wasysym} % Symbols %\usepackage[english,german,french,spanish,italian]{babel} % Languages % Document Info \author{seashore} \pdfinfo{ /Title (cna.pdf) /Creator (Cheatography) /Author (seashore) /Subject (CNA Cheat Sheet) } % Lengths and widths \addtolength{\textwidth}{6cm} \addtolength{\textheight}{-1cm} \addtolength{\hoffset}{-3cm} \addtolength{\voffset}{-2cm} \setlength{\tabcolsep}{0.2cm} % Space between columns \setlength{\headsep}{-12pt} % Reduce space between header and content \setlength{\headheight}{85pt} % If less, LaTeX automatically increases it \renewcommand{\footrulewidth}{0pt} % Remove footer line \renewcommand{\headrulewidth}{0pt} % Remove header line \renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit % This two commands together give roughly % the right line height in the tables \renewcommand{\arraystretch}{1.3} \onehalfspacing % Commands \newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour \newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols \newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns \newcommand{\tn}{\tabularnewline} % Required as custom column type in use % Font and Colours \definecolor{HeadBackground}{HTML}{333333} \definecolor{FootBackground}{HTML}{666666} \definecolor{TextColor}{HTML}{333333} \definecolor{DarkBackground}{HTML}{1CD2FF} \definecolor{LightBackground}{HTML}{E1F9FF} \renewcommand{\familydefault}{\sfdefault} \color{TextColor} % Header and Footer \pagestyle{fancy} \fancyhead{} % Set header to blank \fancyfoot{} % Set footer to blank \fancyhead[L]{ \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{C} \SetRowColor{DarkBackground} \vspace{-7pt} {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}} } \end{tabulary} \columnbreak \begin{tabulary}{11cm}{L} \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{CNA Cheat Sheet}}}} \\ \normalsize{by \textcolor{DarkBackground}{seashore} via \textcolor{DarkBackground}{\uline{cheatography.com/31325/cs/10378/}}} \end{tabulary} \end{multicols}} \fancyfoot[L]{ \footnotesize \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{LL} \SetRowColor{FootBackground} \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}} \\ \vspace{-2pt}seashore \\ \uline{cheatography.com/seashore} \\ \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}} \\ \vspace{-2pt}Not Yet Published.\\ Updated 5th February, 2017.\\ Page {\thepage} of \pageref{LastPage}. \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}} \\ \SetRowColor{white} \vspace{-5pt} %\includegraphics[width=48px,height=48px]{dave.jpeg} Measure your website readability!\\ www.readability-score.com \end{tabulary} \end{multicols}} \begin{document} \raggedright \raggedcolumns % Set font size to small. Switch to any value % from this page to resize cheat sheet text: % www.emerson.emory.edu/services/latex/latex_169.html \footnotesize % Small font. \begin{multicols*}{3} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{PSTN}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483485412_Screen Shot 01-03-17 at 07.03 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN Overview}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SIP devices communicate across an IP network connection such as the Internet to the Proxy at their ITSP} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{When the ITSP needs to direct calls to the PSTN, it forwards the calls to a SIP/ PSTN gateway that converts the signaling and voice media to the format the PSTN is expecting} \tn % Row Count 7 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call flow}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483487160_Screen Shot 01-03-17 at 07.45 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call flow}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SIP device dials the number of a PSTN device} \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The proxy sends the INVITE on to the SIP/PSTN gateway that will in turn send the appropriate SETUP message to the PSTN switch and onto the telephone} \tn % Row Count 4 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{A provisional acknowledgement - 183 - informs the SIP device of the progress of the call setup and setup an early media channel} \tn % Row Count 7 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Once the phone starts ringing, the 'alerting' and '180 ringing' messages are sent back to the SIP device} \tn % Row Count 10 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{When answered, the 'answer' and '200' messages are answered} \tn % Row Count 12 (+ 2) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The media stream starts to flow after the SIP device sent it acknowledgements} \tn % Row Count 14 (+ 2) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The gateway convert RTP media to TDM media for the PSTN and vice versa} \tn % Row Count 16 (+ 2) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Both proxy and gateway can be used ambiguous depending on where they're being used and by whom, but ... A proxy generally talks SIP only (i.e. on both sides), and acts as a router for inbound and outbound requests (just like a web proxy). This might be required for security, NAT traversal or other reasons.} \tn % Row Count 23 (+ 7) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{A gateway generally talks something other than SIP as well, such as a PSTN gateway which allows calls to and from the public switched telephone network which is based on TDM protocols such as ISDN or SS7.} \tn % Row Count 28 (+ 5) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{PSTN to SIP call flow}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483490441_Screen Shot 01-03-17 at 08.40 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.24425 cm} x{3.73275 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{PSTN to SIP call flow}} \tn % Row 0 \SetRowColor{LightBackground} ACM & alerting \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} REL no answer & Release no answer \tn % Row Count 3 (+ 2) % Row 2 \SetRowColor{LightBackground} RLC & release complete \tn % Row Count 4 (+ 1) % Row 3 \SetRowColor{white} CPG & alerting, Call Progress (CPG) messages \tn % Row Count 6 (+ 2) % Row 4 \SetRowColor{LightBackground} ANM & answer \tn % Row Count 7 (+ 1) % Row 5 \SetRowColor{white} PRACK & provisional acknowledgement \tn % Row Count 8 (+ 1) % Row 6 \SetRowColor{LightBackground} ISUP & Integrated services digital network user part \tn % Row Count 10 (+ 2) % Row 7 \SetRowColor{white} IAM & Initial address message \tn % Row Count 11 (+ 1) % Row 8 \SetRowColor{LightBackground} NPI & numbering plan indicator, eg E.164 \tn % Row Count 13 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call failure}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483531780_Screen Shot 01-04-17 at 08.06 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{If a SIP device tries to call a PSTN phone and there is no answer, a Release No answer message is returned to the SIP gateway from the PSTN switch which acknowledges with a Release complete message. A 480 temporarily unavailable message is sent to the SIP device.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483532658_Screen Shot 01-04-17 at 08.24 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483532719_Screen Shot 01-04-17 at 08.25 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The proxy sent a 407 forbidden message that ask for Authentication from the SIP UA} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483532792_Screen Shot 01-04-17 at 08.26 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483532856_Screen Shot 01-04-17 at 08.27 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483532956_Screen Shot 01-04-17 at 08.29 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483533016_Screen Shot 01-04-17 at 08.29 AM 001.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483533148_Screen Shot 01-04-17 at 08.32 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to PSTN call trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483533246_Screen Shot 01-04-17 at 08.33 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Early Media}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{To overcome a few problems that arise due to two different systems such as SIP and the PSTN trying to work together, a concept called Early Media has been introduced} \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Early media is not required on standard PSTN calls as when a number is dialed a media channel is established so the caller can hear the ringing tone of the remote device.} \tn % Row Count 8 (+ 4) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Early media gives companies the opportunity to replace ringing media with corporate messages or other instructions for the caller before they speak to a real person} \tn % Row Count 12 (+ 4) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Clipping is a problem where if a person using a PSTN phone answers their phone and starts talking straight away, without Early Media the SIP phone that is calling them will miss the first part of the converstation as it hasn't yet received a 200 OK message to enable it to set up the RTP media path.} \tn % Row Count 18 (+ 6) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Early media also allow busy tone and other announcements to be played to the caller even though the called phone has not been picked up.} \tn % Row Count 21 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Early Offer}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483623169_Screen Shot 01-05-17 at 09.29 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Early offer - the calling SIP device send an INVITE with the SDP body that includes contact info and a range of codecs that the SIP device supports. The receiving SIP device can then select a codec to use from the list offered, usually, the nearest one to the top and then the call is setup.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Delayed Offer}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483624325_Screen Shot 01-05-17 at 09.46 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Maybe used in SIP trunk scenarios - the PBX sends an INVITE without an SDP body to the ITSP. The ITSP may only want the PBX to use the G.729 codec, si it lists only that codec in the 200OK. The PBX has only one choice and will then use G.729 for media across the SIP trunk.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Mini Quizlet}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{If you see a 407 error 'returned' from a Proxy Server to a SIP UA, what is the Proxy asking the SIP UA for ?} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}The proxy sent a 407 forbidden message that ask for Authentication from the SIP UA} \tn % Row Count 5 (+ 5) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Default Gateway}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483625086_Screen Shot 01-05-17 at 09.46 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{A customer's default gateway is actually a default router.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Gateway}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483625495_Screen Shot 01-05-17 at 09.46 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The SIP/PSTN gateway to the PSTN is to provide signalling and media conversion between the SIP and PSTN networks. When the SIP/SDP messages hit the signaling gateway it converts it to ISDN/ISUP signalling for the PSTN. RTP/RTCP media and control packets hit the media gateway for conversion to TDM for the PSTN \newline A single server may be running Gateway, proxy, location, registration services on it} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{TRIP - Gateway location and routing with TRIP}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{TRIP or telephony routing over IP intends to make it easy to find telephone number destinations and is achieved by using location servers that can advertise to each other their knowledge of gateways and the telephone numbers that these gateways support.} \tn % Row Count 6 (+ 6) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{TRIP is protocol independent in that it can be used not only with SIP but also other protocols such as H.323} \tn % Row Count 9 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Gateways advertise their PSTN number range to a Location server, using TRIP protocol, that then advertises this range to other location servers.} \tn % Row Count 12 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The gateway tells the Location server of the numbers or routes that they can get to and their own contact details} \tn % Row Count 15 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The Location servers then use Inter-domain routing updates to converge this info around to the other LS servers.} \tn % Row Count 18 (+ 3) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{When a SIP client calls a number in another part of the world, the INVITE goes to the proxy. The Proxy may use ENUM to see if the number has a SIP location. If not, the Proxy forwards the SIP INVITE to the gateway. The gateway will check with the Location server to see which is the best Gateway to breakout to the PSTN. The Location server looks at its table and returns the relevan info to the Gateway. This then contacts the gateway at the remote end and the call is setup via that local gateway} \tn % Row Count 29 (+ 11) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{TRIP is an emerging protocol that promises to do for SIP what BGP did for the internet in making it easy for SIP calls to be connected to most appropriate Gateway} \tn % Row Count 33 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Mini Quizlet}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{TRIP can help make it easy for gateways to find other gateways on a network thus enabling on-net communications. What does the R in TRIP stands for?} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}routing} \tn % Row Count 4 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP-T SIP for telephones}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SIP-T is a framework that can enable SIP networks to carry legacy telephone signals across an IP based network to another legacy network.} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The legacy SS7 ISUP messages have to be interrogated by the SIP/PSTN gatway and then the info that will help SIP proxies to route the SIP message is built into the SIP header while other ISUP info is added as a MIME message body. This message can be encrypted.} \tn % Row Count 9 (+ 6) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SIP INFO is another SIP-T approach or method that is used for in-call ISUP signaling across an IP network} \tn % Row Count 12 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{SIP-I (SIP with encapsulated ISUP) was developed by the ITU, not the IETF for SIP-T. It is more accurate than SIP-T} \tn % Row Count 15 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SS7}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483631349_Screen Shot 01-05-17 at 11.48 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SS7, signalling system 7, sets up network connections between switches within the PSTN. ISDN sets up the connections between the user part and the network boundary.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SS7, ISDN, and SIP}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483631420_Screen Shot 01-05-17 at 11.49 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP to ISUP messages}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483631529_Screen Shot 01-05-17 at 11.51 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{3.03597 cm} x{1.94103 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{SIP to ISUP messages}} \tn % Row 0 \SetRowColor{LightBackground} INVITE & IAM , setup \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} BYE & REL, release \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} CANCEL & REL, release \tn % Row Count 3 (+ 1) % Row 3 \SetRowColor{white} 180 ringing & ACM, alerting \tn % Row Count 4 (+ 1) % Row 4 \SetRowColor{LightBackground} 183 session progress & ACM, alerting \tn % Row Count 5 (+ 1) % Row 5 \SetRowColor{white} 181 forwarding & CPG, alerting \tn % Row Count 6 (+ 1) % Row 6 \SetRowColor{LightBackground} 200 response to IAM & ANM, connect \tn % Row Count 7 (+ 1) % Row 7 \SetRowColor{white} 4xx, 5xx, 6xx & REL \tn % Row Count 8 (+ 1) % Row 8 \SetRowColor{LightBackground} 200 response to BYE & RLC \tn % Row Count 9 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.58804 cm} x{2.38896 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{ISDN User part (ISUP) to SIP mapping}} \tn % Row 0 \SetRowColor{LightBackground} {\bf{ISUP Event Code}} & {\bf{SIP Message}} \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} 1: Alerting & 180: Ringing \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} 2: Progress & 183: Session progress \tn % Row Count 4 (+ 2) % Row 3 \SetRowColor{white} 3: In-band information & 183: Session progress \tn % Row Count 6 (+ 2) % Row 4 \SetRowColor{LightBackground} 4: Call forward; Line Busy & 181: Call is being Forwarded \tn % Row Count 8 (+ 2) % Row 5 \SetRowColor{white} 5: Call forward; No Reply & 181: Call is being Forwarded \tn % Row Count 10 (+ 2) % Row 6 \SetRowColor{LightBackground} 6: Call forward; unconditional & 181: Call is being Forwarded \tn % Row Count 12 (+ 2) % Row 7 \SetRowColor{white} {\bf{ISUP Cause Code}} & {\bf{SIP Message}} \tn % Row Count 13 (+ 1) % Row 8 \SetRowColor{LightBackground} 1: Unallocated number & 404: Not Found \tn % Row Count 15 (+ 2) % Row 9 \SetRowColor{white} 2: no route to network & 404: Not Found \tn % Row Count 17 (+ 2) % Row 10 \SetRowColor{LightBackground} 17: User busy & 486: Busy here \tn % Row Count 18 (+ 1) % Row 11 \SetRowColor{white} 18: No user responding & 408: Request timeout \tn % Row Count 20 (+ 2) % Row 12 \SetRowColor{LightBackground} 21: Call rejected & 403: Forbidden \tn % Row Count 21 (+ 1) % Row 13 \SetRowColor{white} 28: Address Incomplete & 484: Address Incomplete \tn % Row Count 23 (+ 2) % Row 14 \SetRowColor{LightBackground} 34: No circuit available & 503: Service unavailable \tn % Row Count 25 (+ 2) % Row 15 \SetRowColor{white} 38: Network out of order & 502: Service unavailable \tn % Row Count 27 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{PSTN to PSTN via SIP}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483632560_Screen Shot 01-05-17 at 12.08 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{PSTN to PSTN call via SIP is also known as SIP bridging} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483633168_Screen Shot 01-05-17 at 12.08 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{INVITE} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483633589_Screen Shot 01-05-17 at 12.24 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{VIA} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483633836_Screen Shot 01-05-17 at 12.27 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{TO / FROM \newline \newline To: shows who is being called \newline From: shows the detail of the caller's telephone number} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483634032_Screen Shot 01-05-17 at 12.32 PM 001.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CSeq used to identify and order the transactions} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483633961_Screen Shot 01-05-17 at 12.32 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CALL- ID is the globally unique ID for this transaction.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483634135_Screen Shot 01-05-17 at 12.34 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CONTACT gives info on who is being called} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483634249_Screen Shot 01-05-17 at 12.36 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CONTENT-TYPE shows us that the SIP body is of the type SDP, session description protocol} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483634329_Screen Shot 01-05-17 at 12.38 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CONTENT LENGTH} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483634455_Screen Shot 01-05-17 at 12.39 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\bf{o}} shows originating Gateway} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483634603_Screen Shot 01-05-17 at 12.42 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SDP {\bf{c}} field also show originating gateway details.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ISUP encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483634946_Screen Shot 01-05-17 at 12.47 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SDP content-type - any ISUP info that cannot be mapped to SIP will be retained, and in this case secured} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Incomplete Encapsulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483635399_Screen Shot 01-05-17 at 12.53 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{unbekannt means unknown in German \newline In anonymous PSTN calls, the transaction Call-ID will help the gateway to separate this session from other anonymous calls.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{DTMF}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483635583_Screen Shot 01-05-17 at 12.58 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{DTMF - dual tone - multi frequency \newline When you press the buttons on a telephone keypad, a connection is made that generates two tone at a time, a row tone and a column tone.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Tones over a SIP/VoIP network}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483635927_Screen Shot 01-05-17 at 01.05 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{DTMF tones} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Tones over a SIP/VoIP network}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483636002_Screen Shot 01-05-17 at 01.06 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Fax-related tones} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Tones over a SIP/VoIP network}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483636333_Screen Shot 01-05-17 at 01.12 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Standard subscriber line tones} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Tones over a SIP/VoIP network}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483636163_Screen Shot 01-05-17 at 01.08 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Country-specific subscriber line tones} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Tones over a SIP/VoIP network}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1483636237_Screen Shot 01-05-17 at 01.10 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Trunk events} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.69218 cm} x{3.28482 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{DTMF Transport methods}} \tn % Row 0 \SetRowColor{LightBackground} Inband & DTMF is transmitted in the same RTP stream as the media is. \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} & Some tones will be heard by parties in the conversation \tn % Row Count 6 (+ 3) % Row 2 \SetRowColor{LightBackground} & Only works when using G.711 codec or better. Compression codecs such as G.729, G723 may make tones unintelligible. \tn % Row Count 11 (+ 5) % Row 3 \SetRowColor{white} Out of band RFC 2833 & Is an out of band method that takes DTMF out of the RTP stream and into its own RTP packets. \tn % Row Count 15 (+ 4) % Row 4 \SetRowColor{LightBackground} & DTMF codes can survive ok even if the main stream is compressed. \tn % Row Count 18 (+ 3) % Row 5 \SetRowColor{white} & The out of band RTP packets hold the various event codes and the tone is regenerated by an appropriate gateway or SIP UA \tn % Row Count 23 (+ 5) % Row 6 \SetRowColor{LightBackground} RFC 4733 & build on and supersedes RFC 2833 \tn % Row Count 25 (+ 2) % Row 7 \SetRowColor{white} & Requires that devices don't have to support every tone and event there is, just advertise what they do support when setting up a connection. \tn % Row Count 31 (+ 6) \end{tabularx} \par\addvspace{1.3em} \vfill \columnbreak \begin{tabularx}{5.377cm}{x{1.69218 cm} x{3.28482 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{DTMF Transport methods (cont)}} \tn % Row 8 \SetRowColor{LightBackground} RFC 4734 & updates 4733 with more event codes for modem, fax, and text telephony signals that get carried in the RTP payload \tn % Row Count 5 (+ 5) % Row 9 \SetRowColor{white} SIP INFO & method is used to carry session control info along the SIP signaling path during an existing session. \tn % Row Count 9 (+ 4) % Row 10 \SetRowColor{LightBackground} & SIP proxies can see and act upon SIP INFO messages and not DTMF Inband or RFC 2833 packets. \tn % Row Count 13 (+ 4) % Row 11 \SetRowColor{white} & Eg- a phone call to a bank, the session is established but you may get asked to type in an account number. SIP INFO carries the digits you type without changing the characteristics of the SIP session. RFC 6086 \tn % Row Count 22 (+ 9) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Module Quiz}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The main purpose of a PSTN Gateway is to provide signaling and media translation services between SIP and the PSTN} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}True} \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Which SIP method is used to carrying 'in-call' ISUP signaling acress an IP network} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}INFO} \tn % Row Count 7 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Signaling paths}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{An} \tn % Row Count 1 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Voice over IP}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{In a VoIP system, all calls run over a shared network, this is known as packet switching. All voice calls are converted from analog signals to digital ones and transmitted over the network just like other data from PCs and servers.} \tn % Row Count 5 (+ 5) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Main transport protocols - TCP and UDP} \tn % Row Count 6 (+ 1) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{TCP - transmission control protocol breaks data into packets, lebel them and send them out in order. On receipt the destination will acknowledge arrival. If an acknowledgment is not received within a set time data is resent. This guarentees delivery but can slow thing down a little} \tn % Row Count 12 (+ 6) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{UDP - user datagram protocol is used to carry voice. There are no acknowledgements and no resends. This is the protocol of choice for real time applications such as video and voice.} \tn % Row Count 16 (+ 4) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SIP RFC 3261 - all SIP elements must implement UDP and TCP. SIP elements may implement other protocols.} \tn % Row Count 19 (+ 3) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{UDP is becoming obsolete because a lot of SIP products now produce headers that are too big for UDP. TCP is being used more because it has the ability to break up messages, re-assemble them at the destination and cope with packet loss with retransmissions.} \tn % Row Count 25 (+ 6) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Microsoft's Skype for Business only support TCP for signaling.} \tn % Row Count 27 (+ 2) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Layer 5 Session - SIP messages} \tn % Row Count 28 (+ 1) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Layer 4 Transport - TCP segments} \tn % Row Count 29 (+ 1) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{TCP segments has a maximum segment size of 1500 bytes.} \tn % Row Count 31 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Signaling paths}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484568583_Screen Shot 01-16-17 at 08.08 AM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Signaling paths}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{An IP PBX consists of a call server/ manager that controls the calls} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Usually the network supporting all the components of ah IP PBX is an Ethernet LAN. In some cases, the components can be remotely located over a WAN} \tn % Row Count 5 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{An access gateway is needed for supporting legacy phones, fax machines and other analog devices} \tn % Row Count 7 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Trunk gateway are useful for connecting to the PSTN/POTS network.} \tn % Row Count 9 (+ 2) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{IP phones and softphones connect directly to the LAN or WAN} \tn % Row Count 11 (+ 2) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{A router can be used to connect to other IP PBXs over an IP LAN or even SIP trunks of VoIP service} \tn % Row Count 13 (+ 2) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The calling device contacts the call server/manager which in turn the called device. This signaling path can operate with SIP or older standard H.323 or vendor's proprietary signaling protocol.} \tn % Row Count 17 (+ 4) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Signaling path does NOT carry the voice call.} \tn % Row Count 18 (+ 1) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{All components of an IP PBX use IP addresses, the call server/manager or other servers must include DHCP and DNS functions.} \tn % Row Count 21 (+ 3) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{TFTP is used to download software and configuration information to the IP phones, softphones and gateways.} \tn % Row Count 24 (+ 3) % Row 10 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{A network time protocol (NTP) server sets the time clock for all the supported VoIP devices.} \tn % Row Count 26 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Speech paths}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Once the call server/manager has determined that call call proceed, it established a peer-to-peer connection between the two endpoints, eg IP phone, softphone, gateways} \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{This connecton uses the real time protocol (RTP) to carry the voice packets between devices} \tn % Row Count 6 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The call path is a point-to-point connection bypassing the call server/ manager.} \tn % Row Count 8 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{IP PBX advantages}} \tn % Row 0 \SetRowColor{LightBackground} Single cable infrastructure & PC can connect into an IP phone and share the LAN connection \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} Flexibility in moving devices & Reconnect your phone to any other wall point and your number moves with you \tn % Row Count 7 (+ 4) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{2}{x{5.377cm}}{Integration with IP applications} \tn % Row Count 8 (+ 1) % Row 3 \SetRowColor{white} \mymulticolumn{2}{x{5.377cm}}{Integrated voicemail / auto attendant} \tn % Row Count 9 (+ 1) % Row 4 \SetRowColor{LightBackground} Integration with unified messaging systems & For speech to text and text to speech conversion \tn % Row Count 12 (+ 3) % Row 5 \SetRowColor{white} SIP trunking & ability to migrate from PSTN connectivity to SIP trunking using VoIP \tn % Row Count 16 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Encoding}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Encoding is all about taking an analogue waveform, converting it into digital information before it is sent to the intended recipient} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Encoding converts the orginal analogue signal into a binary data stream.} \tn % Row Count 5 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The encoder is set to take a reading of the wave - 8 thousand times a second, so 1 millisecond is going to be read or 'sampled' 8 times.} \tn % Row Count 8 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Digital telephony requires 64000 bits per second for normal speech quality} \tn % Row Count 10 (+ 2) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{A codec that produces binary data at a rate of 64Kbps is usually working to the G.711 specification} \tn % Row Count 12 (+ 2) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{G.711 - uncompressed voice} \tn % Row Count 13 (+ 1) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{G.729 - compressed voice (annex A/B/J)} \tn % Row Count 14 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Codecs of voice}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484582489_Screen Shot 01-16-17 at 12.00 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Codecs for voice RTP payload type}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484588059_Screen Shot 01-16-17 at 01.34 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.89126 cm} x{3.08574 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Codecs for voice}} \tn % Row 0 \SetRowColor{LightBackground} MOS - mean opinion scores & is used to get an idea of which codec sounds the best \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} MOS & is a system of grading the voice quality of telephone connections. With MOS, a wide range of listeners judge the quality of a voice sample on a scale of 1(bad) to 5(excellent). The scores are averaged to provide the MOS for the codec. \tn % Row Count 13 (+ 10) % Row 2 \SetRowColor{LightBackground} G.729 codec & compresses voice so that it is possible to use less bandwidth for each call \tn % Row Count 17 (+ 4) % Row 3 \SetRowColor{white} RTP/AVP payload type & Value that is used with the body of a SIP and SDP message in negotiation between SIP system to decide which codecs they support and are then going to use for that voice session. \tn % Row Count 25 (+ 8) % Row 4 \SetRowColor{LightBackground} Microsoft Lync & supports standard codecs. However, it has its own real time (RT) audio. \tn % Row Count 28 (+ 3) % Row 5 \SetRowColor{white} Network mean opinion & Microsoft uses a measurement called network mean opinion scores \tn % Row Count 31 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Codec test}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484590140_Screen Shot 01-16-17 at 02.08 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{HD Voice}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484591897_Screen Shot 01-16-17 at 02.21 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{G.722 samples a much larger or wider frequency range to catch depth of voice and also at the higher end. Constants such a 's' and 'f'can be hard to catch with a narrow band codec.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Wideband HD codecs}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484609602_Screen Shot 01-16-17 at 07.32 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{0.89586 cm} x{4.08114 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Wideband HD codecs}} \tn % Row 0 \SetRowColor{LightBackground} G.722 & Range from G.722 to G.722.2. Also know as adaptive multi-rate wideband \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \seqsplit{ARM-WB+} & Proliferating in many VoIp phones from companies such as Polycom, Avaya, Snom, Mitel \tn % Row Count 6 (+ 3) % Row 2 \SetRowColor{LightBackground} G.729 (J) & G.729 with annex J is now a scalable wideband codec \tn % Row Count 8 (+ 2) % Row 3 \SetRowColor{white} Speex & Popular wideband codec because of being open source \tn % Row Count 10 (+ 2) % Row 4 \SetRowColor{LightBackground} \seqsplit{RTAudio} & Microsoft owned \tn % Row Count 11 (+ 1) % Row 5 \SetRowColor{white} SILK & Skype ultra wideband codec is now available as open source \tn % Row Count 13 (+ 2) % Row 6 \SetRowColor{LightBackground} Opus & is open source and gaining in popularity. It is the preferred codec for WebRTC \tn % Row Count 16 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Opus}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Opus is a new codec for interactive speech and audio transmission over the Internet.} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{It is designed by the IETC codec working group and incorporates technology from the Skype 'Silk' codec and Xiph.org CELT codec technology} \tn % Row Count 5 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The OPUS codec is designed to handle a wide range of interactive audio applications, including Voice over IP, videoconferencing, and even remote live music performances} \tn % Row Count 9 (+ 4) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Implementing OPUS in VoIP will allow interoperability with new WebRTC enabled browsers and devices without any transcoding required} \tn % Row Count 12 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{OPUS can change bandwidth and bitrate seamlessly without any glitch} \tn % Row Count 14 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Codecs and Bandwidth}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484610529_Screen Shot 01-16-17 at 07.47 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{G.711 generates 87.2 Kbps on the network} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Codecs and Bandwidth}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484610622_Screen Shot 01-16-17 at 07.48 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{G.729 generates 31.2 Kbps on the network} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Packet Rates / packets per second}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484610753_Screen Shot 01-16-17 at 07.51 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Packet Rates / packets per second}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Codecs are responsible for breaking up the voice stream into chucks for packaging in RTP packets. The size of these chunks is know as Packet Rate} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Most installations use packet rate or size of 20ms for the voice or video element when sending a stream of data} \tn % Row Count 6 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{You sometime have the option of selecting a different rate, ie 30ms. The effect of increasing this size of the voice/video element is clear as it increases the size of the overall packet. This means that less packets will be required to deliver the same amount of data to the recipient.} \tn % Row Count 12 (+ 6) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Reducing the packet rate means that less work needs to be done on routers when it comes to analyzing IP addresses, checking QoS settings. It does also mans that packet loss can be more apparent to users as there is more information in a larger packet which if lost, results in a larger gap in a voice stream.} \tn % Row Count 19 (+ 7) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{If you are using a codec such as OPUS, you may see in Wireshark traces that the packet sizes vary from pakcet to packet. This is because the codec is adapting to network conditions. This is known as variable bit-rate codec} \tn % Row Count 24 (+ 5) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{RTP}} \tn % Row 0 \SetRowColor{LightBackground} RTP & is designed to support real-time traffic such as voice and video that is time sensitive \tn % Row Count 5 (+ 5) % Row 1 \SetRowColor{white} & It can work with both Unicast and Multicast applications \tn % Row Count 8 (+ 3) % Row 2 \SetRowColor{LightBackground} It provides services that include info such as & Payload type identications \tn % Row Count 11 (+ 3) % Row 3 \SetRowColor{white} & Sequence numbering \tn % Row Count 12 (+ 1) % Row 4 \SetRowColor{LightBackground} & Timestamps \tn % Row Count 13 (+ 1) % Row 5 \SetRowColor{white} & Delivery information \tn % Row Count 14 (+ 1) % Row 6 \SetRowColor{LightBackground} RTP & runs over UDP because TCP is not good for real time operation \tn % Row Count 18 (+ 4) % Row 7 \SetRowColor{white} RTP & does not provide any service that guarantees timely delivery of the payload \tn % Row Count 22 (+ 4) % Row 8 \SetRowColor{LightBackground} & does not provide any quality of service guarantees \tn % Row Count 25 (+ 3) % Row 9 \SetRowColor{white} & does rely on other protocols to provide these extra services \tn % Row Count 28 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RTP Encapulation}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484680055_Screen Shot 01-17-17 at 03.07 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.9908 cm} x{2.9862 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{RTP Encapsulation}} \tn % Row 0 \SetRowColor{LightBackground} RTP & orginally designed to support video conferences with multiple, geopraphically dispersed participants and is now commonly used in Internet telephony applications \tn % Row Count 7 (+ 7) % Row 1 \SetRowColor{white} & does not guarantee real-time delivery of multimedia data since this is dependent on network characteristics. \tn % Row Count 12 (+ 5) % Row 2 \SetRowColor{LightBackground} & provide infomation that receiving devices can utilize in recontructing data received. \tn % Row Count 16 (+ 4) % Row 3 \SetRowColor{white} & Information in the RTP header tells the receiver how to reconstuct the data and describes which codecs are being used along with the very useful timestamp and sequence number \tn % Row Count 24 (+ 8) % Row 4 \SetRowColor{LightBackground} Layer routing - layer 4 \& 5 & RTP is sent to UDP \tn % Row Count 26 (+ 2) % Row 5 \SetRowColor{white} Layer 3 & Then IP for addressing \tn % Row Count 27 (+ 1) % Row 6 \SetRowColor{LightBackground} Layer 1 and 2 & Then Ethernet layer for more addressing before being sent out onto the network \tn % Row Count 31 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RTP header trace}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1484681364_Screen Shot 01-17-17 at 03.29 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RTP Header Trace}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Layer 5 protocol RTP} \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The first two bits of the RTP header donate the version of RTP. ie version 2} \tn % Row Count 3 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The next bit donotes is there is padding at the end of the payload. Sometimes padding is needed in order for things like encryption to work} \tn % Row Count 6 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The next bit is the extension bit. If it is enabled then RTP header is followed by one extra header extension} \tn % Row Count 9 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The next 4 bits are used to denote how many contributing sources there are. Useful for mixers at the receiving end if multiple streams of RTP are arriving. Usually set to 0 in a single VoIP call} \tn % Row Count 13 (+ 4) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The next bit is the marker bit which is used when events such as DTMF tones, volumes and other states that will effect the RTP stream need to be carried in the payload. eg 911 call} \tn % Row Count 17 (+ 4) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The 7 bits denote the paylad type, the type of codec being used. ie G.711 type 8} \tn % Row Count 19 (+ 2) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The sequence number is used by the receiving device to detect if there is any packet loss and to put received packets in order. The initial value in a session is random and for each RTP packet it is incremented by one.} \tn % Row Count 24 (+ 5) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The timestamp is used to place the received audio in the correct timing order. A timestamp initial value is random and in the case of G.711, 20ms x 8kHz = 160 sampling instances per RTP packet. eg. the timestamp will increment by 160 for each RTP packet. In this stream, the next RTP header will show 54352} \tn % Row Count 31 (+ 7) \end{tabularx} \par\addvspace{1.3em} \vfill \columnbreak \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RTP Header Trace (cont)}} \tn % Row 9 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{32 bits are used to identify the synchronization source. It is a random value with the intention that no two synchronization sources within the same RTP session will enven have the same SSRC id.} \tn % Row Count 4 (+ 4) % Row 10 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Payload of the encoded voice element} \tn % Row Count 5 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Real Time control protocol}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The real time control protocol (RTCP) can be used alongside RTP in order to provide informaiton on the session and participants} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{RTCP carries an ID for a device that is transmitting the RTP data and this is called a canonical name of CNAME, alias. If the synchronization source changes, such as when another stream is beingin introduced from the same device or machine, the CNAME remains the same. This helps to identify participants in a session and is useful as these participants can join and leave sessions dynamically} \tn % Row Count 11 (+ 8) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{RTCP XR is a VoIP managment protocol that defines a set of metrics that contain information for assessing VoIP call quality and diagnosing problems.} \tn % Row Count 14 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{RTCP XR is used defined in RFC 3411} \tn % Row Count 15 (+ 1) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{RTCP XR messages containing key call-quality related metrics are exchanged periodically between IP phones and gateways and this allows analyzing equipment to monitor these metrics to assist in call quality analysis and troubleshooting} \tn % Row Count 20 (+ 5) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The protocol measures VoIP call quality using these following key metrics:} \tn % Row Count 22 (+ 2) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{1. Packet loss and discard rate and the distribution of lost and discarded packets} \tn % Row Count 24 (+ 2) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{2. Round-trip delay} \tn % Row Count 25 (+ 1) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{3. Signal, noise and echo levels} \tn % Row Count 26 (+ 1) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{4. Call quality in terms of estimated R factor or mean opinion score (MOS)} \tn % Row Count 28 (+ 2) % Row 10 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{5. Configuration data such as jitter buffer size and configuration, and the type of packet loss concealment algorithm in use.} \tn % Row Count 31 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Real Time Control Protocol}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Real Time Control Protocol (RTCP) can be used alongside RTP in order to provide information on the session and the participants} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Types of RTCP packet are:} \tn % Row Count 4 (+ 1) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SR- this is the sender report. Showing statistics on transmission and reception for the participants in the session that are actively sending data} \tn % Row Count 7 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{RR- this is the receiver report and it shows the reception statistics from participants that are not actively sending data in the session} \tn % Row Count 10 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SDES - the source description items including identifying information such as CNAME and allows the binding of an SSCR value with an actual id of the user.} \tn % Row Count 14 (+ 4) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{GOODBYE - this indicates end of participation in a session} \tn % Row Count 16 (+ 2) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{APP - this denotes Application specific functions that will effect/interact with the session} \tn % Row Count 18 (+ 2) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{XR - an RTCP extension that can help provide a 'rich set' of data for voice management - if it is implemented VoIP devices} \tn % Row Count 21 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RTP / RTCP and UDP Ports}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485643233_Screen Shot 01-28-17 at 06.36 PM 001.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{RTP use dynamically allocated UDP ports to send and receive traffic across. Ex. the sending port is 30,000,, the receiving port is 40392. RTCP will use UDP ports dynamically as well, but actually resulting in the RTP port value plus 1.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{QOS quality of service}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{QoS is not a single mechanism, it can be achieved if all the elements in the network WAN provided network recognize real time communication streams and give them the treatment or priority they need in order to get to their destination on time.} \tn % Row Count 5 (+ 5) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Quizlet - quality}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The system that evaluates 'voice quality' gives you a value known as the MOS. What does the MOS stand for?} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}mean opinion score} \tn % Row Count 4 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{QoS Issues}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Within the LAN and WAN, voice quality is dependent on four components:} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Delay - one way end to end voice delay should be no more than 150ms} \tn % Row Count 4 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Delay will be different for every site dependent on the network installed.} \tn % Row Count 6 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) G.114 recommendation specifies that for good voice quality, no more than 150ms of one-way, end-to-end delay or latency should occur.} \tn % Row Count 11 (+ 5) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Most manufacturers recommend that end to end delay be no more than 200ms. Of this 200 ms up to 80ms when an IP set is connected through an IP PBX. Allowing for up to 40ms delay in the PSTN without echo cancellation leaves 80ms available for use in the customer's network.} \tn % Row Count 17 (+ 6) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{{\bf{Jitter}} - no more than 30ms} \tn % Row Count 18 (+ 1) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Packet loss} \tn % Row Count 19 (+ 1) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Bandwidth} \tn % Row Count 20 (+ 1) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Test for delay and jitter with Ping -l; eg pinng -l 218 134.199.192.1 G.711 voice frame 238 bytes} \tn % Row Count 22 (+ 2) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Network delay happens in various locations such as:} \tn % Row Count 24 (+ 2) % Row 10 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{1. Hardware delays through the network} \tn % Row Count 25 (+ 1) % Row 11 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{2. Variable delays, eg router queues} \tn % Row Count 26 (+ 1) % Row 12 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{3. transmit delays- the time to traverse network} \tn % Row Count 27 (+ 1) % Row 13 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{4. processing delay in the end devices} \tn % Row Count 28 (+ 1) % Row 14 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Jitter is the variation in delay from the expected value.} \tn % Row Count 30 (+ 2) \end{tabularx} \par\addvspace{1.3em} \vfill \columnbreak \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{QoS Issues (cont)}} \tn % Row 15 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Jitter can occur from many of the network problems that cause delay like router queues, over utilized devices, poor cablings} \tn % Row Count 3 (+ 3) % Row 16 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{IP phones are able to manage around 30ms of jitter} \tn % Row Count 4 (+ 1) % Row 17 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{A packet of data leaves a phone at exactly 20 ms intervals using G.729 an on average they arrive at the destination phone every 20 ms. A jitter buffer at the receiving end copes with irregularities of the network. This is a buffer that holds each packet just long enough to allow packets to emerge at precisely 30 millisecond intervals} \tn % Row Count 11 (+ 7) % Row 18 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Packet loss means that a voice packet was sent, lost in transit and the far end never received it. Speech quality is usually not affect if packet loss stays below 5\%} \tn % Row Count 15 (+ 4) % Row 19 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{\seqsplit{http://www.voiptroubleshooter.com/problems/jitter.html}} \tn % Row Count 17 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{General VoIP acceptance criteria}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485645778_Screen Shot 01-28-17 at 07.20 PM 001.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Green - good quality \newline Amber - caution, may need to make adjustments on the network \newline Red - poor quality} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Qos}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485646453_Screen Shot 01-28-17 at 07.29 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Voice packets reaching a LAN switch can be seperated from Data traffic by utilizing VLANs and giving priority across uplinks using layer 2 classification. \newline \newline At the router, layer 3 classification needs to be implemented to prioritize real time traffic. \newline \newline Providers use MPLS to prioritize traffic within their network.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{802.1Q - vlans}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Benefits of configuring VLANs:} \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{1. separate traffic for securitiy} \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{2. separate traffic for broadcast and traffic control} \tn % Row Count 4 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{3. separate traffic due to different characteristics, ie data and voice} \tn % Row Count 6 (+ 2) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{802.1Q VLAN tagging ensures that while a frame is within the switch infrastructure it stays within its own VLAN} \tn % Row Count 9 (+ 3) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The switch will tag the frame with a VLAN ID and priority value for its life with the switched network.} \tn % Row Count 12 (+ 3) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The priority value 802.1P value ensures that frames can get priority over less important frames when faced with interswitch, shared link.} \tn % Row Count 15 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{802.1P - L2 Classification}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Layer 2 classifications is at the output or egress port of a LAN switch.} \tn % Row Count 2 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{TOS and diffserve}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485648324_Screen Shot 01-28-17 at 08.01 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{When an IP datagram hits a router, the layer 2 classification is lost and the router has to rely on Layer 3 classification. \newline \newline Older routers only recognize the first three bits in the 'type of service' field of the IP header. Newer systems recognize 6 of the bits known as the diffserve or differentiated service code point setting.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Layer 3 classification}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Default for all differentiated service value IP datagram is 0.} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{A lot of VoIP manufacturers set their IP phones voice datagram value to 46, high priority RTP traffic} \tn % Row Count 5 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{At the router, traffic is classified based on the diffserve value. RTP traffic goes into high priority EF or expedited forwarding queue.} \tn % Row Count 8 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{DSCP with assured forwarding (AF)}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485649389_Screen Shot 01-28-17 at 08.20 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Routers use assured forwarding to identify packets for forwarding.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{DSCP with Assured Forwarding (AF)}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Class selectors are useful because even if a packet hits a router that only sees the 1st 3 bits of the DSCP string, the packet can still be classified and allocated to a queue.} \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{eg Class 4 (CS4) you see that AF41 means Assured forwarding, Class 4 with a drop precedence of 1} \tn % Row Count 6 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{1 means its the most important within its own class so packets marked with AF42 would get dropped first.} \tn % Row Count 9 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Class 4 is higher than class 3. Packets marked AF43 would take priority over packets marked AF31} \tn % Row Count 11 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Bandwidth (kbps) vs packet per second (pps)}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485651449_Screen Shot 01-28-17 at 08.52 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Extra bandwidth is not always the answer. \newline \newline Ex. the equipment cannot handle the number of packets that needs attention first. \newline \newline The top diagram shoes that data traffic consumes a lot of bandwidth in a bursty nature. VoIP traffic consumes bandwidth in a constant fashion. \newline \newline The bottom diagram shows that VoIP calls create the majority of packets on the network. The router needs to process all these packets in real time.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.83689 cm} x{2.14011 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Port assignment}} \tn % Row 0 \SetRowColor{LightBackground} HTTP & port 80 \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} RTMP (flash) & port 1935 \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} BitTorrent & port 6999 \tn % Row Count 3 (+ 1) % Row 3 \SetRowColor{white} HTTPS & port 443 \tn % Row Count 4 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Issues that can affect QoS}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{WAN router/ firewall congestion due to packet load / not enough packet handling capacity} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Bandwidth hogs causing poor VoIP quality} \tn % Row Count 3 (+ 1) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Packet loss due to cabling or poorly configured issues at T1/DSL router} \tn % Row Count 5 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Poor quality wiring network deployed over a number of years. Can cause issues such as delay, packet loss} \tn % Row Count 8 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Old firmware on IP phones. Phones sitting in warehouse, 1 or 2 versions behind.} \tn % Row Count 10 (+ 2) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{DNS performance issues. Critical for VoIP as used for call setup} \tn % Row Count 12 (+ 2) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Switch duplex mismatch. Full duplex for IP phones and inter switch connections} \tn % Row Count 14 (+ 2) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Router flaps are where constant changes in route path of a call stream results in jitter. This could be caused by traffic engineering in place for load balancing.} \tn % Row Count 18 (+ 4) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{to determine how many SIP trunks over a trunk http://voiptest.8x8.com/} \tn % Row Count 20 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Quizlet}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Using DSCP values to manage voice traffic across a network device- usually a router, is known as} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Layer 3 classification} \tn % Row Count 3 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP SDP and VoIP}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485653904_Screen Shot 01-28-17 at 09.37 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP INVITE Analysis}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{In order for RTP to work properly it needs the devices in the session to organize themselves regarding UDP ports, codec selection and other factors relating to the impending session.} \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Port 5060 is the default UDP port for SIP communication} \tn % Row Count 6 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The {\bf{sendrec}} attribute specifies that the SIP devices should start off in send and receive mode.} \tn % Row Count 8 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{SDP wireshark eg audio 20016 - media is audio and the UDP port is 20016 that the device is advertising to receive Voice or RTP packets. Another media type is video} \tn % Row Count 12 (+ 4) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SDP wireshark eg RTP/AVP 0 8 18 96 - the real time protocol / audio video profile element is included so that a device can inform a receiving device of the codecs it supports. The first listed is the default.} \tn % Row Count 17 (+ 5) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{SDP wireshark eg rtpmap:8 PCMA/8000- The rtpmap element describes a little more detail of the codecs being advertised. 8 is the G.711 Alaw codec samples at 8000Hz} \tn % Row Count 21 (+ 4) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{SDP wireshark eg rtpmap:96 telephone-event/8000 - the rtpmap is a dynamic value. It is offered as an extra stream alongside the audio stream used for telephone events - usually DTMF digits.} \tn % Row Count 25 (+ 4) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The offical format of rtpmap is {[}a=rtpmap: \textless{}payload type\textgreater{} \textless{}encoding name\textgreater{}/\textless{}clock rate\textgreater{}\{/\textless{}encoding parameters\textgreater{}} \tn % Row Count 28 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP SDP 200 OK analysis}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{200 OK is a positive message saying that all is ready to go with the session} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{eg audio 56828 - the remote SIP device advertises the UDP port that it want to receive RTP audio on.} \tn % Row Count 4 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{eg RTP/AVP 8 0 18 96 - RTP/AVP codecs are listed and 8 is the first one listed, this will be the one that is now used for this session} \tn % Row Count 7 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{8 is G.711 ALaw} \tn % Row Count 8 (+ 1) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{eg fmtp:18 annexb=no - the fmtp attribute allows parameters that are specific to a particular format to be conveyed in a way that SDP doesnt have to understand them.} \tn % Row Count 12 (+ 4) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{SDP doesn't have to understand fmtp:18 annexb=no, it simply passes the information between SIP devices and hopes that they understand.} \tn % Row Count 15 (+ 3) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{eg fmtp:96 0 -16 - fmtp-entry shows that the SIP device supports up to 16 DTMF digits. If this entry is not present it is assumed that only 15 digits are supported} \tn % Row Count 19 (+ 4) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{SIP devices do not have to send RTP packets if there is nothing to send. eg silence in a conversation} \tn % Row Count 22 (+ 3) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{eg silenceSupp:off - turning off silence suppression means that RTP packets are sent even for those silent moments. Off is also the choice is transmitting other data such as Fax over IP} \tn % Row Count 26 (+ 4) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The nortprpoxy attribute tells us if the remote SIP device is using an RTP Proxy.} \tn % Row Count 28 (+ 2) % Row 10 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{eg nortpproxy:yes - no proxy is being used.} \tn % Row Count 29 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Streaming video and video - 1 way tranmission}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{RTSP- real time streaming protocol - is the protocol used to carry video} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{RTSP runs over UDP, therefore there is not mechanism to compensate for packet loss} \tn % Row Count 4 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{RTSP at the receiving end has a large buffer what can store several seconds of video. The buffer can compensate for the IP network impairments but it will cause a startup delay in the transmission.} \tn % Row Count 8 (+ 4) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{High packet loss over 5\% can cause noticeable picture distortion. Lost packets can also affect the sound quality.} \tn % Row Count 11 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Some implementations have implemented RTSP over TCP to compensate for packet loss. This delays the transmission and makes the TCP based devices incompatible with the rest of the RTSP implementations. RTSP running over TCP will very likely be blocked by firewalls.} \tn % Row Count 17 (+ 6) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Two-way conferencing with RTP}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Video conferencing is a real time two way conversation. There cannot be a significant delay added by jitter buffers at each end of the call.} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Smaller jitter buffers will force IP network designers to keep jitter in check on the network.} \tn % Row Count 5 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Once jitter exceeds 60msec, the receiving device will probably not be able to compensate and therefore the end device will discard packets thereby affecting the video quality.} \tn % Row Count 9 (+ 4) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{A larger jitter buffer could solve the problem but add more end-to-end delay which is not acceptable.} \tn % Row Count 12 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Video codecs - H.263, H.264, H.265 licensed} \tn % Row Count 13 (+ 1) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Video codecs - VP8, VP9 free} \tn % Row Count 14 (+ 1) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Frame rates - 15fps, 30fps, 60fps} \tn % Row Count 15 (+ 1) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Resolution - standard, HD=1920x1080, ultra HD, 4K} \tn % Row Count 16 (+ 1) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Better quality usually means more bandwidth} \tn % Row Count 17 (+ 1) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{QoS tagging video is important} \tn % Row Count 18 (+ 1) % Row 10 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Video bitrate calculator - https://toolstud.io/} \tn % Row Count 19 (+ 1) % Row 11 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{m:audio for voice, eg codecs Opus, SILK} \tn % Row Count 20 (+ 1) % Row 12 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{m:video for video eg codecs offered VP8 , H263} \tn % Row Count 21 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Assured SIP (AS-SIP) services}} \tn % Row 0 \SetRowColor{LightBackground} Assured SIP services & is an open standard published by the IETF developed by a US Defense organization \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} AS-SIP & includes all the standard functions of SIP but with the added functionality of data packets being prioritized over other traffic on an netowrk \tn % Row Count 12 (+ 8) % Row 2 \SetRowColor{LightBackground} & all packets are encrypted \tn % Row Count 14 (+ 2) % Row 3 \SetRowColor{white} Service provider architecture & UA sends its calls to a proxy that takes care of all the calls for all the UAs in a particular domain. \tn % Row Count 20 (+ 6) % Row 4 \SetRowColor{LightBackground} & The proxy is acting as a servic provider and adding the specific AS-SIP features of security \tn % Row Count 25 (+ 5) % Row 5 \SetRowColor{white} & Prioritization of traffic is handled by another device called an access router \tn % Row Count 29 (+ 4) % Row 6 \SetRowColor{LightBackground} Assured SIP services & requires TLS to secure all SIP signaling and SRTP to encrypt all media. \tn % Row Count 33 (+ 4) \end{tabularx} \par\addvspace{1.3em} \vfill \columnbreak \begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Assured SIP (AS-SIP) services (cont)}} \tn % Row 7 \SetRowColor{LightBackground} Assured SIP services defines a network architecture that is & built to carry secure signalling and media within a domain or area \tn % Row Count 4 (+ 4) % Row 8 \SetRowColor{white} & with MLPP defines how important calls can get through \tn % Row Count 7 (+ 3) % Row 9 \SetRowColor{LightBackground} & using Priority - user defined /Network defined \tn % Row Count 10 (+ 3) % Row 10 \SetRowColor{white} & SIP is extended with the use of the Resource priority header \tn % Row Count 13 (+ 3) % Row 11 \SetRowColor{LightBackground} & accept priority header \tn % Row Count 15 (+ 2) % Row 12 \SetRowColor{white} & Reason header for pre-emption \tn % Row Count 17 (+ 2) % Row 13 \SetRowColor{LightBackground} & open standard \tn % Row Count 18 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Proxy and Access router functions}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\bf{Proxy functions}}} \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{processing authentication requests} \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{maintaining the state information of all existing sessions including their priority which exists on all UAs under the proxies control} \tn % Row Count 5 (+ 3) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Understanding / maintaining other services being used by the UA which might need to be taken into consideration when applying AS-SIP capabilities} \tn % Row Count 8 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Verifying originating UA is actually allowed to establish the session at the re:Precedence/priority level requested} \tn % Row Count 11 (+ 3) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Working with the access router - establish permission at the access router for it to handle the precedence marked packets from the UA} \tn % Row Count 14 (+ 3) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{When to pre-empt - deciding when to preempt the end user and sending the appropriate pre-empt messages to the other party.} \tn % Row Count 17 (+ 3) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Maintain all records of the service, whether for accounting, auditing, or other purposes.} \tn % Row Count 19 (+ 2) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\bf{Access Router under control of the proxy }}} \tn % Row Count 20 (+ 1) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Transfer packets - decides which packets are to be transported between networks or domains. If access is not granted, the access router will throw these packets away} \tn % Row Count 24 (+ 4) % Row 10 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Packets, pass or stop? - sometimes a live packet stream must be stopped. Since the assured service may not be able to rely on the UA to stop the flow, it may be necessary for the access router, under the control of the proxy, to stop carrying a particular flow of traffic.} \tn % Row Count 30 (+ 6) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{AS-SIP network Resource-priority calling}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{For resource priority to work, the Require header in the SIP message should state that resource-priority be used. eg INVITE message Require: resource-priority} \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Resource-priority header contains namespace and priority known as the r-priority values.} \tn % Row Count 6 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{eg \seqsplit{Resource-priority:dsn.flash} -the namespace is dsn, which was defined by a US government network called "the defense switched network". Within this namespace there are five priority levels defined.} \tn % Row Count 10 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.29402 cm} x{3.68298 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Namespace}} \tn % Row 0 \SetRowColor{LightBackground} DSN & Defense Switch Network \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} (lowest) & dsn.routine \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} & dsn.priority \tn % Row Count 3 (+ 1) % Row 3 \SetRowColor{white} & dsn.immediate \tn % Row Count 4 (+ 1) % Row 4 \SetRowColor{LightBackground} & dsn.flash \tn % Row Count 5 (+ 1) % Row 5 \SetRowColor{white} (highest) & dsn.flash-override \tn % Row Count 6 (+ 1) % Row 6 \SetRowColor{LightBackground} DRSN & Defense RED Switch Network \tn % Row Count 7 (+ 1) % Row 7 \SetRowColor{white} (lowest) & \seqsplit{drsn.routine.drsn.priority} \tn % Row Count 8 (+ 1) % Row 8 \SetRowColor{LightBackground} & drsn.immediate \tn % Row Count 9 (+ 1) % Row 9 \SetRowColor{white} & drsn.flash \tn % Row Count 10 (+ 1) % Row 10 \SetRowColor{LightBackground} & drsn.flash-override \tn % Row Count 11 (+ 1) % Row 11 \SetRowColor{white} (highest) & \seqsplit{drsn.flash-override-override} \tn % Row Count 12 (+ 1) % Row 12 \SetRowColor{LightBackground} q735 namespace & Commercial equivalent of the DSN namespace for Multi-level precedence and pre-emption (MLPP) \tn % Row Count 16 (+ 4) % Row 13 \SetRowColor{white} & Is used by signaling system 7 (SS7) networks based on ITU q.735.3 and thus can be mapped between IP and ISDN networks \tn % Row Count 21 (+ 5) % Row 14 \SetRowColor{LightBackground} (lowest) & q735.4 \tn % Row Count 22 (+ 1) % Row 15 \SetRowColor{white} & q735.3 \tn % Row Count 23 (+ 1) % Row 16 \SetRowColor{LightBackground} & q735.2 \tn % Row Count 24 (+ 1) % Row 17 \SetRowColor{white} & q735.1 \tn % Row Count 25 (+ 1) % Row 18 \SetRowColor{LightBackground} (highest) & q735.0 \tn % Row Count 26 (+ 1) % Row 19 \SetRowColor{white} ETS & name of the US government telecommunications service called "Government Emergency Telecommunications Service" \tn % Row Count 30 (+ 4) \end{tabularx} \par\addvspace{1.3em} \vfill \columnbreak \begin{tabularx}{5.377cm}{x{1.29402 cm} x{3.68298 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Namespace (cont)}} \tn % Row 20 \SetRowColor{LightBackground} (lowest) & ets.4 \tn % Row Count 1 (+ 1) % Row 21 \SetRowColor{white} & ets.3 \tn % Row Count 2 (+ 1) % Row 22 \SetRowColor{LightBackground} & ets.2 \tn % Row Count 3 (+ 1) % Row 23 \SetRowColor{white} & ets.1 \tn % Row Count 4 (+ 1) % Row 24 \SetRowColor{LightBackground} (highest) & ets.0 \tn % Row Count 5 (+ 1) % Row 25 \SetRowColor{white} WPS & Wireless priority service defined in GSM and other wireless technologies \tn % Row Count 8 (+ 3) % Row 26 \SetRowColor{LightBackground} (lowest) & wps.4 \tn % Row Count 9 (+ 1) % Row 27 \SetRowColor{white} & wps.3 \tn % Row Count 10 (+ 1) % Row 28 \SetRowColor{LightBackground} & wps.2 \tn % Row Count 11 (+ 1) % Row 29 \SetRowColor{white} & wps.1 \tn % Row Count 12 (+ 1) % Row 30 \SetRowColor{LightBackground} (highest) & wps.0 \tn % Row Count 13 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}--} \SetRowColor{LightBackground} \mymulticolumn{2}{x{5.377cm}}{Namespaces detailed in RFC 4412} \tn \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{200OK Accept-Resource Priority}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Response to a resource priority header} \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{200 OK message will have Accept-Resource-Priority along with the namespace and r-priority value} \tn % Row Count 3 (+ 2) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{If the called party does not support the proposed resource priority details, it can respond with a 417 unknown resource priority message with different namespace and values.} \tn % Row Count 7 (+ 4) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{eg \seqsplit{Accept-Resource-Priority:} q735.0, q.735.1, q.735.2, q.735.3, q.735.4.} \tn % Row Count 9 (+ 2) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The calling party has a choice to accept and resend a q735 value in a new INVITE or decide that it cannot or will not work outside of it's own namespace.} \tn % Row Count 13 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Reason header for pre-emption events}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485809132_Screen Shot 01-30-17 at 04.42 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Reason header can help the phone inform the user by a message or a tone that the call has been dropped. eg UA2 sends a BYE message to UA1 which includes a 'Reason' code to indicate why the call was dropped.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{AS-SIP proxy}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Proxy receives SIP messages from SIP UAs} \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{-Proxy receives message} \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{-Doesn't recognize namespace defined in message, it will ignore,drop the message} \tn % Row Count 4 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{-Does recognizes and authorized it uses the priority levels. If it does not know the namespace and the UA has been authorized it will use the priority levels in the message} \tn % Row Count 8 (+ 4) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{-Not authorized, it is ignored. If the UA is not authorized, the message is rejected.} \tn % Row Count 10 (+ 2) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{-If UA doesn't have a priority level set, the proxy can assign a default} \tn % Row Count 12 (+ 2) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{-If auth and resources are all ok and available to send the message, then the message treats as normal and sent.} \tn % Row Count 15 (+ 3) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{-If auth and resource not available- priority is utilized.} \tn % Row Count 17 (+ 2) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{-Proxy maintains state of all sessions.} \tn % Row Count 18 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{MLPP Multi-level pre-emption and precedence}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The principle of MLPP or multi-level pre-emption and precedence is that more important calls override less important calls.} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{MLPP is built as proactive system in which callers must assign a precedence level at call initiation, this precedence level cannot be changed throughout that call.} \tn % Row Count 7 (+ 4) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{If there is end to end capacity to place a call, any call may be placed at any time.} \tn % Row Count 9 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{When any trunk configuration reaches its capacity, a choice must be made as to which call can continue.} \tn % Row Count 12 (+ 3) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The system will seize the trunks or bandwidth necessary to place the more important calls by pre-empting an existing call of lower precedence to permit a higher recedence call to be placed.} \tn % Row Count 16 (+ 4) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{{\bf{The main elements of MLPP are:}} A VoIP implementation of an MLPP service must provide these characteristics.} \tn % Row Count 19 (+ 3) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\bf{Call admission/pre-emption policy.}} If a call is in place with lower priority than a newer call, it must make way for the newer call, it must make way for the new call according to the policy/procedures defined for the network.} \tn % Row Count 24 (+ 5) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{All callers that have been pre-empted to make way for the new call must be informed that their call has been pre-empted, and have to make way for the higher precedence call.} \tn % Row Count 28 (+ 4) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\bf{Bandwidth admission policy}} Many calls could be active but bandwidth available may change. There must be a bandwidth policy in place that will manage the bandwidth available based on the levels of precedence marked in the message.} \tn % Row Count 33 (+ 5) \end{tabularx} \par\addvspace{1.3em} \vfill \columnbreak \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{MLPP Multi-level pre-emption and precedence (cont)}} \tn % Row 9 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\bf{Authorization of call placed}} Calls can be made using a higher level of priority by either inputting a specific priority code before a number or setting variable on the SIP UA via policies so that the caller always has a minimum priority level} \tn % Row Count 5 (+ 5) % Row 10 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{{\bf{Defined user interface}} If a call is pre-empted, the caller and callee are notified via a defined signal, visual message or tone, to that they know that their call has been pre-empted and there is no bandwidth available} \tn % Row Count 10 (+ 5) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SIP VVoIP QoS summary}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/seashore_1485816576_Screen Shot 01-30-17 at 06.48 PM.JPG}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Quiz}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Causes of jitter} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}over utilized LAN switch trunking ports; poor cabling;} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Packet carrying actual voice are transported using UDP} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}UDP} \tn % Row Count 6 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{RTP stands for} \tn % Row Count 7 (+ 1) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Which codecs have a MOS of 4.3} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}G.711 Alaw; G.722; G.711 U-law} \tn % Row Count 9 (+ 2) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{layer 2 classification is something routers will use to prioritize VoIP packets across a WAN link} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}false} \tn % Row Count 12 (+ 3) % Row 5 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Packetization rate is always fixed regardless of ITSP providing your service} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}false} \tn % Row Count 15 (+ 3) % Row 6 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{What is the default port for SIP messaging} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}5060} \tn % Row Count 17 (+ 2) % Row 7 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{what kind of info would rtcp generate on a network} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}sender report; application specific functions for a RTP session} \tn % Row Count 20 (+ 3) % Row 8 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{G.711 uLaw} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}64Kbps} \tn % Row Count 22 (+ 2) % Row 9 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{G.729a} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}8Kbps} \tn % Row Count 24 (+ 2) % Row 10 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{iLBC} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}13.33Kbps} \tn % Row Count 26 (+ 2) % Row 11 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{G.722.1} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}48Kbps} \tn % Row Count 28 (+ 2) % Row 12 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{How many bits can be used with a layer 3 DSCP} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}6 bits} \tn % Row Count 30 (+ 2) \end{tabularx} \par\addvspace{1.3em} \vfill \columnbreak \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Quiz (cont)}} \tn % Row 13 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Which port number the SIP device wants to receive RTP packets - audio 20016 RTP/AVP 0 8 18 96} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}20016} \tn % Row Count 3 (+ 3) % Row 14 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Which signaling protocol would allow a cisco ip phone to commuincate with a mitel pbx} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}SIP} \tn % Row Count 6 (+ 3) % Row 15 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Which is the 802 specification for vlans} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}802.1Q} \tn % Row Count 8 (+ 2) % Row 16 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{EF stands for enhanced forwarding when implemented on a route for re:QOS configuration} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}false - expedited forwarding} \tn % Row Count 11 (+ 3) % Row 17 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{G.711 uLaw} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}0} \tn % Row Count 13 (+ 2) % Row 18 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{G.729} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}18} \tn % Row Count 15 (+ 2) % Row 19 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{G.722} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}9} \tn % Row Count 17 (+ 2) % Row 20 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{iLBC} \tn \mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}dynamic} \tn % Row Count 19 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} % That's all folks \end{multicols*} \end{document}