Hi all list, My presentation: I am david grau and I am from barcelona. Excuses for my poor english.
I don't know exactly if this mail-list is the appropiate site to say what I am doing... so, if not, please, tell me where can I go to say that... My project objective is monitor and evaluate a wireless VoIP (SIP) peer to peer session by analysing RTCP control stream and filtering performance parameters such as jitter, delay and packet loss. These values will be dynamically plotted in order to provide a visual synopsis of network health. I use a command line network sniffer to capture the relevant control packets i.e. RTCP sender and receiver reports. I parse the RTCP sender and receiver reports to filter out values for jitter, delay and packet loss. I show you part of the parsing: TIMESTAMP 18:31:01.248701000 SENDER REPORT MSW: 3351349861 LSW: 1073741824 Sender's packet count: 2 Sender's octet count: 320 RECEIVER REPORT Cumulative number of packets lost: 0 Extended highest sequence number received: 0 Interarrival jitter: 0 Last SR timestamp: 2321891328 Delay since last SR timestamp: 1 TIMESTAMP 18:31:01.280097000 SENDER REPORT MSW: 3351349861 LSW: 1206885810 Sender's packet count: 4 Sender's octet count: 640 RECEIVER REPORT Cumulative number of packets lost: 0 Extended highest sequence number received: 0 Interarrival jitter: 0 Last SR timestamp: 2321893359 Delay since last SR timestamp: 1 TIMESTAMP 18:31:06.280193000 SENDER REPORT MSW: 3351349866 LSW: 1541893259 Sender's packet count: 190 Sender's octet count: 30400 RECEIVER REPORT Cumulative number of packets lost: 0 Extended highest sequence number received: 58034 Interarrival jitter: 165 Last SR timestamp: 2322226151 Delay since last SR timestamp: 1 I am a newbie and I don't know what exactly I have to do with these values. I need to calculate delay, jitter and packet lost but I am confuse... Just I know how can I calculate jitter: Jitter is measured by RTCP software and included in the RR messages sent by the receiver. As this value is measured in sampling units, in order to convert to time units, one must divide by the sampling rate of the media codec. Again using the example data, we have jitter values of 227 and 335 sampling units, which, when divided by ITU-T G.711 sampling rate of 8 kHz, correspond to 28.375 ms and 44.125 ms, respectively. Is anybody available to explain an example to calculate delay and packet lost? Thanks in advance. david grau _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
