> On Fri, Apr 3, 2009 at 10:12 AM, Sebastian Mellmann > <sebastian.mellmann at net.t-labs.tu-berlin.de > <mailto:sebastian.mellmann at net.t-labs.tu-berlin.de>> wrote: > > Hi everyone! > > After each call 'pjusa' prints some information about the past call. > > An example summary looks like this: > > [DISCONNCTD] To: sip:30.30.30.1;tag=04YY1YX4-0S0HH2yi7LWNBSZ8mXDD9jy > Call time: 00h:01m:01s, 1st res in 71 ms, conn in 71ms > SRTP status: Not active Crypto-suite: (null) > #0 PCMU @8KHz, sendrecv, peer=30.30.30.1:4000 > <http://30.30.30.1:4000> > RX pt=0, stat last update: 00h:00m:01.243s ago > total 2.7Kpkt 444.3KB (555.4KB +IP hdr) > @avg=58.1Kbps/72.7Kbps > pkt loss=276 (9.0%), discrd=1 (0.0%), dup=0 (0.0%), > reord=0 (0.0%) > (msec) min avg max last dev > loss period: 20.000 22.258 60.000 20.000 6.820 > jitter : 0.000 0.337 1.750 0.750 0.278 > TX pt=0, ptime=20ms, stat last update: 00h:00m:01.555s ago > total 3.0Kpkt 488.8KB (611.0KB +IP hdr) @avg > 64.0Kbps/80.0Kbps > pkt loss=308 (9.2%), dup=0 (0.0%), reorder=0 (0.0%) > (msec) min avg max last dev > loss period: 340.000 513.333 720.000 480.000 56.446 > jitter : 0.125 0.208 0.250 0.125 0.058 > RTT msec : 0.762 1.252 2.817 2.817 0.705 > > I'm not sure what the 'loss period' and 'jitter' values mean. > How can I interpret those values? > I know what 'jitter' means, but not in this case. > > > Loss period means the period on which we didn't have audio, due to > packet loss. There are some definitions/explanations in RFC 3357, not > sure if this helps or not. But the main use in our case is to have > some understanding about the nature of the packet losses, i.e. if we > have total of 10 packet losts, the loss period helps us to know > whether these losses are random/one by one (in this case the loss > period would be 1 frame/20ms) or in a burst (in this case the loss > period would be more than 1 frame). > So in the above example the loss period on the transmitter side means that we had no audio for 340ms minimum, 720ms maximum etcpp.? > I'm not sure which part of jitter that's not clear. > The definition of jitter I know is: The jitter represents the variance of the runtime of a data packet. The question is, what does those 'min' 'max' etc. jitter values in the summary tell me? For example I see a 'min' jitter value of 0.000 on the RX side. What does this mean? > cheers > Benny > Regards, Sebastian
