Hello,
I have a little problem with round trip delay computing and I am not sure if I am doing something wrong or there
is a bug within ethereal. To calculate the round trip delay I capture the RTCP protocol packets. I read the
sendind time of the Sender Report and the time of capturing the Receiver Report. Then I calculate the
difference of them. To get the round trip delay I have to substract from that result the "Delay since last SR
timestamp" value. The problem is that Delay is superior than the previous difference, so I will get a negative
result for the round trip time. Below is an example of my calculation:
Sender Report sending time: 34.522171 s
Receiver Report reception time: 35.339164 s
Difference=0.816993 s
Delay since last SR timestamp: 54208 which corresponds to 54208/65536=0.8271484375s (the unit of that field
is 1/65536 s, ref: RFC 1889 ).
Round trip delay=0.816993-0.8271484375=-0.010155s
Any ideas where is the problem?
Simon
Pour gagner une Playstation 2, envoyez un SMS avec le code PS au 61321 (0,35 euro hors coût du SMS).
