Re: delay calculation


Nicolas Schmerber wrote:

Hello,

I'm new in networking and iperf usage. And I need a little bit help.
For a script project I must get this values from site A to site B :
Jitter delay, %loss pkts, and delay (not simple RTT)
I get easyly the 2 first parameters, but one thing : iperf gives jitter delay but not the delay (time to go from A to B)
Is there a way to calculate this ? A simple "ping" is not enough as the A <--> B line is asymetric so with a ping the time to A --> B isnt the same as B--> A .
Thanks for any help and sorry asking newbie questions.



You could time synchronize the 2 systems then send a timestamped message but I am not sure if you would get the resolution required using somthing like ntp.
Alternatly you could use very small ping packets and in that way minimize the component of your RTT that is purely related to the baud rate of the lines.
It should be possible to use various sized pings to bckward extrapolate the delay and somebody has likely done it somewhere and written it up.


--
Alvin Starr                   ||   voice: (416)585-9971
Interlink Connectivity        ||   fax:   (416)585-9974
alvin --at-- iplink.net              ||



Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index