On Sun, 22 Nov 2009, capricorn 80 wrote: > I am looking to calculate the end-to-end delay between two soft > phone/hard phone. I have asterisk server and configured ntp server on > the same machine and synchronized it with ntp pool. I have seen that > Wireshark can be used to check the jitter. But I am not sure how can i > calculate the end to end. May be this is not related to the mailing list > topic but please help me if anyone has some information.
A very long time ago, I made the mistake of letting a client listen (with a handset on each side of his head) to end-to-end delay. This all of a sudden became a quest for the Holy Grail to quantify and reduce the delay. I got a couple of RadioShack telephone recording interfaces, connected one to each endpoint. Then I connected the outputs to the left and right channels on a PC and recorded "tapping" on one of the handsets using Audacity. When I selected the interval between the "tap" and the "ping," Audacity would show the time in ms. All very "old-school" but it worked and the client never questioned the "pretty pictures" on the computer screen. Wireshark may be able to tell you how long it takes a packet to travel across your network, but what about the time from the network interface on the host until sound comes out the earpiece? How long does it take a SIP phone to take a packet off it's network interface, wiggle it through it's jitter buffer, transcode it, convert it to analog and deliver it to the earpiece? -- Thanks in advance, ------------------------------------------------------------------------- Steve Edwards [email protected] Voice: +1-760-468-3867 PST Newline Fax: +1-760-731-3000 _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
