nanog mailing list archives

Re: PAIX


From: Jared Mauch <jared () puck Nether net>
Date: Mon, 18 Nov 2002 13:30:34 -0500


On Mon, Nov 18, 2002 at 10:13:48AM -0800, Jere Retzer wrote:


Stephen Sprunk wrote:

Any point in the US is within 25ms RTT (or less) of a major exchange; eliminating this 25ms of latency will have 
no effect on VoIP unless you're already near the 250ms RTT limit for other reasons.<<<


25 MS is assuming that the only delay is due to the speed of light. Add equipment, especially routers or other gear 
that requires manipulating packets and the delays add up quickly. I once read that the most people wil tolerate on a 
regular basis is around 150-180 ms. I think that is much too high for regular use

        True.

        As far as VoIP goes, take 2 (digital/pcs/gsm/whatnot) cell phones
(preferably on different carriers, or even the same if you want to see it)
and call the other phone.  Check out the delay in there.  People who
think that VoIP needs low delay don't realize the [presumably compression
and other dsp related] delays introduced that people will be able to
withstand.

        - jared

-- 
Jared Mauch  | pgp key available via finger from jared () puck nether net
clue++;      | http://puck.nether.net/~jared/  My statements are only mine.


Current thread: