Thus spake "Jere Retzer" <[EMAIL PROTECTED]> > 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.<<<
Can you please upgrade to a MUA with standard quoting semantics? > 25 MS is assuming that the only delay is due to the speed of light. No. I'm asserting that every populated area in the U.S. is within 25ms ping time of a major exchange, absent congested pipes. > Add equipment, especially routers or other gear that requires manipulating > packets and the delays add up quickly. If your router(s), switch(es), or firewall(s) need more than 1ms to forward a packet, it's time to select a new vendor. It's 20 hops between my home and work box, including 2900mi of fiber, a couple firewalls, and a DSL link -- and that's only 80-90ms. We clearly don't need an exchange for every 100km2 to get acceptable RTT. What we need are uncongested pipes. > 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 ITU G.113 says users won't even notice the latency until it his 250ms. Do you have scientific studies that show 150-180ms is problematic? I'm sure the ITU (and a few hundred telcos) will be interested. Business experience shows users will tolerate over 1000ms latency if there's an economic incentive. There are many companies doing voice-over-internet that operate networks this way, and they're making a lot of money doing it. S