Mike: Our web site at http://sla.cw.net/ provides you with real time RTT measurements on our network. That should give you a good picture of typical large network response times. Regards Peter Jansen Global Peering Cable & Wireless Date: Mon, 25 Mar 2002 10:13 -0500 (EST) From: "Pistone, Mike" <Mike.Pistone@msfc.nasa.gov> To: "'nanog@merit.edu'" <nanog@merit.edu> Sender: owner-nanog@merit.edu Delivered-to: nanog-outgoing@trapdoor.merit.edu Delivered-to: nanog@trapdoor.merit.edu Delivered-to: nanog@merit.edu Subject: Transatlantic response times. I wasn't really sure where to post this, but I figured NANOG would have some insight or at least experience here. I was curious if anybody would share what they consider to be average or acceptable transatlantic ping response times over a T1. I know there are tons of variables here, but I am looking for ballpark figures. Assume that utilization on the circuit is extremely low, and you are measuring point to point across the line. You can also assume no other bottlenecks effecting the response times (router performance, or what not). Should you see a ~150ms trip? 250ms? 450ms??? Also, if possible, include the to and from info. Obviously NYC to London is a bit different than Dallas to Prague or something. Is there any equation to estimate response times? For example, if your circuit from A to Z has a 500ms avg response, than that equates to a circuit distance of aprox. 5000 miles or something? Thanks in advance, Mike