Stull, Cory wrote: > > 3 locations. Milwaukee, Madison, Greenbay. Milwaukee and > Madison both > have a 128k port 64k CIR. Greenbay has full T1 with 64k CIR. > > From Milwaukee why is Greenbay's ping response times almost 3 > times faster > than Madisons? Wouldn't Milwaukee being the bottle neck of > 128k port rate > make both ping response times closer to the same?
The Milwaukee router would be a bottleneck if you were sending more traffic than the 128 Kbps interface can send. Once you start sending more than 128 Kbps, then the Milwaukee router has to start queuing packets, which would introduce some delay. For the delay to be noticeable, you would have to be doing quite a bit more than 128 Kbps. For it to be definitely noticable, you would need to exceed the queue depth, resulting in dropped and retransmitted packets. Does the router show that it is dropping any packets? What does the router say the load on the serial interface is? Where are the pings originating? What ping tool are you using? How much bandwidth can it use? Are delays being introduced between your ping station and the serial interface? For example, are they going across swithces or a shared Ethernet segment? My guess is that you aren't using 128 Kbps. Let's say that you are, though. Because Frame Relay is a packet-switched network, packets could be queuing up more in the path to Madison compared to the path to Greenbay. Also, of course, the egress FR relay switch in Greenbay can whip out the packets much faster than the egress switch in Madison which has just a 128 Kbps link, compared to the T1 link in Greenbay. So, it might seem odd that packets can pick up speed, but due to the queuing at routers and switches in the path, they can. They might get jumbled up at some point, but then whipped out at 1.544 Mbps at another point. I hope that explanation isn't too confusing and I hope you're not freezing there in Wisconsin! :-) Priscilla > Or is this > like the > highway theory of Greenbay has a Full T1 most of the way so you > can go > faster on that portion of the drive therefore the ping response > times are > much faster?? > > Thanks for any input. > > > > > Cory > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62552&t=62517 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
