[c-nsp] Network performance question - TCP Window issue?

[CiscoNSP_list CiscoNSP_list]

> 
> On 29/04/2012, at 5:34 PM, CiscoNSP_list CiscoNSP_list wrote:
> > Have 3 POPs A,B+C (A connected to B via 200Mb Eth, B connected to C via 250Mb Eth), all POPs are 7200's with 2960's and 3560's
> > 
> > Latency:
> > 
> > A -> B,  2 - 3 m/sec (No packet loss, minimal jitter)
> > B -> C, 12 - 13 m/sec (No packet loss, minimal jitter)
> 
> There is a huge latency difference between A-B and B-C. (about 5 times!)
> How far are these sites apart?


A+B about 70K's
B+C about 1000K's

I've just checked in the opposite direction (C -> A) and I see ~4.5M/s - A's on a 10/100 port, C's on a Gig port...so pulling from C->A would be Gig, 250, 200, 100 (where I see 2.15M/s), but in the other direction (pulling from A->C) would be 100, 200, 250, Gig...


> 
> This might also make some good reading:
> 
> http://knol.google.com/k/understanding-network-and-internet-latency
> 

Thanks - Will have a read.