[c-nsp] IOS NAT throughput on LFN

[Steve Francis]

Anyone know how to increase TCP throughput when transitting a long fat 
network?
On cross country OC3 circuits, Machine to machine connections get about 
15Mbps using scp (I know ssh has its own windowing protocol - 15Mbps is 
fine.)
However, going through either a PIX or a router set up for NAT, the 
transfer drops to about 1Mbps.

Setting the ip tcp window-size 512000 seems to have no effect - its 
unclear from the docs if that applies to connections that are being 
NATd, or just traffic the router terminates for itself.

CPU load is no issue : < 1% on the router.
This is a 2800 running 12.3(11)T3.

Any ideas?
thanks