[nsp] I need ideas on how to simulate a 200ms round-trip latency and bandwidth limitation.

[atticus at satanic.org]

>  Specifically, I'm interested in the impact (if any) of implementing the
> "ip tcp window-size" command on a 1721 router.

As mentioned already, this is only going to change the window size for
router-initiated connections.

> We have several VSAT links overseas, and I'm thinking of pushing the ISP
> on the US side to implement this feature on their routers

One thing to look at is RBSCP that showed up in 12.3T:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123newft/123t/123t_7/gt_rbscp.htm

Haven't had a chance to play with it yet, but have it in the back of my
head to try for some very long VPN tunnels. The major caveat I saw is all
traffic is process-switched, so it almost certainly will chew up your 1721
in no time.

> The Cisco docs suggest setting the value to 750000, but don't go into
> much detail about how they arrive at that figure.

Your best reference to this will probably be:

  http://www.psc.edu/networking/perf_tune.html