Re: IGP metrics on WAN links

[Warren Van Camp <vancamp () sonic net>]

At 01:24 PM 7/19/02 -0700, Joe Abley wrote:

> Yeah, my (limited) experience is the opposite. At the previous large
> operator at which I had enable, the IGP metrics were chosen primarily
> according to circuit size, and were subsequently tweaked for other
> issues (such as circuit latency, or the requirement to balance cross-
> US traffic across non-parallel circuits).

I would expect that approach wouldn't scale as well as the network
grows in complexity, since it will be much more sensitive to unexpected
traffic flow changes due to addition of new circuits or routers.

Definitely, congestion is an issue.  If you've got backbone congestion, 
you better be tweaking your traffic as best you can in any case.  But the 
network should behave in an intuitive manner with minimum latency 
(shortest distance) as much as possible.

Warren Van Camp.