Brian Dickson wrote:

such peer networks). Ingress traffic to the web farm provider has it's *source* address NAT'd, and internal routing points return traffic to the *same* NAT through which the request traffic came. Thus, return (data) traffic is best-exit.

Side benefits are that the unique address pools allow for much easier per-peer and per-region collection of stats, eg netflow (at some place other than NATs).

As you point out, stats collection is easier--but only from a network ops point of view, and even then, only if you're simply concerned with symmetric flow of traffic to your upstreams/peers. However, your web server logs are now useless, because all the requests come from a static pool of local addresses. If you're a big web farm like Exodus, your customers aren't going to buy this. -Jeff -- Jeff Mayzurk Manager, Systems/Network Engineering <jeffm@eonline.com> E! Online 150 Chestnut Street 415.772.3555 x4496 San Francisco, CA 94111 415.984.0322 FAX