Of course it can work. My point is that it is a fact of life, nothing more. Pointing out the obvious: Dependent upon who is/are your upstream provider(s), and how specific the prefix announcements are made to their peers (re: your reachability) determines just how symmetric your traffic patterns will be. - ferg -- "Michel Py" <michel@arneill-py.sacramento.ca.us> wrote:

Asymmetric paths are a fact of life in the Internet.

Not for enterprise operators except the largest ones. Asymmetric traffic does happen in the core, where there are no firewalls or NATs; as far as the edge is concerned though I know several companies that multihome to two or more ISPs but only in one location, largely because they don't want to deal with NAT/firewall issues. Although it can work, it requires extra engineering and most of the time a fat pipe to replicate state information between the sites. -- "Fergie", a.k.a. Paul Ferguson Engineering Architecture for the Internet fergdawg@netzero.net or fergdawg@sbcglobal.net