Best Practices for Enterprise networks

Mon Aug 30 00:50:39 UTC 2004

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 at 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 at netzero.net or
 fergdawg at sbcglobal.net