Not saying this is what others do, but you can certainly use that criteria (via a route-map) to control whether a route is prefered by a peer over two identical (in all other aspects) paths. DJ Peter Boothe wrote:

What makes you mark routes as ORIGIN: IGP vs ORIGIN: EGP?

I just checked out the latest routeviews snapshot to see what the origins of various routes were set to. The command line $ bzcat oix-full-snapshot-latest.dat.bz2 | sed -e 's/.* //' | sort \ | uniq -c | sort -nk1 Gave me a bunch of crap from overly-long lines, and then 9091 e 682087 ? 7560175 i

Which means that out of 8,251,353 routes in routeviews, only 9,091 are marked as ORIGIN: EGP, while 682,087 are not configured as one or the other, and the other *7.5 million* are marked ORIGIN: IGP.

So my question is: What do people use ORIGIN: EGP vs ORIGIN: IGP to distinguish? What makes a route EGP vs. IGP to you?

-Peter

-- Peter Boothe Graduate Student in Computer Science Beyond BGP Project University of Oregon http://soy.dyndns.org/~peter

On Thu, Oct 20, 2005 at 10:34:35PM -0700, Peter Boothe wrote:

So my question is: What do people use ORIGIN: EGP vs ORIGIN: IGP to distinguish? What makes a route EGP vs. IGP to you?

Origin is a mandatory transitive attribute which is being used in the BGP decision algorithm. If you have a prefix with the same localpref and aspath-length, the decision will be made based on the lowest origin-value. IGP wins over EGP, EGP wins over incomplete. You might use it to influence your inbound traffic. -- Sabri please do not throw salami pizza away