Here it is:
1-If NextHop is inaccessible do not consider it.
2-Prefer the largest Weight.
3-If same weight prefer largest Local Preference.
4-If same Local Preference prefer the route that the specified router has
originated.
5-If no route was originated prefer the shorter AS path.
6-If all paths are external prefer the lowest origin code
(IGP<EGP<INCOMPLETE).
7-If origin codes are the same prefer the path with the lowest MED.
8-If path is the same length prefer the External path over Internal.
9-If IGP synchronization is disabled and only internal path remain prefer
the path through the closest IGP neighbor.
10-Prefer the route with the lowest ip address value for BGP router ID.
Mike
-----Original Message-----
From: Jay Stewart [mailto:cosmo@olywa.net]
Sent: Monday, November 22, 1999 12:16 PM
To: cisco-nsp@puck.nether.net
Subject: [nsp] BGP4 Route Selection Criteria
Can someone send me the route selection criteria that BGP4 uses to
determine which route is most preferrable?
>From my understanding, all things being equal, a shorter AS-Path will
be chosen, regardless of the length of the prefix. In other words, if
I advertise 10.0.0.0/8 with as path - {AS1 AS2}, and I advertise
10.0.10.0/24 with as path prepending as such - {AS1 AS2 AS2}, will
remote routers select the longer AS Path route due to the shorter
prefix?
Jay Stewart
Vice President
Olympia Networking Services - "The Northwest's Premier ISP"
http://www.olywa.net
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