BGP: Difference between revisions
→Community
Line 197:
= Community =
Source: [http://www.networkers-online.com/blog/2008/09/understanding-bgp-communities/ networkers-online.com]
*A numerical value that can be assigned to a specific prefix and advertised to other neighbors.
*When the neighbor receives the prefix it will examine the community value and take proper action whether it is filtering or modifying other attributes.
*By default the community attribute is removed from the update before being sent to the neighbor.
*To allow community values to be sent to a specific neighbor
neighbor x.x.x.x send-community
*BGP has default 4 well known communities that can be used to mark prefixes; listed as follows:
Internet: advertise these routes to all neighbors.
Local-as: prevent sending routes outside the local As within the confederation.
No-Advertise: do not advertise this route to any peer, internal or external.
No-Export: do not advertise this route to external BGP peers.
= Synchronization =
| |||