BGP CHAPTER 4

BGP CHAPTER 4
QUESTIONS:
11. What is BGP Default Path Selection ?
12. What is route-map ?

Solution:
11.What is BGP Default Path Selection ?

Prefer the route with the highest weight (a local, Cisco-proprietary parameter).
Prefer the route with the highest local preference.
Prefer locally-originated routes over those learned from a neighbor.
Prefer the route with the shortest AS path.
Prefer IGP-learned routes over those with an unknown origin.
Prefer the route with the lowest MED (per AS).
Prefer EBGP-learned routes over IBGP-learned routes.
Prefer the route whose next-hop address has the lowest IGP metric.
Multipath determination
If a best path exists, prefer it over newer routes.
Prefer the route from the router with the lowest router ID.
If the router IDs match, prefer the lowest neighbor IP address.

12. What is route-map ?

An ordered list of statements processed similar to an access-list.
Perform a series of if > then statements (match /set)
Typically used for :
Modifying BGP attributes
Policy Routing
Route Filtering