This preview shows page 1. Sign up to view the full content.
Unformatted text preview: When a unicast address is assigned to more than one interface, thus
turning it into an anycast address, the nodes to which the address is assigned must be explicitly configured to know that it is an
anycast address. For any assigned anycast address, there is a longest prefix P
of that address that identifies the topological region in which all interfaces belonging to that anycast address reside.
the Within region identified by P, the anycast address must be
maintained as a separate entry in the routing system (commonly referred to as
a "host route"); outside the region identified by P, the anycast
address may be aggregated into the routing entry for prefix P. Note that in the worst case, the prefix P of an anycast set
may be the null prefix, i.e., the members of the set may have no
topological locality. In that case, the anycast address must be
maintained as a separate routing entry throughout the entire Internet, which
presents a severe scaling limit on how many such "global" anycast sets
View Full Document
- Fall '13