Redundancy and Load Balancing Using IPv6 Anycast Addresses
An IPv6 anycast address is like any unicast address that is assigned to more than one interface (typically belonging to different nodes) where a packet sent to an anycast address is routed using the preferred route from the routing table. Anycasting is commonly used to load-balance between geographically dispersed servers.
For DS-Lite, redundancy and load balancing can be accomplished by:
Using multiple Services Physical Interface Cards (PICs) on the same Address Family Transition Router (AFTR) and a single anycast address for the softwire address.
Configuring the same anycast address on multiple AFTRs.
The advantage of configuring anycast addresses for AFTRs is that Internet Service Providers (ISPs) get service continuity and load balancing. In addition, the Basic Bridging BroadBand Element (B4) or the softwire initiator only needs to know a single AFTR IPv6 address.
