Viewserver hierarchy: a new inter-domain routing protocol

The authors present a new viewserver hierarchy and associated protocols that (1) satisfies policy and type-of-service (ToS) constraints, (2) adapts to dynamic topology changes including failures that partition domains, and (3) scales well to a large number of domains without losing detail. Domain-level views are maintained by special nodes called viewservers. Each viewserver maintains a domain-level view of a surrounding precinct. Viewservers are organized hierarchically. To obtain domain-level source routes, the views of one or more viewservers are merged (up to a maximum of twice the levels in the hierarchy). Their evaluation results indicate that the viewserver hierarchy finds many short valid paths and reduces the amount of memory requirement by two orders of magnitude.