SRAN: Scaling NDN Routing via Map-and-Attach
Network routing scalability becomes difficult when forwarding state scales with an external identifier space rather than network topology. Named Data Networking (NDN) faces this challenge acutely because routing directly on application name prefixes ties forwarding state to an unbounded namespace. This paper presents SRAN, an intra-domain NDN routing architecture that applies the routing-scalability principle underlying Map-and-Encap through Map-and-Attach: application prefixes are mapped to egress routers, and the resulting mapping information is attached to the original Interest. This enables network routing and forwarding to operate on topological identifiers while keeping NDN Interests intact and preserving native NDN communication semantics, including Interest/Data exchange, in-network caching, and data-centric security. SRAN further uses the same prefix-to-egress mapping to realize Bit Index Explicit Replication (BIER) for scalable NDN Interest multicast. SRAN leverages existing NDN mechanisms to securely maintain prefix-to-router mappings among user-facing routers without introducing new protocols. Evaluation on Rocketfuel topologies shows that routers' forwarding state scales with network topology rather than application-prefix count, while prefix updates are disseminated in real time with low communication overhead.