Scalable high-speed NDN name lookup

Abstract

Name lookup is a core function of the Named Data Networking (NDN) forwarding plane. It performs a name-based longest prefix match lookup against a large amount of variable-length, hierarchical name prefixes. NDN name lookup suffers a scalability challenge and needs to satisfy three key requirements: high-speed lookups, low memory cost, and fast updates. However, no existing work satisfies these requirements. Hash-based linear search schemes achieve fast updates and low memory cost but not high-speed lookups. Binary search (BS) schemes achieve high-speed lookups but slow updates with high memory cost. In this paper, we propose CBS, a hash-based counting binary search scheme for scalable high-speed NDN name lookup. CBS achieves fast updates and low memory cost, while sustaining high-speed lookups. The key to CBS is using a counter for each slot in a hash table to keep track of the number of markers that direct a search to find longer matching prefixes. This design not only allows fast updates by incrementing and decrementing counters, but also reduces the additional memory cost. Our experimental results demonstrate that CBS outperforms BS in update throughput, memory cost, and lookup throughput.