Range Tries for scalable address lookup

In this paper we introduce the Range Trie, a new multiway tree data structure for address lookup. Each Range Trie node maps to an address range [Na, Nb) and performs multiple comparisons to determine the subrange an incoming address belongs to. Range Trie improves on the existing Range Trees allowing shorter comparisons than the address width. The maximum comparison length in a Range Trie node is log2(Nb - Na) bits. Address parts can be shared among multiple concurrent comparisons or even omitted. Addresses can be properly aligned to further reduce the required address bits per comparison. In so doing, Range Tries can store in a single tree node more address bounds to be compared. Given a memory bandwidth, more comparisons are performed in a single step reducing lookup latency, memory accesses per lookup, and overall memory requirements. Latency and memory size scale better than related works as the address width and the number of stored prefixes increase. Considering memory bandwidth...

• Type: Journal
• Year: 2009
• Where: ANCS
• Authors: Ioannis Sourdis, Georgios Stefanakis, Ruben de Smet, Georgi Gaydadjiev
• Keywords: Address Width, ANCS 2009, Computer Networks, Range Trie, Range Trie Node