Patent · US Active

Efficient longest prefix matching techniques for network devices

US9819637B2 · kind B2 · utility

9Cited by
41References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 27, 2014
Grant dateNov 14, 2017
Priority date
Expiry dateJul 6, 2035

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L45/7453
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A network address associated with a packet is obtained at a search engine of a network device. The search engine includes a plurality of Bloom filters that represent prefixes of respective lengths in the routing table. Respective Bloom filters are applied to respective prefixes of the network address to determine a set of one or more prefixes for which a match potentially exists in the routing table. A number of accesses to the memory are performed using prefixes in set of prefixes, beginning with a longest prefix and continuing in decreasing order of prefix lengths until a matching entry is found in the routing table, and routing information for the packet is retrieved. If the number of performed memory accesses exceeds a threshold, the routing table is adapted to reduce a number of memory accesses to be performed for subsequent packets associated with the network address.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.