Patent · US Active

Using ternary and binary content addressable memory stages to classify information such as packets

US7602787B2 · kind B2 · utility

47Cited by
68References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 28, 2005
Grant dateOct 13, 2009
Priority date
Expiry dateMay 12, 2027

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S707/99933
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Methods and apparatus are disclosed herein for classifying packets using ternary and binary content-addressable memory stages to classify packets. One such system uses a stage of one or more TCAMS followed by a second stage one or more CAMS (or alternatively some other binary associative memories such as hash tables or TRIEs) to classify a packet. One exemplary system includes TCAMs for handling input and output classification and a forwarding CAM to classify packets for Internet Protocol (IP) forwarding decisions on a flow label. This input and output classification may include, but is not limited to routing, access control lists (ACLs), quality of service (QoS), network address translation (NAT), encryption, etc. These IP forwarding decisions may include, but are not limited to IP source and destination addresses, protocol type, flags and layer 4 source and destination ports, a virtual local area network (VLAN) id and/or other fields.

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