Patent · US Expired

Arrangement determining policies for layer 3 frame fragments in a network switch

US6798788B1 · kind B1 · utility

57Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 14, 2000
Grant dateSep 28, 2004
Priority date
Expiry dateJan 14, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L49/503
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A network switch, configured for performing layer 2 and layer 3 switching in an Ethernet (IEEE 802.3) network without blocking of incoming data packets, includes network switch ports, each including a policy filter configured for obtaining layer 3 and layer 4 information from a received layer 2 frame. The layer 3 information and the layer 4 information is used to determine a policy identifier that specifies a layer 3 switching operation to be performed on the received layer 2 frame. Each network switch port also includes a flow identification module that caches portions of the layer 3 information and the corresponding policy identifier. The cached portions of the layer 3 information and the corresponding policy identifier are then used by the flow identification module to identify the appropriate policy for subsequent fragmented layer 3 frames that lack the layer 4 information necessary for performing another policy lookup, but that have sufficient layer 3 information to uniquely identify each layer three flow. Hence, each layer 3 fragment can be assigned a unique policy for execution of layer 3 switching decisions.

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