Patent · US Expired

Method and apparatus for transparently bridging traffic across wide area networks

US5870386A · kind A · utility

43Cited by
13References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 30, 1991
Grant dateFeb 9, 1999
Priority date
Expiry dateDec 30, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L45/48
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A technique for logically connecting local area networks (LANs) that may be separated by wide area networks containing routers and other network components. A logical link is formed between two bridge-like devices called tunnelers, such that, once a tunnel has been established between two LANs, other devices on the LANs can communicate as if the tunnel were a bridge. The tunneling mechanism of the invention requires that each LAN or extended LAN have only one active tunneler at any particular time, referred to as the designated tunneler, and each of the tunnelers is configured to have knowledge of the identities of the other tunnelers. A tunnel is established after a successful exchange of messages between two tunnelers, and then traffic may be forwarded through the tunnel in a transparent manner. The tunneling mechanism permits messages to be forwarded between LANs separated by a wide area network containing routers. Moreover, the mechanism permits filtering of traffic, such that only selected types of traffic, or messages for selected destinations or from selected sources, are forwarded through tunnels. The tunneling mechanism inherently precludes the formation of closed communic…

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