Patent · US Expired

Virtual private networks and methods for their operation

US6937574B1 · kind B1 · utility

74Cited by
12References
56Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 16, 1999
Grant dateAug 30, 2005
Priority date
Expiry dateMar 16, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L61/5069
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

In methods and apparatus for routing packets through a communications network, a respective distinct broadcast address is assigned to each of a plurality of distinct sets of virtual ports. No virtual port belongs to more than one of the distinct sets. A respective egress address is assigned to each packet entering the network via an ingress virtual port. The respective egress address corresponds to a respective destination address of the entering packet when a correspondence between the destination address and an egress address is known. When no correspondence between the destination address and an egress address is known, the respective egress address is a broadcast egress address corresponding to the set comprising the ingress virtual port. The packet is routed according to the respective egress address. The routing is restricted to virtual ports belonging to the distinct set of virtual ports that includes the ingress virtual port. The distinct sets of virtual ports and their associated broadcast addresses define isolated virtual private networks within the network. Each physical port of the network may map one-to-one onto a corresponding virtual port, or may map onto a correspon…

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