Patent · US Expired

Apparatus and methods for determining the correct workstation within a LAN for a LAN modem to route a packet

US6829239B1 · kind B1 · utility

55Cited by
10References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 9, 2003
Grant dateDec 7, 2004
Priority date
Expiry dateMay 9, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L61/00
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A LAN modem permits unambiguous routing for multiple workstations located on a LAN to each gain access through the LAN modem to any one of a number of different remote servers located on a number of different remote networks using a combination of public port number and public address of the workstation. There are instances where sessions are changed between the same workstation/server. This changing of sessions changes the public port numbers associated with each session, which destroys the above unambiguous routing, since the combination of a public destination IP address and a private destination port number is no longer the same unique value contained in an address translation table of the LAN modem. A four step hierarchical procedure is provided in which the LAN modem determines which workstation the packet is to be routed based upon value of fields stored in the network address translation (NAT) table or value of fields stored in a static table. The NAT table or static table entries are compared to the values of fields stored in the packet header.

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