05309437 is referenced by 277 patents and cites 15 patents.

A device and related method for coupling segments of an extended local area network (LAN) in such a way that message traffic employing inter-network protocols such as TCP/IP will be handled without the difficulties usually associated with bridges, and without the complexity and expense of full IP router capability. The device operates like a bridge for non-TCP/IP traffic. For TCP/IP traffic it operates in a bridge-like manner but maintains a database associating extended LAN segment addresses with port numbers in the device, so that packets can be automatically forwarded over a spanning tree connecting the network segments. A host computer in any network segment can address others in different network segments of the extended LAN as though all were in a single LAN. The device of the invention functions to block the flow of ARP messages and to generate ARP replies that render the device of the invention transparent to hosts within the extended LAN. The device is also transparent to true IP routers, which may still be used to effect communication with points outside the extended LAN.

Title
Bridge-like internet protocol router
Application Number
7/546619
Publication Number
5309437
Application Date
June 29, 1990
Publication Date
May 3, 1994
Inventor
G Paul Koning
Brookline
NH, US
Radia J Perlman
Acton
MA, US
Agent
Noel F Heal
Albert P Cefalo
A Sidney Johnston
Assignee
Digital Equipment Corporation
MA, US
IPC
H04J 3/02
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