'Local/Remote' Forwarding Decision in Switched Data Link Subnetworks

摘要

The IP architecture assumes that each Data Link subnetwork is labeledwith a single IP subnet number. A pair of hosts with the same subnetnumber communicate directly (with no routers); a pair of hosts withdifferent subnet numbers always communicate through one or morerouters. As indicated in RFC1620, these assumptions may be toorestrictive for large data networks, and specifically for networksbased on switched virtual circuit (SVC) based technologies (e.g. ATM,Frame Relay, X.25), as these assumptions impose constraints oncommunication among hosts and routers through a network. Therestrictions may preclude full utilization of the capabilitiesprovided by the underlying SVC-based Data Link subnetwork. Thisdocument describes extensions to the IP architecture that relaxesthese constraints, thus enabling the full utilization of the servicesprovided by SVC-based Data Link subnetworks.