RFC 1307 (rfc1307) - Page 2 of 13
Dynamically Switched Link Control Protocol
Alternative Format: Original Text Document
RFC 1307 Dynamically Switched Link Control Protocol March 1992 1.1 Motivation Circuit Switched Networks are becoming available to the Internet community. These networks are made available by requesting a connection through a switch. Normally circuit switched network links are disconnected, and their prohibitive cost suggests that it is very costly to leave them connected at all times. Internet users and hosts wish to send data over a circuit switched networks, but only connect the network links when a transport connection is to be established. While it would be possible to use packet routers to identify the need for switching a connection on and off, only the transport provider can positively identify the beginning and end of a transport session. There must be a mechanism to activate and deactivate the link at the beginning and end of a transport session. The DSLCP assumes that a transport provider has knowledge of a downstream link which must be setup before data transfer may take place. However, the details of link setup may vary by the type of link (circuit-switched or other), specific hardware, or administrative differences. The DSLCP hides these details from the transport provider by offering a simple request/release model of link preparation. The model assumes an entity in control of the link which handles the details of connection preparation while responding to the DSLCP commands of the transport provider. This entity is called the link controller. The DSLCP allows internet hosts to dynamically change the fabric of the internet by sending messages through the internet in advance of data which is to travel across the newly created links. 1.2 Scope DSLCP is intended to provide an interface between transport providers and arbitrary network links requiring creation, control, setup, or conditioning before data communications may take place. 1.3 Interfaces There are no specific user level interfaces to DSLCP, although they are not precluded. Link control is a function of the network layer, initiated by requests from the transport provider. A DSLCP transaction is defined as a transport provider communicating with a link controller for the duration of transport session. A network path between the host providing transport services and the link controller must exist in advance of the DSLCP transaction. Young & Nicholson
