http://www.rfc-editor.org/rfc/rfc1307.txt
RFC 1307: Dynamically Switched Link Control Protocol, J. Young, A. Nicholson1992-03-01T23:00:00-00:00This memo describes an experimental protocol developed by a project team at Cray Research, Inc., in implementing support for circuit-switched T3 services. The protocol is used for the control of network connections external to a host, but known to the host. This memo defines an Experimental Protocol for the Internet community.