Multiprotocol transport networking: a general internetworking solution

Abstract

A user of computer networks has many choices for communication protocols. Current application programming interfaces (APls), such as sockets and CPI-C, run over some of these protocols. The trend toward global interorganizational networks is handicapped because programs written to one interface will often run on only one t>pe of transport network, and two programs must run on the same full protocol stack lo communicate. Ad hoc solutions exist, hut they are expensive and limited.The Multiprotocol rrangport Networking (XIPTh) architecture proposed in this paper is a general solution to providing interconnectivity far applications. The XIPTU architecture provides a protocol-independent system interface that includes most functions provided by existing transport protocols. As a result, the M P TN architecture decouples higher-layer protocols, application programming interfaces, and applications from protocols at the transport layer and helow. Using the MPTN architecture, existing and new applications can function unmodified over any transport supported under the ZlPTN interface. In addition, M P T N transport-layer gateways provide an end-to-end communication facility across a number of networks running different protocols. Therefore, a collection of networks running different protocols can serve as a single logical network.The paper describes four major aspects of the MPTN solution: a transport-layer protocol boundary, providing generic semantics at the transport layer so that the applications can he transport-independent; protocol compensation, adjusting for discrepancies between services required by generic transport layers and those provided by individual transport protocols; address mapping, resolving the difference u-hen the application and the protocol used to trarisport data use different address types; and general transport-level galeways, connecting networks running difkrent protocols. I This author is currently with Computer