The Application of ILP/ALF to Configurable Protocols

Antony Richards*, Ranil De Silva*, Anne Fladenmuller**,

Aruna Seneviratne* and Michael Fry*

* University of Technology, Sydney | Australia

** Universit?e Pierre et Marie Curie | France

December 16, 1994

Abstract

This paper demonstrates the feasibility of a configurable general purpose protocol. ALF and ILP will be used to overcome the performance penalty of the protocol functions with per byte operations. Results are given that show with ALF and ILP a good level of performance can be achieved within this framework.

1 Introduction

The development of distributed computing applications are being influenced by two major factors: the increasing capabilities of the high performance end systems and communication networks, and the diversity and dynamism of new applications. In terms of the OSI Reference model, the above two factors have moved the performance bottle-neck" to the higher layers of the communication systems (above layer 3).

Many studies have analysed the factors that govern the performance of these higher layers, especially the transport layer, and have proposed numerous solutions [4, 5, 6, 7, 13, 21, 24]. These solution have either investigated methods of improving hardware/software implementations or developed new protocol mechanisms that are optimised for a given application.

Improved software implementation methodologies proposed for the current protocols, such as Integrated Layer Processing and Application Layer Framing [6]; and Protocol Layer Bypass [23] show substantial improvements in performance. Newer protocol mechanisms for flow and error control and connection management have also provided appreciable performance gains. However, the improvement in performance alone is not sufficient to satisfy the needs of the new generation of applications, which have widely varying requirements. To satisfy these requirements it is necessary to tailor the communication system functionality to the application's needs.

Although application specific protocols have been advocated, [3, 9, 20], to our knowledge, a systematic study of the overheads associated with designing and implementing these protocols has not been studied. This article reports results of a study carried out to determine the possibility of implementing flexible, application specific protocols, and the effect of and integrated Layer Processing (ILP) on this model.

To appear in the First International Workshop on High Performance Protocol Architectures. HIPPARCH'94. INRIA, SOPIA ANTIPOLIS, FRANCE. 15-16 December 1994.