Showing papers on "Protocol (object-oriented programming) published in 1979"

High level programming for distributed computing

Abstract: Programming for distributed and other loosely coupled systems is a problem of growing interest This paper describes an approach to distributed computing at the level of general purpose programming languages Based on primitive notions of module, message, and transaction key, the methodology is shown to be independent of particular languages and machines It appears to be useful for programming a wide range of tasks This is part of an ambitious program of development in advanced programming languages, and relations with other aspects of the project are also discussed

Development and Structure of an X.25 Implementation

Abstract: This paper describes experience with an implementation of the X25 communication protocols for accessing public data networks. Ihe implementation effort is characterized by: 1) the development of a formalized protocol specification on which all further implementation work is based, and 2) the use of Concurrent Pascal as the implementation language. The main features of the formalized protocol specification are given, and a method for deriving a protocol implementation based on parallel processes, monitors, and classes is explained. The overall structure of the system and the step-wise refinements leading to the complete implementation are discussed. Some comments on the possible implementation on multiple microprocessors are also given.

A cable-bus protocol architecture

Abstract: The benefits of general-purpose local networks are discussed and the requirements that such networks need to satisfy are defined. A generic network architectural model is described and the major design parameters identified. The role of the local network is to provide network transparency for a multiplicity of computer devices. How well this role is performed is a function of the protocol design and implementation.MITRE's Cablenet is one of several experimental cable-bus networks employing coaxial cable as a shared wideband transmission medium, and using microprocessor based interface units. This paper presents a protocol architecture design based on local network characteristics and the extensive computational capabilities expected from the next generation of microprocessors. We have designed a Flexible Transport Protocol which allows our cable-bus access node to assume a wide range of characteristics; these characteristics can be chosen judiciously to fulfil the needs of a wide spectrum of subscribers.

Programming Issues in Distributed Systems

Abstract: : The programmer in a distributed processing environment must be provided with a set of facilities which permit easy specification of the distributive properties of his/her program. The word program here is used to refer to either the output of a single compilation or the output of independent compilations of program modules which are to be communicating via an IPC. These distributive properties include the specification of the concurrency, data flow, resource requirements (memory, devices, etc.), and intraprogram (intermodule) protocol properties inherent in the execution of a configuration (system) of cooperating software modules. Given a description of these properties, an operating system must be able to distribute the user's program across multiple machines in a manner which is transparent to the programmer. Traditional approaches to providing these facilities include the concurrency support in high-level languages and the resource allocation and concurrency support in conventional operating systems.

WWMCCS Host to Front End Protocols Specifications Version 1.0

Abstract: : This document presents the specifications of the WWMCCS host to front end protocols. A brief overview of the WWMCCS network front end protocol architecture is presented. The link protocol is functionally specified. The channel protocol is completely specified. The complete channel protocol specification includes a narrative overview of the channel protocol mechanisms, a detailed treatment of each channel protocol message and event type, and a complete state table. A meta-specification for the service access protocols is presented.

Communications Protocol for a Building Automation System

Abstract: With the advent of microprocessors, it has become economical to distribute some of the building automation system (BAS) functions, once reserved for centralized minicomputers. With this comes a need for an efficient and economical communications protocol. Of chief concern in a BAS system are system response times and information throughput. Standard protocols (e.g. SDLC, HDLC, ADCCP, X.25, CAMAC) are general purpose protocols with high overheads. The high overheads associated with these protocols makes their use inefficient in a BAS. This paper describes the design considerations and tradeoffs in the design of JCI's proprietary BAS protocol. This protocol is a byte oriented, variable length polling protocol intended for use in several levels of distributed BAS networks.