Showing papers on "Communications protocol published in 1979"

Modeling communications protocols by automata

Abstract: Using a pair of finite-state automata to model the transmitter-receiver protocol in a data communications system, we derive lower bounds on the size of automata needed to achieve reliable communication across an error-phone channel. We also show that, at the cost of increasing the size of the automata, a transmission rate close to the theoretical maximum can be achieved.

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.

Formal Methods for Communication Protocol Specification and Verification

Abstract: : Increasingly numerous and complex communication protocols are being employed in distributed systems and computer networks of all types This Note describes some of the more formal techniques that are being developed to facilitate design of correct protocols Our major conclusion is that it is vital to specify the services provided by a protocol layer in addition to specifying the cooperating protocol entities which make up the layer We develop service specifications of several representative protocols by using formal techniques from software engineering such as abstract machines and buffer histories A survey of protocol verification methods and a bibliography indexed by key phrases are also provided

Computer Network Protocols: A Hierarchical Viewpoint

Abstract: Progress in network protocol design brings us closer to fully-supported public data networks. These networks will provide message switching and computing services to a national user community.

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.