Showing papers on "Heterogeneous network published in 1986"

A formal protocol conversion method

Abstract: The need for the protocol conversion has been recognized with the proliferation of heterogeneous networks. From a formal viewpoint, we regard that problem as generating a protocol which satisfies the properties of the conversion. In this paper, we prove that, one can determine whether a converter exists, for some protocol classes, given protocols in the form of communicating finite automata, Moreover, we give a construction method for such a converter for those classes, and derive an upper bound of the computational complexity of the construction algorithm.

An Overview of the Army/DARPA Distributed Communications and Processing Experiment

Abstract: Emerging technologies in communications and information processing are having, and will continue to have, a significant effect on the way command and control (C2) is carried out on the battlefield of the future. One of these technologies is a packet-switched, internetwork, computer-communications system. This system concept allows for the interconnection of heterogeneous computers on heterogeneous networks, thereby providing for rapid, efficient, and reliable communications between processing elements-regardless of their physical location. This type of telecommunications architecture also allows automatic network reconfiguration when switching nodes or communications links fail. This permits system survivability in stressed environments. This communications system provides the means for passing time-critical information in a reliable and efficient fashion for purposes of C2. To achieve survivable C2, however, it is also necessary to integrate distributed software and data-processing technology with this telecommunications architecture technology. To achieve a survivable and effective C2capability, an experimental distributed command, control, and communications C3architecture has been evolved that blends these evolving communications and processing technologies with innovative concepts in tactical battle management. A joint Army/Defense Advanced Research Projects Agency (DARPA) Testbed, located at Fort Bragg, North Carolina, is being established to explore survivable C3concepts based on this architecture. This testbed, supported under the Army/DARPA Distributed Communications and Processing Experiment (ADDCOMPE), was started in late 1984. The ADDCOMPE testbed is leveraging the results of the earlier Army Data Distribution (ADDS) testbed also situated at Fort Bragg. However, ADDS primarily addressed communications; the ADDCOMPE program's emphasis is not only on communications but also on distributedprocessing environments (software and hardware) and distributed C2applications implemented over such an environment. In ADDCOMPE, the ADDS communications architecture is being taken as "available" technology but is being extended to include packet-switched, internetwork communications implemented over present-day Army communications systems. In this paper, an overview of the ADDCOMPE telecommunications architecture is presented and a discussion of the general philosophy for use of the ADDCOMPE testbed to support technology transfer to the Army is given. As this architecture is implemented, future papers will discuss its technical details, such as protocols used, throughput delay characteristics, and the like. Future papers will also provide technical discussions on the distributed-processing software (system and C2applications) developed for the testbed.

Synchronous communication protocols for local networks

Abstract: We propose protocols for the synchronous transmission of voice packets in local area networks. Two network models are considered: an all-voice network and a mixed voice and data network. The performance of the protocols is evaluated via simulation for these two network models.

Linked local area networks

Abstract: NETWORK SYSTEMS AND SERVICES General Principles of Networking Local Area Networks Personal Computer Networks and Micronets Wide Area Networks Network Services NETWORK TECHNOLOGIES Network Structures Equipment Linked to Networks Transmission Technologies Network Architectures Standards and Protocols Network Control and Performance NETWORK APPLICATIONS Office Systems and Business Systems Distributed Information Systems Distributed Computing Systems Other Applications of Networks WIDER ASPECTS OF NETWORKS Network Costs and Economics Impact of Networks Network Problems and Issues Future Prospects of Networks RECENT DEVELOPMENTS Recent Developments in Network Systems and Services Recent Developments in Network Technologies Recent Developments in Network Architectures Standards and Protocols Recent Developments in Network Applications Case Studies of Networks Current Network Problems and Prospects Appendixes Epilogue--The Peace Network Supplementary Bibliography Glossary Directory of Network Services Directory of Network System Suppliers Name Index Subject Index.

Grade of service and optimization of distributed packet-switched networks

Abstract: Packet-switched network optimization leads to specific problems related notably to the quality of service requirements to be take into account. The aim of this paper is to present methods for taking these quality of service constraints into account in the optimization process, particularly for heterogeneous networks (i.e. networks using several types of switch and several line capacities). These methods are based on the notion of diameter of graphs, and have been implemented in the computer programs Credo and Credo H, developed by CNET and currently used to plan the French public packet-switched network Transpac.

Application of ISDN to Interconnect Heterogeneous Switched Networks

Abstract: This paper proposes the use of the Integrated Services Digital Network (ISDN) to provide a high level of interoperability between existing heterogeneous networks, such as the Defense Switched Network (DSN) and the Initial Voice Switched Network (IVSN). The ISDN approach is a viable solution to the interoperability problem because it will offer off-the-shelf standard packages and flexible interfaces; these will permit a variety of connectivity options between heterogeneous networks with minimum development, and the possibility of minimum cost and risk. Described here are several different alternatives that illustrate the feasibility of exploiting ISDN capabilities.

Development and direction of network services

Abstract: The development of network services as applied to high-performance workstation technology is reviewed. The first workstations were often linked in local area networks (LAN) that were built without taking into consideration any of the other existing networks in an organization. The second stage of network services involved a backbone network, in which disparate groups were connected by a LAN. This stage was followed by the development of a cooperative operating system, then a network operating system, and finally an open network system. Potential network services which may lead to a true distributed computing environment are also briefly considered.