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This report details preliminary models for a common-channel signaling system that sets up and tears down voice calls in a circuit-switched network. The initial Sections 1-3 present alternative detailed models for a single link between circuit-switched nodes. Section 4 outlines a heuristic procedure for calculating delays in a network; it makes use of an M/G/1 queueing approximation partially justified earlier. The simple illustrative problem addressed suggests approaches to a realistic network.

This report summarizes first year technical progress SFRC N00014-84-K-0734, 'Research in Distributed Tactical Decision Making: Decentralized Resource Management in Tactical Computer Executives,' for the period 1 August 1984 (contract start date) through 31 July 1985. This research reported herein in jointly funded by Office of Naval Research and Space and Naval Warfare Systems Command. The objective of this effort is to conduct research in the area of distributed tactical decision making Carnegie-Mellon University (CMU) proposed to conduct research on primarily two tasks in the first contract year. Task A considers best effort decision making for decentralized resource management. Task B focuses on the development of atomic transaction theories to support highly concurrent and reliable real-time computation. Innovative research under the guidance of the Principal Investigator was conducted on both of these tasks. Work will continue on both tasks in the second contract year. Keywords: Best effort decision making, Dynamic reconfiguration, Decentralized scheduling, Non-serializable transactions.

Markov population stochastic processes are useful in describing repairman and logistics problems, networks of queues, pharmacological processes, and manpower situations. This paper considers statistical estimation problems arising for such mathematical models. Parameter estimation of an empirical Bayes nature, with limited shrinkage or discrepancy tolerant features is discussed and illustrated. Additional keywords: Maximum likelihood estimation; Pharmacology; Statistical inference; Statistical analysis. (Author)

A probability model is presented for a set of communication channels that share the service of data and voice transmissions. A diffusion-theoretic approximation is derived, utilizing new results of Burman (1979). It is shown that the data queue (which is of low priority relative to voice) is approximated by a Wiener process. (Author)

A system of channels cooperatively services both voice and data messages arriving at one node of a communications network. This paper is devoted to the analysis of a particular channel-sharing strategy, in which voice traffic always occupies its channels when available, but data service is allowed to occur on empty voice channels. Voice traffic is taken to be of high priority; voice arrivals that find all voice channels busy are treated as losses. Note that voice traffic will be relatively infrequent as compared to data, and will also exhibit relatively long holding (service) times. Data traffic is taken to be heavy, and exhibits very short holding times (per word unit): compared to voice, data appears to arrive nearly continuously; when all data (and empty voice) channels are filled, queueing occurs., See also AD-A081 617.

A system of channels mutually accommodate both data and voice messages, voice having preemptive priority but being a loss system, and data being allowed to queue. Approximations to the data queue properties are derived. (Author), See also AD-A081 616.

A number of repairman-type models useful for describing and evaluating time-sharing computer systems with multitype users are presented and analyzed. Several approximation methods are introduced including one which allows for performance evaluation as a function of the queue discipline. Diffusion approximations are also considered, the accuracy of each of the approximation methods is assessed by numerical methods. The models proposed should prove to be useful for planning and evaluating both new and existing time-sharing computer systems. (Author)