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This paper briefly reviews the distributed communication network concept in which each station is connected to all adjacent stations rather than to a few switching points, as in a centralized system. The payoff for a distributed configuration in terms of survivability in the cases of enemy attack directed against nodes, links or combinations of nodes and links is demonstrated. A comparison is made between diversity of assignment and perfect switching in distributed networks, and the feasibility of using low-cost unreliable communication links, even links so unreliable as to be unusable in present type networks, to form highly reliable networks is discussed. The requirements for a future all-digital data distributed network which provides common user service for a wide range of users having different requirements is considered. The use of a standard format message block permits building relatively simple switching mechanisms using an adaptive store-and-forward routing policy to handle all forms of digital data including digital voice. This network rapidly responds to changes in the network status. Recent history of measured network traffic is used to modify path selection. Simulation results are shown to indicate that highly efficient routing can be performed by local control without the necessity for any central, and therefore vulnerable, control point.

One in a series of eleven Memoranda detailing the Distributed Adaptive Message Block Network, a proposed digital data communications system based on a distributed network concept.

This Memorandum proposes a scheme by which each handgun and rifle in the country is modified so that its gun barrel leaves a predetermined tracing on all bullets fired. This tracing would be read as a unique binary-coded number corresponding to the serial number of the gun.

This Memorandum, the first in the series entitled On Distributed Communications, introduces the system concept and outlines the requirements for and design considerations of a digital data communications system based on the distributed concept, especially as regards implications for such systems in the 1970s. In particular, the Memorandum is directed toward examining the use of redundancy as one means of building communications systems to withstand heavy enemy attacks. While slightly survivable and reliable communications systems are of primary interest to those in the military concerned with automating command and control functions, the basic notions are also of interest to communications systems planners and designers having need to transmit digital data. (Author)

One in a series of eleven Memoranda detailing the Distributed Adaptive Message Block Network, a proposed digital data communications system based on a distributed network concept.

An elementary procedure for the synthesis of a character recognition device based upon a learning experiment is described. Utilizing information derived from a significant sample of the set of characters to be read and given identification of the samples by a human operator, a computer defines a set of 'filters.' These filters may then be used to transform unknown characters having similar type characteristics. During the recognition process a probability matrix for each character in the alphabet is used to compute a figure of merit for the hypothesis that an unknown character is the same as a known character. It is shown that this elementary model might adequately serve for construction of a fast input device for a language translation machine if it were able to make use of frequency distribution characteristics of the dictionary. A possible implementation with a raw character reading rate of up to 500 characters a second appears feasible. (Author)

This Memorandum, the eleventh and final volume in the series entitled 'On Distributed Communications,' summarizes the development of the system proposal. The more salient features of the system, presented in much greater detail in the other Memoranda in the series, are summarized, allowing the casual reader to obtain a general overview of the network. A reading of the introductory Memorandum in the series and the present Memorandum should suffice for a general understanding of the proposed Distributed Adaptive Message Block Network. (Author)

While the invasion-of-privacy problem has always been with us, its magnitude and complexion is changing. In the past, personal, sensitive information was kept in separate manual files. Specific individual permission was required any time an outsider wished information. As we look to the future and foresee greater integration of medical information systems, it may not be premature to think of the evolutionary development of such systems and the new problems they will create if adequate safeguards are not considered early and leaky systems prevented. (Author)

An examination of the usefulness of existing FM and TV stations as links in an emergency post-attack communications system.

This report details the Distributed Adaptive Message Block Network, a proposed digital data communications system based on a distributed network concept.