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Design Alternatives for Computer Network Security



Gerald D. Cole, Dennis K. Branstad


The security problems associated with a network of computers are an extension of those of stand-alone computer systems, but require additional security controls due to the distributed and autonomous nature of the network components. The purpose of this investigation was to generate a pre-development specification for such security mechanisms by determining the issues and tradeoffs related to network security over a broad range of network applications, topologies and communications technologies. The approach which was taken was that of utilizing a dedicated network Security Controller (minicomputer) for checking the authentication of requestors, and, to some extent, for authorization checking as well. The enforcement of the Security Controller functions would be by means of Intelligent cryptographic Devices, which could be remotely keyed by the Security Controller when a requested communication was authorized. The Intelligent Cryptographic Device would incorporate the National Bureau of Standards Data Encryption Standard algorithm. The investigation showed that this approach is a viable solution to the network security problems of a large class of computer networks , and that such security mechanisms should be developed for operational usage.
Special Publication (NIST SP) - 500-21 Volume 1
Report Number
500-21 Volume 1


access control, authentication, communication, computer networks, cryptography, encryption, security


Cole, G. and Branstad, D. (1978), Design Alternatives for Computer Network Security, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 14, 2024)
Created December 31, 1977, Updated October 12, 2021