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RFC 31 - Binary Message Forms in Computer Networks

  • Status: Unknown
  • Published: February 1968
  • Stream: Legacy
  • Errata: RFC 31 Errata

Document Information​

  • RFC Number: 31
  • Title: Binary Message Forms in Computer Networks
  • Authors: Daniel Bobrow (Bolt, Beranek, and Newman), William R. Sutherland (MIT Lincoln Laboratory)
  • Date: February 1968
  • Category: Unknown

Abstract​

RFC 31 proposes a notation for describing the content and intent of binary messages exchanged between computers. It argues that the established practice of drawing the binary bit stream as long thin rectangles and tabulating the bit options for each box obscures the structure of a message, and that a symbolic description method - analogous to the role ALGOL plays for algorithms and BNF for language syntax - would make message formats easier to understand and easier to publish as standards for new users of a network. The memo specifies a format description consisting of a title and four declarative sections: symbolic names for the simple fields, symbolic names for commonly used field values, characterization statements showing the legal ways of concatenating fields, and a declaration of the number of bits in each field together with any special bit-coding considerations. It defines the notation for field values with base indicators, for field equivalents, for characterization statements built from concatenation and alternatives, for repetition indicators, for assigning a field to a variable used as a repetition count, and for conditional fields and conditional alternatives enclosed in brackets. A complete illustrative example of a graphic data format is worked through.

Table of Contents​