Graphics Protocol: Level 0 only (RFC0292)
Original Publication Date: 1972-Jan-01
Included in the Prior Art Database: 2019-Feb-13
Internet Society Requests For Comment (RFCs)
J.C. Michener: AUTHOR [+4]
Network Working Group 12 January 1972 Request for Comment: 292 Jim Michener, MAC NIC 8302 Ira Cotton, MITRE References: 282, 285 Karl Kelley, U. of Ill. Updates: None Dave Liddle, Owens Ill. Obsoletes: None Ed Meyer, MAC
GRAPHICS PROTOCOL - LEVEL 0 ONLY
This document reflects opinions expressed and decisions reached at the second meeting of the Network Graphics Group, held at the Stanford Artificial Intelligence Laboratory in late November 1971. It describes part of a proposed Network Standard Graphics Protocol for transmitting graphics data within the ARPA network. The particular aspects of the protocol covered in this document relate to the form and content of graphics information sent from a source of graphical information (an application program, say, in the "Serving Host") to a display package for output to a graphics console (at the "Using Host"). This will take the form of a sequence of 8-bit bytes, and will be called the graphics output byte stream. In particular, only the simplest forms of graphics data will be covered in this, the first version of this document. The next version, already in preparation, will be much more complete. In any case this is not intended to describe a finished protocol; rather it should serve as a basis for graphics experimentation on the network.
This document does not include form or content of graphics input (data sent from the Using Host to the Serving Host) nor does it cover how the connection is established between the hosts. A proposal for the former will be generated eventually by this committee; the latter is the job of the Connection Committee (of the Network Graphics Group).
This RFC describes the commands which are available in the protocol in terms of the effect they would have at the receiving (Using Host) end. Clearly, some subroutine package is desirable at the Serving Host for use by applications package in transmitting graphics data, but on this topic this RFC does not intend to comment.
It may be observed by the reader that no facility is specified in this protocol allowing the Using Host to report logical errors in the graphics output byte stream to the Serving Host. Such a facility would have to be intergrated with the graphics _input_ byte stream, since it involves most of the problems related to synchrony of independent hosts.
Michener [Page 1]
RFC 292 Graphics Protocol Level 0 January 1972
The reader should probably peruse RFC 282: "Graphics Meeting Report" by Mike Padlipsky to obtain some of the framework surrounding this discussion of network graphics. Also it might be valuable to make note of the model described in RFC 285: "Network Graphics" by Donald Huff.
LEVEL AND GROUND RULES PERTAINING THERETO
Functions within the graphics protocol will be classified into a number of levels depending partly on how difficult it is to implement those functions. It is intended that any host which claims to implement the functions of level N must implement all lower level...