RFC 199 SUGGESTIONS FOR A NETWORK DATA - TABLET 15 July 1971 DATA - TABLET GRAPHIC INPUTS

The purpose of this document is to add SDC’s comments to the discussion of a protocol for network graphics within the ARPA Network community. In general, we are concerned with the development of the graphics protocol in two areas: non-interactive graphics and datatablet graphics, as opposed to fully interactive graphics. By noninteractive graphics we mean situations in which there is little or no requirement for interaction with displays. Such displays are used, for instance, in data retrieval systems using graphics to display retrieved information in the form of charts, X-Y graphs, histograms, scatter plots, tabular displays, etc. In these systems, each interaction with the system produces an entirely new display. The displays themselves have little, if any, structure. There is no necessity to interact with the picture itself other than, perhaps, by the use of light buttons. It is important that non-interactive graphics be simple to implement and use on the network. Therefore, we suggest that the graphics protocol design be based upon noninteractive graphics systems and that capabilities needed for interactive graphics be added as a super-set. This will ensure that the protocol complexities associated with interactive graphics do not impose problems for the user of non-interactive graphics, as they would if a non-interactive subset were developed from a protocol based initially on interactive graphics. The section of Request for Comment (RFC) 177 describing actual display instructions contains a good basis for the development of a non-interactive graphics protocol. With it as a starting point, a protocol for the generation of a picture can be developed, and the organizational and structural information useful for interactive graphics can be developed later.