Some factors which a Network Graphics Protocol must consider (RFC0192)
Original Publication Date: 1971-Jul-12
Included in the Prior Art Database: 2002-Mar-05
Internet Society Requests For Comment (RFCs)
It is our contention that, if computer graphics is to be widely useful, the graphics terminals must be just another type of terminal on a timesharing system with minimal special privileges. In these brief notes we outline the basic features which we feel must be available in a graphics support package to allow easy interactive graphics application programming.
Network Working Group R. Watson
Request for Comments: 192 SRI-ARC
NIC: 7137 12 July 1971
Some Factors which a Network Graphics Protocol must Consider
After reading some of the RFC's on a network graphics protocol it
seems that many are not providing general enough mechanisms to handle
attention handling, picture structure, and other higher level
processes involved in interactive graphics.
Therefore for what it is worth I am sending out these rough
introductory notes which contain ideas that I think any network
graphics protocol must come to grips with.
The network graphics protocol should allow one to operate the most
sophisticated system with more general data structures and concepts
than those described in these notes and allow very simple systems to
It is our contention that, if computer graphics is to be widely
useful, the graphics terminals must be just another type of terminal
on a timesharing system with minimal special privileges. In these
brief notes we outline the basic features which we feel must be
available in a graphics support package to allow easy interactive
graphics application programming.
If one examines the types of tasks in industry, government and
universities which can avail themselves of timesharing support from
graphics consoles, one can estimate that the large majority can
effectively utilize quite simple terminals such as those employing
storage tubes. I would estimate 75% of the required terminals to
fall in this class. Another 15-20% of terminals may require higher
response and some simple realtime picture movement, thus requiring
simple refresh displays. The remainder of terminals are needed for
high payout tasks requiring all the picture processing power one can
make available. In this talk we are not considering support for this
latter class of applications.
MAIN ASSUMPTIONS AND REQUIREMENTS FOR SYSTEM DESIGN
The main assumptions and requirements underlying the interactive
graphics are the following:
Watson [Page 1]
RFC 192 Some Factors which a Network Graphics 12 July 1971
1) The user of the graphics terminal should be just another
timesharing system user.
2) The graphics software support should interface to existing
3) The software support should allow technicians, engineers,
scientist, and business analysts as well as professional
programmers to easily create applications using a graphic
4) The software support should easily allow use of new terminals
and types of terminals as they come on the market.
5) The software support should be expandable as experience
indicates new facilities are required.
6) The software support should be portable from one timesharing
service to another.
7) Some form of hardcopy should be available.
MULTILEVEL MODULAR APPROACH TO SYSTEM DESIGN
If one wants to create as system which is easy to use by
inexperienced programmers and ultimately non-programmers, one needs
to provide powerful problem-oriented aids to program writ...