Network Working Group R. Watson
Request for Comments: 592
NIC 20391 November 1973
Some Thoughts on System Design to Facilitate Resource Sharing
There is a growing interest in moving toward more resource sharing on
the ARPANET. Some resource sharing has been taking place by having
systems open TELNET connections and generating user command strings.
I think that this is fine for experimental use, but is not the way we
want to operate in real usage. What I believe network system
builders should do is to develop mechanisms appropriately designed
for computer-computer communication.
SYSTEM INTERCONNECTION, AN APPROACH
The goal I would like to see us move toward is to view all systems on
the network as offering certain service modules, any subset of which
can be combined in building other systems. Each service module would
have a well advertised set of primitive service capabilities that it
could provide. It would have documented commands at the level of
present Telnet or FTP commands for gaining access to its services.
It would also have a defined network connection procedure. Then any
system builder wanting to avail himself of these services could do so
and integrate them into his own user interface environment.
At the present time when a system is built, the system builders tend
to see it as a stand alone thing or at most something to be used
within a specific environment. What I would like to see fostered is
the idea that any system built is not only a stand alone environment
but also a network service or set of services. The builders would
define not only a user interface for their environment, but also a
set of primitives and primitive commands that can be accessed by
other systems around the network to get that service performed.
For example, we are redesigning the NLS Journal in light of our
experience and that of Network Mail as a set of protocols and
services. If one looks at the processes of the NLS Journal one
can see a number of separate services that could be provided by
different network sites or combined in varying combinations by a
single site. These being:
Distribution (identification of addressees and maintainance of
the required data bases being a related service), recording
(numbering and storing of items), cataloging, and retrieval.