Symbolic usernames and RFS

[Wayne Hathaway]

We (Informatics General Corp, currently undergoing renaming
to Sterling Software) have implemented a Newcastle-based
remote file system on various flavors of System V for NASA's
Numerical Aerodynamic Simulation Project.  (I say Newcastle-
based because although the ideas are Lindsay's, we have done
a lot of rewriting and shoehorning.  Lindsay should get the
credit for Good Things, Bad Things should be blamed on us.)

The code currently connects IRIS workstations, VAXen, and a
Cray 2; it will soon be put on two Amdahl mainframes.  (And
by the by, the underlying networking is provided by our ports
of enhanced 4.2BSD code into the various systems, except for
the Amdahls where Wollongong's port is currently being used.)

We saw from the beginning (thanks, Lindsay) the need for a
uid/gid mapping mechanism, and have implemented what we feel
to be a flexible, high performance one.  We also added the
concept of machine-id to provide a single identifier (number)
for each machine, so that mappings are truly based on machine
and not on something like Internet address (which is in fact
the PATH to the machine).  In the NASA network, essentially
every machine is on both a HYPERchannel and an Ethernet, so
the use of machine-id cuts the mapping files in half.

About the only difference I see between our mapping scheme
and the one in the Eighth Edition is that we have an explicit
default mapping defined, so that (for example) a workstation
could have unknown uid's map to "guest" while the mass storage
system might reject unknown uid's entirely.

As they say, for more information contact ...

	Wayne Hathaway
	Infor -- oops, Sterling Software (Informatics)
	415-964-9900
	wayne at ames-nas.arpa