Re: Ada using the Internet for multi-tasking

[johndoe@inmet.UUCP (johndoe )]

In article <1991Mar25.150213.1@elcgl.epfl.ch> madmats@elcgl.epfl.ch writes:
>In article <366@platypus.uofs.edu>, cml8@robin.cs.uofs.edu (Chris M. Little) writes:
>Of course, several instances of an Ada program have to run and make up a
>distributed application (actually distributing tasks over such a network would
>not be feasible because of data shared by tasks and access types among others.
>Moreover, it would require modifying an Ada compiler or run time system).

There is the possibility of using CAIS-A (Common APSE Interface Set)
technology of doing distributed computing over a single network.
Currently, the CAIS-A distributed implementation is a set of interfaces
that allows access to the common database through a main server
coordinating activity and a set of local_servers - one per machine.  For
a set of client Ada programs running on different machines, communication
is accomplished via CAIS-A interfaces for I/O and database access.  The
client programs would refer to one another, as well as to the communication
gateway and channels, with entities associated with the database.  This
requires no changes to a compiler or run-time system for a networked
Ada application.

Of course, at this point, it would have to be a network of Sun3
computers, since the only currently available distribution of a CAIS-A
implementation is for targeted to Sun3 architecture.  And for the time
being, you couldn't compile it, because the only supported compiler is
made by Systeam, who are now a subsidiary of Alsys, and who don't really
have a compiler product per se.  However, this should be changing in the
near future with a VMS version of a CAIS-A allowing distributed
processing, and support for the Telesoft compiler on Sun3, and the
Systeam and DEC compilers for the VAX.

For more information about CAIS-A, contact me (johndoe@inmet.inmet.com), or
Barry Siegel of NOSC (siegel@tecr.nosc.mil).