Overview of the BNU processes
Most tasks associated with
Basic Networking Utilities administration may be performed using either
the menu system or shell commands entered on the command line.
There follows a general description of the BNU process.
The phases are marked on the diagram that follows.
Phase A-
A user on the local machine issues a command requesting file
transfer or remote execution communication with a remote computer
(phase A).
Several
BNU
database support files are read to determine if the remote
computer is accessible by the local computer and the priority
of the user's request compared to other users' requests.
This phase ends by queuing the user's request in a spool
area on the local machine and triggering the next phase.
Phase B-
The uucico routine is triggered automatically (phase B).
It reads several
BNU
database support files to determine
when the remote computer can be reached, how to establish the
link to the remote computer, how to handle data flow
between the local and remote computers, and the maximum
number of simultaneous requests for communication to the
remote computer.
Phase B'-
The uucico routine calls the connection routine,
dials(3N),
and passes the request and associated information to the
server.
Phases C and C'-
The uucico routine on the remote computer is
triggered automatically when a call for communication is
received from the local computer (phase C).
In this phase, the remote
uucico routine reads
BNU
database support
files on its computer to determine if the calling computer is
allowed access, and what action to take if the calling
computer is not allowed access (phase C').
For calling computers
that are allowed access to the remote computer, the level of
access is determined in this phase.
Phase D-
Requests initiated on the local computer may contain commands
to be executed on the remote computer (phase D).
When these commands
arrive on the remote computer, they are stored in a spool area.
During this phase, the remote uuxqt routine
runs these commands on the remote computer.
Basic networking process diagram
© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 22 April 2004