110916 NOTAIL.MAC Version: 8A, September 1991
Submitted by: Billy Youdelman, Consulting Electrical Engineer
Operating System: TSX-PLUS V6.31 Source Language: MACRO-11 Memory
Required: 1KB Software Required: MACRO-11 for assembly, program must
be edited for site requirements then assembled and linked. Keywords:
Emulators, Security, TSX-PLUS
Abstract: Tailgating is the name commonly given to what happens when a
modem data path is broken before the job using it has logged
off, and the next call is connected to that still active
session of the prior user.
TSX-PLUS was given improved modem control in V6.40, with
which tailgating incidents are easily prevented. If you are
using TSX-PLUS V6.40 or later, then this program is not
necessary. In either case, the information concerning
use of a logoff command file applies.
If you are using TSX-PLUS V6.31 or earlier, the TIMOUT value
which governs how long a job will be held active after the
data carrier has been lost, determines the time allowed for
a caller to first connect, type two returns and initialize
the line. Thus setting TIMOUT small enough to prevent
tailgating means its not likely anyone will be able to
log on a phone line either.
This little program, running as a detached job, checks
designated lines every 0.5 second and kills any that may
still be logged on without DCD held true.
Changes and Improvements: Extended to work with Operating system
TSX-PLUS V6.0 through V6.31.
Restrictions: Operating system TSX-PLUS V6.0 through V6.31 is
Media (Service Charge Code): One RX01 Diskette (KA) Format: RT-11,
600' Magnetic Tape (MA) Format: RT-11
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Created: December 26, 1998