Administrator's Guide

Remote Access
Issue 5 October 2002 1803555-233-506
Barrier Codes
Remote Access has inherent risks; it can lead to large-scale unauthorized
long-distance use. To increase your system’s security, use a 7-digit barrier code
with Remote Access Barrier Code Aging. You can administer the Remote Access
Barrier Code Aging feature to:
■ Limit the length of time an access code remains valid
■ Limit the number of times an access code can be used
■ Both of the above
You must administer expiration dates and access limits for each of the possible 10
barrier codes. If your system has more than 10 Remote Access users, they must
share codes. A barrier code automatically expires if an expiration date or number
of accesses has exceeded the limits you set. If both a time interval and access
limits are administered for a barrier code, the barrier code expires when one of the
conditions is satisfied.
If barrier codes are administered, a special answer-back tone causes a calling
modem to leave dial mode. A modem’s dialer is sometimes used to gain access
(this tone also cancels echo suppressors in the network, preventing DTMF tones
from breaking dial tone from a switch). Barrier codes can be used alone or with
authorization codes.
To view the status of a Remote Access barrier code, use the status remote-access
command.
NOTE:
Barrier codes are not tracked by Call Detail Recording (CDR). Barrier codes
are incoming access codes, whereas, authorization codes are primarily
outgoing access codes.
When you no longer need a barrier code, remove it from the system. Barrier codes
should be safeguarded both by you and their users.
Authorization Codes
You can also administer authorization codes to manage access to your system.
You can then use CDR to track this code use. Use these guidelines to manage your
system’s authorization codes.
■ Assigning codes — Create random codes; do not allow them to follow a
predictable pattern. Use the maximum code length allowed and assign a
unique code to each person responsible for protecting the code.
■ Changing codes — Change codes often.
■ Deleting codes — Delete codes when they are no longer needed.
■ Monitoring codes — Use CDR reports to analyze code use.