Cisco Cisco Expressway
3. Click Save.
Task 14: Restricting access to ISDN gateways (optional)
Expressway users are recommended to take appropriate action to restrict unauthorized access to any ISDN
gateway resources (also known as toll-fraud prevention). This optional step shows some methods in which
this can be achieved.
gateway resources (also known as toll-fraud prevention). This optional step shows some methods in which
this can be achieved.
In these examples, an ISDN gateway is a neighbour zone that routes calls starting with a 9.
Expressway-E
Two search rules are created on the Expressway-E:
n
both search rules have a pattern string that matches calls directed at the ISDN gateway — in this example,
calls that are prefixed by a 9
calls that are prefixed by a 9
n
the first rule has a Source of All zones; this allows calls from neighbor zones to be passed through to the
traversal zone
traversal zone
n
the second rule is similar to the first rule but has a Source of All; this means that non-registered endpoints
(which are excluded from the previous rule) are included by this rule and can be stopped by defining the
Replace string as "do-not-route-this-call"
(which are excluded from the previous rule) are included by this rule and can be stopped by defining the
Replace string as "do-not-route-this-call"
n
both rules stop any further search rules from being looked at (On successful match = Stop).
To create the search rules:
1. Go to
Configuration > Dial plan > Search rules
.
2. Click New.
3. Configure the fields as follows:
Expressway-E
Rule name
Enter Allow ISDN call for example
Description
Enter Allow ISDN calls for neighbors
Priority
Enter 40
(these rules must be the highest priority in the search rule configuration)
(these rules must be the highest priority in the search rule configuration)
Cisco Expressway Basic Configuration Deployment Guide (X8.2)
Page 31 of 57
Optional configuration tasks