Cisco Cisco Expressway
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.
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:
■
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
that are prefixed by a 9
■
the first rule has a Source of
All zones; this allows calls from neighbor zones to be passed through to the traversal
zone
■
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"
as "do-not-route-this-call"
■
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.
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Cisco Expressway-E and Expressway-C - Basic Configuration Deployment Guide