Cisco Cisco Expressway Maintenance Manual
About Call Policy
You can set up rules to control which calls are allowed, which calls are rejected, and which calls are to be redirected
to a different destination. These rules are known as Call Policy (or Administrator Policy).
to a different destination. These rules are known as Call Policy (or Administrator Policy).
If Call Policy is enabled and has been configured, each time a call is made the Expressway will execute the policy in
order to decide, based on the source and destination of the call, whether to:
order to decide, based on the source and destination of the call, whether to:
■
proxy the call to its original destination
■
redirect the call to a different destination or set of destinations
■
reject the call
Note:
when enabled, Call Policy is executed for all calls going through the Expressway.
You should use Call Policy to determine which callers can make or receive calls via the Expressway.
Configuring Call Policy
The Call Policy configuration page (Configuration > Call Policy> Configuration) is used to configure the
Expressway's
Expressway's
Call Policy Mode
The Call Policy mode controls from where the Expressway obtains its Call Policy configuration. The options are:
■
Local CPL: uses locally-defined Call Policy.
■
Policy service: uses an external policy service.
■
Off: Call Policy is not in use.
Each of these options are described in more detail below:
Local CPL
The Local CPL option uses the Call Policy that is configured locally on the Expressway. If you choose Local CPL you
must then either:
must then either:
■
through the Call Policy rules page (Configuration > Call Policy > Rules) — note
that this only lets you allow or reject specified calls, or
■
that contains CPL script; however, due to the complexity of writing CPL scripts you
are recommended to use an external policy service instead
Only one of these two methods can be used at any one time to specify Call Policy. If a CPL script has been uploaded,
this takes precedence and you will not be able to use the Call Policy rules page; to use the page you must first delete
the CPL script that has been uploaded.
this takes precedence and you will not be able to use the Call Policy rules page; to use the page you must first delete
the CPL script that has been uploaded.
If Local CPL is enabled but no policy is configured or uploaded, then a default policy is applied that allows all calls,
regardless of source or destination.
regardless of source or destination.
The Policy service option is used if you want to refer all Call Policy decisions out to an external service. If you select
this option an extra set of configuration fields appear so that you can specify the connection details of the external
service. See
this option an extra set of configuration fields appear so that you can specify the connection details of the external
service. See
.
Configuring Call Policy Rules Using the Web Interface
The Call Policy rules page (Configuration > Call Policy > Rules) lists the web-configured (rather than uploaded via a
CPL file) Call Policy rules currently in place and allows you to create, edit and delete rules. It provides a mechanism
to set up basic Call Policy rules without having to write and upload a CPL script.
CPL file) Call Policy rules currently in place and allows you to create, edit and delete rules. It provides a mechanism
to set up basic Call Policy rules without having to write and upload a CPL script.
You cannot use the Call Policy rules page to configure Call Policy if a CPL file is already in place. If this is the case,
on the Call Policy configuration page (Configuration > Call Policy > Configuration) you will have the option to
on the Call Policy configuration page (Configuration > Call Policy > Configuration) you will have the option to
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Cisco Expressway Administrator Guide