Understanding SRX Series Integrated Convergence Services Media Gateway Trunks

When the peer call server is in control, it routes calls from the branch using its own telephony trunks. It can also route calls out SRX Series media gateway (SRX Series MGW) trunks at the branch, if required and any are configured.

To use SRX Series MGW trunks, you must configure them and a dial plan that specifies one or more route patterns to include the trunks.

In many ways, SRX Series MGW trunks are defined similarly to trunks for the SRX Series survivable call server (SRX Series SCS):

• They are included in trunk groups, which, in turn, are included in route patterns.
• Each trunk group must include at least one trunk.
• If a route pattern contains multiple trunk groups, you can give each one a preference number indicating the order in which it is tried to route a call. If you do not use preference numbers, trunk groups are tried in the order in which you add them to the route pattern.

Route patterns for SRX Series MGW trunks and dial plans differ from SRX Series SCS trunks and dial plans in the following ways.

For the SRX Series MGW:

• The digit pattern of a route pattern specifies a trunk access code. Called numbers that have a trunk access code prefix matching a route pattern’s digit pattern are routed through one of the trunks specified for the route pattern.

  Trunk access codes allow the peer call server to route calls through specific trunks, not based on the call type.

• The call type for a route pattern is always “trunk-call”. You do not differentiate types of calls, such as long-distance and international calls, as you do for SRX Series SCS route patterns.

For example, suppose the peer call server administrator wants to use SRX Series MGW trunks to route some calls out a PSTN trunk and others out a VoIP service trunk.

• To route calls out the PSTN trunk, the administrator might define a route pattern with 6 as its trunk access code. Called numbers with the digit 6 as a prefix are routed out the PSTN trunk.
• To route calls out the Hong Kong VoIP service provider’s trunk, the administrator might define a route pattern with 8 as its trunk access code.

  Called numbers with the digit 8 as a prefix are routed out the VoIP service trunk.

Related Topics

• Understanding Trunk Precedence and Trunk Group Preference for SRX Series Integrated Convergence Services
• Understanding Integrated Convergence Services Media Gateway Trunks and Dial Plans
• Understanding Trunk Group Reusability for SRX Series Integrated Convergence Services
• Understanding Trunk Reusability for SRX Series Integrated Convergence Services
• Example: Configuring an Integrated Convergence Services Media Gateway and Trunks