This topic describes the services that GDPR provides and how they relate to globalized call routing.
- Application that uses ILS.
- Supports exchange of URIs and numbered call-routing information.
- Unique route string is associated with each advertising cluster.
- Call routing is based on the route string, not on actually called URI or number.
- A SIP route pattern must be configured for each route string.
- Each SIP route pattern refers to a SIP trunk (directly or via a route list and route group construct).
- Routing can be on an any-to-any basis (full mesh) or hierarchical (e.g., Cisco Unified Communications Manager Session Management Edition).
Each cluster is configured with a unique route string. A route string has the same format as the host portion of a directory URI.
Call routing is based on the received route string of the advertising cluster and not on the URI or number that is actually called.
A SIP route pattern must be manually configured for each route string. Each SIP route pattern refers to a manually configured SIP trunk, either directly or via a route list and route group construct.
The need for manual SIP route pattern and SIP trunk configuration differs from a SAF or CCD, where you only have to configure a SAF trunk, which acts as a template for the dynamically created trunks to the other SAF clients.
GDPR replaces the called destination (URI or number) with the learned route string. You must make sure that you can route calls to that route string.
Routing can be implemented on an any-to-any basis (full mesh of SIP trunks between all participating clusters) or in a hierarchical fashion, for example, by using Cisco Unified Communications Manager Session Management Edition.
Considerations for ILS-Based Numbered Call Routing
When you deploy GDPR for numbered call-routing information, you want to use a globally unique format for the advertised numbers and patterns.
- GDPR works best with a dial plan based on +E.164 numbers (globalized call routing).
- Cisco Unified Communications Manager Version 10 introduced several improvements for globalized call routing:
- Translation pattern for calling search space inheritance
- Interdigit timeout policy for translation pattern secondary lookup
- Multiple local route groups
- Incoming and outgoing transformations and connected-party transformations on all trunks and gateways
- Directory number configuration enhancements:
- Urgent directory numbers
- Enterprise alternate number and +E.164 alternate number
- PSTN failover number
- Possibility to independently advertise alternate (and PSTN failover) numbers via ILS
GDPR for numbered targets also supports PSTN backup. For large deployments, especially when they involve multiple countries and different PSTN access codes, it is strongly recommended to use globalized call routing where the dial plan is based on numbers in +E.164 format.
Cisco Unified Communications Manager Version 10 introduced several improvements for globalized call routing, including the ability to configure a DN with two “aliases”:
- Enterprise alternate number
- +E.164 alternate number
Each alias can be independently configured to be added to the local call-routing table (into a configurable partition) and to be advertised by ILS.
In addition, you can advertise a PSTN failover number via ILS by choosing one of the two aliases to be used as the PSTN failover number.
The recommendation is to use an enterprise-wide format for internal dialing for the enterprise alternate number and +E.164 format for the +E.164 alternate number. Such a configuration allows you to advertise a DN by its enterprise format (for example, with a site code prefix) and by its +E.164 number, which can be used as the PSTN failover number.
When your dial plan uses globalized call routing, you will be able to place PSTN backup calls to ILS-learned destinations without any additional configuration. There is no need for cumbersome, cluster- or site-specific digit manipulation. This digit manipulation is already done by your globalized call-routing deployment.