2.1 SoR Application Overview

The SoR application lets home network operators control and distribute registration traffic of their outbound roamers. Use SoR to define static distribution roaming steering policies for each group of roaming partners that are part of the same country.

SoR is deployed as a roaming management solution intended for optimizing roaming cooperation between operators. It allows flexible network selection management for outbound roamers to stimulate an appropriate roaming network choice for subscribers.

For each roaming partner providing service in a given country to the home network's outbound roamers, the home network can define the following:

• Static proportion of successful registrations
• Proportion of successful registrations in the network over a specified period of time
• Minimal allowable threshold for successful registrations over a specified period of time

SoR tracks the number of times a given subscriber was rejected in a certain (configurable) time window, and if the number of registration attempts exceeds a certain count (also configurable) within the time window, the Request is allowed for further processing by the DSR irrespective of the VPLMN. To assist with the allow and reject decisions, the SoR can rely on the configuration in addition to maintaining the number of rejections and the time window.

The SoR application is configured as the owner of a UDR database. To avoid overloading the SoR application, the Application Routing Table (ART) is configured in such a way so as to route only ULR messages to the SoR application that include an Origination-Realm that does not match the realm of the home MNO.

The SoR application can be enabled and disabled as a DCA Framework application. Disabling SoR on a specific site is possible only if SoR has been disabled on all the DA-MPs on that specific site. SoR can be completely configured at the NO.

DCA Framework allows for the creation of applications on top of the Diameter Signaling Router (DSR), allowing for a faster development cycle. There can be up to 10 versions of each Diameter Custom Application in the various states.

To use the SoR application for DCA, the DCA Framework must be activated on the NO. Activation needs to be performed only once. See the Diameter Custom Applications Feature Activation Guide for instructions about activating DCA Framework.

When the SoR application is initially installed, it is disabled, and you must manually enable it. To do so, navigate to Diameter, and then Maintenance, and then Applications and enable the application for every DMAP using SoR.

If SoR is in the DCA Framework GUI menu, this means that the application is already enabled, but does not guarantee that it is provisioned. You can also disable SoR from the Diameter, and then Maintenance, and then Applications.

DCA Framework applications functionality varies between the SO and NO; for example, System Options is available on the SO only.