SoR Message Acceptance and Rejection Logic

When receiving a ULR message, SoR determines whether the message should be accepted or rejected. Accepting a ULR means that the message is forwarded for further processing on the DSR MP and possibly later to the HSS. Rejecting a ULR sends back a ULA message.

Accepting or rejecting a message depends on the conditions described in Table 1.

Message Accept or Reject Criteria
Condition	Description
vMNO status	If the ULR is coming from a vPLMN that belongs to a vMNO with non-preferred status from some country, then the message should be accepted only if none of the preferred vMNOs for that country has not received its defined share of traffic yet. A ULR coming through a vPLMN belonging to a preferred vMNO is always accepted.
vMNO share	In case of non-preferred MNOs, whether a ULR should be accepted or not depends on the number of successful registrations already served by the vMNO.
Registration history	Subscribers re-registering after a successful registration through some vMNO should be allowed to register through the same vMNO again regardless whether this vMNO has received its share. Furthermore, the number of registration attempts must be limited so as not to prolong the registration period indefinitely.

SoR collects the information described in Table 2 to determine whether to reject or accept a ULR message.

Data Collected by the SoR Application
Value	Description
Traffic distribution	Collect information about the distribution of successful registrations. An arrayed custom measurement is created with an entry for each MNO configured in the roaming steering profile. An arrayed custom measurement for MCC is created with an entry for each MCC configured in the roaming steering profile.
Subscriber ULR Handling	SoR maintains (per subscriber) records that indicate the following data: Total Rejections How often was the registration of this subscriber rejected Last rejected MNO Identity of the MNO to which the MCCMNC indicated in the last rejected ULR message of this subscriber belongs to. Last accepted vPLMN Identity of the MNO to which the MCCMNC indicated in the last accepted ULR message of this subscriber belongs to.