1. Diameter Signaling Router Mobile Number Portability User Guide
  2. Mobile Number Portability Feature Description
  3. G-Port MNP Overview
  4. G-Port Functions

G-Port Functions

G-Port involves these main functions.

Message Discrimination

Since G-Port is currently only used for translation of ported numbers. It provides a method to identify which messages should receive G-Port versus GTT. This is provided usinga service selector table where one can define the G-Port service for a combination of selectors. If a selector match is not found, then G-Port falls through to GTT.

Number Conditioning

Since the UDR NPDB stores International MSISDNs only, G-Port provides the capability to condition incoming numbers to be international MSISDNs (for example, delete routing number prefix or insert CC or/and NDC ) for the database lookup. Also, messages with a ported-in number in SCCP CdPA or MAP MSISDN might have an RN prefix. G-Port strips the RN prefix and conditions the non-international numbers to international numbers, if needed, before performing a database lookup.

SRI Response

When the incoming SRI message does not already contain an RN in the SCCP portion, or if the VstpMnpOption:MNPCRP is Off, G-Port generates an SRI Ack message for an SRI message when the number is a foreign number and an RN is associated with the DN in the database. When neither an RN nor SP is associated with a MSISDN in the database, G-Port formulates an SRI Ack message ONLY for null PT or foreign number PT. For all other cases, the SRI falls through to the GTT. When formulating an SRI Ack message, G-Port uses the RN prefix associated with the MSISDN entry to build the MSRN number or, based on the VstpMnpOption:MSRNDIG to not prefix, returns the RN only. G-Port generates a negative SRI Ack message when encountering any MAP SRI problems. If VstpMnpOption:MNPCRP is On and the SRI message already contains an RN in the SCCP portion or MAP MSISDN, then G-Port issues Event #70304 and the message falls through to the GTT. Since the CdPA/MAP MSISDN contains RN+DN, this should result in a GTT failure, which causes a UDTS to be returned to the originator if the Return Message on Error flag was set in the incoming UDT. If MSISDN is provisioned in UDR NPDB with PT values of 0/1/2 (foreign number), the SRI response has an NPS value of 0/1/2. When the PT value is defined as null, it is mapped to an NPS value of (0) in the SRI response.

G-Port Message Relay

G-Port performs message relay on non-SRI or SRI-SOR (SRI messages with OR Interrogation Indicator present) messages when the MSISDN number is ported. Message relay provides an ability to prefix the routing number to the CdPA digits or replace the CdPA digits with an RN prefix based on the digit actions. If VstpMnpOptions:SRISMGTTRTG is On, then the SRI_SM and ReportSMDeliveryStatus messages are not relayed. Instead, the CdPA GTA in the message is modified in CC+RN+DN format (or RN+IDN format if the CC match is not found in leading digits). The NAI of CdPA GTA is set to International and the message falls through to the GTT.

Message Relay on Ported-In Numbers

G-Port automatically performs SCCP relay on SRI and non-SRI messages for its own numbers (for example, an SP is associated with the DN in the database). However, the non-ported (PT=4) or ported-in (PT=5) entries should be present in the UDR NPDB and SP entity should have been defined for this entry. This applies even in the case when VstpMnpOptions:MNPCRP is On and the message contains an RN in the incoming SCCP. If GRN is also associated (along with SP entity) with the DN and the GRN is not present in the HomeRN table and S VstpMnpOptions:SRISMGTTRTG is On, then the SRI_SM and ReportSMDeliveryStatus messages are not relayed. Instead, the CdPA GTA in the message is modified in CC+GRN+DN format (or GRN+IDN format if CC match is not found in leading digits). The NAI of CdPA GTA is set to International and the message falls through to the GTT.