Prepaid IDP Query Relay Overview

IDP Relay processes GT-routed INAP or CAP messages with ITU MTP/SCCP/TCAP parts and Opcode=IDP.

IDP Relay provides functions that handle complex numbering schemes and number conditioning, such as the following examples:

• The Nature of Address Indicator (NAI) could be used in a non-compliant manner (the NAI is set to International and the number format is not international).
• The Local Area Code (LAC) 2- byte field of the Local Area Identification (LAI) information element is used in one of the following ways:
  • As the Area Code in cases where the AC is needed but not provided in the CdPN
  • To determine how to format the outgoing CdPN in the IDP query
• The collect call Escape Codes 90 and 90909 might need to be stripped and re-inserted after the RN.
• The Carrier Selection Point (CSP) can be removed from the incoming number and sometimes re-inserted (as when the LAC is not equal to the AC).
• The RN for the CgPN might be needed when the call is identified as a collect call.
• Service Key selection could vary, and could require a change in the number of bytes present the Service Key.
• Unsegmented XUDT messages might be required.
• Sometimes the RN but not the SP, or the SP but not the RN, or both the RN and SP are required in the outgoing number format.

When Mobile Switching Centers (MSCs) in the network are configured to send IDP prepaid query messages through vSTP, the vSTP intercepts the IDP query based on a set of configurable criteria, performs a number portability (UDR) lookup on the called number, inserts the portability information (Routing Number or HLR Address), and forwards the IDP query to a prepaid SCP for processing. When a respective entry is found in the UDR, any processing is controlled by NPP Service Actions and configuration option provisioning in the IDPROPTS table. The CdPN can be modified with the portability information (Routing Number or HLR address) and the CgPN.

In standard IDP Relay processing, regardless of any actions performed on the IDP query by the IDP Relay feature, the query is always forwarded to the prepaid SCP (PPSCP) for processing.When the SCP receives the IDP query, all information necessary for call processing and billing is present. The IDP Relay feature alleviates the need to launch a separate number portability database query.

IDP Relay also provides the following functions:

• CONNECT, CONTINUE, or RELEASECALL responses - Provisioning can allow CONNECT, CONTINUE, or RELEASECALL responses to be sent based on the UDR lookup results. A configuration option determines whether the CutAndPaste parameter is included in a CONNECT message that is sent from the Prepaid IDP Query Relay feature.
• Service Key-based GTA Routing (SK GTA Routing) - A provisioned Service Control Point (SCP) Global Title Address (GTA) value based on the Service Key can be used to replace the SCCP Called Party Address (CdPA) GTA in a message. This allows the IDP or IDPSMS message to be GTT routed to the provisioned SCP GTA instead of to the incoming SCCP Called Party Address (CdPA) GTA.

Number Portability Types

IDP Relay supports the following types of Number Portability:

• Provider NP - the subscriber can move to another service provider and keep the same number
• Location NP - the subscriber can move to another location within the same service provider network and keep the same number

  This manual describes Provider NP and Location NP together as "NP".