Table of Contents:

Definition and Overview

1. Overview of Access Mediation and Access Gateways

2. Access Mediation Example

3. Access Gateway Example

4. Application Scenarios I: User-Network Interface and Telephone Switch Trigger Control

5. Application Scenarios II: Call Waiting with Internet Enhancement

6. Application Scenarios III: Shared Subscriber Information and Call/Connection Control Across Networks

7. Access Mediation: Platform Functional Requirements

8. Summary

Glossary

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Specific to telephony-based applications of access mediation is the need for a mediation point in the AIN SS7 signaling network. The mediation point allows the interconnection of SS7 networks owned and operated by different telephone service providers. By interconnecting the SS7 networks, AIN query messages that originate on one provider's network can pass to another provider's network. On the second network, the query messages can reach an AIN service control point (SCP) where they will be processed by AIN applications, and appropriate AIN response messages will be returned. As a result, a customer receiving basic telephone service from one provider's network can subscribe to and utilize AIN service offerings available on a second provider's network. Figure 2 illustrates how a mediation point handles AIN signaling associated with this example.

Figure 2. Access Mediation Example

As shown in the figure, numbers indicate the chronologically ordered path of the IN message. IN message is indicated by numbers. The following text describes the message flow:

1. The AIN trigger is detected, and a query is launched to the basic service provider's service transfer point (STP).
2. Based on global title translation, the basic service provider's STP forwards the AIN query to the mediation point.
3. The mediation point receives the AIN message. Mediation is then performed. The mediation functionality can include network element screening, network message screening, parameter screening, overload controls, and destination selection. As an example, destination selection can be based on SCP data or on more sophisticated data such as TCAP parameters (e.g., ten-digit calling/called party number or trigger criteria type). Acting as a proxy, the mediation point forwards the AIN query to the alternate service provider's SCP destination point code via the basic service provider's STP.
4. The basic service provider's STP receives the AIN query message and forwards it to the alternate service provider's SCP.
5. The alternate service provider's SCP receives the AIN message, performs the appropriate AIN functionality, and sends the response message back to the basic service provider's network.
6. The basic service provider's STP receives the AIN response message and sends the message back to the mediation point for additional mediation functionality, such as network element screening, message and parameter screening, and billing.
7. The mediation point forwards the response message back to the basic service provider's STP.
8. The basic service provider's STP in turn sends the message back to the basic service provider's service switching point (SSP) for final AIN treatment.