# Advanced Analog Networking Description

Advanced Analog Networking (AAN) provides calling line identification and travelling class marks across T1/D4 trunks. This feature enhances the functionality of systems connected to each other by tie trunks or ISDN trunks.

On tie trunks, the AAN feature provides the following functionality:

- Calling party identification

- Travelling class marks (COS/COR)

- Centralized Station Message Detail Recording (SMDR).

To provide these features, the system outpulses the following information elements: caller's prime line number, caller's dialed or default account code, and the primary node ID of the system. These elements can be outpulsed in any order either before or after the routing digits of a call. The elements can be outpulsed individually or combined in any order.

On ISDN trunks, the AAN feature allows system account digits to be outpulsed in B-channel (DTMF signal) after an ISDN call has been initiated in D-channel and a call progress message (bond tone) has been returned from the CO (see the Account Codes over ISDN example).

## Conditions and Feature Interactions

If a call is routed across the advanced analog network (AAN) either through DNIS digit call routing, or through direct non-dial-in answer-point routing, the ANI number is sent as the calling line identification across the AAN. If an ANI/DNIS call is transferred across the AAN, the ANI number is not sent.

## Account Codes

Account codes capture system resource usage, manipulate system resources, and create call billing records. The types of account codes that can be used are:

- Account Codes - Default

- Account Codes - Non-verified

- Account Codes - Verified.

## AAN-Supported Trunks

AAN is supported only on trunks that use DTMF signaling (including tie trunks). AAN is also supported through central offices over DISA type trunks.

## End-to-End Analog Network

Any account code or caller's extension number received on an incoming system, can be outpulsed to an outgoing system in a tandem or multi-hop call situation. When used in such a way, the AAN feature provides an effective end-to-end network service.

NOTE: Verified account codes used in an end-to-end analog network, must be entered in the Independent Account Codes form of the receiving (or verifying) system.

## Framing Information Elements

Systems frame the information elements used by the AAN feature by prefixing them with the appropriate feature access codes and terminating the information with a "#" character. Incoming systems use this information to identify and interpret the information elements within the frame.

## Traveling Class Mark

Traveling class marks are achieved by outpulsing a user's dialed or default account code prefixed by the AAN account code marker or by using a trunk with a Forced Verified Account Code. The system on the incoming side verifies the incoming account code and uses the COS/COR associated with the incoming account code to handle the call.

Related Topics

- Advanced Analog Networking Conditions

- Advanced Analog Networking Programming