ABSTRACT: This document replaces TA-NWT-000578 and TR-TSY-000578.

This Generic Requirements document (GR) provides the Telcordia view of proposed generic requirements for a Stored Program Control System (SPCS) to provide the Usage-Sensitive Three-Way Calling (USTWC) feature.

USTWC is a SPCS feature that allows a residential customer engaged in a stable two-party call to break out of the call, add a third party to the conversation, and be charged on a per-usage basis. No access code is required prior to establishing the original two-party call, allowing customers to add a third party to an established call at any appropriate time, without advance planning.

As determined by the Local Exchange Carrier (LEC), the customer may be billed for a USTWC in any of the following ways:

• An activation charge each time the USTWC customer reconnects to the first leg of a call after having completed dialing (e.g., the second leg has been answered or dropped) on the subsequent leg
• A charge for the duration of time the three parties are connected
• Each "leg" of the Three-Way Call (TWC) is charged as a normal two-party call at the existing rate (e.g., free calling area, flat rate, message units, intraLATA toll, interLATA toll, etc.).