ABSTRACT: This document contains the view of Telcordia on the proposed generic requirements for the interface to an external Real-Time Rating System (RTRS). The purpose of the interface described in this document is to unbundle real-time rating functionality from the Operator Services System (OSS). While the focus of the document is on OSS access of the RTRS, any system following this interface could potentially access the RTRS. The interface supports real-time rating for the following types of services: Traditional Coin, Intelligent Public Access Platform, Busy Line Verification/Interrupt, Directory Assistance, Directory Assistance Call Completion, Rate Quotation, Time and Charges, and Notify.