Intelligent Network (IN) is a telephone network architecture originated by Bell Communications Research (Bellcore) in which the service logic for a call is located separately from the switching facilities, allowing services to be added or changed without having to redesign switching equipment. According to Bell Atlantic, IN is a "service-specific" architecture. That is, a certain portion of a dialed phone number, such as 800 or 900, triggers a request for a specific service. A later version of IN called Advanced Intelligent Network (AIN) introduces the idea of a "service-independent" architecture in which a given part of a telephone number can interpreted differently by different services depending on factors such as time of day, caller identity, and type of call. AIN makes it easy to add new services without having to install new phone equipment.
Bellcore called its network IN/1. It included this model:
- The customer's telephone
- The switching system (starting with the switch a call is handled by first, usually at a telephone company central office (CO)
- A database called a service control point (SCP) that defines the possible services and their logic
- A service management system (SMS)
For more information, see AIN.