Tele-Communication (Telecom) Terms Glossary and Dictionary
800 Service generally refers to the toll free services including 800, 888, 877, 866 number services that former AT&T, MCI, Sprint and the Bell operating companies used for so called IN-WATS service. Those 800, 888, 877, 866 numbers in the dialing plan are served as "area code" by analogy with normal telephone dialing plan. Dialing of 800 service is free to the person making the call. However the call is billed to the person or company being called. 800 calls can terminate on any telephone or cell phone with their own normal telephone numbers. This is a way to charge the called parties who have their own "normal" phone number and subscribe to the 800 service so that the calling party can be free of charge. This 800 service is basically a database lookup and translation service for incoming phone calls. The 800 service works like this: If a 800 number dialed, which means a 1-800 plus seven digits, the LEC (Local Exchange Carrier, i.e. the local phone company) central office sees the "1" and recognizes the call as long distance. It ships that call to a next level or a bigger central office depending on where the routing information is stored. The processing central office recognizes the 800 "area code" and examines the next seven digits. At this point, the LEC switch holds the call, while it queries a centralized database, usually over a SS7 (Signaling System 7) link. That centralized database identified the LEX or IXC (Inter Exchange Carrier) providing the 800 number, as well as translating the 800 number into a "real telephone number". Based on that "real telephone number", the LEC switch will then route the call to the proper IXC (long distance company). Once the long distance company has the 800 call, there are many way it can send the call to the the phone it's intended for.