NTSC means NSIC-Technical Services Centre
Mobile Network means the network facilities and/or network services comprising the public cellular network for the provision of Call Communications.
LRN means a unique ten- (10)-digit number assigned to a Central Office Switch in a defined geographic area for call routing purposes. This ten- (10)-digit number serves as a network address and the routing information is stored in a database. Switches routing calls to subscribers whose telephone numbers are in portable NXXs perform a database query to obtain the Location Routing Number that corresponds with the Switch serving the dialed telephone number. Based on the Location Routing Number, the querying Carrier then routes the call to the Switch serving the ported number. The term "LRN" may also be used to refer to a method of LNP. "Long Distance Service" (see "Interexchange Service").
Network User means a customer or a potential customer of a transmission system operator, and transmission system operators themselves in so far as it is necessary for them to carry out their functions in relation to transmission;
PSTN means the public switched telephone network.