Roaming
Facility offered by the mobile phones of the GSM system to make and receive calls in other countries than the country in which the service was registered.

RJ11, RJ45
Small plastic connectors with a locking function that come in two sizes, with 6 and 8 pins respectively. The smaller connector is used for telephony, while the larger is used for ISDN and 10Base-T connections.

Router
Network function responsible for forwarding data packets from their origin to their destination.

Reverse Charge Tariff
The case when the call is paid for by the called party.

Regional Area
A geographical area or a specific tariff zone comprising an important district capital, including its surroundings.

Regulatory Body
An organization created by the State that has legal competence to regulate and monitor the telecommunication activity in a system of competition, and to ensure the management of the radio-electrical spectrum.

Registry
The information that defines and identifies the installation of equipment.