Jargon buster

Calling Line Identity Restriction (CLIR) is when the telephone number is withheld from the call recipient.

A carrier is a telecommunications service provider that owns their own network, e.g. BT or Gamma.

Carrier Pre-Selection (CPS) is the process of routing calls via a service provider’s chosen network.

Category 5 or CAT5 (or CAT5e) is the specification for the transmission performance of an ethernet data cable but is frequently used to describe structured cabling routing voice and data circuits to wall sockets within a building. CAT5/5e transmission can be up to 100MHz.

Category 6 or CAT6 is an upgrade to CAT5/5e cable enabling performance of up to 250MHz compared to 100MHz with CAT5/5e. CAT6 is backwards compatible with CAT5/5e ethernet cables.

Category 7 or CAT7 is used for Gigabit Ethernet cabling infrastructure offering transmission performance up to 600MHz.

see Closed Circuit Television

see Central Control Unit

see Call Detail Record

The Central Control Unit (CCU) is the box or cabinet that houses the hardware controlling the telephone system.

Centrex (short for Central Exchange) is a hosted telephony solution providing the functionality of a PBX without the costs and logistics associated with a physical on-premise system.

The ability to give a data packet a series of set properties/restrictions/access levels during a telephone call. E.g. A user can be given a COS value of 1 that permits international dialling while the value of 2 disables this ability.