Our landline terms glossary is designed to explain terms and phrases regarding business landlines.

Select the term to expand on the explanation:

  1. Auto-Attendant

    Auto-attendant is a service that allows callers to be automatically transferred to an extension without the need of an operator or receptionist using extension numbers or voice prompts. Many auto-attendants include a greeting such as “Thank you for you calling X, if you know the extension you require please dial Y” and other auto-attendants may also use a simple menu system to handle calls (“Press one for sales, press two for service” etc.)

  2. Battery Back-up

    Battery back-up comes in two different forms. The initial form is where programming settings (e.g. the date and time) of a phone system are kept safe in case of a mains power failure by use of a small battery. In this case the phone system may not continue to operate in case of power failure. The second form is where the phone system uses a larger battery so the phone system can continue to be used temporarily in the event of a mains power failure.

  3. Call Barring

    The ability to prevent calls to certain destinations, e.g. to foreign countries or calls to premium (0906) numbers.

  4. Caller ID or CLIP

    Caller ID (caller identification, CID) or calling line identification presentation (CLIP) is a service that displays the phone number of the caller on the answering phones screen display. Caller ID (also known as CLIP) also has a feature called alpha tagging, which can show the caller’s name and company if available.

  5. Call Forwarding

    Call forwarding (or call diversion) is used to divert incoming calls from one telephone number to another telephone number. For example the destination number may be a different extension, the operator or a mobile phone.

  6. Call Management

    Call management is usually software that runs on a PC or Mac that’s used to analyse call records and telephone usage.

  7. Call Park

    Call parking is where a call is put on-hold (or ‘parked’) by one user of a phone system for retrieval by another user.

  8. COLP – (Connected line presentation)

    COLP (connected line presentation) is a service that allows you to view the number to which your outbound call has been connected to when possible. This may not necessarily be the number that was initially dialled.

  9. Conferencing

    Call conferencing is where three or more users are connected together in a single phone call.

  10. CPS – (Carrier Pre-Selection)

    Carrier pre-selection (CPS) is a service that allows customers to select (in advance) an alternative communications company from their existing supplier to handle their calls without having to dial a prefix or install any special equipment. The customer subscribes to the services of a CPS operator and chooses the type of calls (e.g. any national calls) to be handled by them. This gives the customer the flexibility of cheaper call rates without a change in hardware supplier. The customer is then billed for these calls separately by the CPS operator or a CPS reseller.

  11. DECT – (Digital Enhanced Cordless Technology)

    DECT (digital enhanced cordless technology) is the modern standard for cordless phone technology. Used primarily in homes and small office environments, but also available in many PBX systems for medium and large businesses.

  12. Delayed Ringing

    Delayed ringing is a useful feature if the switchboard operator is busy or absent. Incoming calls go to an operator first, but other extensions may have delayed ringing enabled, so they will only start ringing if the call is not answered after a pre-set time.

  13. DDI – (Direct Dial Inwards)

    DDI (direct dial inwards) or DID (direct inward dialling) is a service where individual phone numbers (or DDI numbers) can be applied to employees and departments without requiring a separate physical phone line for each. These DDI numbers are associated with one or more existing phone lines instead and are only available on digital lines such as ISDN 2.

  14. Group Ringing and Hunt Groups

    Group ringing is where a group of extension numbers can be dialled by a single telephone number at the same time. The group may be set up as a ring group, in which case all extensions ring at the same time , or it may be set as a Hunt Group. A Hunt Group is where the phone system will find a free extension within a group of numbers to take the incoming call.

  15. ISDN – (Integrated Services Digital Network)

    ISDN stands for Integrated Services Digital Network. ISDN is a digital solution integrating speech and data (e.g. internet use) on the same line, adding features that are not available on a classic telephone system.  Designed to allow digital transmission of voice and data over ordinary telephone copper wiring, resulting in potentially better voice quality than a classic analogue phone system.  There are multiple types of ISDN available including ISDN 2 which gives you voice and data access from two to eight users, along with ISDN 30 which provides voice and data access from eight to thirty users.

  16. Live Call Screening

    Live call screening is a feature available on some voicemail systems where a user is able to listen to a caller leaving a message, and be able to answer the call if required.

  17. Night Service

    Most modern telephone systems have two operating modes, Day service and Night service. These different operating modes decide where incoming calls are diverted to (e.g. a voicemail box after working hours.) Night service may also provide the option with certain call barring features to prevent unauthorised use of the phone system outside of working hours by security or cleaning staff.

  18. PSTN – (Public Switched Telephone Network)

    PSTN or analogue is the classic telephone system using a standard phone line, with a single line allowing one call (inbound or outbound) at a a time. These types of lines are also commonly used with credit card machines, fax machines and post franking systems. Using a microfilter on each telephone socket, standard PSTN lines can also be split into data/broadband and voice connections using ADSL broadband. Meaning that telephone calls can be made at the same time as accessing the internet.

  19. SIP (Session Initiation Protocol)

    SIP (session initiation protocol) is a similar technology to VoIP but provides you with the ability to simulate a conventional telephone network over the internet without requiring a PC or tablet. Outgoing calls can be made into all networks and incoming calls can be received from landlines as well as mobile networks. Furthermore because SIP is an open system, it has greater support worldwide and many existing phone systems can be used on a SIP network with a few modifications.

  20. Trunk

    A trunk is a line connecting one phone system to another phone system or to the PSTN (public switched telephone network).

  21. VoIP – (Voice over IP)

    VoIP (Voice over Internet Protocol) is voice and sometimes video calling using the internet rather than a standard analogue phone system. VoIP is available on many modern smartphones, PC’s, tablets and on Internet access devices. Although standard VoIP connections are limited and dependent on factors such as internet speed and cost per call to standard landlines.