What is Centrex virtual exchange service?

by John Tyreman, Mason Communications

Centrex, or CENTRalised EXchange, is a service offered by some telecoms operators that allocates a section of a public telephone switch to dedicated use by a single organisation. It gives you the functionality of a private telephone switch without the need for in-house telecoms equipment or expertise, and is especially useful for small companies.

How does it work?

An organisation using Centrex is allocated the number of extensions it needs in a closed user group. The service can be used within a single building or across multiple sites, in which case a virtual private network (VPN) is installed. No special equipment is required on the customer's premises - the process is as simple as fitting a normal telephone line.

What functionality is available?

As a minimum the following features are usually available on each extension:

What does it cost?

Costs vary between providers, however installation is likely to be about GBP40 per extension, with line rental between GBP11 and GBP15 per month. Calls between extensions within your user group are free of charge, including those to extensions on a different site, as is use of any of the features. Calls to numbers on the public network are charged at the normal rate.

Cost benefit analysis

Before signing up to use Centrex you should conduct a cost benefit analysis, comparing costs with those for a small telephone system over a period of at least three years and taking into account any anticipated increases in telephony requirements.

The following should be taken into consideration for each option:

What are the advantages?

What are the disadvantages?

Reviewed January 2011

last updated : 21/01/2011



See also our UK ICT Directory for supplier lists and links



search TelecomsAdvice

browse the index

A B C D E F G H I
J K L M N O P Q R
S T U V W X Y Z  

browse categories

UK ICT Directory

telecomsadvice blog

advertising sponsorship

help

site map

contact us