How ENUM works

ENUM (telephone number mapping) is a suite of protocols that defines a rule making it possible to relate a domain name to a telephone number, and then use that domain name to identify various communications devices such as fax, mobile phone, voicemail, email, IP telephony addresses or web pages.

Connection using DNS

ENUM uses the Domain Name System (DNS) to create a connection between the addresses of computers connected to the Internet and domain names, which are much easier for people to memorise.  The majority of Internet users are probably only familiar with domain names in combination with web sites or email addresses.  However, in future the ENUM protocol working with the DNS infrastruture will make it possible to obtain information about telecommunication services and access them via domains.

ENUM translates a telephone number into a domain name

For example: 01865 332211 becomes 1.1.2.2.3.3.5.6.8.1.4.4.e164.arpa where '44' is the UK's international dialling code. 'e164' is the name of the telephone numbering system and '.arpa' is the Internet infrastructure equivalent of .uk or .com.

A computer can understand and connect to this address in a fraction of a second which makes ENUM a quick, stable and cheap link between the telecommunications system and the Internet.