General Information

General Information about ENUM

ENUM is a protocol for connecting resources from telecommunications and the Internet to one another. It defines a rule which makes it possible to relate (map) a domain to a telephone number without any risk of ambiguity. This domain can then be used to identify various communication services, such as fax, mobile telephony, voice-mail systems, e-mail addresses, IP telephony addresses, web pages, GPS coordinates, call diverts or unified messaging.

For this purpose, ENUM makes use of the Domain Name System (DNS) that has been established for several years. One of the functions of DNS is to create a logical connection between the addresses of computers connected to the Internet (which are identified by their IP addresses) and domains, which have the advantage that they are much easier for people to memorize. To date, the vast majority of Internet users are probably only familiar with domains in combination with e-mail addresses or websites. However, the DNS infrastructure and the ENUM protocol make it possible to call up and access telecommunication services via domains. By contrast to .de domains, however, users are not free to choose their ENUM domain, since there is a fixed rule as to how an ENUM domain must correspond to a telephone number. The respective ENUM domain for a particular telephone number can thus only be registered by the person holding that number.

ENUM - A Single Number for All Services

The most obvious advantage of ENUM is that all sorts of communication may be handled via a single identification code. Instead of having to deal with many different numbers and addresses, a single telephone number will suffice. Moreover, by linking telephone numbers with Internet resources and integrating presence functionality, completely new services may be realized. For instance, special solutions offer the called person the possibility of signalling to the caller which communication channel he/she currently prefers. Correct assignment to the applications is made through the entries on the ENUM name server.

We have compiled examples how ENUM may be used for services and products on a separate page.