ENUM, the acronym for Electronic Number or Electronic Numbering, is an electronic directory service function that unites a telephone number with any electronic communication applications associated with it. It does this by using a protocol developed by an Internet Engineering Task Force (IETF) working group of the same name and uses an architecture based on the Domain Name System (DNS). It is based on the numbering that is used when making telephone calls - E.164 numbering.
With ENUM and using E.164 numbering, the goal is for it to be possible for users of different electronic communication service types and means (e.g. voice, email, fax. message services, etc.) to communicate with each other even though they only have the other user's telephone number as a reference for access and identification. In this way Internet applications can also be made available to users of traditional networks and visa-versa. Accordingly ENUM is seen as an important element in the convergence between electronic communication networks and services.
Through the use of DNS, ENUM identifies the available ways of contacting a specific subscriber, identified by a telephone number. With their telephone number registered on DNS, the owner can, by configuring this registry, associate a range of data with this number, such as their fixed telephone number, an email address, a fax number, a mobile telephone number, a message service, voice mail. The information contained in the registry will indicate the types of application and communication services employed by the user. The user can also assign an order of preference for contacts.
ENUM protocol is designed so that services associated with an E.164 number can be consulted by converting this number into its international format, including the country code and internet domain name. This conversion is done by separating the digits with full stops, switching the direction in which it is read and adding the top-level domain. The top-level domain to be used is ''e164.arpa'', although no consensus has yet been reached on this or any other top-level domain.
Should ICP-ANACOM opt to include its telephone number in the DNS for purposes of ENUM, the search can be done based on the name 0.0.0.1.1.2.7.1.2.1.5.3.e164.arpa, normally obtained by a conversion done by the client application or VoIP server. The result of a search will give, for example, the fax number, email and web site address or anything else associated with ICP-ANACOM's general number.
ICP-ANACOM, as part of the public consultation process for the introduction of new technologies and services, has already deliberated on regulatory measures for VoIP services which ENUM facilitates, and aims to evaluate the market interest for ENUM, so that an action plan for its introduction in Portugal can be formulated.
The objective of the consultation is, therefore, to collect opinion about the importance of ENUM to operators, service providers and users in general, as well as about the services and applications that could potentially or additionally be offered through ENUM, a model for administration and the most appropriate and efficient technical solutions. Opinions are also being sought on the interest of providers in setting up a pilot scheme that could be used to make tests.
Consult:
- ENUM service https://www.anacom.pt/render.jsp?contentId=1070315
