The Figure illustrates how ENUM works by giving an example: Subscriber A sets out to call Subscriber B:

1. The User Agent of an ENUM-enabled subscriber terminal device, or a PBX, or a Gateway, translates the request for the number +34 98 765 4321 in accordance with the rule described in RFC 3761 into the ENUM domain 1.2.3.4.5.6.7.8.9.4.3.e164.arpa.
2. A request is sent to the Domain Name System (DNS) asking it to look up the ENUM domain 1.2.3.4.5.6.7.8.9.4.3.e164.arpa.
3. The query returns a result in the form of so called Naming Authority Pointer Resource NAPTR records, as per RFC 3403. In the example above, the response is an address that can be reached in the Internet using the VoIP protocol, SIP per RFC 3261.
4. The terminal application now sets up a communication link, and the call is routed via the Internet.

Designed by myself, User:Abasota, using Visio

This diagram image could be re-created using vector graphics as an SVG file. This has several advantages; see Commons:Media for cleanup for more information. If an SVG form of this image is available, please upload it and afterwards replace this template with {{vector version available|new image name}}. It is recommended to name the SVG file “Ejemplo ENUM.svg”—then the template Vector version available (or Vva) does not need the new image name parameter.

This diagram image was uploaded in the JPEG format even though it consists of non-photographic data. This information could be stored more efficiently or accurately in the PNG or SVG format. If possible, please upload a PNG or SVG version of this image without compression artifacts, derived from a non-JPEG source (or with existing artifacts removed). After doing so, please tag the JPEG version with {{Superseded|NewImage.ext}} and remove this tag. This tag should not be applied to photographs or scans. If this image is a diagram or other image suitable for vectorisation, please tag this image with {{Convert to SVG}} instead of {{BadJPEG}}. If not suitable for vectorisation, use {{Convert to PNG}}. For more information, see {{BadJPEG}}.

Moved from English Wikipedia, original upload history:
(del) (cur) 16:24, October 24, 2006 . . user:Abasota (Talk | contribs) . . 999×479 (35,376 bytes) (ENUM Application scenario Author: user:Abasota Drwn using Viso)
(del) (rev) 15:22, October 24, 2006 . . user:Abasota (Talk | contribs) . . 999×479 (43,115 bytes) (Drawn using Visio, by User:Abasota)
(del) (rev) 15:21, October 24, 2006 . . user:Abasota (Talk | contribs) . . 999×479 (43,029 bytes) (Drawn using Visio, by User:Abasota)
(del) (rev) 14:54, October 24, 2006 . . user:Abasota (Talk | contribs) . . 999×461 (44,131 bytes) (To illustrate how ENUM works. Designed by myself, User:Abasota, using Visio)

This work has been released into the public domain by its author, Abasota at English Wikipedia. This applies worldwide. In some countries this may not be legally possible; if so: Abasota grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.Public domainPublic domainfalsefalse