Call Forwarding with ENUM

This interactive voice response (IVR) diagram sample illustrates how ENUM call forwarding can be achieved. It was designed on the base of the Wikimedia Commons file: Call Forwarding with ENUM.jpg. [commons.wikimedia.org/ wiki/ File:Call_ Forwarding_ with_ ENUM.jpg]
"Telephone number mapping is a system of unifying the international telephone number system of the public switched telephone network with the Internet addressing and identification name spaces. Internationally, telephone numbers are systematically organized by the E.164 standard, while the Internet uses the Domain Name System (DNS) for linking domain names to IP addresses and other resource information. Telephone number mapping systems provide facilities to determine applicable Internet communications servers responsible for servicing a given telephone number using DNS queries.
The most prominent facility for telephone number mapping is the E.164 Number Mapping (ENUM) standard. It uses special DNS record types to translate a telephone number into a Uniform Resource Identifier (URI) or IP address that can be used in Internet communications." [Telephone number mapping. Wikipedia]
The IVR diagram example "Call Forwarding with ENUM" was designed using ConceptDraw PRO diagramming and vector drawing software extended with the Interactive Voice Response Diagrams solution from the Computer and Networks area of ConceptDraw Solution Park.

This IVR diagram sample 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.
This IVR diagram sample was designed on the base of the Wikimedia Commons file: Ejemplo ENUM.jpg. [commons.wikimedia.org/ wiki/ File:Ejemplo_ ENUM.jpg]
"Being able to dial telephone numbers the way customers have come to expect is considered crucial for the convergence of classic telephone service (PSTN) and Internet telephony (Voice over IP, VoIP), and for the development of new IP multimedia services. The problem of a single universal personal identifier for multiple communication services can be solved with different approaches. One simple approach is the Electronic Number Mapping System (ENUM), developed by the IETF, using existing E.164 telephone numbers, protocols and infrastructure to indirectly access different services available under a single personal identifier. ENUM also permits connecting the IP world to the telephone system in a seamless manner." [Telephone number mapping. Wikipedia]
The IVR diagram example "Example ENUM" was designed using ConceptDraw PRO diagramming and vector drawing software extended with the Interactive Voice Response Diagrams solution from the Computer and Networks area of ConceptDraw Solution Park.

"An example scenario is presented to demonstrate how a common issue tracking system would work:
(1) A customer service technician receives a telephone call, email, or other communication from a customer about a problem. Some applications provide built-in messaging system and automatic error reporting from exception handling blocks.
(2) The technician verifies that the problem is real, and not just perceived. The technician will also ensure that enough information about the problem is obtained from the customer. This information generally includes the environment of the customer, when and how the issue occurs, and all other relevant circumstances.
(3) The technician creates the issue in the system, entering all relevant data, as provided by the customer.
(4) As work is done on that issue, the system is updated with new data by the technician. Any attempt at fixing the problem should be noted in the issue system. Ticket status most likely will be changed from open to pending.
(5) After the issue has been fully addressed, it is marked as resolved in the issue tracking system.
If the problem is not fully resolved, the ticket will be reopened once the technician receives new information from the customer. A Run Book Automation process that implements best practices for these workflows and increases IT personnel effectiveness is becoming very common." [Issue tracking system. Wikipedia]
The UML sequence diagram example "Ticket processing system" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Rapid UML solution from the Software Development area of ConceptDraw Solution Park.