What does ENUM mean?
ENUM is a term that springs up now and again, but what is it referring to and why is it something to pay attention to? ENUM stands for telephone number mapping. It is a simple four letter acronym representing a monumental idea: being able to use the same phone number no matter where in the world you are.
If you visited this page looking for enum (enumerated data type) instead of the ENUM protocol, please refer to this page.
How does ENUM work?
ENUM unifies the international public switched telephone network (PSTN) with internet addressing. This works by translating standard telephone numbers into internet addresses (URL or IP address). Servers that support ENUM will search any dialed number in the ENUM tree of the DNS to locate substitute ways to setup a call outside of the standard PSTN telephone line.
What are the types of ENUM?
There are three different types of ENUM:
Rules for ENUM numbers
The owner of each ENUM number has the ability to publish their number and choose rules for how the call should be routed. This could be one rule for a call from a fax machine and another from a phone. ENUM requires the specific support from the phone of the caller.
How do you register an ENUM number?
An ENUM number is registered much like how you would register a domain. At present many registrars and VoIP providers are providing this as a free service. Registration needs to be done through a registration service such as Ripe with the standardized ENUM request form. This is then registered with the International Telecommunication Union, Telecommunication Standardization Sector, Telecommunication Standardization Bureau (ITU-T TSB). After this the number is registered and ready for international use.
New but growing standard
ENUM is a new standard and is not that widespread yet. Though it looks to become another revolution in communications and personal mobility. As more and more providers utilize it the mobility of workers and individuals alike will be greatly increased and costs will continue to decrease.