Definition - What does Telephone Number Mapping (ENUM) mean?
Telephone number mapping refers to the mapping of telephone numbers with Internet identification and addressing name spaces. E.164 NUmber Mapping (ENUM) is an Internet Engineering Task Force (IETF) standard for mapping public switched telephone networks (PSTN) in the DNS. ENUM is the protocol through which a telephone number is mapped as an IP address, therefore making the Internet accessible through a telephone number.
Techopedia explains Telephone Number Mapping (ENUM)
Telephone number mapping is a solution for providing Internet subscribers with a cheap, easy connection to the Internet. Users must register phone numbers for ENUM much like registering for a domain.
ENUM allows operators to define specific routes for several types of calls. Users with ENUM-registered numbers can have calls forwarded in different modes. This enables users to increase their communication options even when the phone line is busy.
There are three main types of ENUM:
User ENUM:Normally known as public ENUM, it is the original aspect of ENUM where users have the option to select a country code level from the E164.arpa domain.
Private ENUM: ISP and VoIP service providers can use ENUM for internal use.
Carrier ENUM: Service providers mutually decide to share user information through ENUM.