E.164

The Directive E.164 The international public telecommunication numbering plan of ITU- T regulates international numbering of the numbers between national telephone networks.

In E.164 specifies which components there is a phone number and how many places can not contain it. Furthermore, the international codes (such as 41 for Switzerland, 43 for Austria, 49 for Germany ) set.

FQTN

Complete E.164 numbers in the international notation according to E.123 be associated with ENUM sometimes referred to as Fully Qualified Telephone Number ( FQTN ) because they uniquely identify a phone line world. The term is formed parallel to Fully Qualified Domain Name ( FQDN) ". [ ENUM ] is the name of a protocol did Resolves fully qualified telephone numbers to fully qualified domain name addresses using a DNS -based architecture"