The digital worlds are growing together more and more. Just like the music
industry that used to deal with nothing but their own media (i.e. records/CD),
and today has to face the competition of PCs and the Internet, the phone
industry will also fuse with the Internet.
Today it is no problem to call up a phone from a computer. There has to be a
possibility to go the opposite way and call a computer from a normal phone, of
course. There is the difficulty, however, that a PC cannot be addressed
by a phone number. This is where ENUM comes in to close the gap.
As well as the next problem of switching to another system. The systems for
the time being have to exist in both worlds. A ENUM domain is like a directory
to match normal phone numbers to internet ones. So ENUM provides the technical
background to combine those two. Because of that, most implemenataions of ENUM
are not found visible for the user, but work in the background of the existing
ENUM is the abbreviation for
»tElephone NUmber Mapping«.
It contains the link of internet domain names on the one hand and the system of phone numbers on the other hand.
The domain name-system is used as system of addresses.
To be more precise, a phone number is registered as the domain name. Instead of
a usual entry for a www-server, however, an entry is used that indicates under
address the voice service is currently available.
These entries can be composed in a rather complex manner. You could determine,
for instance, that till 6 pm all incoming calls are directed to the PC
in the office, while after 6 pm the calls can be taken from a mobile phone.
Futher entries could also be applied to fax numbers. It is likely to say that in case the fax is busy
the fax can be transmitted as e-mail to a particular e-mail address. As you can see,
there are many promising possibilities.
In the following, some scenarios of calls are demonstrated.
The classical phone call