For long, voice and data transmission needs have been treated separately,
with the voice part coming under the administration department. But that can no
longer be the case, what with data and voice transport converging at a furious
pace, and even the law of the land giving it the nod.
|
|
|
Existing establishments will have a separate network to carry voice traffic
and a different one to carry data traffic. This necessitates the need for two
networks and associated costs of setup, maintenance and management. With
developments in network design and the emergence of convergence technologies,
data and voice traffic can now be integrated into the same internal network,
without loosing voice quality. Apart from reduction in overall equipment and
maintenance costs, additional benefits include easier and centralized
management, better uptimes, more feature-rich telephony, and prospects of
integrated video-conferencing too.
With integrated voice and data systems, your PCs and your telephones will
connect to the same network. In fact, your PC may well connect to the telephone,
which in turn is connected to the LAN. Your connect to the external world would
currently split into two, with the voice part connecting to the PSTN and the
data part connecting to the Internet or to WAN links. In the future, as these
two merge, this separation would no longer exist.
The technology that makes this possible is VoIP (Voice over Internet
Protocol). Voice can be digitized (by sampling), compressed and encoded into
packets that can go over traditional data networks. The process is reversed on
the receiving end to get back the original voice.
Infrastructure requirements would be almost the same as in the case of a data
network–same hubs, network ports and switches. But your routers have to be
voice-enabled to transport the voice data and have the capability to handle
Quality of Service (Voice quality has to be maintained, so part of the band
width has to be dedicated to voice, or voice has to be given more preference
over data) and other service criteria. Also, your EPABX will now not be a
console, but a full-fledged server with associated networking equipment.
For the end-users, you will need IP-phones that connect to your LAN in the
same way as any other PC or network device would connect. These phones will be
identified with MAC addresses and IP addresses like any other network device.
IP-phones as we saw, would have a MAC address and are assigned IP addresses
by the controller software on a server. When an IP-phone instrument is connected
to a network, it is identified by its MAC address. A record of phone numbers,
rights and other settings is also kept on the server. The phone identifies
itself and retrieves all this data from the server and starts functioning. The
software also gives features like directory lookups, answering machine and a
host of other benefits.
It is not necessary that you have IP Phones only. Normal phones will work,
through special connectors. But they would not give you the additional features
that IP phones have, like directory search and auto configuration for example.
Ashish Sharma