If you have an ear open to new computer
technologies, you are sure to have heard about VoIP. Voice over Internet
Protocol (VoIP) is an emerging set of applications which allows you to
make telephone calls over the Internet. It is already starting to
replace existing telephone networks, with some people and businesses
opting to cancel their traditional phone line and use VoIP instead.
VoIP was originally developed to provide voice communication between
computer users in different locations. Although it still has this
application, it has been further developed into a telephone network in
its own right. People using VoIP can call any telephone anywhere in the
world and can receive calls on telephone sets connected to the Internet
or Local Area Network (LAN).
Background
It all started back in 1995 when Israeli computer enthusiasts made
the first computer to computer voice connection. In the same year this
technology was developed into a software package called Internet Phone
Software. All that was needed to talk to another computer user was a
modem, sound card, speakers, and a microphone.
The software digitized and compressed the audio signal before
sending it over the Internet in data packets. These voice connections
could only occur between computers which had the software installed. The
sound quality was very poor -- nowhere near the quality of standard
telephone connections.
The technology continued to be developed and by 1998 gateways had
been established to allow PC-to-phone connections. Later that same year
phone-to-phone connections that used the Internet for voice transmission
were set in place. These phone-to-phone connections still required a
computer to initiate the call, but once the connection was established,
the callers could use a regular phone set.
VoIP Today
There are currently many VoIP services available for residential and
commercial use. Some of these still rely on PC-to-PC connections but
may offer other services such as PC-to-phone and phone-to-phone.
Internet phones are available that plug into the sound card or USB
port of a computer. These phones may have number pads and ringers that
allow you to use them the same as traditional telephones. The computer
can be bypassed completely by connecting a phone directly to a broadband
modem (either DSL or cable).
How Does It Work?
The first step in using VoIP is converting your voice into digital
data. This is done by 'sampling' your voice -- dividing the analog sound
signal into discrete steps that can be assigned a number value. Once
your voice is digitized, the data can be compressed.
This compressed digital data is split up into 'packets' of about
1500 bytes that can be transferred over the Internet. As well as the
voice data, the packets contain information about their origin, their
destination, and a timestamp that allows them to be reconstructed in the
correct order. Once they arrive at their destination, they are
reassembled and converted from digital back into analog so that the
receiving party can hear your voice.
In order for voice data to be transmitted without noticeable delays,
a broadband Internet connection is necessary. Many households and
businesses are already using broadband (either DSL or cable) so adding
VoIP is relatively simple.
About the author:
Mark is a technology consultant in the great Orlando area. His blog can be read online at http://www.voipblogonline.com
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment