Introduction to Internet Telephony and VoIP
Internet telephony is a combination of
software that enables people
to use the Internet
as the transmission medium for telephone calls. For users who have free,
or fixed-price Internet access, an Internet telephony software package provides
free telephone calls anywhere in the world. Some Internet telephony software like
bundled with popular Web
browsers. Others are
products. Internet telephony products are sometimes called IP telephony,
Voice over the Internet (VOI) or Voice over IP (VoIP) products.
VoIP hardware and software work together to use
the Internet to transmit telephone calls by sending voice data in packets using
IP rather than by
traditional circuit transmissions, called
Switched Telephone Network). The voice traffic is converted into
packets then routed over the Internet, or any
network as normal data packets
would be transmitted. When the data packets reach their destination, they are converted back to
voice data again for the recipient.
In its simplest form,
PC to PC Internet telephony
can be as easy as hooking up a microphone to your
computer and sending your voice through a
cable modem to a person anywhere in
the world. This works so long as you are communicating with someone who has an
Internet connection and Internet telephony software that is compatible with
yours. This type of communication requires
only a small one-time purchases outside of your normal Internet connection bill from
your ISP. For PC to PC telephony you need a microphone for talking into and a
sound card and speakers so
you can hear the person on the other end of the call. You will also need to
purchase (or download and install
shareware versions) of an Internet telephony
software package such as NetMeeting, CU-SeeMe, or MediaRing Talk to name just a few.
This basic form of Internet telephony is not
without its problems, however. Connecting in this way is slower than using a
traditional telephone for communication, and the quality of the voice
transmissions is also not near the quality one would get when placing a regular
phone call. The benefit is that you can talk up a storm with family
and friends without incurring long distance charges on your telephone bill! This
can be an ideal solution for home users.
Hardware-based VoIP Solutions
VoIP solutions for small
business and large corporations are not free, but do offer a substantial
savings over using traditional telephone carriers. In
recent years, we have seen many changes in this area of technology. With a
phone adapter that connects your telephone to your high-speed
you can pick up the phone as you normally would and place a telephone call.
Despite the fact that you are communicating via the Internet with a telephone,
the technology still works in the same way it does with PC to PC calling.
VoIP changes the voice data from your telephone into a
digital signal that travels over the Internet then converts it back at the other
end, but in this case you can communicate with anyone who has a regular phone
The flow of VoIP in a
hardware-based solution is your telephone is connected to a VoIP phone adapter (considered the
hardware aspect). This adapter is connected to your broadband Internet
connection. The call is routed through the Internet to a regular phone jack, which is connected to
the receiver's phone. Special hardware (the phone adapter) is required only
for the sender it is not required on the receiving end.
Much like finding an
Internet service provider (ISP)
for your Internet connection, you will need to use a VoIP provider. Some service
providers may offer plans that include free calls to other subscribers on their
network and charge flat rates for other VoIP calls based on a fixed number of calling minutes. You
most likely will pay additional fees when you call long distance using VoIP.
While this sounds a lot like regular telephone service, in the long run it is
found to be a much cheaper way to voice communicate overall, starting with the
fact that you will no longer need to pay for extras on your monthly phone bill.
This is especially apparent in a business setting where you can avoid paying for
multiple business telephone lines and services as you can essentially pay for
one line in (this line is needed for your
connection if you're using
DSL or a T1),
and the VoIP provides the service for the actual calls, voice messaging, and the
additional features you may require for your business. Your choice of plan with
a VoIP provider is going to determine your overall fees for using a VoIP service
as opposed to using a PSTN.
VoIP Meets WiFi
The advances of VoIP and Internet
telephony in general have come a long way since their inception. Most recently, the
"next big thing" has been to merge Wi-Fi with VoIP, producing one of the oddest
acronyms you'll ever see.
VoWiFi. VoWiFi, or Voice
over Wireless Fidelity, simply means a
VoIP service or in even
more general terms, a wireless based VoIP system.
Where VoIP consists of the
enables people to use the
Internet as the
transmission medium for telephone calls, VoWiFi is the wireless version of this
technology that is designed to work on wireless devices such as a
Some may wonder why a person
or organization wouldn't simply use a
cell phone for
mobile communications, but
again business and organizations can take advantage of a decreased
communications cost while having a mobile system that offers more reliable
coverage indoors and higher voice quality than traditional cellular service with
Along with added benefits
to business and those with a need for wireless communications, VoWiFi also opens
up the door for a whole new market of consumer products such as a standalone
VoWiFi handheld. Many cellular phone companies such as
Nokia and Motorola have already announced dual-mode
cellular phones that will support seamless
roaming from WiFi to
cellular networks when WiFi is unavailable to a caller. That is one of the biggest
VoWiFi roaming access. A WiFi access point offers a communication range of up
to 90 meters (commonly called a hotspot), and continuous conversations would
mean that the caller must stay within an area of overlapping hotspots, or as
already suggested, have a VoWiFi
dual-mode phone that would switch to a regular cellular phone transmission when
the caller moves out of a hot spot range.
Communicating using VoIP over Wi-Fi is something
many people are paying close attention to. Cellular companies aren't feeling too
threatened yet due to
some of the more serious problems facing VoWiFi; like roaming access and security.
These issues may take years to
iron out, if they ever are. It can be said that not many people really expected to see the
cellular phone industry take off like it did, and only time will tell if VoWiFi
is truly the next big thing in wireless communications or if it's just the next
great idea that consumers didn't quite get.
Vangie 'Aurora' Beal
Last updated: February 7, 2005
Wi-Fi Planet (formerly 802.11 Planet) is your complete guide to
the world of networking products based on the various 802.11 wireless networking
protocols (collectively known as Wi-Fi). With daily news, features, reviews, and
tutorials, Wi-Fi Planet covers all areas of the rapidly changing wireless
To find HotSpots near a location, enter a
complete or partial address. By default, all locations within 1 mile are shown.
Click on "Browse by Region" to see all HotSpots in a city. Click on a HotSpot
name for a map within the U.S. and Europe.
Computer Telephony Portal
A comprehensive directory with more than 600
links to industry sites and CTI information sources as well as Voice over Frame
Relay, Voice over Internet and telephony standards pages.
BTI Communications -
All about Voice Over IP and Internet Based