VoIP as a New Trend
There is a new trend that has taken the networking technology to the next level. It all started in the 90’s looking for a less expensive way to make phone calls across the world. Both residential and commercial customers have been looking for a cheaper way to make local and international calls. This new revolution is called Voice over Internet Protocol (VoIP). If I had to put this in plain terms, this technology allows voice traffic to be transmitted over the Internet.
VoIP is a new application of Internet Protocols (IP) that enables the conversion of voice communications into data packets and then these ...view middle of the document...
Instead packet switching is used, where IP packets with voice data are sent over the network only when data needs to be sent when a caller is talking”. (Newave.net 2007)
The term Internet Telephony has been generally applied to a family of applications that includes voice communication over a network using Internet Protocol. McKnight, Lehr, and Clark (2001) define Internet telephony as "the services, applications, and equipment for mediated human communication emerging from the convergence of the Internet and telecommunications."
Let’s go back to for a moment and give a small explanation of how the plain old telephone system worked. Plain old telephone service (POTS) is the voice-grade telephone service that remains the basic form of residential and small business service connection to the telephone network in most parts of the world. POTS has been available almost since the introduction of the public telephone system in the late 19th century, in a form mostly unchanged to the normal user despite the introduction of Touch-Tone dialing, electronic telephone exchanges and fiber-optic communication into the public switched telephone network (PSTN). “Analog is the transmission of electronic information by adding signals of varying frequency or amplitude to a carrier wave of a given frequency” Riley (2003). In the Traditional telephone communications calls where converted from analog to digital format using a 64Kbps bandwidth and back to analog by the PSTN.
On the other hand, VoIP converts voice into data packets and sends the voice packets over the internet. The packets get mixed with other voice and data packets and are then reassembled into voice by a telephone device at the distant end. The result is a telephone call over the Internet. To control routing calls to and from endpoints there is an IP PBX. The IP PBX is the server that all of the endpoints are logged in to. When an IP telephone require connection to a phone number on the PSTN a gateway is required. A user make a call to a specific number, the IP PBX routed the call to a gateway device where the number gets dialed into the PSTN like a normal phone call. (www.all-voip-guide.com 2008)
The way VoIP works is pretty simple, once you have selected your VoIP service provider, you will receive the digital phone box. This device will convert your analog voice into digital IP packets. These packets will then be routed to your cable modem or broadband router. From your LAN they will travel into the WAN or the Internet to its destination. Remember that the IP PBX is the one in charge of the route to take, no matter if the call is going to a PSTN or a Wireless Cell Phone carrier.
There are two major protocols used by VoIP technology to allow telephones, computers and other devices on the data network to communicate with each other: H.323 and SIP. The H.323 standard, a suite of protocols created by the International Telecommunications Union is a very wide-ranging and very complicated...