Ntc 360 - Voice over Internet Protocol

NTC/360 - Voice over Internet Protocol (VoIP)

06/15/2005

Voice over Internet Protocol (VoIP)

Definition of VoIP

"Mr. Watson, come here, I want you!" These were the first words that were spoken over the phone back on March 10 1876. If you combine this invention with the same invention of the first computer that was completed nearly 70 years later in 1946, you would then be able to access VoIP. VoIP is also known as voice over internet protocol. VoIP is in essence the ability to talk with ones voice via computer to computer. In the next few pages you will learn about the history of VoIP, how it works, the requirements that are needed to use VoIP, the benefits and risks of this type of technology, and lastly you will get a glimpse at the future of VoIP.

Not many people know what VoIP is or even that it exists. VoIP was designed to help with the costs for long distance charges. The idea or premise of this type of technology was conceived to use ones phone line and make a call through the Internet. It was designed to be used for both local and long distance calls thus cutting phone bill costs.

The VoIP way of communication was started back in 1995 and was the result of work done by some hobbyists in Israel (Interangent, 2005). These hobbyists as well as other great inventors saw a good idea. Their idea was to be able to communicate through the computer as appose to talking over the phone. The idea was not so much to get away from the phone system but more to avoid long distance charges. In the beginning VoIP was only available when there was a direct personal computer to personal computer connection. Later in 1995 Vocaltec, Inc. released Internet Phone Software (Interagent, 2005). In the beginning it was fairly difficult to use. Due to the fact that in order to really be able to communicate using VoIP both the computers that were trying to communicate to each other would be required to use the same equipment, have a sound card and use a microphone. It was a good first effort, but as many firsts, the quality was very poor.

VoIP would make great strides in the next three years. In 1998 VoIP had made such great strides that some companies were able to offer personal computer to phone services. The strides also were able to offer phone to phone contact. In the beginning VoIP did not charge their customers but chose to get payment through advertisements. When you made the phone call you would have to wait through an advertisement.

In the beginning, VoIP was still dependent

on phone lines through internal or external modems and that kept the quality poor because of static and dropped connections. With the introduction of Ethernet services the quality was able to get better. There was better clarity but there were still some bugs due to static and difficulty making connections.

In the beginning VoIP traffic represented rather less than 1% of voice traffic. In 1998 three IP switch manufacturers introduced equipment capable of switching (intertangent, 2005). With these implementations by the year 2000 the voice traffic had risen only two more percent to 3%. This is not a huge leap but there are many advances that are still being made and the numbers will continue to grow.

The real breakthrough occurred when such systems like Cisco Systems and Nortel started producing VoIP equipment that was capable of switching (Viopreview, 2005). With the introduction of switching it was no longer the CPU's responsibility to switch the voice packets. With the introduction of the new switching this made it to where the computer did not require specific hardware to be able to use VoIP. When the switches were introduced this made the hardware cheaper and allowed larger companies to be able to implement their calls via the internet.

VoIP has not really caught on with the general public, but has been primarily used by large corporations. The general public does not really search out things such as this because they sometimes become complacent in their day to day life. On the other hand, large companies will search out any way to reduce costs. Large companies can reduce costs of business communications, which may include fax, conference calling, along with streaming video application (Try, 2004). Large companies such as call centers were able to implement VoIP to also cut costs.

VoIP may not have been something in the past that was readily used by the public. The public has found other ways to cut their long distance phone calls and with the packages that the phone companies have offered it may not be feasible or even become widely used. The main people entity that sees the value in VoIP is the large corporations and they have in recent years seen the benefits. VoIP is being used and has been noticed and will continue to be sought after by larger corporations whom wish to continue to cut their costs.

How VoIP Works

VoIP Packet Switching

To fully grasp the concept of how Voice over Internet Protocol (VoIP) works, it is necessary to have a full comprehension of the differences between circuit switching and packet switching. The current method of routing phone calls on a public switched telephone network (PSTN) involves circuit switching. Phone calls are routed or switched at the local telephone exchange site's switching centers and directed to the location being called. This connection of the calling and called stations in both directions creates a continuous electrical circuit which is established until one the calling stations releases the transmission. VoIP, on the other hand, utilizes packet switching to manage data transmissions.

Packet switching works by taking packets (messages or fragments of messages), and individually routing them between nodes (network devices) which have no previously established communication path. Packet switching uses optimal bandwidth and minimizes latency during data transmissions. Since VoIP utilizes packet switching, it has become a more efficient way of transmitting data and it possesses several advantages over circuit switched PSTN phone networks. The main difference between packet switching and circuit switching is that packet switching allows numerous phone calls to fill in the area occupied by only one phone call in a circuit switched network. For example, a 15 minute phone call using PSTN would use the full 15 minutes of transmission time at about 128 kbps. However, this same call using VoIP may only take 3 to 4 minutes of transmission time at about 64 kbps. The