What is VoIP (Voice over Internet Protocol)
How do we define VoIP? VoIP, as indicated by it's full description of Voice over Internet Protocol, is communication over an internet connection, preferably high-speed broadband.
To use VoIP in it's simplest form you need 2 computers, headset for each and VoIP software running on each computer. These computers need to be connected to the internet using a broadband connection but they could be anywhere in the world. The connection is made through VoIP software and in most cases both computers must be running the same software. This software is mainly free and can often be downloaded from the internet, Skype being a perfect example. Again, in general these computer to computer calls are free of charge.
Developments over recent years now allow computer to landline or mobiles to be made, this is again done through the special VoIP software. As the provider needs to pay for the connection to the external landline or mobile network, there is normally a charge for this type of call, but the charges are normally considerably less than using another landline or mobile phone. The phone receiving this type of call does not need any special software installed.
How is VoIP Transmitted
VoIP is transmitted digitally rather than using analogue protocols. The sound of the human voice is converted to a digital signal, compressed using a codec (encoder/decoder) which means that there is less data to transmit. There are various codecs and they vary in the sound quality, the bandwidth required, the computational requirements, etc. Each VoIP,software program, phone or gateway in general supports several different codecs, and when they talk to each other, they negotiate which codec they will use.
The compressed data is now sent over the internet using a transport layer called User Datagram Protocol (UDP). It is then re-converted back to analogue when it reaches the computer/phone at the other end.
Voice over IP Networks features some additional advantages including:
- you can talk to many people at once
- ability to send other types of data other than voice (such as files)
- innovations in data transfer and Internet speeds come about, it can only get better.
There are a variety of devices that can take VoIP calls. Some aren't even hardware at all, but software programs you can install on your computer (such as Skype ).
Traditional telephone networks are seeing the advantages in offering VoIP services as well, with such national companies as Verizon and AT&T jumping on the VoIP bandwagon. Vonage was one of the first widely known companies to offer VoIP services, and is priced competitively with newcomers to the market.
The VoIP market is predicted to expand rapidly, with predicted numbers rising into the millions in just a few years. The installation procedure for the gadgets required to take these calls is often simple, and can be done with little hassle. If you use a router or other device that can potentially mask or block your IP address, you may have to do a bit more adjusting to get it to work.
One of the main advantages of VoIP is the low cost. If you have a fast Internet connection (DSL or cable) you can make PC-to-PC phone calls anywhere in the world for free. If you wish to make a PC-to-phone connection, however, there's usually a charge for this but probably much cheaper than your regular phone service. You can also sign up with a VoIP service provider which charges a monthly fee in return for unlimited calls within a certain geographic area. For example, some VoIP services in the United States allow you to call anywhere in North America at no extra charge. Overseas calls are charged at a relatively small rate. Another advantage of VoIP is portability. You can make and receive phone calls wherever there is a broadband connection simply by signing in to your VoIP account. This makes VoIP as convenient as e-mail - if you are travelling, simply pack a headset or Internet phone and you can talk to your family or business associates for almost nothing. Phone-to-phone VoIP is also portable. When you sign up with a VoIP service provider the Internet phone or adaptor that is used with that service is assigned a unique number.
This 'phone number' remains valid even if your VoIP service is in London and you are connected to the Internet in Bangkok. An Internet phone is small and light enough to take with you anywhere. Simply plug it into a broadband connection anywhere in the world and you can make and receive calls just as though you were in your own home or office. There are many other features that make VoIP attractive. Call forwarding, call waiting, voicemail, caller ID and three-way calling are some of the many services included with Internet telephone at no extra charge. You can also send data such as pictures and documents at the same time you are talking on the phone