VoIP phones are without a doubt future of the modern communication. They came to the world stage in the last decade of the 20th century and have ever since made a name for it. It has taken the entire communication experience one step further and developed it towards perfection. Analyzing the previous technologies and their shortcoming VoIP phones have come up with a communication technology that is reliable, cheap and has good voice quality. It serves its users with everything they want in a telephone.

But VoIP phones are not exactly telephones; though they do look like one but they do differ. Voice over internet protocol communication or commonly known as (VoIP) uses the internet for communication amongst peers; this form of communication has virtually replaced the traditional medium of telephones. Rather than coming up with a new technology it has utilized the already existing model and developed it according to its specifications. Previously in analog telephones sound used to travel on telephone lines between sender and receiver. A simple device is used for modulating voice signals into electromagnetic so that it could transfer to the physical medium and the receiver converted back into sound.

With the development of technology and introduction of computers, analogue signals were shifted into digital format. In this format sound signals are transferred into electric current. This method has formed the basis of internet communication because it can be used by any device which has the computer in it. But for the development of VoIP phones the preexisting technology needed to be modified. The modem which is part of every computer in the market needed to be converted into a handheld device compatible. The entire digital communication is based upon harry Nyquist’s algorithm for sampling and that led to the device called “codec”. A codec is responsible for internet communication amongst VoIP phones.Following are few codec’s that have been developed

Following are few codec’s that have been developed over time and how this software enables communication amongst VoIP phones.G.711

G.711
Is a codec which ensures accurate communication with the utilization of minimum resources? It is also known as pulse code modulation because it works over high bit rate than other codecs. A PCM is most useful for Fax machine and its transmitting of data over the VoIP systems.G.722

G.722
This codec is best suitable for network-based communication because it provides the user with the compatibility with variable speeds. Due to its compatibility, it provides unmatched voice quality and is highly reliable. G.722 is normally used over local area network because of variable rates of communication available.

G.723.1
This codec is best utilized for dial-up communication. It uses low bandwidth for communication and provides excellent voice quality making it suitable for utilization in household computers.

G.726
This codec hails from the family of the codec discussed previously. It is used in wireless phones and for international calling.GSM

GSM
It works on the same principle as in the cell phones. It uses the same principle as the GSM technology.Speex

Speex
This codec is designed for audio communication. Its primary function is to ensure reliable sound transmission.