It means sending our using internet protocol. Means sending voice data over IP telephony. It sends information in the digital form rather than circuit packet data. It is better because it avoid charges which are charged in the telephone services. This VIOP is first used in the 1995 by an IT company Vocal Tec. They are better because the facility of the internet to transfer the information from one computer to another computer. To make a VIOP connection we require software, hardware and protocol.

 Software: used may vary from one organization to another, it depends upon their requirements. We require voice processing module for transferring the voice sample and PCM interface to receive the sample and then forward to IP software for processing.

Hardware:we require the perfect hardware that can meet our requirement or organizational need which vary accordingly. We will require two gateways for transmission process, one for differentiating the IP network over telephony and other in case of failure of first.

Protocol:Protocols are required for maintaining the audio signal of the voice. It defines the bandwidth of data. This protocol may be real time protocol or resource reservation protocol.

Advantages and disadvantages: we only require one cable for both data and voice connection. It reduces the cost of installations. It reduces the waste of bandwidth by eliminating the silence speech. They are based on the software so they can upgrade and maintained. It is not best for real time use. If the network is busy due to traffic then communication might be de-graded.

Now the most vendors use VPN to ease the IP telephony network. They set transmission by encrypting the data by the technique cryptography. This also provides security to their data.

Download  Voice over IP PPT .