Kinds and Protocols of Voip

KINDS AND PROTOCOLS OF VOIP

A. Ways of Calling by VoIP:

There are three ways that you might talk to someone using VoIP. If you've got a computer or a telephone, you can use at least one of these methods without buying any new equipment:

* ATA : This is the most common way to make a VoIP call. You use a device called an analog telephone adapter. This adapter allows you to connect a standard phone to your computer or internet connection and place a VoIP call. This device is an analog to digital converter.

* IP Phones : Specialized phones look like normal phones, however instead of using a standard RJ-11 connector, it uses the RJ-45 Ethernet connector. These types of phones connect directly to your router and have all the hardware and software included.

* Computer - to - Computer : This is the easiest way to use VoIP. With the use of free software, a sound card, a microphone and speakers you can turn your computer into telephone. The only charge that you have to pay for this service is the cost that you pay each month to your Internet Service Provider(S2).

B. Protocols:

There are two major protocols being used for VoIP. Both protocols define ways for devices to connect to each other using VoIP. Also, they include specifications for audio codecs. A codec, which stands for coder-decoder, converts an audio signal into a compressed digital form for transmission and back into an uncompressed audio signal for replay. The first protocol is H.323, a standard created by the International Telecommunications Union (ITU). The second protocol is Session Initiation Protocol (SIP) under the auspices of the Internet Engineering Task Force (IETF). SIP is a much more streamlined protocol, developed specifically for IP telephony and it is smaller and more efficient than H.323(S2).