What is VOIP?

VOIP is an acronym for Voice Over Internet Protocol. The acronym accurately describes the purpose of the technology, yet hints at the difficulties in implementation to those familiar with IP (Internet Protocol). The term VOIP refers to no particular protocol or method, rather, the term applies to a number of technologies that aim to adapt the Internet's packet-based data exchange methods to real-time two-way communication.

Internet Protocol (IP) prioritizes the reliability of data transfer over the speed of data transfer. Thus, if 100 packets are sent in one second, IP makes sure that 100 packets are received, even if it takes 30 seconds to receive them. This type of system ensures that the file received exactly matches the file sent. However, this type of data transfer is not well suited to voice communication. Imagine what a telephone conversation would be like if one second of speech took 30 seconds to hear! The main challenge in creating a usable VOIP protocol is in ensuring that every one second of speech sent is played back on the receiving end in a one second time span, without waiting for all the packets to be received.

The most popular VOIP protocol in use today is the proprietary Skype protocol. Yahoo, Microsoft, AOL, and countless others have competing VOIP protocols incorporating a variety of creative solutions to the problem. Many of them have near-ISDN quality when used in high-bandwidth environments, yet none of them can cope in a dial-up (56 Kb/s) environment. Also, in some areas VOIP service is being rolled out as an alternative to traditional ISDN lines, with special equipment that ensures compatibility with legacy telephones.