Understanding VoIP Protocols

Nearly any device ever designed to transmit video and audio packets between computers that communicate with one another, uses Real-Time Protocol (RTP). After the can serve as became evident that people communicating online has the potential for ease dropping on their communication, RTP (Real-Time Protocol) was enhanced to us more secure level. The secure RTP was developed for authentication, encryption and integrity of the video and audio packets that were transmitted online to communicating devices.

Part of the process of transmitting video and audio media between computers is the employment of various protocols. One such protocol locates the remote device to negotiate exactly how the media will transfer flow between each device. These types of protocols are known as call-signaling protocols, with the most popular being SIP (Session Initiation Protocol) and H.323. Each protocol relies on static provisioning and other protocols as a way to locate a variety of users.

First originated 1995, both SIP and H.323 were developed to solve the initial communication between two computers as a way to effectively exchange video and audio media streams. H323 experienced commercial success while SIP progressed at a slower level before being recognized as a standard in 1999.

Both protocols have the ability to perform the same action: to establish a multimedia level of communication including video, audio and other communications. However, there are designed significantly different with SIP being ASCII-based and H.323 being built on the foundation of binary protocol and legacy communication systems.

Although the jury is still out on whether SIP or H.323 can be held as the true standard for media transfer functionality, no one disputes the fact that both perform well. However, H.323 appears to be superior in a variety of ways including offering better support for videos, optimal interoperability with PSTN, premium interoperability of legacy video systems a more dependable out of band transport of DTMF.

Alternatively, SIP (Session Initiation Protocol) was never designed to work as a solution for the problems handled by H.323. Additionally, it gained its popularity by misinformation of being “easy to debug and implement”. Built as a complex communication system, they both perform identical amounts of work using to different approaches.

Of the two, SIP implementation is far easier to troubleshoot or develop. Likewise, H.323 is still the protocol to use in bulk VoIP deployments, especially when transmitting voice calls globally. Additionally, H.323 is the protocol most used for room-based videoconferencing and serves as the #1 protocol for nearly all IP-based video systems.