Daily Payload

H.323 Brings Video Conferencing to the Enterprise and Consumer Markets

July 19, 2009

As highlighted on Packetizer in June, there is a renewed interest in H.323 right now, largely thanks to the focus the industry has placed on video conferencing over the past year or so. While H.323 has enjoyed widespread success across the globe for VoIP communications, especially within the enterprise and inside carrier networks, H.323's raison d' être was to enable video conferencing over an IP network. Without a doubt, there is no other standard in the world with better support for video conferencing over IP networks, including various video codecs, far-end camera control, floor control, conference lists, and cascaded MCUs, than H.323. So, it is only natural to see this renewed interest.

Most H.323 devices have implemented a rich set of capabilities, allowing them to negotiate various voice and video communication modes and other features. That said, NAT/FW traversal was an issue for H.323 for a long time.

However, the ITU-T took up this issue as a formal study item and created two Recommendations called H.460.18 and H.460.19. They were defined in 2005 and, quite frankly, their acceptance in the market was not as widespread as expected. The reason for this is that most H.323 devices inside the enterprise, especially those used for video conferencing, were often isolated to LAN environments. The urgency to deploy a proper NAT/FW traversal solution was not felt by many developers and network operators.

With the increased focus on video conferencing, however, that is starting to change. People now want to connect their enterprise video systems with other enterprises and even users at home. As such, there is an increased interest in enabling consumer devices with H.323 capability, a market segment that has largely been ignored by manufacturers of H.323 equipment. For the consumer space, this absolutely means that NAT/FW traversal issues must be solved.

Last month, the team responsible for the GnuGK project released a new version of its gatekeeper software that supports the NAT/FW traversal standards H.460.18 and H.460.19. Further, support is now available in the open source H.323 stack called H323 Plus, formerly known as OpenH323.

What this means for the open source H.323 development community, as well as equipment manufacturers that rely on the open source H.323 stack, is that it is now possible to engineer solutions that enable consumers and small businesses to utilize voice and video conferencing services, even when those users are behind a NAT/FW device.

At the same time, the ITU is also working on two new Recommendations to improve on NAT/FW traversal support in H.323. These two new Recommendations, numbered H.460.23 and H.460.24, optimize the transmission of media between two devices. In general, use of these new standards will allow for an even more scalable solution that what is available today. What's more, the various open source development teams have already reported that support for these new standards is already being added to the open source products.

These recent events, especially with the market attention given to video conferencing, have given renewed life to H.323. While it is still the most widely deployed protocol in the world for both voice and video communication, much of H.323's potential had remained untapped due to the barriers presented by NAT/FW devices. We are now seeing those barriers come down.