Video Conferencing 101: Network Fundamentals for Smooth Video

In order to set the company up to be capable of adopting video conferencing technology, certain network requirements have to be fulfilled. At the simplest level (also known commonly as web conferencing), video conferencing can be made possible with a broadband connection, a proper microphone and an instant messaging system that comes with the video call capability. But for enterprise level video conferencing, more is expected. This is because corporate video communications require a smoother flow in correspondence in order to serve their purpose. You don’t want to get cut off from talking to a client halfway through your presentation.

Enterprise Network Requirements

For this collaboration technology, video conferencing can leverage on existing public telephone network, a private IP network or the Internet. The target bandwidth for interactive video communications is in the 300K to 400Kbits/sec per connection between local and far-end parties.

In video conferencing, bandwidth is assumed to be symmetrical. That means upstream (video transmission speed) and downstream (video receiving speed) shall have the same bandwidth.

Thus, before start of deployment, you need to estimate the number of simultaneous sessions your network needs to support (also cater for immediate future expansion), and figure out if your network has bandwidth end-to-end.

For smaller operations (only a single simultaneous session), DSL or cable modems could work although it is not guaranteed that commodity Internet – a connection used and shared by different subscribers – could support minimum bandwidth requirements for smoother videoc onferencing

Firewall Issues

Firewalls are designed to keep out certain types of traffic out of a network to keep the enterprise safe from malicious intent. They are usually deployed in strategic points between the public and corporate networks.

In normal circumstances, video conferencing traffic will be blocked on firewalls preventing two-way audio and video conversations. If the firewall is not H.323 aware, you will likely need to open select ports. You will have to open both TCP and UDP ports which will be specified by the equipment manufacturer.

Alternatively you may locate the video conferencing system in a DMZ (Demilitarized Zone) for easy work-around. However this will introduce a glaring gap in the network security and is not highly recommended.

For enterprise with several systems, one way to get around firewall blocking issue is to deploy a H.323 Gatekeeper. Once all the video conferencing endpoints are registered with the Gatekeeper, firewall-traversal can take place between the endpoints.

Dedicate VPNs

VPN (Virtual Private Network) is also being used at some organizations to simulate ISDN connectivity and at the same time provide some form of security. In order to use VPN for video conferencing, some of the challenges have to be considered.

VPN is strictly point-to-point connection and is only suitable for a single session between 2 parties. Hence its usability is limited and cannot cater for multi-parties video conferencing. Also each connection requires user and password management which means extra administrative efforts. VPN connectivity will introduce extra overheads and it may affect latency of the video conferencing session.

At SG Videoconferencing, as part of our value added service; our in-house video and network consultant will do an in-depth study your existing network infrastructure and topology. Once that is done, we will recommend the most suitable network technology that gives the best video experience.