Video Conferencing : Equipment Sales | Networks - ISDN and IP | Public Room | Webcasting | Conference and Rental Services
Information on Networks for Video Conferencing
Business-grade video conferencing can be handled over either ISDN lines (the switched digital network) or over an IP Network (LAN, WAN or Internet)
While IP networks are gaining popularity rapidly, over 50% of video conferencing is still handled on ISDN lines around the world. Equipment running on different types of networks can be connected through a Gateway.
The inherent advantage to using ISDN is security. With IP networks, security can be improved through encryption.
ISDN-based Video Conferencing
ISDN (Integrated Services Digital Network) lines are digital lines working over a switched network - like your regular telephone line - only much faster. The video conferencing standard is H.320.
- One ISDN line, called a BRI (Basic Rate Interface), has two channels (therefore two telephone numbers) running at 64 kilobits each. Combining three (3) ISDN lines will provide 384 kbps of bandwidth - which is the generally-used standard for business quality video conferencing. ISDN-BRI is provided by your local telephone company.
- ISDN is also provided through PRI (Primary Rate Interface) lines. PRI's are essentially T-1 lines that have 23 channels running at 64 kilobits each. Some video conferencing equipment can take a full PRI. Usually a PRI is separated so that some channels are used for video conferencing, and some for either voice or data. PRI's are provided by the local telephone company as well as long distance companies.
IP Network-based Video Conferencing
IP Networks are quickly gaining popularity for H.323 conferencing. The primary advantage over ISDN is that there is no additional charge for long distance. This is particularly important with international video conferencing.
The challenge for IP Networks and video conferencing is to manage the latency and jitter so the quality of the picture is acceptable. For LANs and WANs, the necessary Quality of Service (QOS) can be managed by your IT Group, though it may require additional equipment and software upgrades.
While connecting over the Internet is possible, the picture and sound quality is not totally reliable for video conferencing.
Managed Networks
Many companies are finding value in the services of Managed Network Providers. These companies provide Service Level Agreements on the network, guaranteeing QOS necessary for video conferencing. Even if you already have data networks between your various locations, it may be preferable to use an OVERLAY managed network arrangement for a combination of video conferencing, voice-over-IP, and overflow to the Internet.
Video Conferencing Equipment for IP Networks
Both Tandberg and Polycom provide excellent equipment IP Networks.
For lowest-cost video conferencing on your computer and over the Internet, popular arrangements include Microsoft NetMeeting running on a Pentium III or higher with web camera and microphone, over broadband. However, the size and quality of the picture are limited, even with cable or ADSL connection to the ISP. Polycom also offers the low cost Via Video system ($550 each end), which is compatible with all H.323 standard equipment.