If you want to learn more about audio conference bridge, you need to understand first how audio conferencing in general works...

The Internet has created several new ways for people to communicate with each other, from private text messaging to the World Wide Web, to people uploading video clips on YouTube. It's also revolutionized the art of the audio conference call, by replacing the dedicated audio conference bridge with cheap, commodity hardware running Voice over IP software.

Conference calls are nothing new - indeed, even as late as the 1980s, many rural locations had shared phone lines because the phone companies couldn't run switching equipment far enough. Since the 1930s, with the telephone circuit switch perfected at Bell Labs, doing audio conference calls through the Bell System has been an option for businesses.

Since the 1970s, many businesses had their facilities built with Private Branch Exchange (PBX and IP PBX) phone systems, allowing voice mail, dialing to extensions and conference calls.


How Audio Conference Bridge Works

What has changed is how the calls get switched around. What used to require dedicated infrastructure that involved rewiring entire buildings is now done with a server and Ethernet cable.

To an end user, Voice over IP (VoIP) audio conferencing works similarly to a traditional analog conference call. In a conference call, callers connect to an audio conference bridge, a server that allows multiple people to talk to one another. VoIP audio conferences use the same principle -- callers connect to a conference bridge via their telephones or computers.

Traditional telephones use circuit switching that routes calls through a series of interconnected switches until it reaches the audio conference bridge. The bridge connects the calls to one another.

One of the features of analog circuit switching is that all the connections stay open for as long as the call continues, though this can tie a network up considerably and results in the poor sound quality most people are accustomed to in conference calling. Further more, since only one person typically talks at a time, a lot of excess capacity on the network is lost with this technique.

With Voice over IP calling, the sounds are broken down into a small piece of data called a "packet". In much the same way that your email (or this web page) was sent to you, the packets are digital data that gets reassembled on the receiving end. Because of this, the network is only "in use" when a packet is going through it. This makes packet-based communications much more efficient in terms of infrastructure and allows you to use your existing Ethernet cabling solution or even a wireless solution in the office.

The other benefit of Internet based audio conferencing is that the audio conference bridge is essentially a small dedicated computer, called a router. The largest router manufacturer in the world for enterprise grade solutions is Cisco and they're one of the market leaders in audio conference bridges that are truly "plug and play" - put them on your network, configure them through a browser interface and switch your telephone system over to Voice over IP and you've now got an audio conferencing system for your office, for a fairly reasonable sum of money.

While that sounds simple in practice, it's definitely the job for trained engineers and specialists to do your switch over for you. While the hardware is a commodity item, the expertise for setting it up is not. Expect to pay consultants some hefty fees to get this to work - balance the prices they charge with the costs of doing international or business class airfares and the conferencing systems will pay for themselves in under a year.

Other vendors provide competing products, though few with the full range of features of Cisco. On the other hand, they're meeting different business price points with their audio conferencing bridges.

Chelston Communications Systems (http://www.chelston.co.uk/) provides conferencing solutions for businesses in the UK, including leasing the equipment, selling it outright and offering service contracts, as well as full service integration and switch over assistance.

Other vendors in the US include IVCI (http://www.ivci.com) and Sonexis (http://www.sonexis.com), which provide hardware purchase, support and leasing and integration and installation services.

Moving your business to a dedicated audio conference bridge is a sound decision that will pay off for you later, provided you take the time to research your needs and your clients needs.