Everywhere you turn it seems there is another ad for Vonage a VoIP-based phone service (define) that uses a broadband connection to save money on calls. Even the traditional telephone and cable companies are starting to push the service. The technology of VoIP itself is not new telephone companies have been using it in their own backbone for years. What is new is rolling the service out direct to end users.
But there is another aspect of VoIP that is more important from a business standpoint. Replacing existing internal phone systems with VoIP networks can cut costs, simplify administration and enable a variety of new applications that improve collaboration and productivity.
From Analog to Digital
VoIP represents the latest in a long series of actions to change voice transmission from an all-analog to an all-digital process.
The analog system has a tremendous quality of service built in. It assigns a dedicated end-to-end connection for each pair of users, with separate channels to allow simultaneous two-way transmission. Those lines could carry a lot more than just two people's voices but they don't, thereby wasting a lot of potential bandwidth. Standard phone service is like having your own limo waiting outside your door with the motor running ready to take you anywhere on a moment's notice. It is very good service, but also not very efficient.
VoIP, on the other hand, allows many voice transmissions to pass over the same piece of copper or fiber by dividing the communications into packets and then routing these packets, mixed in with those from other users, to the other person in the conversation. VoIP is like having a fleet of shared taxicabs. It makes very efficient use of the available resources, but you still may end up standing in the rain trying to catch a ride.
IP networks (define), after all, were not designed with the same quality of service in mind as phone systems. In fact, the architecture anticipates that some packets will get lost or delayed along the way and contains procedures to request the retransmission of any missing packets. From a data standpoint, this may mean that the user has to wait an extra second or two for a web page to download.
But voice transmissions can't work that way. To be effective, it requires a continuous stream of data. You can't have a random series of three-second delays happening in the middle of a sentence and still have an effective conversation. This proved to be a major barrier to the widespread adoption of VoIP.
To guarantee an adequate level of service, the International Telecommunications Union (ITU) has approved standard H.323 (define) which sets out standards for voice, video and data. The implementation of H.323 by manufacturers and carriers brings VoIP quality up to the level of older switched networks and opens the door for its widespread adoption.
Phasing It In
The aspect of VoIP being widely promoted right now is using an Internet connection to replace traditional phone lines. From an IT standpoint, however, what is important is how it can facilitate internal communications. To begin with, it means only one set of wires that have to be strung to the desktop since the computers and phones will both just be nodes on the same network. It also means that staff only needs to support a single transmission protocol.
The real value, however, will be in the area of converged applications that VoIP enables.
"In two years we will be seeing a critical mass of applications in this area," says Gartner vice president Jeff Snyder. "These applications are what are going to make the compelling argument for switching to IP Telephony."
First of all, it brings voicemail, e-mail and faxes into a common inbox where they can be deleted, answered, forwarded or saved. They also provide presence management the ability to see who else is logged onto the network at the time.
In a call center or help desk situation, for example, an analyst or agent can then escalate a call simply by finding who else is available and transferring both the caller and all supporting data or documents to that employee. This reduces the number of callbacks and improves customer service.
They also make teleconferencing, including document sharing, a standard desktop and telephone feature, rather than something that needs to be specially scheduled. Just clicking on an icon brings additional participants into the discussion. Certain telephony vendor including Avaya, Mitel, Nortel Networks and Siemens already offer some of these features, but getting to the point where they can be used in smaller businesses will take a bit of work.
To begin with, the network needs to be robust enough to handle the additional load and provide an adequate level of service. This means testing, modeling and, if necessary, building out the network so that it can handle the traffic. Remember, if the network is down, people can't use their computers or phones.
Next, it involves replacing the existing telephony hardware and software including switches, private branch exchanges, voice mail, answering system, and the like. The traditional PBX (define) vendors Avaya, Nortel, Mitel, Alcatel, Siemens, networking companies Cisco and 3Com, and specialty vendors such as AltiGen, Shoreline Communications and Vertical Networks all have products that support VoIP.
Finally, all the telephone handsets need to support VoIP, which can be purchased from any of the vendors listed above.
Pieces of the Puzzle
If provisioning a new office and building a network from scratch, you should go ahead and put in VoIP, providing, of course that your mission critical applications will work on the platform. But for most organizations that already have an adequate phone system in place, Snyder recommends waiting until it is time to refresh existing switching hardware. After that they can gradually add the other pieces of the puzzle.
"First they buy a switch from their legacy vendor so they can run all their old systems on the new box; then they buy the data network; then they upgrade or replace their applications including any custom integration; finally they phase in the new telephones," Snyder explains. "That way they have the ability to spread the cost out over several years as appropriate."