Instant messaging worked its way into the corporate space as employees used products such as AOLs Instant Messaging service as a convenient way to get round email and voicemail over load and to find out whether the person you want to speak to is actually at their desk. In a similar vein, IT research firm Gartner predicts that by 2007 20% of all companies will have adopted plans that accommodate the fact that employees own the notebook PCs they use at work.

However, there is one exception to this trend, and that is Voice over IP (VoIP) or Internet Protocol Telephony (IPT) as it is also known. Companies such as Skype have done much to demonstrate the potential for VoIP to let people talk with each other across the globe for practically no charge. All the major ISPs and search engine sites (Google, Yahoo, and MSN) are rolling out consumer VoIP services. Yet with few exceptions, there is little sign that these consumer services are being used by people in the workplace.

There are a number of technical reasons for this, most notably the potential for consumer VoIP services to compromise the enterprise IP network security. However the primary reason is that the demands on the telephone in the office simply cannot be met by the somewhat cumbersome and restricted, point-to-point service offered by consumer VoIP services. Todays office voice communication systems feature call forwarding, voice mail, conferencing, hunt groups, hold and divert. These are not widely available in the basic consumer VoIP offerings. Furthermore, the PC-based VoIP offering does not provide the essential and convenient function of simply dialling a 10 to 12-digit number to make a call.

Enterprise VoIP products offer these features, and a whole lot more. With all messages data and real-time communications (such as voice, video and instant messaging) carried over the same IP network, there is opportunity for very rich communications sessions. For example, a colleague sends you an email within which there is an icon that lets you know that the colleague is available to take a call to discuss the content of the message. By clicking that icon, your colleagues phone rings and you talk; the colleague could be sitting at a desk anywhere in the organisation, or even at home on a broadband extension to the enterprise network, and the phone next to him or her would ring because the IP network knows where he or she is.

Cost is another major reason why VoIP cannot be lifted directly from the home to the workplace. To fully deploy VoIP in the office with all the new features of a converged IP platform, a company will be encouraged to spend money on new desk top devices; just as the consumer will have to buy a sufficiently fast PC and a headset to accommodate a consumer VoIP service. Most finance directors will struggle to sign off a business case to simply replace a serviceable piece of equipment (such as the company phone system) with something that for all intents and purposes does the same thing.

However, by implementing a gateway between their existing telephone equipment and the new VoIP services, businesses can realise the potential for external calls being carried over the Internet at vastly reduced costs compared to using the Public Switched Telephone Network. VoIP gateways convert the signals used by existing telephone equipment into those that can be carried and switched over the Internet. Many businesses are using VoIP gateways to connect to the new generation of IP-based phone companies or to carry calls between company sites for free using its existing wide area IP network.

It is only a matter of time before all communications, including telephony and mobile, are carried over IP and we will not be able to tell the difference between consumer and business VoIP just as we see little difference between a home phone and one in the office today. However, for the time being the two remain distinct propositions and the enterprise must be careful when considering deploying a consumer orientated VoIP service instead of one that is designed for the business need.