Already, experts say early VoIP adopters have suffered voice-line outages. For example, a Merrill Lynch manager of voice product development said at a major VoIP conference last fall that e-mail viruses including Sasser and Code Red took down the company’s VoIP network for two to four hours because it rode on top of the data network. Darrell Epps, director of the convergence and IP telephony professional services practice for NextiraOne, a consulting and integration company, confirms that some Fortune 500 companies using VoIP have already suffered from VoIP hacking incidents that have hurt company operations.

For many organizations, however, the low cost and convenience of VoIP outweigh the potential security risks and possible phone outages. Despite its previous voice-line outage, Merrill Lynch recently signed deals with Cisco and Avaya for extensive VoIP rollouts in its headquarters and branch offices. (Merrill Lynch officials did not respond to a request to be interviewed for this story.)

In addition to saving money on long-distance calls and intra-office calls, VoIP users say they will also economize by managing one converged data network instead of separate voice and data lines. VoIP is also expected to bring multimedia services to the desktop and, in some cases, improve customer service. For example, customers trying to reach a Web-based, VoIP-enabled call center would be able to click on a hyperlink to start a conversation with a live service agent. And traveling employees with VoIP can make and receive calls from their home office numbers via their laptops.

Prepare for Safe Dialing

For Steve Novak, CIO at the Chicago-based law firm Kirkland & Ellis, VoIP technology isn’t new. In his previous role at 3Com, Novak was part of the team that made one of the country’s first-ever VoIP calls at a Las Vegas trade show in 1997. "We set up an old Bell phone booth on stage and the call worked," Novak recalls. "People were stunned and I remember thinking at the time that the technology held a lot of promise."

Since becoming CIO at Kirkland & Ellis, however, Novak has taken a cautious approach to VoIP. Instead of moving quickly to install the technology throughout the law firm, which has offices in seven cities around the world, Novak and his team decided to move slowly and use VoIP on calls only within the company at first. VoIP security experts suggest that those new to VoIP take Novak’s approach by implementing the technology within their organizations in a slow, phased process. Then, by the time they introduce the riskier public network connections, they will be more familiar with the technology.