The next phase of voice over IP will be built on a foundation of presence management and instant messaging, two of the most powerful elements not only of VoIP but also of the session initiation protocol overall. In a VoIP world, SIP is the driver for widespread business upheaval and transformation.

Presence and IM will usher in the era of the always-on environment. The user interface will migrate from the phone to the PC. New controls and capabilities will eliminate users' history of frustration and diminished expectations of reaching people.

The concept of “making a call” will become a legacy notion, a vestige of the TDM world. In the always-on environment, users will be continuously connected via fixed-rate broadband, with conversations easily initiated by IM. Presence management will let users know there is high probability of establishing the call. And the telco billing machine as we know it will evaporate.

In the always-on environment, mobility products will be interwoven into the enterprise market, evolving into another SIP-enabled IP endpoint. There is already such a strong demand for mobility access that many enterprise customers now print their wireless numbers on their business cards, a tacit admission that enterprise phone systems can't integrate to meet mobility needs.

TDM-based communications require huge feature sets, largely to compensate for the inability of connecting the caller to the called party. In the always-on environment, presence and IM let users know when parties are available and by what means. Voice mail becomes a deliberate choice, not a signal the caller failed to find their party. And with the PC as a core vehicle, conferencing multiple parties together becomes much easier and more capable, vastly improving the ability to share data via multiple media.

The opening salvo in this emerging environment will be the arrival of Microsoft's enterprise Live Communications Server. Microsoft's entrance will validate enterprise IM for hundreds of thousands of businesses and make it easy to install and integrate. And Windows XP is already SIP- and VoIP-enabled, allowing the potential to tap into a vast, dormant but fertile universe.

SIP shifts power to the user via intelligent endpoints with unprecedented power and capabilities. The balance of power is transferred from monolithic phone systems to individual users. This puts the largest players in the desktop at the head of the power curve, which may blur or destroy the distinction between enterprise, SOHO and personal applications for VoIP. Once users receive powerful, flexible, customizable and intelligent endpoints, the possibilities for what they will want to do with it are endless.

DOSSIER NEAL SHACT

Occupation: CEO of CommuniTech and community developer for the International Packet Communications Consortium

Location: Chicago

Favorite Web site: www.nytimes.com

Current reading: “The Fountainhead” by Ayn Rand

Device inventory: Motorola MPX200 Smartphone

What's on your iPod?: Nothing yet — I just received it last week for my birthday

What's next: An article about why VoIP and broadband are a matter of national security and energy independence and deserve greater support from the government