There've been some interesting discussions recently about the role of presence in unified communications, and of course I want to put in my two cents. I strongly agree with what Zeus and Irwin wrote about presence (yes, sometimes analysts agree with each other) - presence is key, it is core, it is the dial tone of the 21st century, yada yada.

There've been some interesting discussions recently about the role of presence in unified communications, and of course I want to put in my two cents. I strongly agree with what Zeus and Irwin wrote about presence (yes, sometimes analysts agree with each other) - presence is key, it is core, it is the dial tone of the 21st century, yada yada.When I measure the UC market in my new report, "Enterprise Unified Communications 2007-2012", one of four methodologies I use is to identify which UC elements must be present in order to be considered a UC solution. There are several elements or components that make up a UC solution, but not all of them are required in a UC solution - you can have a UC solution that does not include unified messaging or conferencing, for example. There are only a few requisite elements for UC, and presence is one of them. Of course there are different types of presence - in the UC world, presence capabilities can refer either to IM or online presence or to telephony presence (indicating if someone is onhook or offhook). In mobile UC applications, presence may be based on the mobile device being turned on or off.

The role of presence in UC cannot be understated. I wrote about presence quite a bit in my report - here are excerpts from various sections that discuss presence and UC:

The cornerstone of unified communications is presence. Every aspect of collaboration requires or is enhanced by knowing whether colleagues are available for a communication; how to best contact and interact with them based on what device they are using; and what their situation and circumstances are (in a meeting, at a customer site, etc.).

From a section on some of the challenges of UC:

For UC to be used successfully outside of the enterprise walls to customers, partners, suppliers, and others, federation is required across different types of IM services, and across different presence/IM servers and systems from different vendors (whether Microsoft, IBM, Cisco, Avaya, Alcatel-Lucent, etc.). For presence to be effective, it needs to work in a multivendor environment, especially when being used across company boundaries. This can happen either by system-to-system communications or by linkages to a central clearing house, and either way will require adoption of standards.

From a section describing the role of presence when analyzing and estimating the UC market:

Presence is the heart of the UC solution, and includes both the server software and clients in this analysis. The role of the presence server will increase over the next few years, as more and more capabilities are migrated to the presence server. For example, several vendors provide conferencing/collaboration capabilities on their presence servers.

The Presence category will evolve in two ways. At one level, it will provide user productivity to all types of users within an organization, and the platform will expand to include a wide range of capabilities, including IP Telephony. In some cases, the Presence servers will replace the IP PBX, either for departments or for the entire enterprise. For example, Microsoft's Office Communication Server (OCS) is seen by some as an "IP PBX replacement," and some companies are using OCS for their call routing and telephony capabilities. In three-to-five years, enterprise customers who need to replace their existing switches may instead use their OCS system for call control. We expect that for some small- and medium-sized companies, as well as in departments of large organizations, products such as OCS and IBM's Sametime will eventually be used in place of the PBX.

So not only is the role of presence key, it is THE key to unified communications. But there are certainly challenges, and until there is true interoperability and federation of presence capabilities, UC will be effective for intra-company communications, but not for inter-company communications with customers, partners, suppliers, and others. We've come a long way, but much work is left to be done.