Convergence does not mean that the work and home identities at the center of the figure become one. In Ozzie's Groove software, these identities are distinctly separate constructs. Each binds to its own unique set of group memberships, devices, and shared data. What has converged is not the multiple identities of the user, but the mechanisms for device federation, group formation, data synchronization, awareness of presence, and change notification.
Easier said than done. For now, you have to drink the Kool-Aid served by the likes of AT&T Wireless, or Groove, in order to reap the benefits of convergence. When Microsoft offered up HailStorm, businesses said "no thanks" and put federated identity squarely on the agenda. What that means is open for discussion. Web SSO (single sign-on) schemes, including Microsoft's Passport, Liberty , and Shibboleth, are ascendant. But as the Midvale, Utah-based Burton Group CEO Jamie Lewis points out, they're not incompatible with PKI (public key infrastructure).
Arguably using name/password authentication within the enterprise and cryptographic certification across enterprises makes sense. Alternatively, the pervasiveness of strongly-identified personal devices — which, unlike humans, can remember cryptographic keys — suggests another kind of proxied PKI.
The long-anticipated, yet elusive convergence of voice, video, and data means for the enterprise more than a delivery vehicle for training. Telepresence is a power tool for identity management. If I can hear you and see you, I can authenticate you. A secure phone call or videoconference might lead, by way of a protocol such as SIP (Session Initiation Protocol), to a secure data channel. Our presence together on that call might, in turn, be observable — by my wife, or by your co-worker, or both — in an e-mail client or IM (instant messaging) buddy list. You can see a glimpse of this in today's Mac OS X Mail client, which displays IM presence indicators next to e-mail messages from AIM and iChat buddies.
Everything on the periphery of the figure — devices, groups, data types, communication channels — has been proliferating, and that trend will continue. Convergence can't and won't limit that diversity, but it can and must help us use it effectively. Identity is the key.