My good friend Don Van Doren wrote an excellent blog last week on the importance of interoperability in UC; it was a follow on to an earlier piece by Fred Knight. As usual Don made a number of interesting points, particularly regarding the deficiencies of the current incarnation of presence, one of the "Cornerstones of UC." What struck me most was a feeling I've had about presence for some time: This is designed for a planet I don't live on.Two of Don's points stuck out. First is the impracticality of having people update their presence status manually; it's simply not going to happen. Second is the requirement that the user be able to manage their availability status differently for different contacts. These are very practical issues that deal with how (or "if") people will incorporate presence capability into their work routines. If the presence status is consistently incorrect users will simply ignore it, so unless these deficiencies are resolved, the likelihood of mass adoption is nil. Fortunately, we in the mobility space have some ideas to contribute.
As far as I can see, a manual process for presence updating is a non-starter. UC platforms can typically change the user's presence status based on calendar entries, but most of us are dragged into countless ad hoc meetings during the course of the day, so we need a solution that is more dynamic and does not require action on the user's part. Also, when was the last time you were at a scheduled meeting that actually ended on time? On/off hook status from the PBX is a key indicator of availability, but "who" you're talking to is also a determining factor. Further, without the ability to see the status of the user's mobile, we still don't know very much.
The one element that might make presence plausible is the ability to tie in location with these other metrics. Where the user is can tell us a lot about their availability. If the person is in a conference room and their calendar says they're scheduled for a meeting, we should be able to put two-and-two together. The most interesting add-on to calendar-driven presence I've seen comes from Zeacom. In their UC solution, when a user touches the keyboard or mouse on their desktop PC, the system can change their status to "in office."
The key element is that people don't go anywhere without their mobile phone, so if we can find the mobile we can find the user. There are three potential elements in the mobile we might use to determine location, and a number of different location technologies that can be used to track them. A workable solution will require a combination of these as each has a different profile regarding coverage, accuracy, and battery draw.
* GPS/Assisted GPS: Very accurate and available on many mobile devices, but long initial location time (i.e. "time to first fix"), virtually no indoor visibility, and a significant battery draw.
* Cell Tower Location: Not as accurate as GPS (accuracy depends on the size of the cells in that area), but more power efficient, and with a database of tower locations you can determine the city the user is in and record regularly visited locations like your office in that city.
* In-building Wi-Fi Location: This requires a mobile device with a Wi-Fi interface and a location appliance (e.g. AeroScout or Ekahau) on the wireless LAN. These systems can provide resolution within a few meters, but Wi-Fi is also something of a power hog, so iPhone users have found it's best to turn it off when not in use. Also the Wi-Fi radio has to send something in order to be seen.
* Wide Area Wi-Fi Location: Skyhook Wireless has a Wi-Fi Positioning System (WPS) that uses a database of over 100 million Wi-Fi access points they have recorded; this is the location service used in many iPhone applications. The device receives beacon messages from visible access points, send the access point's address (i.e. BSSID) to Skyhook, who returns the location coordinates. Used either alone or in conjunction with GPS, WPS combines speed and accuracy, but it too requires a Wi-Fi radio.
* Bluetooth: Generally overlooked as a location technology, if your mobile device has a Bluetooth interface, we can find it. To demonstrate that Bluetooth tracking could work, researchers from Bath University tested a Bluetooth tracking system called Cityware in the city of Bath, England last year to determine how people moved about in cities. For privacy reasons that system did not seek to identify individuals, but such a capability could be added by registering each mobile device's Bluetooth Device Address. If the mobile is registered with a desktop PC or PBX station, we can surmise that the user is within 10m of their office (i.e. the typical transmission range of a Class 2 Bluetooth transceiver). There is also a Bluetooth location tracking (BLT) protocol, so "promiscuous" Bluetooth transceivers could be installed in conference rooms, the cafeteria, or near building exits.
Most of these solutions are handset-based, so the handset will know where it is, but we also need a mobile data capability so the handset can tell the presence server. Network-based location solutions like in-building Wi-Fi location systems will also need to interface with the presence server that will set the presence status (or prompt the user to determine if the status change is warranted) and then make it known to others based on the availability rules the user has defined.
Conclusion What got all of this started was the requirement for interoperability in UC, and what we are seeing is that requirement goes far beyond PCs, phone systems, and UC platforms. Presence truly is one of the core capabilities of UC, but users are busy, they're often on the move, and they are not going to adopt a capability that's more trouble than it's worth. A location capability, based in the user's mobile device be it cellular, Wi-Fi, or dual mode, can be the key to making presence workable. However, if we need to determine location both in and out of the office, a multi-modal solution will be required. Bottom line, if this UC thing is going to fly, we've got to tailor it to the way work happens in the real world, and there's a lot that needs to be done.
