Mobility is the new reality of business, and stands to have a tremendous impact on the implementation of unified communications (UC). One of the key features -- and persistent problems -- of UC is presence, or
Location-based presence is based on the idea that if you know where people are, you can intuit a significant amount about their reachability, particularly if the location information is combined with other metrics. For example, if the location system indicates that they are at their desk and using their computer, they're probably available; if not, they can respond with a quick "Do Not Disturb" message, which can change their status to "Busy." If they are in the office and we determine they are in a conference room, we can guess they are "In Meeting," particularly if their calendar shows a meeting scheduled at that same time.
The mobile industry has come up with a number of location-based technologies that enable mobile presence. People are rarely without their mobile phones, so if we can find the mobile phones, we can find users. Those capabilities are more prevalent in smartphones than in basic handsets, particularly if the smartphone also includes Wi-Fi capability. Tablets are also finding their way into the enterprise, and provide an alternative trackable element. These techniques vary with regard to the mobile technology they depend on (e.g. Wi-Fi, cellular, Bluetooth), coverage area, accuracy and battery draw. A fully functional solution may require a combination of these techniques.
- GPS/assisted GPS: Very accurate and available on most mobile devices, but even assisted GPS suffers from a long initial location time (i.e. time to first fix), poor indoor visibility and a significant battery draw. However, self-reporting (as opposed to network-based location) typically requires an application in the device, and that is generally limited to smartphones.
- Cell tower location: Not as accurate as GPS (accuracy depends on the size of the cells in that area), but it is more power-efficient, and if nothing else, you can determine the city the user is in. You can also record the towers near regularly visited locations like your office. When that location is stored in the presence database, anyone who shows up on that same tower (as reported by the location app in their phone) is assumed to be in "Chicago Office," for example. They might not be, because that tower could cover a few square miles, but you'll be close. Again, self-reporting is typically restricted to smartphones.
- In-building Wi-Fi location: This requires a mobile device with an active Wi-Fi interface and a location appliance (e.g. those from AeroScout or Ekahau) on the wireless LAN. These systems can provide resolution within a few meters. This technology can track any Wi-Fi-equipped device (including smartphones and tablets) as well as Wi-Fi tracking tags.
- Wide area Wi-Fi location: Skyhook Wireless developed 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, sends the access point's address to Skyhook, who returns the location coordinates. Google has been developing a similar Wi-Fi location database, though their collection methods did ruffle some feathers.
- Bluetooth: Generally overlooked as a location-based technology, if your mobile device has a Bluetooth interface, we can find it. In an enterprise UC environment, if a user's mobile is registered with their desktop PC or PBX station, we can surmise that 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.
Whatever mechanism we employ to locate the user, whether it's based in the handset or the network, we need some mechanism to relay the location information to the presence server, which in turn updates the user's presence status.
Enterprise UC suppliers seem to understand that location is important, but have done little to address it. IBM's Sametime lets remote users register the location where they connect to the network and subsequent users who log in with the same IP address can be identified as being in the same place. That pins location down to a city or potentially a building. Microsoft Lync 2010 includes a location capability, but it only works if users are connecting via Wi-Fi and can only locate them to an access point (i.e. an accuracy of around 10,000 square feet). Neither of those capabilities is tied to presence status.
Embarrassingly, consumer services like Facebook and Foursquare recognize the location capabilities of mobile phones and are building new services based entirely on that capability. So while your UC system may not be able to pinpoint your location, maybe Foursquare can make you "mayor" of your office. Google got off to a slow start in location, but recently appointed one of their stars, Marissa Mayer, vice president of search, to head up the company's location-based initiatives. Google has made a start with Google Maps, but they are banking on the fact that location coupled with search will allow them to build revenue-generating services in conjunction with business or other highlights that are in your area.
Presence is one of the core capabilities of UC, but users are busy, they're often on the move and they will not use a capability that's more trouble than it's worth. Further, if presence turns out to be an unreliable mechanism to determine availability, users will simply ignore it or continue to use tried-and-true methods ("U thr?"). Location-based technologies are one of the most significant developments in mobility, and as users are rarely without their mobile devices, locating those devices will be the key to locating the users. The bottom line is, if we want integrated communications, we'd better start addressing the practical issues. Fortunately, the consumer mobile offerings show us the path.
About the author:
Michael Finneran is an independent consultant and industry analyst who specializes in wireless technologies, mobile unified communications and fixed-mobile convergence. With more than 30 years in the networking field and a broad range of experience, Finneran is a widely recognized expert in the field. He has recently published his first book, entitled Voice Over Wireless LANs -- The Complete Guide (Elsevier, 2008). His expertise spans the full range of wireless technologies, including Wi-Fi, 3G/4G cellular, WiMAX and RFID.
This was first published in November 2010