Identity and Location
When I took my sons camping last weekend, David brought along his Mac laptop with a GPS antenna and mapping software. As I drove, he tested out the software to see how well it tracked us as we travelled to our destination through the Arizona countryside. GPS, like the Internet, is a superb technology that has filtered down to the general population from the military applications for which it was originally designed. Moreover, it is a really fun toy.
We chuckled when it displayed a few commercial landmarks, like the McDonalds restaurant at the junction of Highways 87 and 260 in Payson, AZ. We were amazed at how accurately it tracked us along a dirt road that wound through the woods northwest of
Tonto Village. However, at times when we drove along a fairly new stretch of divided highway, the arrow on the screen which represented our vehicle showed us meandering off the known highway through the sajuaros and mesquite.
It occured to me that Location can be a dynamic and useful attribute of Identity. At any moment a GPS-equipped vehicle or person can have fairly precise location attributes associated with other unique Identity information. Location differs, however, in its dynamic nature. As long as our car was moving, the location coordinates (latitude, longitude, elevation) for our vehicle changed correspondingly.
Earlier last week, I read attended a telebriefing and read a new white paper from the Burton Group about
Virtual Directory Services (VDS). Location is a good example of an attribute that is not easily stored in a classic directory. It would be a poor practice to continually update a vehicle’s location attribute in a classic directory server along with less-frequently changing attributes. However, if an LDAP query could trigger a VDS query to a GPS-enabled location service, location attributes could be returned with along with other static attributes as if all were stored in the directory.
Including Location as a standard Identity attribute, can be a powerful addition to a wide variety of applications.
Location based applications – used in such industries as transportation, emergency services and law enforcement – could benefit directly from VDS – combining the dynamic nature of GPS and flexibility of directory services.
As for the mismatch between our dynamic location and the changing Arizona road? I think someone needs to update the map.
what gps and mapping software did he use?
My son said the GPS receiver is a USB-enabled Rikaline 6010, and the mapping software is Route 66 USA for Mac.
Interesting post. Location is certainly an attribute of identity; in fact, Liberty published the ID-SIS Geolocation Service Specification in April this year. The Geolocation Service makes a user’s current location available (with the user’s consent, of course!) to other web services. So, for example, wireless subscribers could receive a daily SMS on their cellphone giving them the weather forecast for their current location.
Thanks, Pat, for the information. I appreciate your comments.
And, tell us again, why would it be “a poor practice to continually update a vehicle’s location attribute in a classic directory server along with less-frequently changing attributes”? That may have been true in the olden days, but today’s directories routinely handle relatively frequent updates. If these attributes aren’t indexed (driving the update to a much higher level of cost) and the updates were “relatively” infrequent (minutes/hours or a few times a day), most directory servers should be able to handle it.
For real fun, help your son get his amateur radio license (ham ticket) and hook that GPS up to a small transceiver and start playing with APRS for near-real-time reporting. … Hmm that’s an idea … an APRS driven LDAP directory updater for my friends out here 🙂
Marty:
Thanks for your comments. The whole issue of whether GPS coordinate data should be updated in the directory is a matter of what “relatively frequent” means. In some cases, where the object of interest moves slowly or infrequently (e.g. the vehicle that moves the space shuttle to the launch pad), updating a directory is no big deal. However, if I want to track the location of a Life Flight helicopter because my kid is being transported to the hospital, updating location every few seconds may be necessary, but can generate a lot of overhead. Like many things, knowing the real requirements of an application can help us deal with inevitable performance/price tradeoffs. I suggested VDS as one means of addressing the issue of rapidly-changing location attributes.
On the subject of a ham license …
Twenty nine years ago, I was given the book “How to Become a Radio Amateur” by an uncle who desperately wanted me to join him in the ham ranks. I never took the plunge into the ham world, but still have the same lovely wife!