The pin:// Protocol has been developed to provide a method of pinning a document link to a GPS location, and provide a simple and intuitive standard interface for searching for document links. The pinServer has been designed to allow small footprint GPS aware devices to register themselves in a DHT network and share the registration database.
Please see pin protocol first draft : https://dl.dropboxusercontent.com/u/32643618/pin%20Protocol%20Overview.pdf