Mobile Devices

Deployment Models

All mobile devices have different connectivity, storage, bandwidth, power and processing power capabilities. All location-based applications and services have different usage needs. Skyhook built XPS to support a variety of deployment models accommodating a broad range of mobile devices and location-based services. The XPS Architecture allows device manufacturers and application developers to select configuration options which can both support the native capabilities of the device and optimize the performance of the supported applications.

Deployment Models
  Autonomous Tiled Networked
Connectivity Periodic Frequent Always-on
Response Time 150ms 150ms 1-3 seconds
Storage Up tp 200MB 1-2MB Zero
Binary Size 1MB 800KB 500KB
Example Devices Personal Navigation Devices Dual-mode Phones Laptops

XPS Networked Mode

For applications that assume an always-on Internet connection like laptop/desktop-based web browsing, the XPS Networked Mode is ideal. This thin client mode simplifies the distribution of location-based applications but requires a constant network connection since all the data and calculations reside on the server. See the Loki and AIM case studies.

XPS Autonomous Mode

In Autonomous Mode, the XPS MLC is deployed on a mobile device with all the core components required to calculate location, to include all or part of the XPS reference database. Connectivity to the XPS Location Server is initiated every couple of months to update the locally stored data.

For mobile devices with ample storage space but limited network connectivity, like Portable Navigation Devices and Portable Media Players, XPS operating in Autonomous mode is the best option. See the iRiver case study.

XPS Tiled Mode

In XPS Tiled Mode, devices operate mostly off-line similar to the Autonomous Mode to conserve power and minimize bandwidth consumption but with a small set of reference data. XPS periodically downloads additional location "tiles" of reference data (e.g., single city or region) based on user movement and caches it locally on the device. This approach minimizes both the connection and data storage requirements.

For devices that have an always-on connection but need to conserve power, bandwidth and storage all at the same time, the XPS Tiled Mode provides the most flexibility. Dual-mode cell phones are ideal platforms for the XPS Tiled Mode.