Mapping the GSM landscape

SVG Open 2005

Goal

• Location determination– Best effort– Automatic

• Take whatever is available:– GPS

Accurate, but requires hardware and has limited battery life

– Wifi / BluetoothCheap, but ad hoc

– Mobile networks (operator based)No extra hardware, but operator dependency and expensive

– Mobile networks (central registry)Operator independent and cheap, but limited coverage.

Cell-id database

• Central data source with cell information– Converts cell-id into location– Based on multiple measurements– All automatic GPS measurements– Free to use, but expect new cells in return– User is also contributor– Easy access via web services– Focus area: western Europe

• Alternatives:– cellspotting.com– placelab.org

July 2005 statistics

• 10389 cells of• 35 operators,• 264051 measurements in• 14 countries,• 57 provinces, and• 229 postal code regions

• And growing every day…

Possible applications

• The well-known Friend Finder– Add location information to instant messaging– Like MSN adds the now-playing-track from

MediaPlayer to the contact/buddy details• Speech recognition of street and city names

– Limit the degrees of freedom in the solution space• Voice gateway

– Call a fixed number to get information about items in your vicinity (attractions, ATMs, toilets, history,…)

• Bad connection marker– Predict bandwidth drops in advance for streaming

application

Searching for a new home

• With one click an overview of all homes in the vicinity• Without GPS but based on GSM cell location• Integrated with Funda.nl

Where are my friends and colleagues?

• Exchange context information with relations• Reason with context information

• Frequently visited places• Predict destination• Business travelling• In a meeting• In or out the office

Demo!Demo!

An impression…

If you want to use the cell-id database

An easy 4-step process:

• Get an impression of what is there:http://www.lab.telin.nl/~koolwaaij/showcase/gsmcells

• Sign a license and get the credentials from:koolwaaij@telin.nl

• Access the webservice to convert cell-id into lat-long:http://client140.lab.telin.nl:8080/wasp/services/CellStoreService?wsdl

• Generate the client stubs and use them in your application, use standard HTTP authentication

Code sample in C#

• Create a new project• Add a web reference to the cell store service• Call the web service:

CellStoreService myService = new CellStoreService(); myService.Url = "http://server.nl/service";myService.listCells(204,8,false);

• Returns a CellData[] with all cells for operator 8 (KPN) in country 204 (The Netherlands).

It is as easy as that!

Thank you!

http://www.telin.nl

Johan Koolwaaij

koolwaaij@telin.nl

August 2005