Saturday, July 10, 2010

Mobile telephony basics - Routing and Processing of data via Mobile phones

Location Based Services or popularly known as LBS is a current buzz in the Mobile telephony segment. Almost all major telecom players are providing LBS services to their mobile phone users. In this post I am going to discuss the LBS architecture  in brief and try to explain the working of Mobile Phone architecture.

The mobile phone handset operates on radio frequencies, that means the input and output data through a mobile phone is only in the form of radio waves when said on the most simplest terms. The data transfer standards are defined for bringing uniformity in data sending, receiving and to perform operation on the data generated by a user though the mobile phone. This standard or set of protocols is called as WAP. Wireless Application protocol. All phones send data using WAP. In internet the protocol is called HTTP - Hyper Text Transfer Protocol.

When we send any data via our phones it goes to the nearest Mobile Phone tower. From that tower it is send to the service stations where the telecom operators servers are kept. These stations have web servers plus application servers. before the WAP data format is fed into Web servers it has to be converted to HTTP format for processing by the application servers. This conversion of WAP data to HTTP format data is done via WAP gateway. Once this is done the user's request send via mobile phone is fed into the application servers and corresponding information is searched and returned which the user has asked. Again, when the information returned by application server is in HTTP format, it gets converted to WAP data format and then finally receives the mobile phone after getting routed through the towers.
Each WAP data sent via mobile phones contains some header info. This header info contains the location of the mobile phone where it is currently located as the mobile phone owner may continuously keeps changing locations. The location information of the mobile phone is registered in the tower where the mobile lies. The packet header is then routed to the corresponding tower after matching the packet header and the mobile phone current address registered in the tower.

This completes the cycle of request sending and receiving via mobile phones.