Multi tree database architecture consists of a number of distributed database subsystems (DSs).

Databases are DB0, DB1and DB2.

Some numbers of DB2 databases are grouped to one DB1 and some of the DB1 databases are connected to single DB0.


Registration request message is sent to the associated DB2 then it sends a registration request message to the DB1 controlling this area.

It register the new DB2 in the index entry and it updated to old DBO.

In the DB1 also it not exist it moves to DBO for checking and the call delivered.

Existing system


In global roaming, general database design is used to implement.

Location tracking is based on two types of location databases:

*Home location register (HLR)
*Visitor location register (VLR).

The profile contains information such as the service types subscribed, the user’s current location, etc.
A VLR is centered with a mobile switching center, controls a group of registration areas.

Whenever area changes, HLR are updated to the new location and deregistered from the old VLR.

In the future mobile networks, the updating and querying loads on the location databases will be high.