Patent ID: 8428587

Claim:
A mobile communication system comprising at least a terminal receiving a plurality of types of services and a home agent receiving a position registration request from the terminal when the terminal moves, said mobile communication system, comprising: a home address holding function unit setting and holding a plurality of home addresses corresponding to the plurality of types of services, where one of these home addresses is designated as a representative home address and the rest as subordinate home addresses, a position registration request function unit, at the terminal side, creating a representative address set and subordinate address sets from the representative home address and subordinate home addresses which are acquired from the home address holding function unit and representative care-of address and subordinate care-of addresses which correspond to these home addresses, and the position registration request function unit further sending a position registration request to the home agent with the use of only the representative address set and a position registration function unit, at the home agent side, receiving the representative home address and subordinate home addresses which are acquired from the home address holding function unit, creating subordinate address sets from the representative address sets relating to the above position registration request, and registering the positions of the subordinate address sets simultaneously with the registration of the position of the representative address set.