Data processing method for portable communication terminal and portable communication terminal

1. A data processing method for a portable communication terminal connected to a server over a communication network, comprising:

predicting a future change in a communication state of a connection between the portable communication terminal and the server based on a record of communication speed recorded in reference to the connection;

determining a terminal processing level indicating a level of data which is permitted to be held in the portable communication terminal based on the future change in the communication state that has been predicted;

determining an importance level for each type of data of one or more types of data; and

limiting data to be held in the portable communication terminal based on the terminal processing level that has been determined and on the importance level that has been determined for each type of data.

2. The data processing method according to claim 1 , wherein when it is predicted that the communication state will be improved, restriction is made so as to decrease data to be held in the portable communication terminal.

3. The data processing method according to claim 1 , wherein when the terminal processing level is changed by a change in the prediction result on the communication state and, in the portable communication terminal, there is update on data whose importance level is changed to an importance level which inhibits the data from being held at the changed terminal processing level, the update content is reflected on the server and the data with the changed importance level is then deleted from the portable communication terminal.

4. The data processing method according to claim 1 , wherein when it is predicted that the communication state will be deteriorated, restriction is made so as to increase data to be held in the portable communication terminal.

5. The data processing method according to claim 1 , wherein when the terminal processing level is changed by a change in the prediction result on the communication state, data whose importance level is changed to an importance level which permits the data to be held at the changed terminal processing level is read from the server and copied into the portable communication terminal.

6. The data processing method according to claim 1 , wherein in predicting a change in the communication state, positional information and movement information of the portable communication terminal are acquired, and

the acquired information are used in predicting a future change in a communication state in connection with the server.

7. The data processing method according to claim 1 , wherein upon reception of a data read request,

it is determined whether or not the determined terminal processing level is equal to or higher than an importance level given to data to be read out which is indicated by the received read request,

when it is determined that the determined terminal processing level is equal to or higher than the importance level, the data to be read is read from the portable communication terminal, and

when it is determined that the determined terminal processing level is less than the importance level, the data to be read is read from the server.

8. The data processing method according to claim 1 , wherein upon reception of a data write request,

it is determined whether or not the determined terminal processing level is equal to or higher than an importance level given to data to be written which is indicated by the received write request,

when it is determined that the determined terminal processing level is equal to or higher than the importance level, the data to be written is written in the portable communication terminal, and

when it is determined that the determined terminal processing level is less than the importance level, the data to be written is written in the server.

9. A portable communication terminal connected to a server over a communication network, comprising:

a terminal data storage section that stores an importance level of data to be held for each type of data of one or more types of data;

connection state prediction judging section that predicts a future change in a communication state of a connection between the portable communication terminal and the server based on a record of communication speed recorded in reference to the connection;

terminal processing level determining section that determines a terminal processing level of data to be processed in the terminal itself based on the future change in the communication state that has been predicted by the connection state prediction judging section; and

a data access managing section that, when it is necessary to gain access to data that resides on one of the server and the portable communication terminal, determines a data access destination based on the importance level of the data to be accessed and on the terminal processing level that has been determined, and accesses the determined access destination.

10. The portable communication terminal according to claim 9 , wherein when the connection state prediction judging section predicts that the communication state will be improved, the terminal processing level determining section decrements the terminal processing level.

11. The portable communication terminal according to claim 9 , further comprising a data hold managing section that, when the terminal processing level is changed and there is update on data whose importance level is changed to an importance level which inhibits the data from being held at the changed terminal processing level, reflects an update content on corresponding data stored in the server, and then deletes the data whose importance level is changed to an importance level which inhibits the data from being held from the terminal data storage section.

12. The portable communication terminal according to claim 9 , wherein when the connection state prediction judging section predicts that the communication state will be deteriorated, the terminal processing level determining section increments the terminal processing level.

13. The portable communication terminal according to claim 9 , wherein when the terminal processing level is changed by a change in the prediction result on the communication state, data whose importance level is changed to an importance level which permits the data to be held at the changed terminal processing level is read from the server and copied into the terminal data storage section.

14. The portable communication terminal according to claim 9 , wherein the connection state prediction judging section has a unit of acquiring positional information and movement information of the portable communication terminal, and

uses the acquired information in predicting a future change in the communication state.

15. The portable communication terminal according to claim 9 , wherein upon occurrence of a data read request,

the data access managing section determines whether or not the terminal processing level at that time is equal to or higher than an importance level given to data to be read out which is indicated by the received read request,

reads the data to be read from the portable communication terminal when it is determined that the determined terminal processing level is equal to or higher than the importance level, and

reads the data to be read from the server when it is determined that the determined terminal processing level is less than the importance level.

16. The portable communication terminal according to claim 9 , wherein upon occurrence of a data write request,

the data access managing section determines whether or not the terminal processing level at that time is equal to or higher than an importance level given to data to be written which is indicated by the received write request,

writes the data to be written into the portable communication terminal when it is determined that the determined terminal processing level is equal to or higher than the importance level, and

writes the data to be written into the server when it is determined that the determined terminal processing level is less than the importance level.