Wireless communication method permitting efficient use of system resources

• US 6,363,412 B1
• Filed: 11/20/1998
• Issued: 03/26/2002
• Est. Priority Date: 11/21/1997
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Niwa, Yushi, Matsumoto, Hidehiro
• Primary Examiner(s): Maung, Zarni
• Assistant Examiner(s): Barot, Bharat
• Application Number:
  US09/196,539
• Time in Patent Office: 1,222 Days
• Field of Search: 709/200-203, 709/205-206, 709/217-218, 709/227-229, 709/236-239, 455/3--, 455/4.1, 455/412-414, 455/461-466
• US Class Current: 709/203
• CPC Class Codes: H04L 51/58 Message adaptation for wireless communication
• CPC Class Codes: H04W 4/12 Messaging; Mailboxes; Announcements
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 52/0261 managing power supply demand, e.g. depending on battery level
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A communication method for a wireless transmission network having a plurality of terminals and a central server, disclosed in the context of an E-mail system. The source terminal sends only a mail header identifying the message source, the destination and other attribute information to the server. The destination terminal receives the digital data directly from the source terminal when desired after first downloading the mail header from the server. Thus, a data recipient can reduce unnecessary communication cost and storage resources in the server and in the system, can be saved.

Claims

1. A method of digital data transfer between terminals via a server in a wireless transmission network, the digital data being comprised of messages, each message being divided into a header that identifies the source and destination terminals for the message, and a message body, the method comprising the steps of:

generating a message at a data source terminal;

sending only the header of the generated message from the data source terminal to the server;

monitoring by at least a second terminal of only the header at the server to identify whether the monitoring terminal is the intended destination of the message corresponding to the monitored header; and

initiating retrieval of a message body from the source terminal to the monitoring terminal for which the monitoring terminal is the intended destination terminal as indicated by the monitored header.

2. The method of claim 1, wherein the header includes attribute information concerning the associated message.

3. The method of claim 2, wherein the attribute information includes an ID identifying the source terminal, a size of the digital data, a title of the message and an ID identifying the destination terminal.

4. The method of claim 1, further comprising the step of:

transmitting the entire message from the source terminal for storage at the central server if predetermined conditions exist; and

transmitting the message to the destination terminal from the central server on demand.

5. The method of claim 4, further comprising the step of:

storing at the destination terminal reserve information for use in retrieving message bodies intended for the destination terminal before the destination terminal initiates retrieval of the message body from the source terminal, the reserve information being employed in the retrieval of the message.

6. The method of claim 5, further comprising the step of:

receiving by the destination terminal of messages from the source terminals collectively and at every source terminal by sorting the reserve information.

7. The method of claim 5, further comprising the step of:

automatically completing retrieval by the destination terminal of a message from a source terminal within a period of time the reserve information if retrieval of the message from the source terminal has been suspended.

8. The method of claim 1, wherein the predetermined conditions are:

the size of the message is lower than a predetermined value; and

the destination terminal has not monitored headers at the central server for a predetermined period of time.

9. The method of claim 1, further comprising the step of:

supplying the message by the source terminal to the destination terminal in divided form, when the destination terminal receives the message from the source terminal and a size of the message exceeds a predetermined value.

10. The method of claim 1, further comprising the step of:

suspending the retrieval of the message, when the destination terminal receives the message from the source terminal, if a predetermined condition with respect to receiving quality is satisfied.

11. The method of claim 10, wherein the predetermined condition is that the power of a battery of the destination terminal is below a predetermined level.

12. The method of claim 10, wherein the condition is that receiving field intensity at the destination terminal is insufficient for effective reception.

13. The method of claim 10, wherein the condition is that a checksum originally appended to the message and a checksum derived from the received message are not identical a predetermined number of times successively.

14. A wireless digital data transfer system comprising:

a plurality of remote terminals and a server connected by a wireless transmission network, the digital data being comprised of messages,

each remote terminal being operative to generate messages, the messages being comprised of;

a header that identifies the generating terminal as the source of the message, and a destination terminal for the message; and

a message body,

each remote terminal being further operative to;

send only the header of a generated message for storage by the server;

monitor only the headers stored at the server to identify whether the monitoring terminal is the intended destination of messages corresponding to the monitored headers; and

initiate retrieval of a message body from the generating terminal to the monitoring terminal for which the monitoring terminal is the intended the destination terminal as indicated by the monitored header.

15. A computer readable medium which stores a program operable in a wireless communication system comprised of a plurality of remote terminals and a server, the digital data being comprised of messages, each message being divided into a header that identifies the source and destination terminals for the message and a message body, the program comprising the steps of:

generating a message at a data source terminal;

sending only the header of the generated message from the data source terminal for storage by the server;

monitoring by the remote terminal of only headers stored at the central server to identify whether the monitoring terminal is the intended destination of a message corresponding to a monitored header; and

initiating retrieval of the message body from the source terminal to the monitoring terminal for which the monitoring terminal is the intended the destination terminal as indicated by the monitored header.

16. A method of communication in a wireless transmission network including a plurality of terminals and a server, the method being comprised of:

at a first terminal;

generating a message comprised of a header and a content portion,

the header including the first information identifying the first terminal as the source of the message, second information identifying a destination terminal for the message, and third information identifying the content of the message;

storing the message;

transmitting the header of the message to the server; and

transmitting the content portion of the message to the destination terminal in response to a request;

at the server;

storing a transmitted header; and

transmitting a stored header in response to a request, and

at a second terminal;

initiating transmission from the server of a stored header which identifies the second terminal as an intended recipient of a message;

displaying the transmitted header for inspection;

initiating transmission from the first terminal of the content portion of a message corresponding to a displayed header; and

displaying a message transmitted from the first terminal.

17. A method as described in claim 16, in which a header includes a fourth information identifying the length of a message;

and in which the method further comprises, at the server;

initiating transmission of the content portion of a message from a first terminal if the fourth information in a header indicates that the length of a message is below a predetermined value; and

storing a transmitted message content portion along with the header thereof.

18. A method as described in claim 17, further including, at the server:

recording information as to when each of the plurality of terminals last initiated transmission of a header from the server;

initiating transmission of the content portion of a message from the first terminal if the fourth information in a header indicates that the length of a message is below a predetermined value; and

if the time since the terminal identified by the second information in a header last initiated transmission of a header from the server exceeds a predetermined value; and

storing a transmitted message content portion along with the header thereof.

19. A method as described in claim 16, in which transmission of the content portion of a message from a first terminal to the second terminal is suspended if the quality of the transmission channel between the first and second terminals is below a predetermined level.

20. A method as described in claim 16, in which the second terminal is powered by a battery, and wherein transmission of the content portion of a message from a first terminal to the second terminal is suspended if the available batter power at the second terminal is below a predetermined level.

21. A method as described in claim 16, further including:

suspending transmission of the content portion of a message from a first terminal to the second terminal in accordance with predetermined criteria;

identifying as reserved messages those for which transmission to the second terminal has been suspended;

storing information at the second terminal concerning reserved messages

reinitiating transmission of the information content of reserved messages after a suspension thereof in accordance with the stored information.

22. A method as described in claim 21, in which the stored information concerning reserved messages includes the source address thereof, and further including:

sorting the stored information according to source address;

initiating a connection session with each of the first terminals in succession for which source addresses are stored;

reinitiating transmission of the content portion of all messages from the connected first terminal during the connection session.

23. A method as described in claim 16, in which transmission of a header from the server to a particular terminal is initiated only if at least a predetermined number of headers identify the particular terminal as the destination terminal for a message.