Method and apparatus for split download

• US 7,058,722 B2
• Filed: 10/29/2001
• Issued: 06/06/2006
• Est. Priority Date: 10/30/2000
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Matsugatani, Kazuoki, Ikami, Yukihito
• Primary Examiner(s): Dharia, Rupal
• Assistant Examiner(s): BAYARD, DJENANE M
• Application Number:
  US10/000,041
• Publication Number:
  US 20020059400A1
• Time in Patent Office: 1,681 Days
• Field of Search: 709/219, 709/203, 709/213, 709/231, 709/218
• US Class Current: 709/231
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor

Abstract

A download method forms a download user network with a plurality of user terminals which are going to download the same data. The delivery server divides the data into data portions, and assigns the data portions to the respective user terminals belonging to the download user network. Then each of the user terminals downloads the assigned data portion from the delivery server. Thereafter the downloaded data portions are mutually transmitted among the user terminals within the download user network so that each of the user terminals can obtain all the data portions which constitute the data. Each of the user terminals combines the obtained data portions into the original data. Thus the data is efficiently downloaded to the plurality of user terminals.

Claims

1. A download method for downloading data from a delivery server to a plurality of user terminals, comprising the steps of:

forming a download user network with the plurality of user terminals to download said data to the plurality of user terminals;

said delivery server dividing said data into a plurality of data portions, each of said plurality of data portions being assigned to a respective user terminal;

downloading each of said assigned data portions from said delivery server to each of said respective user terminals; and

transmitting each of said plurality of data portions among said plurality of user terminals so that each of said plurality of user terminals receive said data by receiving each of said plurality of data portions.

2. A download method as in claim 1,

wherein said dividing step is performed according to a number of said plurality of user terminals.

3. A download method as in claim 2, said forming step further comprising the steps of:

selecting one of said plurality of user terminals as a representative user terminal; and

said representative user terminal transmitting information from which the number of said plurality of user terminals is obtained to said delivery server.

4. A download method as in claim 3, said forming step further comprising the steps of:

said representative user terminal gathering communication environment information on each of said plurality of said user terminals; and

said representative user terminal transmitting said gathered communication environment information to said delivery server,

wherein said dividing step is performed according to said communication environment information.

5. A download method as in claim 3,

wherein said representative user terminal notifies said delivery server of an addition of a new user terminal to said download user network if said new user terminal joins said download network between completion of said forming step and beginning of said mutual transmitting step,

wherein said delivery server redivides said data into a plurality of new data portions in response to the addition of said new user terminal so that said plurality of new data portions are reassigned to said new user terminal and said plurality of said user terminals, respectively, and

wherein said downloading step is achieved by downloading said reassigned data portions from said delivery server to said new user terminal and said plurality of user terminals, respectively.

6. A download method as in claim 3,

wherein a new user terminal obtains said plurality of data portions which constitute said data from said plurality of user terminals during said mutual transmitting step if said new user terminal joins said download user network between completion of said forming step and beginning of said mutual transmitting step.

7. A download method as in claim 3,

wherein if one of said plurality of user terminals is disconnected from said delivery server between completion of said forming step and beginning of said mutual transmitting step, said delivery server redivides said data into a plurality of new data portions so that said plurality of new data portions are reassigned to said plurality of user terminals except said disconnected user terminal, and

wherein said downloading step is achieved by downloading said plurality of reassigned data portions from said delivery server to said plurality of user terminals except said disconnected user terminal, respectively.

8. A download method as in claim 3,

wherein said representative user terminals gives said plurality of user terminals an instruction to start the mutual transmitting step when said representative user terminal determines that said downloading step is completed in all of said plurality of user terminals, and

wherein said mutual transmitting step is started simultaneously in all of said plurality of user terminals in response to said instruction.

9. A download method as in claim 4,

wherein said dividing step is performed so that said data portions overlap each other according to said communication environment information.

10. A download method as in claim 1,

wherein said mutual transmitting step is started severally in each of said plurality of user terminals when said downloading step is completed in the user terminal.

11. A download method as in claim 1, said dividing step further comprising the steps of:

generating a split download map including information on correspondence between said plurality of user terminals and said data portions assigned thereto; and

attaching said split download map to each of said data portions,

wherein said split download map is downloaded with each of said data portions to each of said plurality of user terminals in said downloading step.

12. A user terminal for downloading data from a delivery server comprising:

means for forming a download user network with at least one other user terminal to download said data to said user terminal and to said other user terminal;

means for downloading a first data portion of said data from a delivery server to said user terminal and a second data portion of said data to said other user terminal;

means for transmitting said first data portion to said other user terminal and receiving said second data portion of said data from said other user terminal; and

means for combining said first and second data portions into said data at said user terminal and at said other user terminal.

13. A download system for downloading same data to a plurality of user terminals comprising:

a plurality of user terminals capable of forming a local area network; and

a delivery server capable of communicating with said plurality of user terminals,

wherein said data is divided into a plurality of data fragments and each of said plurality of data fragments are assigned to a respective user terminal; and

wherein each of said plurality of user terminals downloads its respective assigned data fragment from said delivery server, and exchange said downloaded data fragments with one another via said local area network so that each of said plurality of user terminals obtains each of the plurality of data fragments of said data.

14. A download system as in claim 13,

wherein said delivery server communicates with said plurality of user terminals via a wide area network.