Networked transmission system and method for stream data

• US 8,176,192 B2
• Filed: 05/13/2008
• Issued: 05/08/2012
• Est. Priority Date: 12/31/2007
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Miao, Yu-Ben, Yu, Yun-Shuai, Lin, Chung-Shiang, Shieh, Ce-Kuan
• Primary Examiner(s): Lin, Kenny
• Assistant Examiner(s): Ali, Farhad
• Application Number:
  US12/119,503
• Publication Number:
  US 20090172179A1
• Time in Patent Office: 1,456 Days
• Field of Search: 709/231, 709/201, 709/249, 725/118, 370/230
• US Class Current: 709/231
• CPC Class Codes: H04L 65/762 at the source reformatting of additional data in video distribution servers H04N21/2355
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04L 67/1046 Joining mechanisms
• CPC Class Codes: H04L 67/1051 Group master selection mechanisms

Abstract

Disclosed is a networked transmission system and method for stream data. The system comprises a network, a streaming server and an ordered series of a first up to n-th cooperative-sharing groups. There is a cooperative relationship among all users'"'"' terminals in a cooperative-sharing group. The streaming server provides a plurality of programs with stream data, each program being divided into one or more audio/video clips by a time-slot unit. The streaming server transmits the one or more audio/video clips to the leader node of the first cooperative-sharing groups. The leader node of each cooperative-sharing group transmits the currently received audio/video clip to the users'"'"' terminals within the same cooperative-sharing group, and passes the received audio/video clip to the leader node of the next cooperative-sharing group after one time slot.

Claims

1. A networked transmission system for stream data, comprising:

a network;

a streaming server, for providing a plurality of stream data programs, with each stream data program being divided into a plurality of stream data segments according to a predefined time length;

an ordered sequence of n cooperative-sharing groups for receiving a specific stream data program, numbered from 1^st to n-th, with n being an integer, each group of said n cooperative-sharing groups being formed by a plurality of user terminals requesting said streaming server for said specific stream data program with a user terminal of said plurality of user terminals being selected by said streaming server as a leader node of the cooperative-sharing group, wherein the user terminals of the k-th cooperative-sharing group request said streaming server for said specific stream data program in a time period of (k−

1) to k times said predefined time length later than first request of said specific stream data program by the user terminals of the 1^st cooperative-sharing group, with 1≦

k≦

n;

where said streaming server transmits said plurality of stream data segments, one by one, through said network to said leader node of the first cooperative-sharing group, said leader node of each cooperative-sharing group multicasting each currently received stream data segment peer-to-peer to all the user terminals within the same cooperative-sharing group, and relaying said currently received stream data segment to the leader node of a next cooperative-sharing group after said predefined time length.

2. The system as claimed in claim 1, wherein each operation that a user terminal executes is one of operations including joining said system, changing playing progress, and departing from said system.

3. The system as claimed in claim 2, wherein when a user terminal is joining said system, said streaming server responds to said user terminal with a network address of the leader node of the cooperative-sharing group which said user terminal is joining.

4. The system as claimed in claim 2, wherein when a user terminal changes playing progress, said streaming server receives a changing request from said user terminal and conducts a search and responses to said user terminal for switching to another cooperative-sharing group.

5. The system as claimed in claim 2, wherein when a user terminal which is a leader node of one of said n cooperative-sharing groups departs from said system, said streaming server selects another user terminal within the original cooperative-sharing group of the departing user terminal as a new leader node of the original cooperative-sharing group.

6. The system as claimed in claim 2, wherein when a user terminal joins said system, changes playing progress, or departs from and re-joins said system, if said user terminal joins an empty cooperative-sharing group, said streaming server directly serves said user terminal and said user terminal becomes the leader node of said empty cooperative-sharing group.

7. The system as claimed in claim 1, wherein said streaming server has a memory space for recording a network address of each leader node of each of said n cooperative-sharing groups.

8. The system as claimed in claim 1, wherein the speed of said streaming server transmitting stream data segment is greater than or equal to the speed of program playing.

9. The system as claimed in claim 1, wherein said streaming server has a buffer for storing the original stream data of said plurality of stream data programs.

10. The system as claimed in claim 1, wherein the leader node of each of said n cooperative-sharing groups has a buffer for storing the stream data segments of two periods of said time length, and each user terminal of non-leader nodes has a buffer for storing the stream data segment of a period of said time length.

11. The system as claimed in claim 1, wherein said streaming server takes said time length as a unit to define said ordered sequence of said n cooperative-sharing groups, numbered 1^st to n-th.

12. A networked transmission method for stream data, applicable to a networked transmission system, said method comprising:

defining a time length TS, and taking said time length as a unit to divide each of a plurality of stream data programs provided by a streaming server into a plurality of stream data segments;

taking said time length as a unit to define an ordered sequence of n cooperative-sharing groups for receiving a specific stream data program, numbered 1^st to n-th, each cooperative-sharing group being formed by a plurality of user terminals requesting said streaming server for said specific stream data program;

using said streaming server to select a user terminal from each group of said n cooperative-sharing groups as a leader node of the cooperative-sharing group;

during each period of said time length, transmitting a stream data segment from said streaming server to the leader node of the first cooperative-sharing group; and

using the leader node of each group of said n cooperative-sharing groups to multicast each currently received stream data segment peer-to-peer to other user terminals of the same cooperative-sharing group, and after a period of said time length, to relay said currently received stream data segment to the leader node of a next cooperative-sharing group;

wherein the user terminals of the k-th cooperative-sharing group request said streaming server for said specific stream data program in a time period of (k−

1) to k times TS later than first request of said specific stream data program by the user terminals of the 1^st cooperative-sharing group, with 1≦

k≦

n.

13. The method as claimed in claim 12, wherein said method further includes operations of a user terminal joining said system, a user terminal changing playing progress, and a user terminal departing from said system, or any combinations of the above.

14. The method as claimed in claim 13, wherein the operation of a user terminal joining said system further includes:

defining an initial time of an earliest user terminal joining to view a stream data program as T_ini; and

assigning said user terminal and subsequent user terminals joining said system to the [(T−

T_ini)/TS]+1 cooperative-sharing group, where [ ] is a Gaussian integer, and T is the joining time at which each said subsequent user terminal joins to view said stream data program.

15. The method as claimed in claim 13, wherein the operation of a user terminal changing playing progress further includes:

said user terminal transmitting a new time T_new of playing progress for an interesting data stream segment to said streaming server through an inquiry message;

said streaming server computing which cooperative-sharing group is currently multicasting the stream data segment which said T_new belongs to, and returning a network address of the leader node of the multicasting cooperative-sharing group to said user terminal;

said user terminal informing a parent node in the original cooperative-sharing group of said user terminal of switching to another cooperative-sharing group; and

said user terminal sending a join message to the leader node of the multicasting cooperative-sharing group to be switched to.

16. The method as claimed in claim 15, wherein when said user terminal is connected to at least a child node, said user terminal informs said at least a child node of said switching, and asks each of the child nodes to search for another user terminal in the original cooperative-sharing group as the parent node.

17. The method as claimed in claim 15, wherein when said user terminal is a leader node of the original cooperative-sharing group, said user terminal requests said streaming server to select another leader node for the original cooperative-sharing group.

18. The method as claimed in claim 13, wherein when a user terminal changes playing progress and switches to an empty cooperative-sharing group, said streaming server directly serves said user terminal and selects said user terminal as the leader node of said empty cooperative-sharing group.

19. The method as claimed in claim 13, wherein the operation of a user terminal departing from said system further includes:

checking whether the departing user terminal is a leader node;

if so, selecting a new leader node and informing all child nodes of the departing user terminal to search for another parent node within the original cooperative-sharing group of the departing user terminal; and

otherwise, informing a parent node and all child nodes of the departing user terminal that the user terminal is departing.

20. The method as claimed in claim 19, wherein when the departing user terminal is not a leader node, the method further includes the steps of said parent node stopping serving the departing user terminal and said child nodes searching for other parent nodes.