Fault-tolerant distributed system for collaborative computing

• US 20030167303A1
• Filed: 12/29/2000
• Published: 09/04/2003
• Est. Priority Date: 12/29/2000
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: WebEx Communications Incorporated (Cisco Systems, Inc.)
• Inventors: Zhu, Min, Shen, Jian, Yan, Shi
• Granted Patent: US 7,069,298 B2
• Time in Patent Office: Days
• US Class Current: 709/204
• CPC Class Codes: H04L 12/1827 Network arrangements for conference optimisation or adaptation
• CPC Class Codes: H04L 12/1868 Measures taken after transmission, e.g. acknowledgments
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A fault-tolerant distributed collaborative computer system is provided that comprises a plurality of server computers interconnected via a high-speed link. By replicating the conference information on more than one server computer, the single point of failure limitation is eliminated. In fact, if a server hosting or participating in a conference malfunctions, the failure is detected by other server computers and the client computer is able to reconnect to the conference through a new server computer. In addition, the state of processes executed by the server computers is periodically replicated, so that when failure of a process is detected a new processes can be spawned and the replicated state information loaded onto the new process, allowing the on-line conference to continue.

Claims

1. A computer system for fault-tolerant distributed collaborative computing, the system comprising:

a plurality of server computers connected to a plurality of client computers via a global-area computer network;

a high-speed direct connection link connecting the plurality of server computers; and

a computer program executable by the server computers, wherein the computer program comprises computer instructions for;

conducting an on-line conference among an arbitrary number of the client computers connected to an arbitrary number of the server computers via the global-area network and the high-speed direct connection link;

detecting a failure of one of the server computers handling the on-line conference;

disconnecting the failed server computer from the on-line conference;

connecting another of the server computers to the conference; and

resuming the on-line conference.

2. The computer system of claim 1, wherein the computer program further comprises computer instructions for:

periodically replicating state information among processes executed by the server computers to conduct the on-line conference;

detecting a failure of one of the process;

spawning a new process on the server computers; and

loading the replicated state information on the new process.

3. The computer system of claim 2, wherein the processes whose state is replicated maintain information about the on-line conference.

4. The computer system of claim 2, wherein the processes whose state is replicated handle communications between one of the client computers and one of the server computers.

5. The computer system of claim 2, wherein the processes whose state is replicated control access to a document shared among participants of the on-line conference.

6. The computer system of claim 2, wherein the processes whose state is replicated control execution of an application shared among participants of the on-line conference.

7. A method of operating a distributed collaborative computing system comprising a plurality of server computers, the method comprising:

conducting an on-line conference among an arbitrary number of the client computers connected to an arbitrary number of the server computers via the global-area network and the high-speed direct connection link;

detecting a failure of one of the server computers handling the on-line conference;

disconnecting the failed server computer from the on-line conference;

connecting another of the server computers to the conference; and

resuming the on-line conference.

8. The method of claim 7, further comprising:

periodically replicating state information among processes executed by the server computers to conduct the on-line conference;

detecting a failure of one of the process;

spawning a new process on the server computers; and

loading the replicated state information on the new process.

9. The method of claim 8, wherein the processes whose state is replicated maintain information about the on-line conference.

10. The method of claim 8, wherein the processes whose state is replicated handle communications between one of the client computers and one of the server computers.

11. The method of claim 8, wherein the processes whose state is replicated control access to a document shared among participants of the on-line conference.

12. The method of claim 8, wherein the processes whose state is replicated control execution of an application shared among participants of the on-line conference.

13. A computer-readable storage medium storing a computer program executable by a plurality of server computers, the computer program comprising computer instructions for:

conducting an on-line conference among an arbitrary number of the client computers connected to an arbitrary number of the server computers via the global-area network and the high-speed direct connection link;

detecting a failure of one of the server computers handling the on-line conference;

disconnecting the failed server computer from the on-line conference;

connecting another of the server computers to the conference; and

resuming the on-line conference.

14. The computer-readable storage medium of claim 13, wherein the computer program further comprises computer instructions for:

periodically replicating state information among processes executed by the server computers to conduct the on-line conference;

detecting a failure of one of the process;

spawning a new process on the server computers; and

loading the replicated state information on the new process.

15. The computer-readable storage medium of claim 14, wherein the processes whose state is replicated maintain information about the on-line conference.

16. The computer-readable storage medium of claim 14, wherein the processes whose state is replicated handle communications between one of the client computers and one of the server computers.

17. The computer-readable storage medium of claim 14, wherein the processes whose state is replicated control access to a document shared among participants of the on-line conference.

18. The computer-readable storage medium of claim 14, wherein the processes whose state is replicated control execution of an application shared among participants of the on-line conference.