Method and apparatus for workgroup information replication

• US 6,182,117 B1
• Filed: 06/12/1997
• Issued: 01/30/2001
• Est. Priority Date: 05/31/1995
• Status: Expired due to Term

• Current Assignee: Meta Platforms, Inc. (f/k/a Facebook, Inc.)
• Original Assignee: Netscape Communications Corporation (Apollo Global Management, Inc.)
• Inventors: Winner, Jeffrey, Christie, David
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Previl, Daniel
• Application Number:
  US08/873,569
• Time in Patent Office: 1,328 Days
• Field of Search: 395/200.01, 395/200.02, 395/200.08, 395/200.18, 395/600, 395/650, 395/700, 395/182.9, 364/514.006, 709/204, 709/205, 709/227, 714/4, 714/41, 714/56, 714/57
• US Class Current: 709/205
• CPC Class Codes: G06Q 10/10 Office automation; Time management
• CPC Class Codes: G06Q 10/107 Computer-aided management of electronic mailing [e-mailing]

Abstract

The present invention provides the ability to use an existing store-and-forward messaging network such as an electronic mail system to replicate data between computer sites. The replication provided by the present invention can be used with software applications, such as workgroup applications, to replicate data located on multiple sites. Workgroup replication data is sent to other sites via electronic mail (“e-mail”) messages. The present invention provides reliability features to handle errors in electronic mail transmissions. For example, the present invention provides the ability to reassemble objects at a replication site such that an object and all of its dependencies exist prior to the object'"'"'s use at the site. Messages referred to as “ACK” messages are used to communicate a site'"'"'s state and to provide other control information. Each site maintains latency information to determine transmission failures.

Claims

1. A method of replicating information between a first and second site comprising:

maintaining, at said first site, an index of objects known to said first site;

maintaining at said first site state information for said first site, said state information comprising information about one or more of said objects;

transmitting said first site'"'"'s state information to said second site;

updating said second site'"'"'s state using said first site'"'"'s state information.

2. The method of claim 1 further comprising:

said second site determining from said first site'"'"'s state information whether an object of said second site is to be sent to said first site; and

transmitting by said second site a message containing said second site'"'"'s object, if said second site determines that said second site'"'"'s object is to be sent to said first site.

3. The method of claim 2 further comprising:

said first site determining whether dependencies exist for said second site'"'"'s object; and

resolving said dependencies when said dependencies exist for said second site object.

4. The method of claim 2 further comprising:

said first site updating said index of objects to include said second site object.

5. A method of replicating information comprising:

maintaining, at a first site, a list of objects and state information about one or more of said objects;

transmitting said state information to a second site via at least one messaging system;

said second site determining from said state information whether an object is to be sent to said first site.

6. The method of claim 5 further comprising:

said first site determining whether dependencies exist for said second site'"'"'s object.

7. The method of claim 6 further comprising:

resolving said dependencies when said dependencies exist for said second site object.

8. The method of claim 5 further comprising:

said first site updating said list of objects to include said second site object.

9. The method of claim 5 further comprising:

updating said second site'"'"'s state using said first site'"'"'s state information.

10. The method of claim 5 further comprising:

transmitting said object to said first site via said at least one messaging system, if said second site determines that said object is to be sent to said first site.

11. The method of claim 5 wherein said messaging system comprising at least one store and forward messaging system.

12. The method of claim 11 wherein said at least one store and forward messaging system comprising at least one electronic mail system.

13. A system comprising:

a first replicator associated with a first forum, said first replicator configured to manage a repository comprising a list of objects and state information of one or more of said objects;

at least one messaging system coupled to said first replicator;

a second replicator coupled to said at least one messaging system, said second replicator configured to receive messages from said first replicator via said messaging system, said second replicator further configured to manage a repository associated with a second forum.

14. The system of claim 13 wherein said first and second replicator further configured to update objects in said first and second forums, respectively.

15. The system of claim 13 wherein one of said messages comprises state information.

16. The system of claim 13 wherein one of said messages comprises an object.

17. The system of claim 13 wherein said at least one messaging system further comprising at least one store and forward messaging system.

18. The system of claim 14 wherein said at least one messaging system further comprising at least one electronic mail system.

19. The system of claim 13 wherein each of said first and second replicators further comprising:

an inbound process configured to receive objects from another forum;

an outbound process configured to identify the objects to be sent to said another forum.

20. The system of claim 19 wherein said inbound process further comprising:

a discovery phase configured to process replication events associated with said objects;

a reassembly phase configured to resolve dependencies associated with one of said objects.

21. The system of claim 20 wherein said discovery phase is further configured to discard duplicate replication events, process any dependencies associated with said objects, and identify a latest version of said objects.

22. The system of claim 20 wherein a dependent object depends on another object, said reassembly phase is further configured to mark a dependency associated with said dependent object as satisfied if said another object is obtainable or already obtained.

23. The system of claim 22 wherein said dependent object is available for use if said dependency is satisfied.

24. The system of claim 20 wherein a replication event comprises an object modification occurring in either of said first or second forums.

25. A computer program product comprising:

a computer usable medium having computer readable program code configured to replication information embodied therein comprising;

computer readable program code configured to cause a computer to maintain, in a first forum, a list of objects and state information about one or more of said objects;

computer readable program code configured to cause a computer to transmit said state information to a second forum via at least one messaging system;

computer readable program code configured to cause a computer to determine, in said second forum using said state information, whether an object is to be sent to said first forum.

26. The computer program product of claim 25 further comprising:

computer readable program code configured to cause a computer to determine, in said first forum, whether dependencies exist for said second forum'"'"'s object.

27. The computer program product of claim 26 further comprising:

computer readable program code configured to cause a computer to resolve said dependencies when said dependencies exist for said second forum object.

28. The computer program product of claim 25 further comprising:

computer readable program code configured to cause a computer to update, in said first forum, said list of objects to include said second forum object.

29. The computer program product of claim 25 further comprising:

computer readable program code configured to cause a computer to update said second forum'"'"'s state using said first forum'"'"'s state information.

30. The computer program product of claim 25 further comprising:

computer readable program code configured to cause a computer to transmit said object to said first forum via said at least one messaging system, if said second forum determines that said object is to be sent to said first forum.

31. The computer program product of claim 25 wherein said messaging system comprising at least one store and forward messaging system.

32. The computer program product of claim 31 wherein said at least one store and forward messaging system comprising at least one electronic mail system.

33. A method of replicating information between a first and second site comprising:

maintaining, at said first site, an index of objects known to said first site;

maintaining at said first site state information for said first site, said state information comprising information about one or more of said objects;

transmitting said first site'"'"'s state information to said second site;

updating said second site'"'"'s state using said first site'"'"'s state information, said second site determining from said first site'"'"'s state information whether an object of said second site is to be sent to said first site;

transmitting by said second site a message containing said second site'"'"'s object, if said second site determines that said second site'"'"'s object is to be sent to said first site, said first site determining whether dependencies exist for said second site'"'"'s object;

resolving said dependencies when said dependencies exist for said second site object;

said first site updating said index of object to include said second site object.