System for determination of the equivalence of two objects without compromising then done by a third object nominated by one and accetped by the other

• US 5,301,316 A
• Filed: 10/30/1991
• Issued: 04/05/1994
• Est. Priority Date: 10/30/1991
• Status: Expired due to Term

• Current Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Chapin, John, Hamilton, Graham, Powell, Michael L.
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): AMSBURY, WAYNE P
• Application Number:
  US07/787,320
• Time in Patent Office: 888 Days
• Field of Search: 395/600, 395/425, 380/4
• US Class Current: 1/1
• CPC Class Codes: G06F 9/465 Distributed object oriented systems remote method invocation [RMI] G06F9/548
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users

Abstract

In an object oriented distributed system based on the client-server model, the client domains, the server domains and the objects are implemented in an improved manner such that a client domain determines whether a first and a second object implemented by a first and a second server domain are equivalent by requesting the first object to nominate a third object to make the determination, the second object to concur to the nomination, and the nominated third object to make the determination, thereby allowing the determination to be made without comprising the first and second objects and the first and second server domains'"'"' security.

Claims

1. In a network of computer systems comprising at least one central processing unit (CPU) executing a plurality of client and server processes wherein said processes and data manipulated by said processes are implemented as objects, a computer-implemented method for a client process to securely determine if a first and a second objects supported by a first and a second server processes respectively are equivalent objects with respect to one of the attributes such as contents, functionality, location and size, without compromising said first and second objects and said first and second server processes'"'"' security, said method comprising the steps of:

a) requesting said first object to nominate a third object to perform said determination for said client process by said client process;

b) replying to said client process with said nomination by said first object;

c) requesting said second object to concur to said nomination by said client process;

d) replying to said client process one of concurrence and nonconcurrence by said second object;

e) if said reply by said second object is a nonconcurrence, determining said first and second objects to be non-equivalent objects by said client process;

f) if said reply by said second object is a concurrence, requesting said third object to perform said determination for said client process by said client process; and

g) if said reply by said second object is a concurrence, performing said determination for said client process, and returning a determination result to said client process by said third object, said determination result indicating whether said first and second objects are equivalent objects.

2. The method as set forth in claim 1, wherein,

said first, second and third objects are referenced by a first, a second and a third object handle respectively;

said third object is nominated by returning said third object handle to said client process;

said second object'"'"'s concurrence is requested by said client process by forwarding said returned third object handle to said second object; and

said third object is requested to perform said determination for said client process by said client process by forwarding said first and second object handles to said third object.

3. The method as set forth in claim 1, wherein,

said third object is nominated by said first server process, said first server process being notified of said request for nomination;

said one of concurrence and nonconcurrence is replied by said second server process, said second server process being notified of said request for concurrence.

4. The method as set forth in claim 3, wherein,

said first and second server processes are the same server process;

said first, second and third objects are implemented by said same server process;

said same server process checks to confirm said first, second and third objects are implemented by said same server process, said third object being checked before said same server process concurs with said third object'"'"'s nomination, said first and second objects being checked before said third object performs said determination for said client process, and returns said determination result to said client process.

5. The method as set forth in claim 4, wherein,

said first, second and third objects are referenced by a first, a second and a third object handle respectively;

said third object is nominated by said same server process by returning said third object handle to said client process;

said second object'"'"'s concurrence is requested by said client process by forwarding said returned third object handle to said second object;

said third object is checked by said same server process to confirm said third object is implemented by said same server process using said third object handle;

said third object is requested to perform said determination for said client process by said client process by forwarding said first and second object handles to said third object; and

said first and second objects are checked by said same server process to confirm said first and second objects are implemented by said same server process using said first and second object handles.

6. The method as set forth in claim 3, wherein,

said first and second server processes are cooperative server processes, each having implemented at least one object that is equivalent to an object implemented by the other server process;

said first and third objects are implemented by said first server process, and said second object is implemented by said second server process, said first, second, and third objects being capable of identifying one of said first and second server processes as their implementing server processes respectively;

said second server process in concert with said first server process checks to confirm said third object is implemented by said first server process, said third object being checked before said second server process concurs to said third object'"'"'s nomination, said first server process being identified to said second server process as said third object'"'"'s implementing server process by said third object; and

said first server process in concert with said second server process checks to confirm said first and second objects are implemented by said first and second processes respectively, said first and second objects being checked before said third object performs said determination for said client process, and returns said determination result to said client process, said second server process being identified to said first server process as said second object'"'"'s implementing server process by said second object.

7. The method as set forth in claim 6, wherein,

said first, second and third objects are referenced by a first, a second and a third object handle respectively;

said third object is nominated by said first server process by returning said third object handle to said client process;

said second server process'"'"'s concurrence is requested by said client process by forwarding said returned third object handle to said second server process;

said third object is checked by said second server process in concert with said first server process to confirm said third object is implemented by said first server process using said third object handle, said third object handle being forwarded to said first server process by said second server process;

said third object is requested to perform said determination for said client process by said client process by forwarding said first and second object handles to said third object;

said first and second objects are checked by said first server process in concert with said second server process to confirm said first and second objects are implemented by said first and second server processes using said first and second object handles respectively, said second object handle being forwarded to said second server process by said first server process; and

said determination is made by said third object using said first and second object handles, and object information regarding said second object, said object information being provided to said third object by said second server process.

8. The method as set forth in claim 6, wherein, said first and second servers communicate with each other in a secured manner whereby security of said first, second and third objects and said first and second servers is maintained.

9. In a network of computer systems comprising at least one central processing unit (CPU) executing a plurality of client and server processes wherein said processes and data manipulated by said processes are implemented as objects, and apparatus for a client process to securely determine if a first and a second objects supported by a first and a second server processes respectively are equivalent objects with respect to one of the attributes such as contents, functionality, location and size, without compromising said first and second objects and said first and second server processes'"'"' security, comprising:

a) client means comprising a client CPU for executing said client process, facilitating said client process in requesting said first object to nominate a third object to perform said determination for said client process, and subsequently requesting said second object to concur to said nomination;

b) first server means coupled to said first client means comprising a first server CPU for executing said first server process, manipulating said first object, and facilitating replying to said client process with said nomination by said first object;

c) second server means coupled to said first client means comprising a second server CPU for executing said second server process, manipulating said second object, and facilitating replying to said client process one of concurrence and nonconcurrence by said second object;

wherein if said reply to said client process by said second object is a nonconcurrence, said client process considers said first and second objects as non-equivalent objects; and

if said reply to said client process by said second object is a concurrence, said client means is also for facilitating said client process in requesting said third object to perform said determination for said client process, and said first server means is also for manipulating said third object and facilitating said third object in performing said determination for said client process, and returning a determination result to said client process, said determination result indicating whether said first and second objects are equivalent objects.

10. The apparatus as set forth in claim 9, wherein,

said first, second and third objects are referenced by a first, a second and a third object handle respectively;

said client means facilitates subsequently requesting said second object to concur to said nomination by facilitating forwarding of said returned third object handle to said second object, and facilitating requesting said third object to perform said determination for said client process by facilitating forwarding of said first and second object handles to said third object; and

said first server means facilitates replying to said client process with said nomination by facilitating returning of said third object handle to said client process.

11. The apparatus as set forth in claim 9, wherein,

said third object is nominated by said first server process, said first server process being notified of said request for nomination;

said one of concurrence and nonconcurrence is replied by said second server process, said second server process being notified of said request for concurrence.

12. The apparatus as set forth in claim 11, wherein,

said first and second server means are the same server means;

said first and second server processes are the same server process;

said first, second and third objects are implemented by said same server process;

said same server means is also for facilitating said same server process in checking to confirm said first, second and third objects are implemented by said same server process, said third object being checked before said same server process concurs with said third object'"'"'s nomination, said first and second objects being checked before said third object performs said determination for said client process, and returns said determination result to said client process.

13. The apparatus as set forth in claim 12, wherein,

said first, second and third objects are referenced by a first, a second and a third object handle respectively;

said client means facilitates said client process in requesting said second object'"'"'s concurrence by facilitating forwarding of said returned third object handle to said second object, and facilitates said client process in requesting said third object to perform said determination for said client process by facilitating forwarding of said first and second object handles to said third object; and

said same server means facilitates said same server process in replying to said client process with nomination by facilitating returning of said third object handle to said client process, facilitates said same server process in checking said third object to confirm said third object is implemented by said same server process using said third object handle, and facilitates said same server process in checking said first and second objects to confirm said first and second objects are implemented by said same server process using said first and second object handles.

14. The apparatus as set forth in claim 11, wherein,

said first and second server processes are cooperative server processes, each having implemented at least one object that is equivalent to an object implemented by the other server process;

said first and third objects are implemented by said first server process, and said second object is implemented by said second server process, said first, second, and third objects being capable of identifying one of said first and second server processes as their implementing server processes respectively;

said first and second server means are also coupled with each other;

said first server means is also for facilitating said first server process in concert with said second server process in checking to confirm said first and second objects are implemented by said first and second server processes respectively, said first and second objects being checked before said third object performs said determination for said client process, and returns said determination result to said client process, said second server process being identified to said first server process as said second object'"'"'s implementing server process by said second object; and

said second server means is also for facilitating said second server process in concert with said first server process in checking to confirm said third object is implemented by said first server process, said third object being checked before said second server process concurs to said third object'"'"'s nomination, said first server process being identified to said second server process as said third object'"'"'s implementing server process by said third object.

15. The apparatus as set forth in claim 14, wherein,

said first, second and third objects are referenced by a first, a second and a third object handle respectively;

said client means facilitates said client process in requesting said second server process'"'"'s concurrence by facilitating forwarding of said returned third object handle to said second server, facilitates said client process in requesting said third object to perform said determination for said client process by facilitating forwarding of said first and second object handles to said third object;

said first server means facilitates said first server process in replying to said client process with said third object'"'"'s nomination by facilitating returning of said third object handle to said client process, facilitates said second server process in concert with said first server process in checking to confirm said third object is implemented by said first server process by facilitating using of said third object handle, facilitates said first server process in concert with said second server process in checking said first and second objects to confirm said first and second objects are implemented by said first and second server processes by facilitating using of said first object handle, and forwarding of said second object handle to said second server process respectively, and facilitates said third object in making said determination by facilitating using of said first and second object handles, and object information regarding said second object, said object information being provided to said third object by said second server process; and

said second server means facilitates said second server process in concert with said first server process in checking to confirm said third object is implemented by said first server process by facilitating forwarding of said third object handle to said first server process, facilitates said first server process in concert with said second server process in checking to confirm said second object is implemented by said second server process by facilitating using of said second object handle, and facilitates said third object in making said determination by facilitating providing of said object information regarding said second object to said third object.

16. The apparatus as set forth in claim 14, wherein, said first and second server means facilitates said first and second servers to communicate with each other in a secured manner.

17. The apparatus as set forth in claim 9, wherein, at least two of said client CPU, said first server CPU, and said second server CPU, are the same CPU.