Coordinated timing network having servers of different capabilities

• US 8,416,811 B2
• Filed: 04/10/2008
• Issued: 04/09/2013
• Est. Priority Date: 04/10/2008
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Carlson, Scott M., Crabtree, Donald, Dahlen, Dennis J., Dhondy, Noshir R., Hack, Michel H. T., Sevigny, Denise M., Wierbowski, Judith A.
• Primary Examiner(s): Thier, Michael
• Assistant Examiner(s): LOUIS, VINNCELAS
• Application Number:
  US12/100,872
• Publication Number:
  US 20090257456A1
• Time in Patent Office: 1,825 Days
• Field of Search: 370503-520, 370/466, 709/206, 709/248, 709/216, 709/223, 714/4
• US Class Current: 370/503
• CPC Class Codes: H04J 3/0641 Change of the master or reference, e.g. take-over or failure of the master
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols

Abstract

Communication and processing within a timing network that supports servers having different capabilities are facilitated. Individual servers of the network are dynamically updated without disrupting the operational characteristics of the timing network. New capabilities are not utilized between two servers until it is known that both servers are capable of supporting the new features. One server communicates to another server at an acceptable level of the another server.

Claims

1. A computer program product for facilitating communication within a timing network of servers, the computer program product comprising:

a non-transitory storage medium readable by a processor and storing instructions for execution by the processor for performing a method, the method comprising;

operating by one server at one level of timing capability indicated by a version number, the version number indicating one or more supported timing features of the one server;

obtaining by the one server at least one version number supported by another server, the at least one version number supported by the another server indicating one or more versions of timing capability supported by the another server;

determining by the one server, using the obtained at least one version number supported by the another server, a negotiated version number for use in communicating with the another server, the negotiated version number indicating a compatible level of timing capability common to the one server and the another server but different from the one level of timing capability; and

communicating by the one server with the another server at the compatible level of timing capability common to the one server and the another server but different from the one level of timing capability, wherein the one server operates at the one level of timing capability indicated by the version number and communicates with the another server at the compatible level of timing capability indicated by the negotiated version number.

2. The computer program product of claim 1, wherein the timing network comprises an additional server, said additional server operating, independent of communication, at an additional level of timing capability, said additional level of timing capability being different from said one level of timing capability and said compatible level of timing capability, and wherein the one server communicates to the another server at the compatible level of timing capability indicated by the negotiated version number, and the one server communicates with the additional server at a level of timing capability supported by both the one server and the additional server.

3. The computer program product of claim 1, wherein the method further comprises updating a version number of a server of the timing network, wherein the updating is independent of an updating of a version number of one or more other servers of the timing network.

4. The computer program product of claim 3, wherein the updating of the version number is absent disruption of timing synchronization of the timing network.

5. The computer program product of claim 1, wherein a server of the timing network has one or more version numbers associated therewith including a minimum supported version number and a maximum supported version number.

6. The computer program product of claim 5, wherein the minimum supported version number is different from the maximum supported version number, and the one or more version numbers includes at least one version number between the minimum supported version number and the maximum supported version number.

7. The computer program product of claim 5, wherein the minimum supported version number is the same as the maximum supported version number.

8. The computer program product of claim 1, wherein the method further comprises updating a selected version number of a selected server of the timing network, said updating comprising:

notifying, by the selected server, one or more other servers of the timing network that the selected version number is being updated;

determining that the update has taken effect; and

updating at the selected server the selected version number.

9. The computer program product of claim 8, wherein the updating further comprises:

storing, by the one or more other servers, the updated version number for use by the one or more other servers;

modifying, by the selected server and the one or more other servers, an active version number for the selected server and the one or more other servers, respectively;

determining, in response to the modifying for each pair of servers comprising the selected server and one other server of the one or more other servers, whether there is a common version number supported by the selected server and the one other server; and

removing communication paths between the selected server and the one other server, in response to the determining indicating there is no common version number.

10. The computer program product of claim 1, wherein the determining is performed at initialization of a communication path between the one server and the another server.

11. The computer program product of claim 1, wherein the method further comprises performing a version number compatibility check to determine the negotiated version number, which is common to the one server and the another server.

12. The computer program product of claim 1, wherein the one level of timing capability includes aspects related to Server Time Protocol timing, including at least one of recovery, configuration, timing management, formatting of time synchronization messages and time of day clock synchronization.

13. The computer program product of claim 1, wherein the version number comprises a Server Time Protocol version number.

14. A computer-implemented method of facilitating communication within a timing network of servers, said method comprising:

operating by one server at one level of timing capability indicated by a version number, the version number indicating one or more supported timing features of the one server;

obtaining by the one server at least one version number supported by another server, the at least one version number supported by the another server indicating one or more versions of timing capability supported by the another server;

determining by the one server, using the obtained at least one version number supported by the another server, a negotiated version number for use in communicating with the another server, the negotiated version number indicating a compatible level of timing capability common to the one server and the another server but different from the one level of timing capability; and

communicating by the one server with the another server at the compatible level of timing capability common to the one server and the another server but different from the one level of timing capability, wherein the one server operates at the one level of timing capability indicated by the version number and communicates with the another server at the compatible level of timing capability indicated by the compatible version number.

15. The computer-implemented method of claim 14, wherein the timing network comprises an additional server, said additional server operating, independent of communication, at an additional level of timing capability, said additional level of timing capability being different from said one level of timing capability and said compatible level of timing capability, and wherein the one server communicates to the another server at the compatible level of timing capability indicated by the negotiated version number, and the one server communicates with the additional server at a level of timing capability supported by both the one server and the additional server.

16. The computer-implemented method of claim 14, further comprising updating a selected version number of a selected server of the timing network, said updating comprising:

notifying, by the selected server, one or more other servers of the timing network that the selected version number is being updated;

determining that the update has taken effect; and

updating at the selected server the selected version number.

17. The computer-implemented method of claim 16, wherein the updating further comprises:

storing, by the one or more other servers, the updated version number for use by the one or more other servers;

modifying, by the selected server and the one or more other servers, an active version number for the selected server and the one or more other servers, respectively;

determining, in response to the modifying for each pair of servers comprising the selected server and one other server of the one or more other servers, whether there is a common version number supported by the selected server and the one other server; and

removing communication paths between the selected server and the one other server, in response to the determining indicating there is no common version number.

18. A computer system for facilitating communication within a timing network of servers, said computer system comprising:

a memory; and

a processor in communications with the memory, wherein the computer system is configured to perform a method, the method comprising;

operating by one server at one level of timing capability indicated by a version number, the version number indicating one or more supported timing features of the one server;

obtaining by the one server at least one version number supported by another server, the at least one version number supported by the another server indicating one or more versions of timing capability supported by the another server;

determining by the one server, using the obtained at least one version number supported by the another server, a negotiated version number for use in communicating with the another server, the negotiated version number indicating a compatible level of timing capability common to the one server and the another server but different from the one level of timing capability; and

communicating by the one server with the another server at the compatible level of timing capability common to the one server and the another server but different from the one level of timing capability, wherein the one server operates at the one level of timing capability indicated by the version number and communicates with the another server at the compatible level of timing capability indicated by the negotiated version number.

19. The computer system of claim 18, wherein the timing network comprises an additional server, said additional server operating, independent of communication, at an additional level of timing capability, said additional level of timing capability being different from said one level of timing capability and said compatible level of timing capability, and wherein the one server communicates to the another server at the compatible level of timing capability indicated by the negotiated version number, and the one server communicates to the additional server at a level of timing capability supported by both the one server and the additional server.