SERVER TIME PROTOCOL MESSAGES AND METHODS

• US 20100223317A1
• Filed: 05/18/2010
• Published: 09/02/2010
• Est. Priority Date: 01/31/2007
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: WIERBOWSKI, Judith A., CRABTREE, Donald, CARLSON, Scott M., DAHLEN, Dennis J., DHONDY, Noshir R., HACK, Michel H.T., SEVIGNY, Denise M., SMITH, Ronald M. SR.
• Granted Patent: US 8,001,225 B2
• Time in Patent Office: Days
• US Class Current: 709/201
• CPC Class Codes: H04J 3/0641 Change of the master or reference, e.g. take-over or failure of the master
• CPC Class Codes: H04J 3/0667 Bidirectional timestamps, e.g. NTP or PTP for compensation of clock drift and for compensation of propagation delays arrangements for monitoring round trip delays in packet switching networks H04L43/0864
• CPC Class Codes: H04L 43/0864 Round trip delays
• CPC Class Codes: H04L 43/106 using time related information in packets, e.g. by adding timestamps
• CPC Class Codes: H04L 67/00 Network arrangements or protocols for supporting network services or applications user-to-user messaging H04L51/00; network arrangements, protocols or services for supporting real-time applications in data packet communications networks H04L65/00

Abstract

Server time protocol (STP) messages and methods of exchange thereof are provided for facilitating synchronization of processing units of a timing network. The STP messages include exchange time parameters (XTP) commands and responses, and STP control (STC) commands and responses. XTP message exchange processing includes: generating an XTP message command at a first processing unit including a command transmit timestamp field set by the first processing unit and a command receive timestamp field which is unset by the first processing unit; transmitting the XTP message command to a second processing unit; setting the command receive timestamp field in the XTP command with the time the XTP command is received at the second processing unit; and generating an XTP message response at the second processing unit, the message response including the command transmit timestamp set by the first processing unit and the command receive timestamp set by the second processing unit.

Claims

1. A method of executing a server time protocol (STP) control message command, the method comprising:

receiving an STP control message command at a second server sent from a first server across an established STP path within a coordinated timing network (CTN), the first server and the second server communicating at a same STP version across the established STP path, the STP control message command being defined for computer execution according to a computer architecture, and the STP control message command comprising an operation code field containing a value that specifies an operation to be performed;

responsive to receiving the STP control message command, performing an operation at the second server defined by the operation code of the STP control message command and providing a result based thereon, the result being operation dependent; and

sending an STP message response from the second server to the first server, the STP message response comprising the result of performing the operation specified in the STP control message command.

2. The method of claim 1, wherein the STP control message command further comprises a message header dependent on a type of data link over which the STP path is established between the first server and the second server, a command code field set to a value defined for STP control message commands, and a coordinated timing network (CTN) identifier of the first server which sent the STP control message command.

3. The method of claim 2, wherein the STP control message command further comprises an operation dependent data field including data dependent on the operation code specified in the STP control message command.

4. The method of claim 3, wherein the STP control message command further comprises a message command transmit timestamp field and a message command receive timestamp field, the message command transmit timestamp field having been set from a time of day clock at the first server at the time the STP control message command was transmitted over the established STP path to the second server, and the message command receive timestamp field being set to the time at which the STP control message command is received at the second server, wherein the message command receive timestamp field is set from a time of day clock at the second server when the STP control message command is received.

5. The method of claim 1, wherein the STP message response comprises a response code comprising an integer describing the result of performing the operation at the second server defined by the operation code of the STP control message command, and an operation dependent data field containing data dependent on the operation code specified in the STP control message command.

6. The method of claim 5, wherein the STP message response further comprises a message header dependent on the type of data link over which the STP path is established between the first server and the second server, and a coordinated timing network (CTN) identifier of the second server sending the STP message response.

7. The method of claim 6, wherein the STP message response further comprises a message response transmit timestamp field set from a time of day clock at the second server to the time the STP message response was transmitted over the established STP path to the first server, and a message response receive timestamp field for containing the time at which the STP message response is received at the first server.

8. The method of claim 1, wherein the operation to be performed is the request-stratum-1 configuration change operation, the request-stratum-1 configuration change operation notifying an active-stratum-1 server of a CTN-parameter update request, and wherein the STP control message command further comprises an operation dependent data field, the operation dependent data field containing a new stratum-1 configuration that is being requested.

9. The method of claim 1, wherein the operation to be performed is at least one of a read attach server state operation or a read CTN parameters operation, wherein the read attach server state operation returns an attachment state for a node descriptor provided in an operation-dependent area of the STP control message command, and the read CTN parameters operation results in reading CTN parameters from the second server, wherein the CTN parameters to be read are specified in an operation dependent data field of the STP control message command, the operation dependent data field specifying at least one of read general CTN parameters, read new stratum-1 configuration information, read timezone-control-parameters information block, or read current stratum-1 configuration information.

10. The method of claim 1, wherein the operation to be performed is at least one notification operation, wherein the at least one notification operation is employed to establish or remove an STP path, or for communicating between an alternate-stratum-1 server and an arbiter during a stratum-1 takeover, wherein when the at least one notification operation comprises:

the establish-STP-path operation, the establish STP path operation is performed as part of an STP-path initialization procedure to establish a path between two servers, the establish-STP-path operation being employed to exchange and validate parameters associated with the two servers;

the remove-STP-path operation, the remove-STP-path operation removes an established STP path to an attached server, and the sending server sets the path link state to uninitialized as a result of the remove-STP-path operation;

the set-arbiter-takeover mode operation, the set-arbiter-takeover mode operation is issued to an arbiter server by an alternate-stratum-1 server to put the arbiter into takeover mode, and wherein the receiving server returns the arbiter-takeover state flag in a response block;

the reset-arbiter-takeover mode operation, the reset-arbiter-takeover mode operation is issued to the arbiter server by the alternate-stratum-1 server to take the arbiter out of takeover mode; and

the arbiter takeover state active operation, the arbiter takeover state active operation is issued to the alternate stratum-1 server by the arbiter to notify the alternate-stratum-1 server that the arbiter has entered the takeover-active state.

11. A computer program product for executing a server time protocol (STP) control message command, the computer program product comprising:

a storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising;

receiving an STP control message command at a second server sent from a first server across an established STP path within a coordinated timing network (CTN), the first server and the second server communicating at a same STP version across the established STP path, the STP control message command being defined for computer execution according to a computer architecture, and the STP control message command comprising an operation code field containing a value that specifies an operation to be performed;

responsive to receiving the STP control message command, performing an operation at the second server defined by the operation code of the STP control message command and providing a result based thereon, the result being operation dependent; and

sending an STP message response from the second server to the first server, the STP message response comprising the result of performing the operation specified in the STP control message command.

12. The computer program product of claim 11, wherein the STP control message command further comprises a message header dependent on a type of data link over which the STP path is established between the first server and the second server, a command code field set to a value defined for STP control message commands, a coordinated timing network (CTN) identifier of the first server which sent the STP control message command, and an operation dependent data field including data dependent on the operation code specified in the STP control message command.

13. The computer program product of claim 11, wherein the operation to be performed is a request-stratum-1 configuration change operation, the request-stratum-1 configuration change operation notifying an active-stratum-1 server of a CTN-parameter update request, and wherein the STP control message command further comprises an operation dependent data field, the operation dependent data field containing a new stratum-1 configuration that is being requested.

14. The computer program product of claim 11, wherein the operation to be performed is at least one of a read attach server state operation or a read CTN parameters operation, wherein the read attach server state operation returns an attachment state for a node descriptor provided in an operation-dependent area of the STP control message command, and the read CTN parameters operation results in reading CTN parameters from the second server, wherein the CTN parameters to be read are specified in an operation dependent data field of the STP control message command, the operation dependent data field specifying at least one of read general CTN parameters, read new stratum-1 configuration information, read timezone-control-parameters information block, or read current stratum-1 configuration information.

15. The computer program product of claim 11, wherein the operation to be performed is at least one notification operation, wherein the at least one notification operation is employed to establish or remove an STP path, or for communicating between an alternate-stratum-1 server and an arbiter during a stratum-1 takeover, wherein when the at least one notification operation comprises:

the establish-STP-path operation, the establish STP path operation is performed as part of an STP-path initialization procedure to establish a path between two servers, the establish-STP-path operation being employed to exchange and validate parameters associated with the two servers;

the remove-STP-path operation, the remove-STP-path operation removes an established STP path to an attached server, and the sending server sets the path link state to uninitialized as a result of the remove-STP-path operation;

the set-arbiter-takeover mode operation, the set-arbiter-takeover mode operation is issued to an arbiter server by an alternate-stratum-1 server to put the arbiter into takeover mode, and wherein the receiving server returns the arbiter-takeover state flag in a response block;

the reset-arbiter-takeover mode operation, the reset-arbiter-takeover mode operation is issued to the arbiter server by the alternate-stratum-1 server to take the arbiter out of takeover mode; and

the arbiter takeover state active operation, the arbiter takeover state active operation is issued to the alternate stratum-1 server by the arbiter to notify the alternate-stratum-1 server that the arbiter has entered the takeover-active state.

16. A computer system for executing a server time protocol (STP) control message command, the computer system comprising:

a second server for receiving an STP control message command sent from a first server across an established STP path within a coordinated timing network (CTN), the first server and the second server communicating at a same STP version across the established STP path, the STP control message command being defined for computer execution according to a computer architecture, and the STP control message command comprising an operation code field containing a value that specifies an operation to be performed;

responsive to receipt of the STP control message command, the second server performing an operation defined by the operation code of the STP control message command and providing a result based thereon, the result being operation dependent; and

the second server sending an STP message response to the first server, the STP message response comprising the result of performing the operation specified in the STP control message command.

17. The computer system of claim 16, wherein the STP control message command further comprises a message header dependent on a type of data link over which the STP path is established between the first server and the second server, a command code field set to a value defined for STP control message commands, a coordinated timing network (CTN) identifier of the first server which sent the STP control message command, and an operation dependent data field including data dependent on the operation code specified in the STP control message command.

18. The computer system of claim 16, wherein the operation to be performed is a request-stratum-1 configuration change operation, the request-stratum-1 configuration change operation notifying an active-stratum-1 server of a CTN-parameter update request, and wherein the STP control message command further comprises an operation dependent data field, the operation dependent data field containing a new stratum-1 configuration that is being requested.

19. The computer system of claim 16, wherein the operation to be performed is at least one of a read attach server state operation or a read CTN parameters operation, wherein the read attach server state operation returns an attachment state for a node descriptor provided in an operation-dependent area of the STP control message command, and the read CTN parameters operation results in reading CTN parameters from the second server, wherein the CTN parameters to be read are specified in an operation dependent data field of the STP control message command, the operation dependent data field specifying at least one of read general CTN parameters, read new stratum-1 configuration information, read timezone-control-parameters information block, or read current stratum-1 configuration information.

20. The computer system of claim 16, wherein the operation to be performed is at least one notification operation, wherein the at least one notification operation is employed to establish or remove an STP path, or for communicating between an alternate-stratum-1 server and an arbiter during a stratum-1 takeover, wherein when the at least one notification operation comprises:

the establish-STP-path operation, the establish STP path operation is performed as part of an STP-path initialization procedure to establish a path between two servers, the establish-STP-path operation being employed to exchange and validate parameters associated with the two servers;

the remove-STP-path operation, the remove-STP-path operation removes an established STP path to an attached server, and the sending server sets the path link state to uninitialized as a result of the remove-STP-path operation;

the set-arbiter-takeover mode operation, the set-arbiter-takeover mode operation is issued to an arbiter server by an alternate-stratum-1 server to put the arbiter into takeover mode, and wherein the receiving server returns the arbiter-takeover state flag in a response block;

the reset-arbiter-takeover mode operation, the reset-arbiter-takeover mode operation is issued to the arbiter server by the alternate-stratum-1 server to take the arbiter out of takeover mode; and

the arbiter takeover state active operation, the arbiter takeover state active operation is issued to the alternate stratum-1 server by the arbiter to notify the alternate-stratum-1 server that the arbiter has entered the takeover-active state.