Protocol for managing information

• US 7,747,770 B1
• Filed: 03/28/2007
• Issued: 06/29/2010
• Est. Priority Date: 03/28/2007
• Status: Expired due to Fees

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: VanRenesse, Robbert
• Primary Examiner(s): Chang; Jungwon
• Application Number:
  US11/692,886
• Time in Patent Office: 1,189 Days
• Field of Search: 707/100, 707/203, 707/1, 707/201, 707/200, 711/159, 711/161, 709/231, 709/220
• US Class Current: 709/231
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes

Abstract

A technique for replicating information among host computing devices based on versions associated with variables of a state on each host computing device is provided. To replicate information among host computing devices, a host computing device determines a maximum variable version of a state among variables. After comparing maximum versions of a state with that of a corresponding state of a connected host, variable values of the state are updated on the host computing device from variable values of the corresponding state on the connected host if it is determined that the maximum variable version on the connected host computing device is greater. The updated variable values correspond to versions on the connected host computing device having a greater version than the maximum variable version on the host computing device.

Claims

1. In a communication system including a plurality of host computing devices connected through a network, an apparatus for managing state information, the apparatus comprising:

a data store for storing information, wherein the information stored on the data store includes state information having two or more variables about a host computing device, each variable associated with a version;

an interface for communicating with a connected host; and

a data processing component having an executable component, which, when executed, the data processing component;

determines a current version value for the state information about the host computing device, wherein the current version value corresponds to a highest version value selected from the version values associated with each of the two or more variables of the state information on the data store;

obtains a remote current version value from the connected host, wherein the remote current version value corresponds to the highest version value selected from the version values associated with each of the two or more variables of corresponding state information about the host computing device on a remote data store;

determines whether the remote current version value is greater than the current version value;

updates values of variables of the state information about the host computing device on the data store associated with values of variables of the corresponding state information about the host computing device on the remote data store if the variables from the remote data store are associated with a version greater than the current version value of the data store.

2. The apparatus of claim 1, wherein the data processing component further transmits to the connected host values for values of variables of the state information about the host computing device on the data store having a version greater than the remote current version value.

3. The apparatus of claim 2, wherein the interface further communicates with the plurality of host computing devices to manage state information, the data processing component, when further executed, repeatedly:

determines the current version value for the state information about the host computing device on the data store;

obtains a remote current version value from a host of the plurality of host computing devices, wherein the remote current version value from the host corresponds to a highest version value selected from the version values associated with each of two or more variables of corresponding state information about the host computing device on a remote data store;

determines whether the remote current version value from the host is greater than the current version value;

updates values of variables of the state information about the host computing device on the data store associated with values of variables of the corresponding state information about the host computing device on the remote data store if the variables from the remote data store are associated with a version greater than the current version value of the data store; and

transmits to the host values of variables of the state information about the host computing device on the data store having a version greater than the remote current version value from the host.

4. The apparatus of claim 2, wherein transmitting to the connected host values of variables of the state information about the host computing device on the data store further includes transmitting the versions associated with each transmitted value of variable.

5. The apparatus of claim 1, wherein the interface for communicating with a connected host includes a connection to a network, the network selected from the group consisting of an intranet network, a wide area network, a local area network, personal area network, and wireless local area network.

6. The apparatus of claim 1, wherein a host computing device is selected from the group consisting of a personal computer, a server computer, a laptop device, a multiprocessor system, microprocessor-based system, network personal computer, minicomputer, and a mainframe computer.

7. The apparatus of claim 1, wherein updating values of variables of the state information about the host computing device on the data store further includes updating the versions associated with each updated value of variable from the corresponding version on the remote data store.

8. A system for managing information between a plurality of hosts, the system comprising:

a first host maintaining at least one state having two or more variables about a host computing device stored in a first data store, each variable associated with a version for tracking the variable and wherein the first host maintains a first current version value for the at least one state corresponding to the highest version value selected from the version values associated with each of the two or more variables of the at least one state on the first data store;

a second host maintaining at least one corresponding state having two or more variables about the host computing device stored in a second data store, each variable associated with a version for tracking the variable and wherein the second host maintains a second current version value for the at least one corresponding state associated with the highest version value selected from the version values associated with each of the two or more variables of the at least one corresponding state on the second data store; and

wherein the first host transmits to the second host for values of variables of the state information about the host computing device, the values of variables transmitted from the first data store having a version greater than the second current version value.

9. The system of claim 8, wherein the first host updates values of variables of the state information about the host computing device on the first data store associated with values of variables of the corresponding state information about the host computing device on the second data store if the variables from the second data store are associated with a version greater than the first current version value of the first data store.

10. The system of claim 8, further comprising:

a third host maintaining at least one state having two or more variables about a host computing device stored in a third data store, each variable associated with a version for tracking the variable and wherein the third host maintains a third current version value for the at least one state corresponding to the highest version value selected from the version values associated with each of the two or more variables of the at least on state on the third data store;

wherein the first host updates for values of variables of the state information about the host computing device on the first data store associated with values of variables of the corresponding state information about the host computing device on the third data store if the variables from the third data store are associated with a version greater than the first current version value of the first data store.

11. The system of claim 10, wherein the first host transmits to the third host for values of variables of the state information about the host computing device on the first data store having a version greater than the third current version value.

12. The system of claim 11, wherein the second host updates values of variables of the state information about the host computing device on the second data store associated with values of variables of the corresponding state information about the host computing device on the third data store if the variables from the third data store are associated with a version greater than the second current version value of the second data store.

13. The system of claim 12, wherein the second host transmits to the third host values of variables of the state information about the host computing device on the second data store having a version greater than the third current version value.

14. The system of claim 8, wherein the two or more variables on the first host include different versions for each variable.

15. The system of claim 8, wherein the two or more variables on the second host include different versions for each variable.

16. In a communication system including a plurality of host computing devices, a method for managing information, the method comprising:

obtaining remote current version values from a connected host, wherein the remote current version values correspond to, for each of one or more states on a remote data store, the highest version value selected from the version values associated with each of the two or more variables associated with each state, wherein each variable has an associated version;

determining whether the remote current version values are greater than corresponding current version values, wherein the corresponding current version values correspond to, for each of the one or more corresponding states on a data store, the highest of the version value selected from the version values associated with each of the two or more variables associated with each state, wherein each variable has an associated version; and

updating values of variables of a corresponding state on the data store associated with values of variables of a state on the remote data store if the variables of the state from the remote data store are associated with a version greater than the current version value of the corresponding state on the data store.

17. The method of claim 16, wherein the method for managing information further comprises transmitting to the connected host values of variables of the corresponding state on the data store having a version greater than the remote current version value associated with the state of the connected host.

18. The method of claim 17, wherein the at least two or more variables for each host include at least one of a message, text, picture, and symbol data.

19. The method of claim 17, further comprising:

repeatedly, for each state on the remote data store and each corresponding state on the data store;

updating values of variables of a corresponding state on the data store associated with values of variables of a state on the remote data store if the variables of the state from the remote data store are associated with a version greater than the current version value of the corresponding state on the data store; and

transmitting to the connected host values of variables of the corresponding state on the data store having a version greater than the remote current version value associated with the state of the connected host.

20. A computer-readable storage media storing instructions for causing at least one processor to perform a method that manages information among a plurality of host computing devices, the method comprising:

determining a current version value of a state on a data store, wherein the current version value corresponds to a highest version value selected from the version values associated with each of two or more variables of the state on the data store with each variable having a version;

obtaining a remote current version value of a corresponding state from a connected host within the plurality of host computing devices, wherein the remote current version value corresponds to the highest version value selected from the version values associated with each of two or more variables of the corresponding state with each variable having a version on a remote data store;

updating values of variables of the state on the data store corresponding to values of variables of the corresponding state on the remote data store if the variables from the remote data store are associated with a version greater than the current version value of the data store;

transmitting to the connected host values of variables of the state on the data store having a version greater than the remote current version value; and

repeating the method until each host within the plurality of host computing devices has the updated values for the state.

21. The method of claim 20, further comprising repeating the method for each state on the data store and corresponding state on the remote data store.