Method and System For Synchronizing Status of Member Servers Belonging to Same Replication Group

• US 20080215760A1
• Filed: 05/25/2006
• Published: 09/04/2008
• Est. Priority Date: 05/31/2005
• Status: Active Grant

• Current Assignee: NHN Entertainment Corporation
• Original Assignee: NHN Corporation
• Inventors: Kim, Seonghun, Song, Gyehan
• Granted Patent: US 9,338,232 B2
• Time in Patent Office: Days
• US Class Current: 709/248
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services

Abstract

A system for synchronizing a state of a member server with a state of other member servers belonging to a same replication group, the system including: a server sequence storage unit storing a first server sequence; a message receiving unit receiving an external message from a service server and receiving a second state update message from a second member server belonging to the same replication group including the member server, the second state update message including a second server sequence; an external message processing unit, in response to the receiving the external message, increasing the first server sequence by a predetermined value, generating a first state update message including the first server sequence, and transmitting the first state update message to the second member server; and a state update message processing unit, in response to the receiving the second state update message, changing the first server sequence to the second server sequence when the second server sequence included in the second state update message is larger than the first server sequence stored in the server sequence storage unit.

Claims

1. A system for synchronizing a state of a member server with a state of other member servers in a same replication group, the system comprising:

a server sequence storage unit configured for storing a sequentially numbered first server sequence of a first member server in a replication group;

a message receiving unit configured for receiving an external message from a service server and receiving a second state update message from a second member server in the replication group including the first member server, the second state update message including a second server sequence, wherein the external message contains login/logout information of a user;

an external message processing unit configured, in response to receipt of the external message, for updating the first server sequence by a predetermined value, generating a first state update message including the first server sequence, and transmitting the first state update message to the second member server; and

a state update message processing unit configured, in response to receipt of the second state update message, for updating the first server sequence with the second server sequence when the sequence value of the second server sequence included in the second state update message is larger than one of the first server sequence stored in the server sequence storage unit.

2. The system of claim 1, further comprising:

a message sequence determination unit configured for determining a sequence of the first state update message and the second state update message in accordance with the sequence values of the first server sequence of the first state update message and the second server sequence of the second update message.

3. The system of claim 1, wherein:

the external message processing unit stores the first state update message in a memory and

the state update message processing unit stores the second state update message in the memory.

4. The system of claim 1, wherein:

the external message includes a user identifier of the user and a login/logout state of the user;

the external message processing unit, in response to receipt of the external message, updates increases the first server sequence by a predetermined value, generates the first state update message including the first server sequence, a user identifier of the external message, and a login/logout state of the user of the external message, and transmits the first state update message to the second member server.

5. The system of claim 4, wherein the second state update message includes the user identifier of the user and the login/logout state of the user, further comprising:

a message buffer for storing the first state update message and the second state update message; and

a user state identification unit configured for determining a final log state of the user according to a sequence of the server sequence included in the state update message stored in the message buffer.

6. The system of claim 5, wherein:

the external message, the first state update message, and the second state update message include location information with respect to a channel through which the user logs into and logs out; and

the user state identification unit determines a final location of the user according to the sequence of the server sequence included in the state update message stored in the message buffer.

7. The system of claim 1, wherein:

the external message processing unit sends the first state update message including a first server identifier for identifying the member server to the second member server;

the second state update message includes a second server identifier for identifying the second member server; and

the message sequence determination unit, when the first server sequence of the first state update message is identical with the second server sequence of the second state update message, determines a sequence of the first state update message and the second state update message by using the first server identifier of the first state update message and the second server identifier of the second state update message.

19. The system of claim 1, wherein the first sequence has a predefined initial sequence value.

20. The method of claim 1, wherein the first sequence has a predefined initial sequence value.

8. A method of synchronizing location servers in a replication group, the method comprising:

maintaining a sequentially numbered first server sequence in a first location server;

receiving a log message from a service server, wherein the log message contains login/logout information of a user;

upon receiving the log message updating the first server sequence by a predetermined value and generating a state update message wherein the state update message includes the first server sequence;

transmitting the generated state update message to other location servers in the replication group including the first location server;

receiving a state update message from a second location server in said replication group, the received state update message including a sequentially numbered second server sequence of the second location server; and

updating the first server sequence maintained in the first location server with the second sequence included in the received state update message when the sequence value of the second server sequence included in the received state update message is larger than one of the first server sequence maintained in the first location server.

9. The method of claim 8, further comprising storing the generated state update message in a message buffer.

10. The method of claim 8, further comprising storing the received state update message from the second location server in a message buffer.

11. The method of claim 8, further comprising determining a sequence of the state update messages in accordance with the server sequences included in the respective state update messages.

12. The method of claim 8, wherein each of the state update messages includes a user identifier of a user and a login or logout state of the user.

13. The method of claim 8, wherein:

a first server identifier is maintained in the location server; and

in the generating of the state update message including the first server sequence, the state update message including the first server sequence and the first server identifier is generated;

the state update message received from the other location server includes the first server sequence and a second server sequence; and

when the server sequence included in the state update message stored in the message buffer is identical, the sequence of the state update message is determined by using the server identifier included in the state update message.

14. The method of claim 13, wherein the first server identifier is an IP address of the location server and the second server identifier is an IP address of the other location server.

18. A computer-readable recording medium in which a program for executing the method recited in claim 8.

21. The method of claim 12, further comprising determining a final log state of the user based upon the updated first server sequence included in the state update message.

15. A method of synchronizing a first member server with a second member server in a replication group, the method comprising:

maintaining a first server sequence and a first server identifier in a first member server;

receiving an external message from a service server, wherein the external message contains login/logout information of a user;

upon receipt of the external message, updating the first server sequence by a predetermined value and generating a first state update message including the first server sequence and the first server identifier;

transmitting the first state update message to a second member server;

receiving a second state update message from the second member server, the second state update message including a second server sequence and a second server identifier;

upon receipt of the second state update message, updating the first server sequence maintained in the first member server with the second server sequence when the second server sequence included in the second state update message is greater than the first server sequence maintained in the first member server; and

determining a sequence of the first state update message and the second state update message in accordance with size of the first server sequence of the first state update message and the second server sequence of the second state update message.

16. The method of claim 15, further comprising determining the sequence of the first state update message and the second state update message in accordance with size of the first server identifier of the first state update message and the second server identifier of the second state update message when the first server sequence of the first state update message and the second server sequence of the second state update message has the same sequence value.

17. The method of claim 15, wherein the first state update message and the second state update message include a user identifier of a user, a login/logout state of the user, and location information associated with a channel in which the user logs into/out of, and the method of claim 15 further comprising determining a final log state of the user by storing the first state update message and the second state update message in a message buffer and processing the message according to the determined sequence of the first state update message and the second state update message.

22. A method of synchronizing a first location server with a second location server in a group wherein the location servers manage log status of a plurality of service servers, the method comprising:

maintaining a first server sequence containing a sequential value;

receiving an external message from a first service server by the first location server wherein the external message contains login/logout information of a user;

upon receipt of the external message, updating the first server sequence by a predetermined sequential value;

generating a first state update message for the first location server wherein the first state update message includes the updated first server sequence and the log status of the first service server contained in the received external message;

transmitting the first state update message to a second location server;

receiving a second state update message from the second location server wherein the second state update message includes a second server sequence and the second server sequence contains a sequential value; and

upon receipt of the second state update message, updating the first server sequence maintained in the first location server with the second server sequence in accordance with the sequential values of the first server sequence maintained in the first location server and the second server sequence included in the received second state update message.