Patent ID: 9338232
Filing Date: 2016-05-10
CPC Classification: H04L,H04W

Claim Text:
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 to store a first server sequence of a first member server in a replication group, wherein the first server sequence is a sequence used to process state update messages for synchronizing the state of member servers in the replication group; a transceiver configured to receive an external message from a service server and to receive a second state update message from a second member server in the replication group including the first member server, the second state update message comprising a second server sequence, wherein the external message contains login or logout information of a user; an external message processing unit configured, in response to receipt of the external message, to update the first server sequence by a predetermined value, to generate a first state update message comprising the first server sequence, and to transmit 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, to update 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 the first server sequence stored in the server sequence storage unit, wherein the service server is external to the replication group and is in a group comprising a plurality of service servers that does not comprise a member server.