Abstract:
Provided are a cluster system, which makes general nodes appear as if they provide seamless services without failure when seen from the outside, and a method for operating the cluster system. The cluster system for operating individual nodes in a distributed management manner includes a board server having a task board registered with a task list, an agent server for managing the task board, and a plurality of general server nodes for performing a corresponding task on the basis of the task list, among which a failed general server node is replaced with another normal general server node.
Abstract:
Provided are a data server, which is added to a digital broadcast emitting system to emit data broadcasting based on the Programming Metadata Communication Protocol (PMCP), a conventional international specification defined to secure inter-operability between devices of a digital broadcast emitting system; a metadata structure for securing inter-operability between devices of the conventional digital broadcast emitting system; a data stream generating device using the metadata structure; and a digital data broadcast emitting system and method thereof. The PMCP extended metadata of the present invention are formed to include channel type metadata which provide system information of a data event constituting a data broadcast program; and Program and System Information Protocol (PSIP) data event metadata which provide identification information, program guide, and encapsulation information of a data event.
Abstract:
An apparatus and method for injecting synchronized stream data into a Motion Picture Experts Group 2 (MPEG-2) video/audio transport stream for a digital data broadcasting service. The apparatus and method for injecting synchronized stream data calculate the injection time point of data access unit (DAU) that forms the synchronized stream data and injects DAU into the MPEG-2 video/audio transport stream based on the calculated injection time point so that the synchronized stream data could be presented smoothly in a receiver. The synchronized stream data injecting apparatus includes: an additional data storing unit, a synchronized stream data selection/establishment unit, a synchronized stream data analyzing unit, a transport stream analyzing unit, a synchronized stream data injection/management unit, a presentation time stamp re-stamping unit and a multiplexing unit.
Abstract:
A journaling method is provided for supporting a recovery when a system is abnormally terminated in a shared disk environment. When a system call operation to take part in a journaling is generated, in order to guarantee a recovery, a transaction is started and new transaction region is assigned. Then, a system is initialized and a transaction type is set up. Lock information on modified data is acquired and added to the transaction so that a transaction manages lock information. A reflection to a disk during a modification of metadata is prevented. Modified metadata added to the transaction and modified information on principal general data are recorded. Then, lock information connected to the transaction is released.