Distributed system

• US 20100039944A1
• Filed: 06/08/2009
• Published: 02/18/2010
• Est. Priority Date: 06/27/2008
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Shimamura, Kotaro, Matsubara, Masahiro, Sakurai, Kohei
• Application Number:
  US12/457,329
• Publication Number:
  US 20100039944A1
• Time in Patent Office: Days
• US Class Current: 370/242
• CPC Class Codes: H04L 12/417 with deterministic access, e.g. token passing
• CPC Class Codes: H04L 2012/40241 Flexray
• CPC Class Codes: H04L 2012/4026 Bus for use in automation systems
• CPC Class Codes: H04L 2012/40273 the transportation system being a vehicle
• CPC Class Codes: H04L 41/0677 Localisation of faults
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0817 by checking functioning

Abstract

A distributed system performs fault identification using inter-node monitoring so as to locate a fault with high reliability and ensure consistent recognition about the situation of the fault occurrence among nodes. The process is synchronized with a communication cycle. If a system does not need to perform the fault identification as often as every communication cycle, the frequency of the fault identification should be decreased so as to reduce a load for CPU processing and a consumption of a communication band per unit time.

A distributed system of the present invention includes plural nodes that are connected to each other via a network. Each of the nodes includes a fault-monitoring section, a transmission and reception section, and a fault-identification section. The fault-monitoring section monitors a fault in other nodes. The transmission and reception section transmits and receives data to detect the fault in other nodes via the network. The fault-identification section identifies which node has the fault based on the data. The fault-monitoring section uses one or more communication cycles as a monitoring period; the communication cycles are synchronized between the nodes.

Claims

1. A distributed system comprising plural nodes being connected to each other via a network,

wherein each of the nodes comprises:

a fault-monitoring section for monitoring a fault in other nodes;

a transmission and reception section for transmitting and receiving data to detect the fault in other nodes via the network;

and

a fault-identification section for identifying which node has the fault based on the data, and

wherein the fault-monitoring section uses plural communication cycles as a monitoring period, the plural communication cycles being synchronized between the nodes.

2. The distributed system according to claim 1,

wherein the transmission and reception section includes a monitoring result from the fault-monitoring section in transmission and reception data and distributes transmission and reception of the data into a next monitoring period that is a next period of when the monitoring result is obtained.

3. The distributed system according to claim 1,

wherein the fault-identification section distributes fault identification into a next monitoring period that is a next period of when the monitoring result is obtained by the fault-monitoring section, the monitoring result being included in the data.

4. The distributed system according to claim 1,

wherein the fault-monitoring section, while the distributed system is in operation, changes the monitoring period for each node to be monitored.