Communication control system and communication control method

A communication device in a communication control system, wherein said communication control system includes a plurality of communication devices, and a control server configured to register an entry in a forwarding table included in each of said plurality of communication devices, and to determine route information for said each of said plurality of communication devices, wherein said communication device is any of said plurality of communication devices, said communication device comprising:

• a data forwarding section configured to perform matching of a received traffic and an entry registered in a forwarding table, and, when information contained in said traffic and information contained in said entry match each other, forward said traffic to a route defined in said entry;
• a transaction management section configured to verify, for a sequence of control instructions from said control server, contents of said control instructions from said control server and hold a verification result, wherein said control server acquires said verification result from said each communication device, determines whether a sequence of control can be executed by said each communication device based on said verification result from said each communication device, and, if said sequence of control can be executed, invokes said each communication device to execute said sequence of control;
• and
• a table search section configured to, when said communication device receives a control command for new entry addition instructions to said forwarding table from said control server, with reference to said forwarding table, check whether or not there is any empty entry in said forwarding table,
• wherein, if there is any empty entry, said table search section checks whether or not there is any entry having an inclusion relationship or a partial inclusion relationship in said forwarding table,
• wherein, if there is any entry having said inclusion relationship or said partial inclusion relationship, said table search section checks a priority of said entry and performs said control command from said control server, and
• wherein the communication device, the communication devices and the control server are implemented as a hardware component.

A communication control method, comprising:

• a control server registering an entry in a forwarding table included in each of a plurality of communication devices and determining route information for each of said plurality of communication devices;
• said each of said plurality of communication devices performing matching of a received traffic and an entry registered in a forwarding table, and when information contained in said traffic and information contained in said entry match each other, forwarding said traffic to a route defined in said entry;
• said each communication device, for a sequence of control instructions from said control server, verifying contents of said control instructions from said control server and holding a verification result;
• said control server acquiring said verification result from said each communication device, determining whether a sequence of control can be executed by said each communication device based on said verification result from the each communication device, and, if said sequence of control can be executed, invoking said each communication device to execute said sequence of control;
• said each communication device, when said each communication device receives a control command for new entry addition instructions to said forwarding table from said control server, checking whether or not there is any empty entry in said forwarding table, with reference to said forwarding table;
• said each communication device, if there is any empty entry, checking whether or not there is any entry having an inclusion relationship or a partial inclusion relationship in said forwarding table;
• said each communication device, if there is any entry having said inclusion relationship or said partial inclusion relationship, checking a priority of said entry;
• and
• said each communication device performing said control command from said control server.

A recording medium which records a computer program for executing a part of a communication control method by a communication control system composed of a plurality of communication devices and a control server registering an entry in a forwarding table included in each of said plurality of communication devices and determining route information for each of said plurality of communication devices,

• said computer program comprising code operable to control a computer as each of said plurality of communication devices, the code comprising:
• performing matching of a received traffic and an entry registered in a forwarding table, and when information contained in said traffic and information contained in said entry match each other, forwarding said traffic to a route defined in said entry;
• for a sequence of control instructions from said control server, verifying contents of said control instructions from said control server and holding a verification result, wherein said control server acquires said verification result from said each communication device, determines whether a sequence of control can be executed by said each communication device based on said verification result from the each communication device, and if said sequence of control can be executed, invokes said each communication device to execute said sequence of control;
• when receiving a control command for new entry addition instructions to said forwarding table from said control server, checking whether or not there is any empty entry in said forwarding table, with reference to said forwarding table;
• if there is any empty entry, checking whether or not there is any entry having an inclusion relationship or a partial inclusion relationship in said forwarding table;
• if there is any entry having said inclusion relationship or said partial inclusion relationship, checking a priority of said entry;
• and
• performing said control command from said control server.