SDN network system, controller, and controlling method

A software defined network (SDN) controller comprising:

• a receiver configured to receive a first message from a first node that belongs to the SDN controller, wherein the first message comprises an identifier of the first node;
• a processor coupled to the receiver and configured to determine whether the first message is a cross-domain message comprising an identifier of a second node belonging to another SDN controller;
• and
• a transmitter coupled to the processor and configured to send a second message to an upper level controller to which the SDN controller belongs in response to determining that the first message is the cross-domain message comprising the identifier of the second node belonging to the other SDN controller,
• wherein the SDN controller and the other SDN controller belong to a same level in an SDN system.

A software defined network (SDN) controlling method implemented by an SDN controller and comprising:

• receiving a first message from a first node that belongs to the SDN controller, wherein the first message comprises an identifier of the first node;
• determining whether the first message is a cross-domain message comprising an identifier of a second node belonging to another SDN controller;
• and
• sending a second message to an upper level controller to which the SDN controller belongs in response to determining that the first message is the cross-domain message comprising the identifier of the second node belonging to the other SDN controller,
• wherein the SDN controller and the other SDN controller belong to a same level in an SDN system.

A software defined network (SDN) controlling method implemented by an SDN controller and comprising:

• receiving a first message from a first lower level controller that belongs to the SDN controller;
• receiving a second message from the first lower level controller in response to determining that the first message comprises an identifier of a node that belongs to a second lower level controller;
• and
• performing decision processing based on status information of the first lower level controller and status information of boundary nodes of the first lower level controller,
• wherein a boundary node of the first lower level controller belongs to the first lower level controller and connects to the node that belongs to the second lower level controller, and
• wherein the first lower level controller and the second lower level controller belong to a same level an SDN system.

A software defined network (SDN) controller comprising:

• a receiver configured to:
• receive a first message from a first lower level controller that belongs to the SDN controller;
• and
• receive a second message from the first lower level controller in response to determining that the first message comprises an identifier of a node that belongs to a second lower level controller;
• and
• a processor configured to perform decision processing based on status information of the first lower level controller and status information of boundary nodes of the first lower level controller,
• wherein a boundary node of the first lower level controller belongs to the first lower level controller and connects to the node that belongs to the second lower level controller, and
• wherein the first lower level controller and the second lower level controller belong to a same level in an SDN system.

A computer program product comprising instructions that are stored on a non-transitory computer readable medium and that, when executed by a processor, cause a software defined network (SDN) controller to:

• receive a first message from a first node that belongs to the SDN controller, wherein the first message comprises an identifier of the first node;
• determine whether the first message is a cross-domain message comprising an identifier of a second node belonging to another SDN controller;
• and
• send a second message to an upper level controller that belongs to the SDN controller in response to determining that the first message is the cross-domain message comprising the identifier of the second node belonging to the other SDN controller,
• wherein the SDN controller and the other SDN controller belong to a same level in an SDN system.

A computer program product comprising instructions that are stored on a non-transitory computer readable medium and that, when executed by a processor, cause a software defined network (SDN) controller to:

• receive a first message from a first lower level controller that belongs to the SDN controller;
• receive a second message from the first lower level controller in response to determining that the first message comprises an identifier of a node that belongs to a second lower level controller;
• and
• perform decision processing based on status information of the first lower level controller and status information of boundary nodes of the first lower level controller,
• wherein a boundary node of the first lower level controller belongs to the first lower level controller and connects to the node that belongs to the second lower level controller, and
• wherein the first lower level controller and the second lower level controller belong to a same level in an SDN system.