Abstract: An original packet flow mapping apparatus and method based on an overlay network. The original packet flow mapping apparatus may include a packet-in message receiver, a flow controller, an overlay tunnel controller, and an interface, whereby flows can be identified even in a physical network segment on which an overlay link is implemented and then the flow can be mapped to an original flow.

Abstract: A software-defined network (SDN) system and method for implementing the same can construct a network having flexible network topology by abstracting switches and controllers, as well as a host connected to said switches, and controllers, thereby increasing scalability of a hierarchical SDN network. The SDN system includes a host part, an SDN switch part, and an SDN controller part.

Abstract: A system for controlling a carrier virtual network is disclosed. The system includes at least one virtual network controller for controlling resources of a carrier virtual network based on customer request information received from a customer network controller, and at least one physical network controller for controlling resources of a carrier physical network based on a service profile received from the at least one virtual network controller. The at least one virtual network controller interworks with the at least one physical network controller in a one to one, one to N (N is an integer equal to or larger than 2), or N to one correspondence.

Abstract: The Present Disclosure relates to a poke-in connector configured so that a wire can be contacted at the same time it is locked to a terminal, solely by the action of pushing the wire into the terminal. More specifically, it relates to a poke-in connector that facilitates locking and unlocking of a wire. The poke-in connector of the Present Disclosure comprises a terminal where a wire is inserted and locked while making contact, and a housing that covers the terminal and is formed as one piece with a locking release lever that releases the wire from the locked state. The locking release lever comprises a flexible extension part that has elasticity and extends from the housing, and a pressing part that is formed on the terminus of the flexible extension part and enables the removal of the wire by spreading the locking part of the terminal to either side when pressed.

Abstract: A system and method for virtualizing SDN-based network monitoring. The system for includes: an information collector, a monitoring component, an information converter, and a resource allocator, in which a user-defined virtual monitor is included so that integrated monitoring may be performed, and expandability may be guaranteed to dynamically respond to a user's, demands.

Abstract: Disclosed is a vehicle diagnosis system including: a signal-collecting unit disposed at a proper place of the vehicle including CAN(Controller Area Network) communication modules which send a CAN signal to and receive it from a vehicle ECU for controlling states of all parts of the vehicle by a computer, through a CAN and which output an analog signal to a driver driven by the module according to a command from the vehicle ECU, wherein the signal-collecting unit synchronizes and collects the CAN signal and the analog signal at predetermined time intervals; and a diagnosing unit which detects changes of the CAN signal and the analog signal collected in the signal-collecting unit at synchronization collection periods, and if the change of any one of the two signals has not been detected, diagnoses that the CAN communication module outputting the relevant CAN signal and analog signal failed.

Abstract: A server connection apparatus and method for controlling a connection between a plurality of controller servers and a plurality of network devices. The server connection apparatus includes a network connector configured to connect a plurality of controller servers capable of functioning as OpenFlow protocol-based SDN controllers and a plurality of network devices on a data plane and relay transmission and reception of data between the controller servers and the network devices; and a controller configured to create a list of available controller servers by monitoring an operational state of each controller server, select a particular controller server to be in charge of controlling a network device in response to a received request, and then control connection relationships between the plurality of controller servers and the plurality of network devices based on the selection result.

Abstract: A method and apparatus for managing a flow table is provided. The method includes dividing a flow table into a plurality of states according to occupancy levels of the flow table in a network device; and managing the flow table by reflecting the changed state of the flow table.

Abstract: A communication method in a software defined network (SDN) using a hierarchical structure and a system thereof are provided. The communication method includes separating a transport plane and a control plane from each other; hierarchically partitioning the control plane into a plurality of lower-level controllers and a upper-level controller that is configured to integratedly manage the plurality of lower-level controllers; and controlling communication among unit networks or through at least one unit network by using a hierarchical structure of the control plane.

Abstract: In an address resolution system in a centralized network control environment including a plurality of software defined network (SDN) switches, an address resolution protocol (ARP) controller checks whether an ARP table has a MAC address corresponding to the destination IP address of an ARP request packet when the ARP request packet is received from a source host. An SDN controller determines whether to broadcast the ARP request packet according to the existence of the MAC address corresponding to the destination IP address in the ARP table.

Abstract: Provided are a load balancing apparatus, which is configured to prevent an overload from occurring and perform effectively a load balancing operation even for servers distributed throughout a network, and a load balancing method performed using the same. the method may include determining whether a data packet received from a client may be a packet requiring a load balancing operation, determining at least one of physical servers provided in a distributed server farm as an target server to provide a service to the client, depending on the judgment, determining a forwarding path between the client and the target server, determining a header rewriting node, and referring the forwarding path and the header rewriting node to determine a forwarding rule and load the forwarding rule on a switch provided on the forwarding path.

Abstract: A method for managing energy in a sensor network environment using a spanning tree includes the steps of collecting amount of remaining energy of nodes at a predetermined cycle by a base station in a region having a number of clusters a number of nodes forming a spanning tree in each cluster; assigning a number of links for connecting the nodes to each cluster; determining a maximum number of allowable links of the nodes; and updating the spanning tree based on the maximum number of allowable links.

Abstract: Provided are a node device and a method for deciding a shortest path using a spanning tree. The node device includes: a node division unit dividing the node device into sub-nodes as many as the number of nodes connected to the node device when the node device operates an edge node that is located at an end of a backbone network and is in charge of reformatting and routing frames; a spanning tree generation unit generating as many spanning trees as the number of sub-nodes, wherein each of the spanning trees comprises a shortest path to reach the other edge nodes constructing the backbone network from each of the sub-nodes; and a first path decision unit deciding a shortest path from a source node to a predetermined destination node, as a path to be used, based on the spanning trees that are generated by the spanning tree generation unit. The shortest path that is obtained based on the plurality of spanning trees is used as a path to be used such that throughput of traffic is 3 times and 1.

Abstract: A method for managing energy in a sensor network environment using a spanning tree includes the steps of collecting amount of remaining energy of nodes at a predetermined cycle by a base station in a region having a number of clusters a number of nodes forming a spanning tree in each cluster; assigning a number of links for connecting the nodes to each cluster; determining a maximum number of allowable links of the nodes; and updating the spanning tree based on the maximum number of allowable links.