Abstract: Disclosed is a packet managing method of a packet forwarding device. The packet managing method includes receiving a packet; extracting flow information from the packet; searching a flow entry associated with the packet; and requesting the flow entry associated with the packet to a controller when a searching operation of the flow entry is failed. The request on the flow entry associated with the packet is not transferred within a reference time.

Abstract: In a software defined network, when an SDN switch receives a packet, the SDN switch calculates a flow entry index using a matching field value belonging to a matching rule that is extracted from the received packet and a flow matching mask field value representing whether a matching field belonging to a matching rule is a field that is designated as a wildcard, processes a packet that is received according to an action that is set to a flow entry that is matched to the flow entry index from a flow table.

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: In a network including a plurality of switches, different priority levels are assigned to different services based on a frequently requested service list provided from an end system including an end host and a server, and a forwarding rule containing path information for forwarding data packets is selectively set according to the priority levels. A first forwarding rule set for a service of the first priority level is loaded to corresponding ones of the plurality of switches.

Abstract: An apparatus for extracting flow information for monitoring a network is provided. The flow extraction apparatus includes a sampling processor that samples a received packet according to a sampling rate, a flow matching processor that searches for a first flow matching rule that is matched to a first packet that is received from the sampling processor among flow matching rules that are stored at a first flow table and that updates first statistical information corresponding to the first flow matching rule according to a search result, and a controller that sets the sampling rate and a flow matching rule to be stored at the first flow 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: Disclosed is a packet managing method of a packet forwarding device. The packet managing method includes receiving a packet; extracting flow information from the packet; searching a flow entry associated with the packet; and requesting the flow entry associated with the packet to a controller when a searching operation of the flow entry is failed. The request on the flow entry associated with the packet is not transferred within a reference time.

Abstract: A network-based mobility system and a handover method in the system are provided. If a mobile terminal having interfaces of different service providers establishes a connection between domains of the different service providers, a new domain to which the mobile terminal is connected sends a notification of the new connection to the existing domain to which the mobile terminal has been connected. If there is a flow binding switch operation caused by the new connection, the existing domain sends a flow binding setup request to the new domain. The new domain sets up flow binding for the mobile terminal. A tunnel for the corresponding flow is set up between the new domain and the existing domain, whereby packets transmitted to the existing domain are forwarded to the new domain through the tunnel.