Abstract: A communication node detects a communication fault thereof, and when a communication fault is detected, the communication node determines whether the communication node is included in a transmission path of a data packet with reference to a routing table and transmits the stored communication fault notification message to peripheral communication nodes.

Abstract: A method and apparatus for collaboratively protecting against a Distributed Denial of Service (DDoS) attack are provided. The method performed by a network apparatus includes detecting data suspected as being used in the DDoS attack by monitoring traffic forwarded to a service server, notifying a security apparatus that the detected data is suspected as being used in the DDoS attack, and performing at least one of a first operation and a second operation, the first operation being receiving an analysis result for the detected data from the security apparatus and controlling the traffic based on the analysis result, and the second operation being controlling, prior to the first operation, the traffic based on a rule set in advance.

Abstract: In a system for providing an IPTV service, if a multicast address of an IPTV channel received from a head-end is a multicast address requested by a mobile node through a tunnel, an end router confirms a care of address (CoA) of the mobile node corresponding to the multicast address of the IPTV channel, sets the multicast address in the first header of broadcasting traffic, sets the CoA of the mobile node in the second header of the broadcasting traffic, and then sends the broadcasting traffic.

Abstract: An apparatus and method for improving the convenience and efficiency of use of the Internet and providing a fundamentally new environment for use of an Internet-based service through automation of authentication for Internet-based service are provided. The apparatus includes an authentication-authorization-accounting (AAA) agent which performs network access authentication such that a user terminal can access a network that the user terminal recognizes, and which performs user authentication required for using Internet-based services according to procedures in accordance with requirements predefined for a user's purpose, wherein the Internet-based services are provided over the Internet by a contents provider. Accordingly, it is possible to reduce costs to be spent on service preparation procedures which are not necessarily related to the actual use of services, and thus the convenience and efficiency of service can be improved.

Abstract: A traffic analysis and flow-based dynamic access control system and method. The flow-based dynamic access control system for controlling a user's access to an internal communication network through an external communication network includes an access control unit operating in an access control mode in which traffic received from a user is basically blocked, generating state management information of a flow, which is received from the user, based on a specified packet of the flow, and verifying whether access of the flow to the internal communication network is a normal access. As a proactive defense concept of allowing only normal users to access an internal network, a method of blocking attacks from a system contaminated by a worm virus, detecting a cyber attack on a certain system in advance and automatically avoiding the cyber attack, and guaranteeing the quality of normal traffic even under cyber attacks without performance degradation of the internal network is provided.

Abstract: Provided are system and method for multi-protocol label switching (MPLS) label-switched path (LSP) protection switching in an MPLS system employing a working LSP and a protection LSP in a 1:1 mode, The system includes: an ingress node multicasting input MPLS traffic through the working LSP and the protection LSP using a fed-back BDI signal; a transit node relaying the MPLS traffic input from the ingress node, and generating a FDI signal when the failure occurs; and an egress node extracting the MPLS traffic from the MPLS LSP input from the transit node, and when the FDI signal is detected, inserting and feeding back the BDI signal to the ingress node through a return path and performing switching to the protection LSP.

Abstract: Provided are a method for measuring an end-to-end delay, and asynchronous packet transmitter/receiver, capable of conveniently and exactly measuring a packet delay in an asynchronous packet transfer network in which a transfer priority is determined as in MPLS. The method includes the steps of continuously transmitting a higher priority packet and a lower priority packet at an ingress node, measuring a time when the higher priority packet arrives at an egress node, measuring a time when the lower priority packet arrives at the egress node, and calculating a delay time from the arrival time of the higher and lower priority packets.

Abstract: Provided is a mobility supporting method of a mobile router. The method includes generating an area identifier to identify an open shortest path first area; and transmitting routing information including the area identifier to an access router.

Abstract: Provided are a method and system of providing a multimedia service in an information provider (IP) network, wherein the method is performed by a system of providing an IP-based mobile service. The method includes: detecting whether a user, who is being provided with the multimedia service, changed from a first terminal to a second terminal; obtaining characteristic information of the second terminal; and providing the multimedia service after changing the multimedia service according to the obtained characteristic information. When only a terminal changes and an access network does not change, or when only an access network changes and a terminal does not change, a network automatically recognizes characteristics of the terminal and the access network and automatically changes media according to the recognized characteristics. Accordingly, a multimedia service without quality deterioration is received, and moreover, a service that can satisfy characteristics (capacity, size of display, etc.

Abstract: Disclosed are a mobile gateway apparatus and a method of connecting IP based services using the same. The mobile gateway apparatus assigns identifiers to user terminals that have accessed the mobile gateway apparatus through multiple internal interfaces based on various network access standards, and selects an appropriate external interface from multiple external interfaces based on various network access standards, thereby providing IP based services Even if the user terminals and the external networks operate based on various network access standards, the mobile gateway apparatus allows IP based services to be effectively provided to the user terminals by supporting more various network access standards while ensuring higher bandwidth.

Abstract: A multicasting method and apparatus in a network including a transport multiprotocol label switch (T-MPLS) network and a wavelength division multiplexing (WDM) network are disclosed. At least one of first switches, connected to the T-MPLS network, second switches connected to the WDM network, and a switch hub establishes a multicasting path by using a label switch path (LSP) ID and a label switch router (LSR) ID, in which the first switch on the multicasting path multicasts a T-MPLS signal, the switch hub converts the T-MPLS signal into an optical multicasting signal and multicasts the converted optical multicasting signal, and the second switch receives the optical multicasting signal and multicasts it in units of the T-MPLS signal.

Abstract: There is provided a converged access control method using a network access device at an edge node of an IP network of a convergence ALL-IP network that performs authentication control, QoS control, traffic control and mobility control in a consistent manner using a network access device located at penetration nodes of an IP network of a convergence ALL-IP network to effectively accommodate a subscriber network in various access environments, thereby ensuring network flexibility and scalability.

Abstract: There are provided a method and a system for providing a source specific multicast service on an Ethernet network. The system includes: a router managing a subscriber; a user terminal transmitting an IGMP packet to the router and transmitting channel reception information that uses an MAC address of the router as a destination MAC address; and an Ethernet switch receiving the channel reception information from the user terminal, determining whether there is a channel subscriber in a port to which the channel reception information has been input based on the contents of the channel reception information, and then outputting a frame that has a channel MAC address, which is the same as that of the channel reception information, as a destination address to the input port in a case where there is a channel subscriber in the input port.

Abstract: There is provided a method and system for detecting and responding to harmful traffic. The system includes a router determining whether or not received data is harmful traffic, by using a dynamic flow identification (DFI) function and a deep packet inspection (DPI) function, sending Cflowd information of the received data, and then encapsulating the received data when the received data is determined to be harmful traffic, a policy & resource control entity receiving the Cflowd information from the router, determining whether or not the received data is harmful traffic by using the received Cflowd information, and then sending a result of the determination to the router, and a security management server receiving the encapsulated data from the router, reconfirming whether or not the encapsulated data is harmful traffic, and then processing the encapsulated data.

Abstract: Provided are a network resource control method and apparatus for guaranteeing an admission rate of a high-priority service. In the method and apparatus, the admission rate of the high-priority service is increased by differentiating between the high-priority service and a low-priority service by either rejecting the low-priority service or reducing a bandwidth allocated to the low-priority service when the low-priority service has already been accepted.

Abstract: An Internet Protocol Television (IP-TV) broadcasting service system and method using a physical layer multicast switch are provided. The system comprises: a head end which converts an Ethernet signal to a virtual concatenation group (VCG) signal of a synchronous digital hierarchy/synchronous optical network (SDH/SONET); a multicast switch which multicasts the VCG signal in a physical layer; and a tail end which receives the multicasted VCG signal through a Synchronous Transmission Module level n (STM-N) optical link and restores the VCG signal to the Ethernet signal. Therefore, high quality TV broadcasting can be provided in an IP multicast network.

Abstract: A system for and a method of providing IPTV service in a next generation network are provided. The system includes a service control unit, a transmission control unit, and an L2 switch unit. A service control unit authenticates a user terminal by receiving a request for providing a service from the user terminal which desires to receive the IPTV service and search for subscription information including the IPTV service for which the user has watching authority, when the user is an IPTV service subscriber. A transmission control unit extracts identification information of the user and a multicast address through which the IPTV service is provided from the subscription information found by the service control unit.

Abstract: Provided are a method and apparatus for blocking forged multicast packets.

Abstract: Provided is a method for measuring performance of a multi-protocol label switching label switched path (MPLS LSP), using a fast failure detection (FFD) packet among MPLS operation and management (OAM) packets recommended by International Telecommunication Union-Telecommunication standardization sector (ITU-T) Y.1711 to detect a packet error generated in the MPLS LSP and newly defining bytes not used in the FFD frame to use the bytes for parity check. An ingress node performs the steps of: calculating a parity value of an MPLS packet as byte interleaved parity (BIP)-8 before transmitting the MPLS packet; storing the calculated parity value of the MPLS packet in an MPLS OAM packet of an FFD structure; and transmitting the MPLS OAM packet whenever transmitting the MPLS packet.

Abstract: A call control method for an Internet Protocol (IP)-based mobility service is provided. The call control method for ensuring service continuity in a mobile communication service environment, includes: receiving a call signal message including permanent IP addresses and transport IP addresses from a transmitter terminal and a receiver terminal, and acquiring the permanent IP addresses and the transport IP addresses of the transmitter terminal and the receiver terminal; and performing call control between the transmitter terminal and the receiver terminal on the basis of the transport IP addresses and the permanent IP addresses of the transmitter terminal and the receiver terminal.