Abstract: In a WDM type PON system, each ONU comprises an optical transmitter capable to transmit optical signals with variable wavelengths, an optical signal receiving filter variable its receiving wavelength, and a control unit. An OLT selects in response to a wavelength allocation request from each ONU, a transmitting wavelength and a receiving wavelength out of currently free wavelengths and allocates these wavelengths to the requester ONT. The control unit of the ONU switches the transmitting wavelength of the optical transmitter and the receiving wavelength of the optical signal receiving filter to the wavelengths specified in a response message from the OLT and starts data communication.

Abstract: A gateway selector and a load distribution management device are provided between a user terminal and plural gateway devices. Of response packets received from the plural gateway devices, the gateway selector selects a response packet from a gateway device with a higher priority, according to the priority in a load distribution management table of the load distribution management device. Then, the gateway selector transfers the selected response packet to the user terminal, while discarding a response packet from another gateway device. In this way, it is possible to construct a redundant configuration of the gateway devices, independent of user terminal implementation.

Abstract: In a WDM type PON system, each ONU comprises an optical transmitter capable to transmit optical signals with variable wavelengths, an optical signal receiving filter variable its receiving wavelength, and a control unit. An OLT selects in response to a wavelength allocation request from each ONU, a transmitting wavelength and a receiving wavelength out of currently free wavelengths and allocates these wavelengths to the requester ONT. The control unit of the ONU switches the transmitting wavelength of the optical transmitter and the receiving wavelength of the optical signal receiving filter to the wavelengths specified in a response message from the OLT and starts data communication.

Abstract: A listening-or-viewing charge is differentiated with bit rates depending on distributed programs. A broadband access server for holding user channels by PPP and replicating and transferring multicast packets have a counter for counting the number of distributed multicast packets and the number of distributed bytes at each multicast group address. The counter values (byte counts and packet counts) when a user joins a multicast group and when the user leaves the multicast group and a multicast session ID containing a PPP user ID and a multicast group address are sent to a multicast accounting radius server. The multicast accounting server provides an accounting on a basis of the byte counts, the packet counts, or a bit rate.

Abstract: A packet forwarding apparatus (L2SW) having a frame segmentation function of converting a extended Ethernet frame such as a MAC-in-MAC frame into a plurality of fragment frames when a payload length of the received frame exceeds a standard MTU size communicable in an Ethernet network to be a forwarding destination, by segmenting the received frame into a plurality of data blocks having a size not longer than the MTU size, and a frame assembling function of restoring an original extended frame from a series of fragment frames received from the Ethernet network.

Abstract: The access server receives an authentication packet including an authentication result, a port change setting information, a port change time, a filtering setting information and a filtering time from the authentication server. The access server stores the respective information in the authentication packet into a memory. The access server refers to the memory, and in the case where the port change setting information on an arbitrary user identifier is set to perform port change, when it becomes the port change time, the access server changes the output destination of a packet from a user terminal to, for example, a proxy server B from a proxy server A. Besides, in the case where the filtering setting information on an arbitrary user identifier is set to perform filtering, when it becomes the filtering start time, the access server performs filtering on the port to which the user terminal is connected.

Abstract: In a WDM type PON system, each ONU comprises an optical transmitter capable to transmit optical signals with variable wavelengths, an optical signal receiving filter variable its receiving wavelength, and a control unit. An OLT selects in response to a wavelength allocation request from each ONU, a transmitting wavelength and a receiving wavelength out of currently free wavelengths and allocates these wavelengths to the requester ONT. The control unit of the ONU switches the transmitting wavelength of the optical transmitter and the receiving wavelength of the optical signal receiving filter to the wavelengths specified in a response message from the OLT and starts data communication.

Abstract: An access network system connected to an ISP network including a subscriber authentication server comprised of a plurality of packet forwarding apparatuses each for connecting user terminals to an Internet network via the ISP network and an address pool management server having an address pool management table for holding, as a sub-address pool, a plurality of IP addresses usable over the ISP network. Each of the packet forwarding apparatuses acquires from the address pool management server an IP address to be allocated to the user terminal having requested connection to the Internet when the subscriber authentication server has succeeded in authentication of the user terminal.

Abstract: A listening-or-viewing charge is differentiated with bit rates depending on distributed programs. A broadband access server for holding user channels by PPP and replicating and transferring multicast packets have a counter for counting the number of distributed multicast packets and the number of distributed bytes at each multicast group address. The counter values (byte counts and packet counts) when a user joins a multicast group and when the user leaves the multicast group and a multicast session ID containing a PPP user ID and a multicast group address are sent to a multicast accounting radius server. The multicast accounting server provides an accounting on a basis of the byte counts, the packet counts, or a bit rate.

Abstract: A method for processing data received from at least one of VLANs, the method including: obtaining, based on a VLAN tag included in a MAC header of a MAC frame received from the VLAN and a first destination IP address included in an IP header of the MAC frame, a second destination IP address, changing the first destination IP address of the IP header to the second destination IP address, and generating an IP packet by deleting the MAC header from the MAC frame.

Abstract: An access server starts the individual collection of communication statistics information on each of LCP sessions upon the establishment of a data link, individually collects communication statistics information on each of NCP sessions established on the LCP session, notifies a RADIUS server of the statistics information on the LCP session when the data link is released, and notifies, when the NCP session is released, the RADIUS server of the statistics information on the released NCP session.

Abstract: A packet transfer apparatus which can switch a communication path for each of a plurality of users using the same L2TP tunnel is provided. Packet transfer apparatuses terminating L2TP contain a table specifying a flow threshold level and a priority level of each subscriber; the amount of packet flow of each subscriber is measured in accordance with the information in the table; if the threshold level is exceeded, the packet communication path is switched in accordance with the priority level specified for each subscriber. The OSPF protocol is used to manage the path information, and the information of a plurality of paths to a destination is stored in a path management table. The path is switched by specifying destination routers with the source routing option in the IP header of a packet after L2TP encapsulation.

Abstract: When a user terminal makes a connection request, a router acquires a group address that the user terminal can join from an authentication server. The router gives information of the router to a packet during joining check (Query) and transmits the packet to a layer 2 switch. The layer 2 switch can grasp, by receiving the joining checks which group address the user terminal can join. The layer 2 switch can perform delivery control involving authentication. The layer 2 switch collects information necessary for accounting such as delivery start and end times and traffic and transmits the information to the router. The router creates accounting information on the basis of the information and transmits the accounting information to the accounting server.

Abstract: One physical VLAN server provides a plurality of VLANs with services. VLANs #1 to #3 are connected to the VLAN server though a switching hub. The VLAN server includes server processes #1 to #3 corresponding to the VLANs #1 to #3, respectively, for providing the VLANs with services. The server processes #1 to #3 each have internal IP addresses N1, N2, and N3. The VLAN server has external IP addresses G1, G2, and G3 for the VLANs #1 to #3, respectively.

Abstract: A Layer 2 switch manages distribution destinations of a multicast packet and distributes a copy of the multicast packet, so that the bandwidth wasted in a network is reduced. The Layer 2 switch is disposed between a user terminal and a packet transfer apparatus, which are connected by P2P, has a function to manage connected multicast users, receives a multicast packet on behalf of the users, and distributes a copy, to reduce the bandwidth wasted between the Layer 2 switch and the packet transfer apparatus.

Abstract: In a packet forwarding apparatus including first line interfaces accommodating user terminals, a second line interface connected to a communication node on a session management apparatus side, and a protocol processing unit for updating a connection management table and a header information table when a specific session control packet is received from one of the first line interfaces. Upon receiving a real-time packet from one of the first line interfaces, if a table entry corresponding to the header information of the received packet has been registered in the connection management table, the control unit routes the received packet to one of the first line interfaces after rewriting its header information based on the header information table, and if the table entry has not been registered, the control unit routes the received packet as it is to the second line interface.

Abstract: An LAC manages multicast destinations, and forms and distributes copies of the multicast packets. An L2TP tunnel and an L2TP session are formed between LAC 1-i and LNS 2-i, and LNS 2-i is connected to network NW2 such as the Internet. Data is transferred between a subscriber and the network through the L2TP connection. LNS 2-i and sever S1 are connected through network NW2 which has routers. A packet transfer apparatus enables LAC 1-i to manage subscriber information and to form and distribute copies of the packets to the subscribers when server S1 on network NW2 distributes multicast packets of a program or the like to the subscribers.

Abstract: A spanning tree is formed for each of MST (Multiple Spanning Tree Protocol) instances defined by a VLAN ID and a COS value. Each terminal apparatus specifies the COS value corresponding to the TCP/UDP port number of a Ethernet frame to be transmitted, based on a conversion table indicating the correspondence of a TCP/UDP port number to a COS value and sets the specified COS value to the header of the Ethernet frame. Each of bridges in the transit network specifies the MST instance identifier of a received frame based on a conversion table indicating the correspondence of the MST instance identifier to the combination of a VLAN ID and a COS value and forwards the received frame in accordance with the spanning tree having the specified MST instance.

Abstract: A packet forwarding apparatus comprises a plurality of line interfaces each for communicating with one of user terminals or one of redundant gateways, and a protocol processing unit for controlling packet forwarding among the line interfaces. The protocol processing unit forwards a connection initiation request packet received from a user terminal to the plurality of redundant gateways and forwards to the user terminal only one response packet which is selected according to connection load status information of each gateway stored in a load distribution management table from among a plurality of response packets received from the gateways within a predetermined period of time.

Abstract: In a wide area Ethernet network, an edge side gateway (EGW) acquires layer 2 tunneling control information from an authentication server when a PADI is received from a user terminal, stores the correspondence between the source address of the PADI and the layer 2 tunneling control information in its management table, encapsulates the PADI in accordance with the layer 2 tunneling control information, and transmits the encapsulated PADI packet to the wide area Ethernet network. A core side gateway (CGW) having received the encapsulated PADI packet stores the correspondence between the tunneling control information and the source address extracted from the received packet in its management table, and forwards the PADI obtained by decapsulating the received packet to a broadband access server. Thereafter, each of the EGW and CGW forward received packets for the user after converting their format by referencing to the management tables.