Abstract: In order to specify a data discarding point in a network, provided is a network system for collecting, in the network including an access network and a transport network, pieces of statistical information including a traffic amount of the network, including: an access terminal coupled to the access network; and an edge node for interconnecting the access network and the transport network, in which: the access terminal is configured to: measure pieces of statistical information including a traffic amount in the access terminal; and notify the edge node of the measured pieces of statistical information; and the edge node collects the pieces of statistical information notified by the access terminal.

Abstract: When data is disclosed to a plurality of users by using a transfer network and a transfer apparatus, data disclosure time control which cannot be adversely affected by the users is performed to reduce the difference in data disclosure time among the users. A transfer network system includes a distribution server serving as a data-distribution-source transfer apparatus, and a network terminal connected to distribution-destination user equipment. The distribution server and the network terminal each have a time keeping function and a time synchronization function for matching the time of the time keeping function with a master clock. The distribution server sends in advance disclosure data and disclosure time to the network terminal. When the time of the time keeping function of the network terminal matches the disclosure time, the network terminal sends the disclosure data to the user equipment.

Abstract: An interconnection between fully synchronous networks and next-generation frame communications networks is disclosed. A means of bidirectional frame format conversion between a synchronous multiplexing system and a logical multiplexing system is provided, along with a method of transmitting data between different networks on a path as if it were being transmitted in the same network. Further, when converting network control information in an STM network into data suitable for a packet network, even across the boundary of a synchronous multiplexing system and a logical multiplexing system, a unified communication management means is provided over the whole path.

Abstract: A packet transfer apparatus connects two networks of different protocols. The packet transfer apparatus, connected to a first communication network and a second communication network, performs the steps of: storing first destination correspondence information; receiving a packet of the first communication protocol; based on the first destination correspondence information, determining destination information of a packet of the second communication protocol corresponding to destination information of the received packet of the first communication protocol; generating the header of the packet of the second communication protocol, based on the determined destination information of the packet of the second communication protocol; converting the received one or more packets of the first communication protocol into one or more packets of the third communication protocol; and adding the generated header of the packet of the second communication protocol to the packets of the third communication protocol.

Abstract: When multiple SDH/SONET frame are accumulated and then lower-order path information removed from multiple frames is multiplexed into the same packet to achieve better transmission efficiency during packetization, the delay for accumulating increases. Disclosed is a transmission device that packetizes an SDH/SONET lower-order path with timing which is an integer factor of 1 cycle of the SDH frame. In this case, the destination loads the same multiple lower-order path in one packet. The result is that delay time accompanying lower-order path packetization is kept to less than the time of 1 cycle of the SDH frame, and the efficiency with which lower-order paths are accommodated in packets is further increased. The result is that improved transmission efficiency is realized.

Abstract: A communication device on a time equivalence assurance network that guarantees the receiving sequence of packets sent to all users so that even if a user session is re-sent, a function operates to alleviate the resultant effects and make the send and receive timing approach the initial timing. An edge communication device on a provider network identifies the sessions of each user subscriber terminal, and stores and monitors the time information attached by a sequence information attachment function. Even if a packet is resent, the packet will at this time be resent with attached sequence information based on the past time originally attached to the packet, and not sequence information based on the current resending time.

Abstract: A packet transfer apparatus connects two networks of different protocols. The packet transfer apparatus, connected to a first communication network and a second communication network, performs the steps of: storing first destination correspondence information; receiving a packet of the first communication protocol; based on the first destination correspondence information, determining destination information of a packet of the second communication protocol corresponding to destination information of the received packet of the first communication protocol; generating the header of the packet of the second communication protocol, based on the determined destination information of the packet of the second communication protocol; converting the received one or more packets of the first communication protocol into one or more packets of the third communication protocol; and adding the generated header of the packet of the second communication protocol to the packets of the third communication protocol.

Abstract: Switching process at the occurrence of a path trouble is performed more quickly to reduce the number of packet discards during a traffic transition from a currently used system path to a standby system path within a section to be protected. An OLT (210-W) refers to the DBA information of a PON section and, if receiving no CCM frame at a timing at which the same should be received, then determines that some trouble has occurred on the path (S801) and transmits, to an OAM-compliant NE (200-Z), an application-for-switching frame (1501) to notify the OAM-compliant NE (200-Z) of the abnormal condition. The OAM-compliant NE (200-Z) monitors the occurrence of the trouble within the PON section nearly in real time, starts a switching process (S802) and generates and transmits a standby-system delivery request (321) (S302, S803). An OAM-compliant NE (200-A) switches the communication path to the standby-system passing through an OLT (210-P).

Abstract: Packet transfer device and method have both a processing procedure for uninterruptible-switching desiring packets and a processing procedure for low-delay desiring packets, and process each user packet according to a desired one of the processing procedures. The uninterruptible-switching desiring packets are set to be in phase by a delay unit and written into an uninterruptible-switching memory. The low-delay desiring packets are written into a low-delay memory without passing trough the delay unit, that is, without being delayed. A read-out controller reads out a packet from the uninterruptible-switching memory. When the read-out packet is an uninterruptible-switching desiring packet, the packet is directly output, and when the read-out packet is a low-delay desiring packet, the packet is discarded, and a low-delay desiring packet is read out from the low-delay memory and output.

Abstract: A transmission network is comprised of a network management system for collectively managing and controlling a plurality of transmission devices coupled mutually through transmission routes and the transmission network as well. The network management system includes a plane management table adapted to manage transmission planes defined as a set of paths in the transmission network, and the plane management table has the function to set and manage a transmission plane (working plane) applied during normal operation and besides, a single or a plurality of transmission planes (protection planes) applicable in the event of occurrence of a fault in the transmission network. Then, when a fault occurs in the transmission network, the network management system changes the applied plane to a suitable transmission plane.

Abstract: Disclosed herewith is a packet transfer apparatus that carries out 1+1 protection switching for traffics to be received variably in both length and cycle. The apparatus enables flows to be multiplexed and the link usage efficiency to be improved without generating any buffer overflow errors. The data transfer apparatus, upon receiving the third sequentially numbered data from the first communication route before receiving the preceding second sequentially numbered data, stores the received third data in a buffer. And upon receiving the second sequentially numbered data from the second communication route, the apparatus sends the second and third data sequentially. Then, upon receiving the third sequentially numbered data from the second communication route before receiving the second sequentially numbered data, the apparatus sends the third data when a predetermined waiting time expires.

Abstract: A transmitting apparatus includes a plurality of code spreaders different in spreading code, a reception processing unit that selectively distributes transmission data to the plurality of code spreaders, a plurality of optical transmitters each of which that transmit a code-spread signal to an optical fiber as a CDMA optical signal of a carrier wavelength different from that of the other optical transmitters, and a signal multiplexing unit that selectively supplies outputs of the plurality of code spreaders to the plurality of optical transmitters. A receiving apparatus includes an optical receiver that receives a wavelength-division-multiplexed CDMA optical signal from the optical fiber, and a plurality of despreaders connected to the optical receiver and different in spreading code, wherein each of the despreaders reproduces a CDMA signal corresponding to its spreading code from an output signal of the optical receiver.

Abstract: When data is disclosed to a plurality of users by using a transfer network and a transfer apparatus, data disclosure time control which cannot be adversely affected by the users is performed to reduce the difference in data disclosure time among the users. A transfer network system includes a distribution server serving as a data-distribution-source transfer apparatus, and a network terminal connected to distribution-destination user equipment. The distribution server and the network terminal each have a time keeping function and a time synchronization function for matching the time of the time keeping function with a master clock. The distribution server sends in advance disclosure data and disclosure time to the network terminal. When the time of the time keeping function of the network terminal matches the disclosure time, the network terminal sends the disclosure data to the user equipment.

Abstract: A PON system capable of utilizing the bandwidth of an optical transmission channel in the PON section. In a PON system including an OLT and a plurality of ONUs, the OLT has: a downstream frame processing unit that removes at least part of the header information in a layer 2 header from a downstream frame received from a wide area network, and converts the remaining frame portion into a frame having a header specific to the PON section; and a downstream frame processing unit that extracts a downstream frame portion to be transferred to a user terminal, from a received frame from a PON, and adds the layer 2 header information deleted in the OLT.

Abstract: An identifier management apparatus capable of setting identifier conversion information of a new user without affecting identifier conversion processings of other users, and an identifier management method. The identifier management apparatus converts an identifier given to communication data. Its memory stores multiple hash functions, output values of the hash functions corresponding to the respective plurality of hash functions, multiple entry tables that manage the identifier conversion information indicating a correspondence between the input identifier being an input value of the hash function and an output identifier obtained by converting the input identifier, and a management table for managing a setting status of the identifier conversion information in each entry table.

Abstract: To prevent, in using a multicast DA in an OAM frame, an increase in the network bandwidth usage and in the load of node processing and a degradation of the network reliability caused by a frame being transmitted to all routes in a broadcast domain. A MAC address and other basic frame information and the MEGID are associated with each other, and the MEGID information is added to the OAM frame, and these information are transmitted from an edge node serving as an end point of an ME. In a relay node of the ME, a route control table used for OAM frame control is provided, and a filter is generated by snooping of the OAM frame. Furthermore, when the relay node does not support the OAM function, the MEGID is denoted by a VLAN tag and the route control is made using the snooping function of each VLAN tag.

Abstract: A shelf of a network synchronization device includes: a clock input reception unit which receives an input of a clock signal; a clock output unit which outputs a clock signal; a clock interruption detection unit which detects a clock interruption if the clock input reception unit does not receive a clock; an AIS signal detection unit which detects an AIS signal if the AIS signal is received through the clock input reception unit; an AIS signal generation unit which generates the AIS signal; an alarm control unit which outputs a predetermined alarm notification when the AIS signal detection unit does not detect the AIS signal if the clock interruption detection unit detects the clock interruption; and an output signal selection unit which outputs the AIS signal generated by the AIS signal generation unit to the clock output unit if the clock interruption detection unit detects the clock interruption.

Abstract: An optical access system capable of avoiding cutoffs or interruption in the periodically transmitted signals that occur during the ranging time is provided. A first method to avoid signal cutoffs is to stop periodic transmit signals at the transmitter during the ranging period, and transmit all the periodic transmit signals together when the ranging ends, and buffer the signals at the receiver to prepare for ranging. A second method is to fix definite periods ahead of time for performing ranging, then cluster the multiple periodic transmit signals together in sets at the transmitter and send them, and then disassemble those sets back into signals at the receiver. The transmitting and receiving is then controlled so that the transmit periods do not overlap with the ranging periods. In this way an optical access system is provided that can send and receive signals requiring periodic transmissions without interruption even during ranging operation.

Abstract: It is ensured to prevent a user from misrepresenting a time stamp, and to send out packets in sequence in which the packets are accepted to all users who are geographically isolated from each other. A unique time stamp impartation function is realized by respective communication devices on a net inside an administrative responsibility range of a communication common carrier, hardly accessible by a user. If a packet with a time stamp imparted by a subscriber terminal, provided thereto, is received, the respective communication devices positioned on the net inside the administrative responsibility range nullify the relevant time stamp in order to prevent misrepresentation of the time stamp, by a user outside the administrative responsibility range, and restores the packet from the subscriber together with the time stamp when transferring the packet to the outside of the administrative responsibility range.

Abstract: Provided is a communication system which is provided with a plurality of communication devices and transfers a packet between the plurality of communication devices through a communication path. When a packet is looped back at any of the communication devices on the communication path to verify connectivity of the communication path, a first communication device of the plurality of communication devices stores, in a first region of header information of the packet, first information for designating the communication device at which the packet is looped back, further stores, in a second region of the header information of the packet, second information on a loopback point in the designated communication device at which the packet is looped back, and sends the packet to which the first information and the second information have been added.