Abstract: In an inter-ring connection method and device interconnecting a plurality of RPR rings, an inter-ring connecting device (interconnecting station) determines whether or not an RPR frame received from one ring is a broadcast frame; and resets, when the RPR frame determined to be the broadcast frame is relayed to another ring, a ttl of the frame so that a predetermined point between the inter-ring connection device itself and another identical inter-ring connection device opposed within a ring to be relayed is a cleave point. Also, topology information of the one ring is transmitted to another ring; topology information of each ring is held in a topology database; and an RPR frame is relayed (unicasted) between the rings by referring to the topology database based on a destination address of the RPR frame.

Abstract: A packet transmitting apparatus according to the present invention includes a plurality of ports. When the same unlearned packets have arrived at the plurality of ports, the packet transmitting apparatus judges through packet processing section that the first arrived one of the packets is a previous arrival packet. Then, through previous arrival group judging section, the packet transmitting apparatus selects from the plurality of ports a plurality of ports satisfying a previous arrival port condition for determining a port at which the previous arrival packet arrives as a previous arrival port. The packet transmitting apparatus judges the thus selected plurality of ports as the previous arrival ports having an equal previous arrival characteristic of packets, and includes the ports in a previous arrival port group.

Abstract: An electrophotographic photoreceptor includes a cylindrical body and a film forming layer formed on an outer surface of the cylindrical body, having a photosensitive layer. The electrophotographic photoreceptor is divided into a first region where an electrostatic latent image is formed and second regions provided at both end portions in an axial direction of the cylindrical body. The second regions include inclined annular surfaces whose outer diameters decrease toward end portions in the axial direction.

Abstract: A communication device configured to control destination of a received packet by implementing address learning, includes an address learning part configured to implement the address learning by using an IP address of the received packet. The communication device may further include a subnet information obtaining part configured to obtain subnet information; wherein the address learning part implements the address learning by using a host address in the IP address in a case where the subnet information can be obtained by the subnet information obtaining part.

Abstract: A learning-target packet to be used for a path learning is selected from among a plurality of packets queued by a relay apparatus. A relationship between a transmission-source address and a first-arrival port for the selected learning-target packet is registered as learning information. A packet corresponding to the registered learning information is transferred to the first-arrival port pertaining to the learning information, and a packet that does not correspond to the learning information is transferred to all ports to which the packet is to be transferred.

Abstract: The present invention relates to an electrophotographic photosensitive member including a cylindrical body and a photosensitive layer. The cylindrical body has provided with an outer circumference, end surfaces and chamfers formed therebetween. and aThe photosensitive layer is formed on the outer circumference of the cylindrical body. The photosensitive layer covers the chamfers. The chamfers have a surface roughness larger than the outer circumference. Preferably, the end surfaces have a surface roughness larger than the outer circumference.

Abstract: When a packet arrives, a packet processing unit judges whether coincident information is present in an identity information table. When no coincident information is present, the packet processing unit registers the entire packet, a hash value of the entire packet, a predetermined part of the packet, or a hash value of the predetermined part of the packet. In addition, the packet processing unit performs identity judgment for the packet based on the information registered in the identity information table.

Abstract: A determining unit determines an allowable rate of data input permitted at a local node. A generating unit generates, when the allowable rate determined by the determining unit is equal to or greater than a target rate of the local node, extended control information including satisfaction information indicating that the target rate is achieved. A transmitting unit transmits the extended control information generated by the generating unit to an upstream node.

Abstract: When an externally received data frame is transmitted at a station of a ring-shaped packet communication network, a congestion point in the communication network is defined as a boundary point, a frame addressed to a station located before the boundary point is transmitted at a first transfer rate, and a frame addressed to a station located after the boundary point is transmitted at a second transfer rate lower than the first transfer rate.

Abstract: A station forming part of a packet ring telecommunications network designed to share available bandwidth of packets transmitted in a first direction through a 0-side transmission line based on information indicated in control frames transmitted in a second direction in an opposite direction to the first direction through a 1-side transmission line forming a double ring together with the 0-side transmission line, provided with a transmission line switching function unit for switching from the 0-side transmission line to the 1-side transmission line to transmit packets to be transmitted and a switching instruction function unit for holding a switching condition of whether or not to start the transmission line switching operation and giving an instruction to start the transmission line switching operation to the transmission line switching function unit when referring to at least the information indicated in the control frames and judging that the switching condition is satisfied and a method for the same, where

Abstract: In an inter-ring connection method and device interconnecting a plurality of RPR rings, an inter-ring connecting device (interconnecting station) determines whether or not an RPR frame received from one ring is a broadcast frame; and resets, when the RPR frame determined to be the broadcast frame is relayed to another ring, a ttl of the frame so that a predetermined point between the inter-ring connection device itself and another identical inter-ring connection device opposed within a ring to be relayed is a cleave point. Also, topology information of the one ring is transmitted to another ring; topology information of each ring is held in a topology database; and an RPR frame is relayed (unicasted) between the rings by referring to the topology database based on a destination address of the RPR frame.

Abstract: An inquiry respondinq apparatus receives an inquiry and stores a response to the inquiry in a first database. The apparatus determines whether or not the first database can be searched for the response to the inquiry, and when it is determined that the first database can be searched for the response to the inquiry, and when it is determined that the first database can be searched, a search for the response is performed. However, when it is determined that the first database cannot be searched, the apparatus transmits the inquiry to an external information processing device, and the apparatus receives a response to the inquiry which is transmitted from the external information processing device. Then, one of the response obtained by searching the first database and the response received from the external device is displayed on a display.

Abstract: A relay device includes a plurality of physical ports physically connected to a plurality of other relay devices on a network to form physical links; a setting unit for setting one or more logical links for each of the physical links; an evaluation unit for automatically adding an evaluated value based on communication characteristics of the logical link when a control packet is received from a first relay device through the logical link or the control packet is transferred to a second relay device through the logical link; and a unit for selecting, when there are a plurality of routes that merge at the relay device, one of the routes based on evaluated values accumulated by the other relay devices.

Abstract: A method for preventing a control packet loop in a network realizing node redundancy or circuit redundancy based on a rapid spanning tree protocol or a multiple spanning tree protocol is disclosed. The method includes the steps of: detecting a loop of a control packet of the rapid spanning tree protocol or the multiple spanning tree protocol; and discarding the control packet by which the loop is detected so as to prevent occurrence of the loop of the control packet.

Abstract: In a flow control method for conducting a flow control in a network in that a variable-length frame is transmitted and a minimum inter frame gap being a fixed length is regulated among frames, by setting each variable-length frame to be a subject of the flow control by adding a value corresponding to a fixed-length portion outside a frame region to a frame length of the each variable-length, it is possible to conduct the flow control precisely and easily, independent of the frame length in the variable-length frame network, and it is possible to improve flexibility of a location where to conduct the flow control.

Abstract: A bridge apparatus is provided, which apparatus includes a tag attaching mechanism for attaching a plurality of VLAN tags to a frame, a queue configured to store the frame according to the VLAN tags attached thereto, and a read control unit configured to control a read rate for reading the frame from the queue. The VLAN tags are stacked, and a first VLAN tag of the stacked VLAN tags is used for user identification, and a second VLAN tag of the stacked VLAN tags is used for base location route identification. Also, band control is conducted based on the VLAN tags.

Abstract: A packet switching device for receiving and forwarding a packet, comprises a counter for indicating a storage capacity of specified packets in stored packets, and means for starting a forwarding restriction of the specified packets if the counter exceeds a preset forwarding restriction start threshold value. The forwarding restriction is a process of, e.g., lowering a priority of the specified packets in the received packets. The packet switching device further comprises means for canceling the forwarding restriction when the counter becomes smaller than a preset forwarding restriction terminating threshold value.

Abstract: A packet switch includes a memory unit for storing a flag for indicating a state of existence of a packet in a buffer memory, a peak cell rate packet interval value for restricting a read-out rate to a peak cell rate or under, and a minimum cell rate counter initial value expressed as a minimum cell rate in a way of making these parameters corresponding to every connection, a peak cell rate counter unit decremented by a predetermined value at every packet read-out timing with the peak cell rate packet interval value serving as an initial value, a minimum cell rate counter unit for retaining a value of a corresponding connection, which is decremented by a predetermined value each time the packet is read out of the buffer memory, and a read-out control unit for setting as a read-out target the packet corresponding to a connection exhibiting a maximum value of product of the maximum cell rate packet interval value and a value retained in the minimum cell rate counter unit at the packet read-out timing.

Abstract: Disclosed is a transmitting apparatus for transmitting a fixed-length cell and a variable-length packet together in one network. A first IF portion of the transmitting apparatus attaches a header corresponding to the protocol of a mixed network to a variable-length packet which arrives from a packet network and transmits it to the mixed network. A second IF portion removes the cell header from a fixed-length cell which arrives from a fixed-length cell network, attaches a header corresponding to the protocol of the mixed network instead, and transmits it to the mixed length. A third IF portion judges whether a data with a header which arrives from the mixed network is a fixed-length cell or a variable-length packet, replaces the header of the mixed network by a cell header if the data is a fixed-length cell and transmits the data to a fixed-length cell network, while removing the header of the mixed network if the data is a variable-length packet, and transmits the data to a packet network.

Abstract: A packet switch includes a memory unit for storing a flag for indicating a state of existence of a packet in a buffer memory, a peak cell rate packet interval value for restricting a read-out rate to a peak cell rate or under, and a minimum cell rate counter initial value expressed as a minimum cell rate in a way of making these parameters corresponding to every connection, a peak cell rate counter unit decremented by a predetermined value at every packet read-out timing with the peak cell rate packet interval value serving as an initial value, a minimum cell rate counter unit for retaining a value of a corresponding connection, which is decremented by a predetermined value each time the packet is read out of the buffer memory, and a read-out control unit for setting as a read-out target the packet corresponding to a connection exhibiting a maximum value of product of the maximum cell rate packet interval value and a value retained in the minimum cell rate counter unit at the packet read-out timing.