Abstract: A packet transfer scheme for transferring packets at a boundary of a plurality networks is disclosed. A network interconnection apparatus (router) communicates with a previous hop node in one of the plurality of networks by a first control message including a first identification information for identifying an upstream path from the previous hop node and a specification information for specifying a group of packets to be transferred on the upstream path, and with a next hop node in another of the plurality of networks by a second control message including a second identification information for identifying a downstream path to the next hop node and a specification information for specifying a group of packets to be transferred on the downstream path.

Abstract: A router device for controlling label switching path set up is disclosed. In the router device, a,policy information indicating a permitted starting point of a label switching path is stored, and a request message that contains a starting point information indicating a starting point node/network of the requested label switching path and a stream information indicating a desired packet stream to be transferred through the requested label switching path is received. Then, whether or not to permit the set up of the requested label switching path is judged by comparing the starting point information contained in the request message with the stored policy information, and the requested label switching path through the router device for the desired packet stream indicated by the stream information contained in the request message is set up when the set up of the requested label switching path is judged as permitted.

Abstract: A packet transfer method at a node device in which the virtual channel merging is unnecessary at the label switch router even when the communication resource reservation or the high priority transfer is requested is disclosed. At each node, one or more virtual channels for a specific flow are set up toward all receivers regardless of whether each receiver requested a communication quality for the specific flow or not, upon receiving a message used in a procedure for reserving the communication quality for the specific flow that is transmitted from an upstream side to a downstream side on a route of the specific flow toward the receivers.

Abstract: A packet transfer scheme in a network system capable of realizing a high speed, large capacity inter-network communication under an internet environment. A network interconnection apparatus (router) has a memory for storing a correspondence relationship between a virtual connection used in receiving a packet from one logical network and a virtual connection used in transmitting a packet to another logical network, and a transfer at a datalink layer is carried out according to the registered correspondence relationship, to effectively form a bypass pipe capable of transferring a packet by an datalink layer level processing alone over a plurality of networks from the transmission terminal to the destination terminal, so that a high speed packet transfer between networks can be realized.

Abstract: A node manages a virtual connection (VC) in a network such that at least one unused virtual connection to the neighboring node is established and registered. When a VC is needed to transmit a packet, the node obtains the required VC by selecting one of the registered unused VCs instead of setting up a new VC. When a VC in use becomes no longer necessary, the node registers the VC as an unused VC instead of releasing the VC.

Abstract: The system defines a dedicated virtual link (DVL) for a specified packet flow. The router receives a datalink frame having a Media Access Control (MAC) address field. An identifier of the DVL allocated between the router and a previous-hop node is written in the frame using the MAC address field. The router refers to a correspondence relationship between the identifier of the DVL and information for designating a next-hop node, based on the identifier of the DVL included in the received frame, and transfers the frame to the next-hop node without network-layer processing.

Abstract: A packet transfer control method and a node device which are capable of providing a dedicated cut-through path for a specific end-to-end packet flow, while reducing a time required until the cut-through path is established, so as to be able to reduce the load of the address analysis processing at the router.

Abstract: A mechanism for performing multicast packet transfer when a certain one of the destination nodes participating in the multicast communication requires resource reservation for a certain packet flow specified among the packet flows to that destination node. A system may transfer multicast packets using a plurality of virtual connections based on which flow the packets to be transferred belong to, so that each node receives the packets without duplication. Alternatively, a system may selectively discard received packets to avoid processing duplicated packets, although duplicated packets are received at each node.

Abstract: A system for forming one point-to-multipoint connection provides various service attributes in an ATM network in response to differences in service attributes requested by receiving parties or differences in available resources. A network node sets up an output VC (Virtual Channel) link to be connected to an input VC link, the VC links being parts of a point-multipoint connection, receives a new VC link set-up request, and adds to the point-multipoint connection, in response to the new VC link set-up request, new output VC link with service attribute different from that of the input VC link.

Abstract: A router device realizing a datagram transfer method for improving the datagram transfer efficiency by ascertaining the transfer target and/or the requested quality of service without referring to the datagram content. The router device has network interfaces connected with networks including at least one virtual connection oriented network, a memory for storing a correspondence between a virtual connection identifier and a transfer target network interface and/or a quality of service, a connection identifier analysis unit for determining a transfer target network interface and/or a quality of service for a datagram entered from one virtual connection, by referring to the memory according to a virtual connection identifier of that one virtual connection. The datagram can be transferred to the determined transfer target network interface, while applying a priority control for datagrams to be transferred by the router device according to the determined quality of service.

Abstract: A network resource reservation scheme capable of making a resource reservation at the IP level according to the resource reservation protocol at a time of data packet transfer at the IP level using ATM networks. A node device requests a change of a virtual connection for transferring data packets to a prescribed virtual connection for providing a service which is capable of changing an amount of resource without reestablishing connections, when a prescribed message of a resource reservation protocol for that virtual connection is received, and transmits the data packets to the prescribed virtual connection established in response to the request. A node device determines a necessary amount of resource according to a requested quality of service described in a received reservation message of a resource reservation protocol.

Abstract: A packet transmission node which realizes a packet transfer scheme in which a plurality of virtual connections for different qualities of service are set up in correspondence to a multicast destination address, and output virtual connection identifiers are stored in correspondence to destination addresses in a routing table, so that a packet is transferred to output virtual connections determined by referring to the routing table according to a destination address of a packet.

Abstract: A packet transfer scheme in a network system capable of realizing a high speed, large capacity inter-network communication under an internet environment. A network interconnection apparatus (router) has a memory for storing a correspondence relationship between a virtual connection used in receiving a packet from one logical network and a virtual connection used in transmitting a packet to another logical network, and a transfer at a datalink layer is carried out according to the registered correspondence relationship, to effectively form a bypass pipe capable of transferring a packet by an datalink layer level processing alone over a plurality of networks from the transmission terminal to the destination terminal, so that a high speed packet transfer between networks can be realized.

Abstract: A router device realizing a datagram transfer method for improving the datagram transfer efficiency by ascertaining the transfer target and/or the requested quality of service without referring to the datagram content. The router device has network interfaces connected with networks including at least one virtual connection oriented network, a table for registering a correspondence between a virtual connection identifier and a transfer target network interface and/or a quality of service, a connection identifier analysis unit for determining a transfer target network interface and/or a quality of service for a datagram entered from one virtual connection, by referring to the table according to a virtual connection identifier of that one virtual connection. The datagram can be transferred to the determined transfer target network interface, while applying a priority control for datagrams to be transferred by the router device according to the determined quality of service.

Abstract: A method of controlling a communication network including VC exchange nodes and VP exchange nodes such that the cell flow of each VP can be maintained within the prescribed characteristic while the end-to-end cell transfer quality for VCs can be estimated easily and accurately.

Abstract: A method of controlling a communication network including VC exchange nodes-and VP exchange nodes such that the cell flow of each VP can be maintained within the prescribed characteristic while the end-to-end cell transfer quality for VCs can be estimated easily and accurately.

Abstract: A traffic supervisory method for supervising a group of packets generated in a terminal according to an assigned traffic characteristic in which the maximum number of packets generated within a regular period time T is set at N comprises respectively counting the number of packets which are generated within regular time periods .alpha.i.multidot.T ({.alpha.i.vertline.1.ltoreq.i.ltoreq.M, 1.ltoreq..alpha.1<.alpha.2<. . . <.alpha..sub.M }) in a packet flow and judging the packets to violate the assigned traffic characteristic in the case where more packets are generated than .alpha.i.multidot.(1+.beta.i).multidot.N({.beta.i.vertline.1.ltoreq.i.ltor eq.M, .beta.1.gtoreq..beta.2> . . . >.beta..sub.M =0}) within at least one regular interval of time .alpha.i.multidot.T.

Abstract: A method of controlling data transmission in the ATM network which establishes simple modes of a network control for a case in which a plurality of cell loss priority levels are involved within the cells of a single virtual channel. The method includes the steps of declaring the traffic characteristics for either the loss intolerable cells only, or the loss intolerable cells and the loss tolerable cells separately, and carrying out at the network a connection admission control by estimating a cell loss rate on a basis of the declared traffic characteristics, such that the cell loss rate for either the loss intolerable cells only, or the loss intolerable cells and the loss tolerable cells separately in the multiplexed virtual channels is secured by the network on a basis of the estimated cell loss rate.

Abstract: A packet network in which the qualities of service can be maintained for different communications of different classes of requirement for quality of service, regardless of types of calls and data. In this packet network, a communication resource is subdivided into sub-resources which are to be allocated to communications classified into communication classes, where an amount of communications within each sub-resource is controlled independently to satisfy a required quality of service. Also, first type of calls for which a ratio of a maxium transfer speed of each call with respect to a transfer speed of multiplexed line of the packet network is greater than a predetermined threshold value, and second type of calls which are not the first type of calls are distinguished, and a priority control to favor the first type of calls over the second type of calls is performed.

Abstract: In a network in which all information from terminals having various traffic characteristics is transmitted/switched by a fixed length block including a virtual channel id, a terminal requesting communication declares destination address information and traffic characteristics of the requested communication upon set-up to a network. The exchange in the network expresses traffic characteristics of an individual terminal and an offered load (estimated cell flow) in the network. The traffic characteristics of each terminal are expressed as a maximum cell flow generated from the terminal in time units .DELTA.(i) (i=1, 2, . . . , n) having n predetermined lengths. The predicated offered load of the line supposing that a new request call is accepted is expressed as an estimated cell flow predicted to be transmitted to the line in the time unit .DELTA.t(i) by using traffic characteristic values of the calls currently transmitting on the line and a new request call.