Abstract: The present invention relates to a system and method for dynamically adjusting the bandwidth of a continuous bit rate virtual path connection established between a source node and a destination node within a packet or cell switching network comprising a plurality of nodes interconnected with transmission links. In the network, a bandwidth management server having access to information concerning network nodes and transmission links is defined. This server is informed each time a virtual path connection or a virtual channel connection is established on the network with an indication concerning the initial bandwidth reserved for said connection. The server detects and shares, on a continuous or periodical mode, the bandwidth which is available on transmission links among the bandwidth adjustable continuous bit rate virtual path connections and determines for each connection a new bandwidth. The source node is informed each time a new bandwidth is computed.

Abstract: A method and a system of network capacity planning for use in a high speed packet switching network. The network comprises a plurality of switching nodes interconnected through a plurality of communication links, each of the switching nodes comprises means for switching packets from at least one input link to at least one output link. Each of the output links is coupled to at least one buffer in the switching node for queuing packets before they are transmitted over the output link. In each of the switching nodes and for each of the output links, a time distribution of the occupancy of each buffer during a predetermined monitoring time period is measured, and stored in a centralized memory location. Then, the buffer occupancy time distribution data are retrieved from the centralized memory location in all the switching nodes, gathered and stored in a network dedicated server.

Abstract: The present invention relates to a method and system of sharing among a plurality of virtual channel connections the bandwidth of a bandwidth adjustable virtual path connection established between a source node and a destination node within a packet or cell switching network comprising a plurality of nodes interconnected with transmission links, said virtual channel connections comprising bandwidth adjustable reserved virtual channel connections with minimum bandwidth reservation and/or reserved virtual channel connections and/or non reserved virtual channel connections with minimum bandwidth reservation or/and totally non reserved connections without minimum bandwidth reservation.

Abstract: A method for establishing a network connection through a link issuing from a physical port is disclosed. The link has an aggregation of connections. The network connection has a required capacity. The method first computes, from mean bit rates of the aggregation of connections, a mean aggregate bit rate over the aggregation of connections. The method secondly computes, from burst durations from the aggregation of connections, a mean aggregate burst duration over the aggregation of connections. The method thirdly computes an equivalent capacity required on the link by the aggregation of connections, the equivalent capacity being a function of the mean aggregate bit rate and the mean aggregate burst duration. The method fourthly computes an aggregate equivalent capacity, the aggregate equivalent capacity being a function of the equivalent capacity and the required capacity of the connection.

Abstract: A method and system for providing secure network connections are provided. When a device resides on a private network such that its address is not commonly available to other devices via a public network, a gateway, firewall or similar device can be used to preserve the address of the private network device in confidence while still allowing a secure, end-to-end connection between the public and private network devices. The gateway or similar device may negotiate separate secure connections, such as Security Associations, with each of the public and private network devices. In this way, encryption parameters of those two devices can be exchanged even though neither need be knowledgeable of the other's actual address. Moreover, the gateway or similar device can perform this function without itself gaining access to the content being transmitted between the public and private network devices.

Abstract: A method and system for implementing secure communications between a plurality of devices are provided. The method and system generally include the provision of at least one common encryption parameter to each of the plurality of devices, as well as an identification of the plurality of devices to one another. This information can be maintained and shared by interaction of the plurality of devices with a designated server device. In this way, a secure, point-to-point connection between at least two of the plurality of devices can be established.

Abstract: A method and system for implementing secure network communications between a first device and a second device, at least one of the devices communicating with the other device via a firewall device, are provided. The method and system may include obtaining an encryption parameter that is shared by the first device, second device and firewall device. A data packet sent by the first device may then be copied within the firewall device, so that decryption of the copy of the data packet within a portion of the firewall device may take place. In particular, the portion of the firewall device in which decryption takes place is defined such that contents of the portion are inaccessible to an operator of the firewall device. Thus, scanning of the decrypted copy of the data packet for compliance with a predetermined criterion may take place within the firewall device, without an operator of the firewall device having access to the contents of the data packet to be transmitted.

Abstract: The present application discloses a method and system of sharing reserved bandwidth among several connections issuing from a same physical port in an origin node of a packet switching communication network comprising a plurality of nodes interconnected with transmission links. At each request for establishing a connection i from an origin node to a destination node, the dependent connection management process: selects for connection i a routing path comprising one or a plurality of links from the origin node to the destination node: identifies on the selected path all consecutive links starting from the origin node and shared with another connection issuing from the same physical port; reserves on each link of these identified consecutive links an aggregate bandwidth for all connections issuing from the same physical port, said aggregate bandwidth being less than the sum of the bandwidth reserved for each connection considered individually.

Abstract: Method of self-learning for a switching node in a data transmission network (10) wherein Internet Protocol (IP) data frames are transmitted between a sending unit (20 or 24) and a receiving unit (22 or 26) via an ingress switching node (12) linked to an egress switching node (16 or 18) by a plurality of intermediate switching nodes (14) interconnected by trunks. The method consists principally in generating, in the input port/trunk interface of the switching node, a switch header including a source identification field, a destination identification field and a temporary label identifying the flow of data in response to its first data frame, this first switch header being concatenated to said data frame before being transmitted to the router interface of the switching node via its switch engine when the data frame does not belong to a known flow of data and the router has to define the routing of the flow of data.

Abstract: A system and method of providing to an Asynchronous Transfer Mode (ATM) access network a standard ATM interface for accessing a non standard ATM bandwidth adjustable virtual path connection established on a backbone network between a backbone source node and a backbone destination node. A standard ATM available bit rate (ABR) virtual path connection is established between the ATM access network and the backbone source node of the bandwidth adjustable virtual path connection. The available bit rate of this ABR virtual path connection is adjusted according to the adjusted bandwidth of the virtual path connection establish on the backbone node.

Abstract: A communication system and method for compressing data in a transmission system wherein multiplexed channels are transported over a transmission network of the type comprising a plurality of switching nodes interconnected by connection lines, the exchange of data signals carried out by switching the channels in the network between two exchange telephone devices, and each of the multiplexed channels transporting data bytes representing the data signals from one source exchange telephone device to one destination exchange device during an exchange of information therebetween through the intermediary of a compression/decompression device.

Abstract: Method and system for assigning labels in a data transmission network in which flows of data, composed of packets, are transmitted from a source node to a destination node through a plurality of switching nodes. The network is further characterized in that a label, identifying each flow of data, is added to each packet of the flow of data before the packet is transmitted from a transmitting node to an adjacent receiving node in the network. This so-called identification label is recognized by the receiving node as the identification of the flow of data to be transmitted. Each node in the network assigns an identification label to the packets when a new flow of data is received by the node. Both the transmitting and receiving nodes in the network generate an identical label for a given flow of data. Thus, the overhead associated with the sending of assigned labels from assigning nodes to corresponding upstream or downstream transmitting or receiving nodes in the network is avoided.

Abstract: This system is made to perform congestion detection and flow control in high speed digital packet switching network (22) carrying discardable and non-discardable traffic. Forward traffic received at a destination system over a first connection from a source system is monitored. If a congestion-indicating bit is detected in a received packet, a backward congestion indicator is set in packets flowing from the destination system to the source system over a second connection. The source system integrates the number of backward congestion indicators received over successive periods of time using a count-up, count-down counter. Specific congestion control actions are taken at the source system as a function of the counter state at the end of each of the successive periods of time. The congestion control actions may include increasing or decreasing the bandwidth allocated to discardable traffic intended to be delivered over the first connection.

Abstract: The present invention is directed to a high speed packet switching network and, in particular to a method and system for minimizing the time to establish a connection between an origin and a destination node. A path calculated at the time the connection is requested is recorded in a Routing Database and updated each time a modification occurs in the network. Furthermore, alternate paths for supporting non-disruptive path switch on failure or preemption, and new paths towards potential destination nodes can be calculated and stored when the connection set up process is idle. These last operations are executed in background with a low processing priority and in absence of connection request.

Abstract: Data communication system of the type wherein a plurality of contiguous transmission networks constitute an Autonomous System (AS) using the Open Shortest Path First (OSPF) protocol for the exchange of information. The system is divided into several areas including an area 0 or backbone responsible for distributing routing information between the other areas. The backbone is divided into two sub-areas and comprises at least a pair of adjacent splitting routers. The first splitting router is included in one sub-area and the second splitting router is included in the other sub-area. The topological data base of each splitting router is configured to define a high metric for the link between the splitting routers in order to prevent any type of data traffic other than link-state messages (LSA) from being transmitted between the splitting routers.

Abstract: Data transmission system for transmitting packets of data from a source workstation (10) to a destination workstation (40) wherein the packets of data are transmitted over at least a first IP network (14) and a second IP network (30) between an ingress node (20) connected to the source workstation in the first network and an egress node (38) connected to the destination workstation in the second network. The system comprises a local reservation server (26) in the first network accessible by the source workstation and a remote reservation server (42) in the second network accessible by the local reservation server. The local reservation server includes connection setup means for setting up a virtual connection meeting a predefined requirement of Quality of Service from the ingress node to the egress node in response to a request from the source workstation and bandwidth request means for requesting additional bandwidth in the second network to the remote reservation server.

Abstract: A method and system for optimizing transmission links bandwidth utilization in an Asynchronous Transfer Mode (ATM) packet switching network including switching nodes interconnected by high speed transmission links, said network being made to transport user data traffic including PTM traffic organized into variable length packets, each packet comprising a variable length data payload and an original fixed length PTM packet header.

Abstract: A method and system for reserving a virtual connection from a source workstation to a destination workstation. Packets of data are transmitted over a network between an ingress node of the source workstation and an egress node of the destination workstation. In accordance with the method of the present invention, a reservation request is delivered from the source workstation to a reservation server. The reservation server includes a user database for storing the identification of each user allowed to access to the reservation server and also stores the rights of each user. The reservation server further includes a network database for storing the information describing a network capacity required to set up the virtual connection. A verification is then performed to determine whether or not the reservation request may be validated in view of user information within said source workstation.

Abstract: A method based on predefined connection priorities for assigning link bandwidth to a requesting user in a high speed digital network interconnecting network users through a path including network nodes connected through high speed links. According to this method, a predefined reservable link bandwidth is split into so-called nominal bandwidth portions and common bandwidth portions, both assignable to the same connections on a priority basis. Each of the common bandwidth priorities is individually related to a nominal bandwidth priority through a predefined relationship, making the common bandwidth priorities always lower than any nominal priority. In this way the requested link connection bandwidth, whatever be its nominal priority, is made preemptable primarily on all common bandwidth, thus avoiding the disruption of any network connection which is already established.

Abstract: An apparatus and method that determines the end-to-end transit delay at each node of a path, in accordance with the selected probability value indicative of the probability to experience a delay at each node that is smaller than the computed transit delay. Then the computed transit delays per nodes are combined to obtain the end-to-end delay of the path, the combination being either an arithmetic operation or a convolution operation. A method to approximate the convolution operation is also disclosed.