Abstract: An alert system for a communications network has a plurality of client devices and a plurality of alert servers each adapted to provide alerts to a respective subset of the client devices to provide scalability. Users at the client devices subscribe to receive alerts by selecting a scope of distribution of alerts. The selection involves selecting a type of alert to receive, a level of severity of alerts to receive, and a geographic scope. In response to receiving a request to issue an alert, an alert server notifies the other alert servers of the alert. Each alert server determines which client devices of the respective subset of client devices are to receive the alert. Each alert server then sends an alert message to its client devices that are to receive the alert.

Abstract: A system of hitless restart in a network, where at least one node in the network provides routing control distributed among ingress ports (ingress cards) and egress ports (egress cards), is disclosed. With distributed routing control, each ingress card has its own routing-control software and each egress card has its own routing-control software. When the routing-software at an ingress port or an egress port of a node is restarted, current connections traversing a restarting ingress card or a restarting egress card continue to function normally during a restart period without data loss. The disclosed system is tailored to a multi-protocol label switching (MPLS) network employing distributed-resource-reservation-protocol traffic engineering (RSVP-TE). The system relies on messaging between ingress card control planes, ingress card data planes, egress card control planes, and egress card data planes of a restarting node.

Abstract: A real-time network-analysis system comprises a network appliance and a plurality of management devices. The network appliance continuously monitors an object network and synthesizes a current network image comprising contemporaneous indicators of connectivity, occupancy, and performance of the object network. A management-client device may gain access to the network image for timely control and for use in producing long-term network-evolution plans. To enable the creation of a real-time network image, optimized topology synthesis algorithms are devised to minimize the computational effort. The real-time network-analysis system is adapted for use with an object network employing a variety of routing protocols, such as link-state protocols, and network-management protocols, such as the Simple-Network-Management protocol.

Abstract: Devices, networks and methods relating to routing gateway traffic in a mesh network for wireless access. A mesh network has multiple nodes in at least one gateway node through which all incoming and outgoing data traffic pass through. The nodes provide wireless access to wireless and user devices, each of which is associated with a node in the mesh network. Each gateway node contains a record detailing which nodes are providing wireless access to which wireless end user device and which nodes are associated with which end user devices. This record of each end user device's location is periodically updated as the gateway node periodically receives data from the nodes which detail the device is being serviced by which node. Any incoming data traffic destined for an end user device is encapsulated and routed to the proper node servicing that end user device.

Abstract: A method to trace, detect, discover and monitor the nodes traversed by a light path from its source to its destination in an Optical Communication Network (OCN) is provided. In accordance with the embodiment of the invention, the system examines various provisioned and discovered optical nodes either sequentially or in parallel to determine whether a unique signature (wavekey) associated with the light path is present. Connectivity and mis-fibering problems are detected by sequentially examining provisioned nodes in the light path to determine if the wavekey associated with the light path can be observed. Control Network topology information is utilized to contact all nodes in the network to trouble-shoot mis-fibering problems.

Abstract: The present invention defines a system and methods for distributed RSVP-TE (resource reservation protocol-traffic engineering) hitless graceful restart for a MPLS (multi-protocol label switching) network. The system comprises a plurality of ingress and egress cards, each card having an MPLS control plane forwarding table for reverse and forward traffic outgoing and incoming labels for LSPs (Label Switched Paths) in the MPLS network; the cards having data planes, each card data plane having said forwarding table stored thereon; and a means for providing messaging between the ingress card MPLS control plane, ingress card data plane, egress card MPLS control plane, and egress card data plane. The methods of the embodiments of this invention do not require hitless graceful restart in telecommunications networks with no requirement for GMPLS stack and therefore can be used in both traditional and generalized MPLS networks.

Abstract: In a packet network, on receiving a packet a receiving host determines if the packet has been marked by any of the nodes through which it passed, to indicate congestion at that node, e.g. by checking the CE bit in an IP header. A packet flow control parameter is generated at the receiving side, and sent to the source using an Internet Protocol, as part of the packet acknowledgment, to control the flow of packets from the source, according to the packet flow control parameter. This can reduce control loop delays caused by waiting at the source for a number of acknowledgments to arrive before the congestion level can be calculated. Conditions at the receiver which may be different to those at the source can now be taken into account in the flow control.

Abstract: In a router in a network comprising a source node, and a receiver node, and other nodes, a congestion monitor determines a degree of congestion, which is sent back to the source node, using an OSI network layer protocol. This enables the flow of packets from the source to be controlled more accurately to maintain high throughput with reduced probability of congestion. Using the network layer rather than lower layers can ensure the indication can be carried across the entire network, and not be lost at boundaries between data links making up the network.

Abstract: A client-server architecture includes a plurality of clients and a plurality of servers. Information resources are replicated among the servers. According to one aspect, the invention includes an intermediary device called a “depot” sitting transparently between a client and a pool of servers which have the replicated information resources. The depot dynamically distributes multiple sessions contained in a client request among the servers. This architecture realizes a good granular scaleability of servers, and improved server throughput with a good response time. Multiple depots also realize robustness.