Showing papers on "Core router published in 2000"

The click modular router

Abstract: Clicks is a new software architecture for building flexible and configurable routers. A Click router is assembled from packet processing modules called elements. Individual elements implement simple router functions like packet classification, queuing, scheduling, and interfacing with network devices. A router configurable is a directed graph with elements at the vertices; packets flow along the edges of the graph. Several features make individual elements more powerful and complex configurations easier to write, including pull connections, which model packet flow drivn by transmitting hardware devices, and flow-based router context, which helps an element locate other interesting elements. Click configurations are modular and easy to extend. A standards-compliant Click IP router has 16 elements on its forwarding path; some of its elements are also useful in Ethernet switches and IP tunnelling configurations. Extending the IP router to support dropping policies, fairness among flows, or Differentiated Services simply requires adding a couple of element at the right place. On conventional PC hardware, the Click IP router achieves a maximum loss-free forwarding rate of 333,000 64-byte packets per second, demonstrating that Click's modular and flexible architecture is compatible with good performance.

System and method for routing message traffic using a cluster of routers sharing a single logical IP address distinct from unique IP addresses of the routers

Abstract: A router clustering system connects two or more routers to a one or more distinct Internet Service Providers (ISPs) in a complete high-availability arrangement. Typically the two or more routers connect to a plurality of ISPs at a site so that an outage of one ISP does not affect connectivity and availability to the site. The router clustering system typically includes a plurality of clustering units for redundancy that avoids difficulties that arise with a single point of failure. For example two clustering units may be used in an active-passive high-availability configuration. A router cluster creator creates or configures a router cluster. To create a router cluster, an administrator assigns to the cluster a logical Internet protocol (IP) address IPgw and specifies routers that are members of the cluster.

Non-blocking, scalable optical router architecture and method for routing optical traffic

Abstract: A system and method for providing non-blocking routing of optical data through a telecommunications router that allows full utilization of available capacity. The router includes a number of data links that carry optical data packets to and from an optical router. The optical router includes a number of ingress edge units coupled to an optical switch core coupled further to a number of egress edge units. The ingress edge units receive the optical data packets from the data links and aggregate the optical data packets into “super packets” where each super packet is to be routed to a particular destination egress edge unit. The super packets are sent from the ingress edge units to an optical switch fabric within the optical switch core that routes each super packet through the optical switch fabric to the super packet's particular destination egress edge unit in a non-blocking manner (i.e., without contention or data loss through the optical switch fabric). This routing is managed by a core controller that monitors flow information at each ingress edge unit to control the super packet generation and transmission to the optical switch fabric and schedules each super packet to exit the optical switch fabric so as to avoid contention among the plurality of super packets in the transmission between the optical switch fabric and the egress edge units. The egress edge units receive the super packets, de-aggregate the super packets into the original optical data packets, and transmit the optical data packets to the data lines.

Rainbow fair queueing: fair bandwidth sharing without per-flow state

Abstract: Fair bandwidth sharing at routers has several advantages, including protection of well-behaved flows and possible simplification of end-to-end congestion control mechanisms. Traditional mechanisms to achieve fair sharing (e.g., weighted fair queueing, flow random early discard) require per-flow state to determine which packets to drop under congestion, and therefore are complex to implement at the interior of a high-speed network. In recent work, Stoica et al., (1998), have proposed core-stateless fair queueing (CSFQ), a scheme to approximate fair bandwidth sharing without per-flow state in the interior routers. In this paper, we also achieve approximate fair sharing without per-flow state, however our mechanism differs from CSFQ. Specifically, we divide each flow into a set of layers, based on rate. The packets in a flow are marked at an edge router with a layer label (or "color"). A core router maintains a color threshold and drops layers whose color exceeds the threshold. Using simulations, we show that the performance of our rainbow fair queueing (RFQ) scheme is comparable to CSFQ when the application data does not contain any preferential structure. RFQ outperforms CSFQ in goodput when the application takes advantage of the coloring to encode preferences.

An active router architecture for multicast video distribution

Abstract: Video distribution over the Internet poses many challenges. Due to the best-effort nature of today's public data networks, end system applications cannot rely on either bandwidth or delay guarantees. We designed and implemented a prototype of a multicast video distribution architecture involving knowledgeable active routers, a scalable video codec based on the wavelet transformation, and a high-performance video scaling algorithm implemented as a router plug-in. The plug-in scales the video with an average overhead of only 22 /spl mu/s per video datagram and is installed on-the-fly on the routers after the sender starts transmitting video for the first time. Through experiments on our test network, we show that we can dramatically improve the video quality on the receivers (up to 15 dB PSNR) by scaling the video on the routers to almost any target bandwidth. The target bandwidth is evaluated by the router solely based on monitoring of the load situation of the router's downstream links and can be adjusted within 50 ms.

System and method to manage data to a plurality of proxy servers through a router by application level protocol and an authorized list

Abstract: A method and system for managing data traffic between an intranet and the internet The Intranet composed of client computers connected to a router system which bridges the connection to a plurality of proxy servers The proxy servers act as a gateway to the internet and operate on a designated application level protocol The router system redirecting packets based on application level protocols to the proxy servers while checking the destination proxy server with an authorized list The router system blocking or transmitting based on the application level protocol and the authorized server

Method and apparatus for exchanging routing information in a packet-based data network

Abstract: Routing information is exchanged between edge routers in different autonomous systems that independently define their routing policies. A Simple Path Vector Protocol extends the prior art Border Gateway Protocol in a manner that is guaranteed to converge by adding a new attribute to the routing messages sent by an edge router to its peers in the different systems. This attribute is a path history, which is dynamically computed at each router as the routing path to a particular destination is changed. The path history attribute is sent in a routing message by a router to its peers together with the sending router's path to that destination. By observing the dynamic path history that is computed at a router as a received routing message from a peer router that contains a history attribute is processed, a cycle can be identified in the newly computed history and associated with a policy conflict at that receiving router's associated autonomous system. A path whose history contains a cycle is automatically suppressed as a permitted path to that destination.

Micromobility using multicast

Abstract: The invention is a method and apparatus for registering a mobile node in both home and in foreign domains. A base station informs a base station router of the presence of a mobile entering the base station's coverage area by sending a mobile node advertisement message to a base station router. In addition, the mobile node sends a mobile IP registration request to the base station router. The base station router appends a base station router extension message to the mobile IP registration request (which contains an IP address of the base station router) and forwards the mobile IP registration request to a main access router. The main access router appends a multicast address extension to the mobile IP registration reply. The multicast address extension contains the multicast address allocated for the mobile node.

System for routing and switching in computer networks

Abstract: A protocol for a computer network in which routing operation codes (ROCs) in headers of packets transmitted within the network specify to a receiving router which of a number of routing or switching methods to apply to forward associated packets. The packets may be forwarded in any of the following modes: (a) a broadcast mode, (b) a hop-by-hop mode based on receiving node address information, (c) a label swapping mode, (d) a source-switching mode, (e) a flow switching mode, or (f) a hop-by-hop mode based on sending mode address information. In the label swapping mode, packets are accepted by the receiving router if the packets include a media access control address of the receiving router, and packets are forwarded from the receiving router according to a switching table indexed by a media access control address of a transmitting router. In the source switching mode, the header include source routes specified in terms of local link identifiers used by routers in the network. Also, receiving routers are identified using local link identifier associated with communication links between a transmitting router and an intended receiving router.

System, device, and method for controlling access in a multicast communication network

Abstract: A system, device, and method for controlling access in a multicast communication network uses a centralized host authentication scheme to prevent unauthorized hosts from joining a shared multicast distribution tree. Each authorized host is allocated a unique authentication key, which is used by the designated router to encode the PIM join message and by the rendezvous point router to authenticate the PIM join message. If the PIM join message is authentic, then each PIM router from the rendezvous point router to the designated router establishes appropriate multicast routes to route multicast packets to the host. If the PIM join message is not authentic, then multicast packets are prevented from reaching the host.

Internet protocol (IP) class-of-service routing technique

Abstract: The priority of the flow of packets representing calls or other connection requests within a packet network (10) is determined from the Class-of-Service of the call. Upon receipt of a call, a recipient router (12 1 , 12 2 , 12 3) identifies available paths, typically by exchanging messages with the other routers in the network. After selecting the path, the recipient router or centralized bandwidth broker determines whether the links comprising the selected path have available bandwidth for the class of service of the call. If so, the router routes the call to the next hop along the path. Otherwise, the router selects another path(s) and checks whether the links on the path possess sufficient bandwidth for the class of service of the call.

Virtual time reference system: a unifying scheduling framework for scalable support of guaranteed services

Abstract: We propose and develop a novel virtual time reference system as a unifying scheduling framework to provide scalable support for guaranteed services. This virtual time reference system is designed as a conceptual framework upon which guaranteed services can be implemented in a scalable manner using the DiffServ paradigm. The key construct in the proposed virtual time reference system is the notion of packet virtual time stamps, whose computation is core stateless, i.e., no per-flow states are required for its computation. We lay the theoretical foundation for the definition and construction of packet virtual time stamps. We describe how per-hop behavior of a core router (or rather its scheduling mechanism) can be characterized via packet virtual time stamps, and based on this characterization establish end-to-end per-flow delay bounds. Consequently, we demonstrate that, in terms of its ability to support guaranteed services, the proposed virtual time reference system has the same expressive power and generality as the IntServ model. Furthermore, we show that the notion of packet virtual time stamps leads to the design of new core stateless scheduling algorithms, especially work-conserving ones. In addition, our framework does not exclude the use of existing scheduling algorithms such as stateful fair queuing algorithms to support guaranteed services.

Testing of network routers under given routing protocols

Abstract: A network router is tested for operation according to a given network protocol, by coupling the router under test (RUT) to a test host device and arranging the device to simulate operative test network topologies which include router nodes, network nodes, and edges between the nodes. The device exchanges information packets with the RUT for each of a number of successive test network topologies. Each successive topology is determined randomly by inserting or deleting an edge or a node to or from a prior test network topology in a probabilistic manner. Operation of the RUT under the given protocol is evaluated based on the exchanged information packets. A judgment, e.g., a fault or a no-fault condition, is rendered by the host device.

System-resource router

Abstract: A system resource router interfaces initiators through protocol-adapting sockets to a plurality of sub-buses. A switch matrix allows at least some of the sockets to be connected to two or more of the sub-buses. Each sub-bus interfaces through a channel controller to target devices like memory and peripherals. A graphical user interface, assembly program, and computer-aided design platform allow users to customize system resource router configurations for particular applications. At least one embodiment produces Verilog or other hardware description language intellectual property technology libraries. It implements the optimal mix of sub-buses, switches, sockets, and controllers that will be needed for a particular user application.

Simultaneous multithreading-based routers

Abstract: This work considers the use of an SMT (simultaneous multithreading) processor in lieu of the conventional processor(s) in a router and evaluates quantitatively the potential gains as a result. An SMT processor exploits the benefits of both ILP (instruction level parallelism) and TLP (thread-level parallelism), suitable for the next generation routers, in which an increased number of functions are to be implemented. The use of an SMT processor not only allows router functions to be decomposed into multiple threads but also designates separate threads to handle different incoming traffic streams of a router to exploit TLP, potentially attaining performance improvement. Additionally, an SMT processor may admit new router functions or added traffic streams relatively easily without compromising much existing performance levels, via including a new thread (or threads) to perform one newly added function or traffic stream. This router design appears to have better flexibility and adaptability. In order to assess the benefits of this design approach, we implemented three key router functions (i.e., packet header extraction, packet header manipulation, and longest-prefix matching) as threads using an SMT simulator (SMTSIM) for performance evaluation. The results of this router design approach are collected and compared with those of conventional routers.

Router uses a single hierarchy independent routing table that includes a flag to look-up a series of next hop routers for routing packets

Abstract: In a network processor-based device, there is provided a single routing table for network routers and an efficient routing algorithm implemented by the routing device The routing table includes packet forwarding information including a subnet address associated with a destination address location, an ISO layer three ( 3 ) network protocol address, eg, IP address, of a router interface that can route packets to the subnet address, and an identifier indicating whether that router is an exit BGP router that may or may not be directly attached to the packet forwarding router A table look-up mechanism is provided to determine next hop information and determine associated BGP status of the next hop At such time it is determined that a router is not a BGP router (ie, is directly attached to the forwarding router), the packet will be transmitted to that router

Method and system for communication

Abstract: Method for auto-configuration of a new router when added to an IP intranetwork, the IP intranetwork formed by routers interconnected via point-to-point links. The method includes the steps of 1) establishing a physical connection between the new router and an existing router within the intranetwork; 2) establishing a point-to-point link between the new router and the existing router, over the physical connection; 3) requesting and retrieving an IP address to make IP communication possible between the new router and the existing router the point-to-point link; 4) automatically identifying the resources which are essential for retrieving configuration information for the new router; 5) automatically configuring the new node by means of the configuration information; and 6) starting a routing protocol to establish network connectivity between the new router and the rest of the intranetwork.

Routing processing and method for home bus system

Abstract: In a home bus system in which a multiplicity of networks each having a multiplicity of appliances connected thereto are connected one another, information is easily exchanged between appliances over different networks. An address configuration that is processed in application software and communication middleware has a network ID and a network appliance ID. On each network, there is provided a particular router having information about all the connections of other networks than the each network. Under this configuration, an appliance transmits a message directed to another network, only to a particular router and the particular router establishes an appropriate route for transmission, as considering the actual states of the networks.

Detecting if a secure link is alive

Abstract: A communication system includes a data network that is coupled to various nodes, including routers. In one example arrangement, a first router is part of a first local network and a second router is part of a second local network. Each router includes a security gateway module and a keep-alive module. The security gateway module is capable of establishing a secure link, such as one according to an Internet Protocol Security (IPsec) protocol, over the data network. The keep-alive module sends one or more ping messages over the secure link to the remote router (or a node coupled to the router), which responds with appropriate ping replies to indicate that a link is alive.

Lightwave network data communications system

Abstract: A lightwave network data communications system having such an architecture that routing operation within a lightwave network is simplified, and a high-speed transfer process is attained in a large-scale basic network utilizing a wavelength division multiplexing (WDM) technology which accommodates internet traffics from a plurality of subscriber networks. The lightwave network data communications system includes a unit for giving a lightwave router address to an edge router and a core router in the lightwave network, a unit for resolving a destination lightwave router address and an aggregated flow identifier about an IP packet received from a subscriber, and encapsulating the IP packet into a lightwave adaptation frame with these pieces of data contained in header information in the edge router, a unit for encapsulating a plurality of packets each having a length under a fixed length into a superframe, a unit for executing a share-ride scheme in which the packets of a plurality of IP flows can be shared as a superframe, and a unit for monitoring the traffic on the superframe basis and regulating an excessive traffic.

System and method for dynamically assigning routers to hosts through a mediator

Abstract: A method and system are disclosed for dynamically assigning, on a Local Area Network, through a mediator, a plurality of active routers to a plurality of hosts so as to handle hosts data packets destined to remote users not connected on the LAN. Because hosts know only the address of the mediator they must first go through it for being assigned a particular router. When receiving the first request, mediator selects one router among those of the routers that are active and informs the host which may then forward the first packet and all subsequent ones to the selected router. The same is done for each host connected on the LAN. After which mediator is free to reassess the router to host assignment any time if significant changes are observed such as the failure of a router, the removing or the addition of a router to the pool of routers or a drastic modification of the host generated traffic.

A programmable router architecture supporting control plane extensibility

Abstract: The Internet is evolving from an infrastructure that provides basic communication services into a more sophisticated infrastructure that supports a wide range of electronic services such as virtual reality games and rich multimedia retrieval services. However, this evolution is happening only slowly, in part because the communication infrastructure is too rigid. In this article we present a programmable router architecture in which the control plane functionality of the router can be extended dynamically through the use of delegates. Delegates can control the behavior of the router through a well-defined control interface, allowing service providers and third-party software vendors to implement customized traffic control policies or protocols. We describe Darwin, a system that implements such an architecture. We emphasize the runtime environment the system provides for delegate execution and the programming interface the system exports to support delegates. We demonstrate the advantages of using this system with two delegate examples.

Scalable IP edge router

Abstract: In a data communications network, an edge router comprises a buffer for storing data packets, one or more line interface cards for routing data packets to and from the data communications network, and a processing engine for processing a limited portion of each packet that has been captured by an associated line interface card in a packet tag. The processing engine includes one or more pipeline processing modules (PPMs) which may be dynamically configured by a system controller to perform specific processing functions in a pipelined arrangement. In order to increase edge router throughput, each packet tag is processed by the processing engine essentially in parallel with storage of the associated data packet in the buffer by the associated line interface card.

Publishing node information

Abstract: The invention can enable routers in a region to share information about nodes on foreign sub-networks. The information includes the nodes' and routers' respective network layer addresses. Upon receiving a message addressed to one of the nodes, a router can tunnel the message to a router on the node's foreign sub-network for subsequent de-tunneling and delivery to the node.

Asymmetric wdm packet-switched router architecture and method for generating same

Abstract: A preferred WDM all-optical packet-switched router architecture and an integrated analysis method for determining said architecture are disclosed The method of the present invention includes the steps of simulating, with a network simulator, the operation of a desired network topology having at least one baseline router, establishing a steady state in the network simulation, applying a router and network dimensioning algrorithm to the desired network topology for a predetermined number of clock cycles, and determining the preferred network router architecture based on the predetermined number of clock cycles The baseline router used in the method of this invention can be a WDM all-optical packet-switched router, and the preferred network router architecture can be a WDM all-optical packet-switched router architecture with or without shared buffers One embodiment of the preferred WDM router archtitecture of this invention can be an asymmetric WDM router with a wavelength conversion module having a plurality of wavelength converters and shared output buffering

Method for delivery of narrow-cast data over digital broadcast channels

Abstract: Broadband multimedia system comprising a communication bus, a broad band multimedia router, connected to the communication bus, to a data router and further between a plurality of media sources and a plurality of network transmitters, a session manager, connected to communication bus, the session manager providing routing instructions to the router, for directing media received from the media sources to the network transmitters for transmitting over a broadband network and for directing data received from the router to at least a selected one of the network transmitter for transmitting over the broadband network to a specific destination.

Extending router functionality to report static group membership

Abstract: A router is configured with a static membership to a multicast group address and is capable of transmitting a message reporting the static membership to another router.

Label switched traffic routing and signaling in a label switched communication packet network

Abstract: Label switched paths are installed in a label switched communications packet network Paths are selected by defining and installing partial routes each having two or more paths such that an end-to-end route across the network can be defined as the concatenation of two partial routes Signalling to select a path is effected by sending a path message from an end point to a first virtual router, determining a path from the end point to the virtual router, and forwarding an identity of the path to a second virtual router The second virtual router determines a routing vector across the network, and returns information identifying the routing vector to the first virtual router