Showing papers on "Core router published in 2003"

Trade Offs in the Design of a Router with Both Guaranteed and Best-Effort Services for Networks on Chip

Abstract: Managing the complexity of designing chips containing billions of transistors requires decoupling computation from communication. For the communication, scalable and compositional interconnects, such as networks on chip (NoC) must be used. In this paper, we show that guaranteed services are essential in achieving this decoupling. Guarantees typically come at the cost of lower resource utilization. To avoid this, they must be used in combination with best-effort services. The key element of our NoC is a router consisting conceptually of two parts: the so-called guaranteed throughput (GT) and best-effort (BE) routers. We combine the GT and BE router architectures in an efficient implementation by sharing resources. We show the trade offs between hardware complexity and efficiency of the combined router, and the motivation of our choices. Our reasoning for the trade offs is validated with a prototype router implementation. We show a lay-out of an input-queued wormhole 5/spl times/5 router with an aggregate bandwidth of 80 Gbit/s. It occupies 0.26 mm/sup 2/ in CMOS12. This shows that our router provides high performance at reasonable cost, bringing NoCs one step closer.

Candidate access router discovery

Abstract: An arrangement and a method is provided for discovering candidate access routers in a mobile IP (Internet Protocol) network to enable seamless IP handover of a mobile node between access routers. A server element (19), which is separate from the access routers (11, 12) and the mobile node (MN), is provided with access router information relating to one or more access routers and with information identifying the access router serving the mobile node and reachability information about one or more access routers other than the serving access router that are within reach to the mobile node. The address of at least one of said one or more access routers within reach to the mobile node is determined in the server element on the basis of the provided information.

Arrangement for router attachments between roaming mobile routers in a mobile network

Abstract: A mobile router is configured for attaching to a selected router in a mobile network based on identifying a network topology model of the mobile network from received router advertisement messages that include tree information option fields specifying attributes of the network topology model. The mobile router selects which router advertisement originator to attach to based on correlating the attributes of the router advertisement originators relative to identified priorities, and orders the router advertisement originators within a default router list based on the identified priorities. The mobile router attaches to one of the routers in the ordered default router list having a higher priority, and upon attaching to the router advertisement originator as its attachment router, the mobile router transmits its own corresponding router advertisement message including a corresponding tree option field that specifies the attributes of the mobile router within the network topology model, enabling other routers to selectively connect and/or reconnect within the mobile network based on their respective identified preferences.

Caching with selective multicasting in a publish-subscribe network

Abstract: Packet routing via payload inspection at routers in a core of a distributed network. Packets include subjects and attributes in addition to routing information. The subjects correspond with particular types of content for subscriptions, and the attributes encapsulate the data or content. The routers store filters corresponding with subscriptions to content. Upon receiving a packet, a router inspects the payload section of the packet containing the attributes in order to retrieve the attributes and apply them to the filters for the subscriptions. If an attribute satisfies a filter, the packet is routed to the next link. If the attributes do not satisfy the filters, the router discards the packet. These routing decisions are distributed among routers in the network core. The router locally caches the data in the network core.

Methods and apparatus for determining the port and/or physical location of an ip device and for using that information

Abstract: Methods and apparatus for providing location and other customer information corresponding to an IP addresses, including dynamically assigned IP address, are described. A port of an edge router is assigned to serve as a customer's point of access to an IP based network. Customer information including the location of the customer premises from which the IP network is accessed through the assigned edge router port is stored in a database associating edge router and port information with customer information. When information about a customer using an IP address is desired a database associating IP addresses with edge routers, e.g., edge which acted as proxies to facilitate IP address leasing is consulted. The edge router corresponding to the IP address of interest is then contacted to determine the port number associated with the IP address. Recovered edge router and port number information is then used to access the customer information database.

Method and apparatus for distributing routing instructions over multiple interfaces of a data router

Abstract: A software application in a multi-processor data router (703, 705, 707, 708, 710, 711) in which a forwarding information base for the router (703, 705, 707, 708, 710, 711) is maintained is provided with a server module and one or more client modules, each client module associated with one or more communication interfaces of the data router (703, 705, 707, 708, 710, 711) . The application is characterized in that the server module sends to each client module only that portion of the forwarding information base specific to the communication interfaces associated with the client module.

Arrangement in a router of a mobile network for optimizing use of messages carrying reverse routing headers

Abstract: A mobile router is configured for optimized utilization of reverse routing headers, to specify a path between an originating mobile router and a home agent. Reverse routing headers enable each mobile router within the path to the home agent to specify its care of address, enabling the home agent to establish a bidirectional tunnel to the originating mobile router via the corresponding mobile router. The mobile router selectively updates the reverse routing header in a received packet by inserting the source address value of the received packet into the reverse routing header and inserting its corresponding care of address into the source address field, based on whether the mobile router lacks a routing table entry that specifies reachability of a most recent entry in the reverse routing header via the source address value. The mobile router also may request the originating mobile router to increase the reverse routing header size.

Satellite receiver/router, system, and method of use

Abstract: This specification discloses a satellite transmission system for transmission of TCP/IP compatible packets from a head end computer through a satellite uplink, an extraterrestrial satellite, a satellite downlink, and an integrated satellite receiver/router for outputting of the TCP/IP compatible packets through a port on the receiver/router onto a computer LAN or WAN. The system may include an Internet or telecommunications backchannel. The receiver becomes router enabled by means of a removable insertion Ethernet/Router insertion card inserted into a slot in the receiver, although the transmission system may be used to simultaneously transmit a variety of other services through the receiver by use of other service slots in the receiver. The Ethernet/Receiver supports the IGMPv2 Multicasting (querier and non querier modes), standard TCP/IP (including UDP and Telnet), and SNMP protocols.

Method and system for router redundancy in a wide area network

Abstract: A method for selecting an active router in a communication device includes providing multiple routers in the device, coupling the routers to a single physical link, monitoring a status for each of the routers, and selecting one of the routers as an active router by positioning its corresponding relay.

Method and system for supporting a dedicated label switched path for a virtual private network over a label switched communication network

Abstract: A system and method for transmitting data from a first site to a second site over a shared Multi-Protocol Label Switched (MPLS) network comprising a plurality of routers, including an ingress router in communication with the first site and an egress router in communication with the second site, includes configuring a plurality of label switching paths between the ingress router and the egress router over a plurality of label switching devices. The method further includes performing a first lookup on one of at least one virtual routing and forwarding (VRF) table stored in the ingress router, whereby the first lookup identifies one routing table from a plurality of routing tables stored in the ingress router, each routing table being associated with one of the plurality of label switched paths, and performing a second lookup on the one routing table, wherein the routing table defines the associated label switched path between the ingress router and the egress router for a virtual private network (VPN) between the first site and the second site.

Provisioning seamless applications in mobile terminals through registering and transferring of application context

Abstract: Service provisioning in mobile terminals is provided through registering and transferring of application context, which permits substantially seamless transfer of application functionality across administrative service domains. An architecture for providing application context transfer may include access routers, transcoder proxy servers, and gateway routers. A mobile terminal served by a current access router creates an application context for a session and registers it with the current access router. Around the time of handoff, the current access router transfers the application context to a new access router associated with a new administrative domain and a new access network. The new access router evaluates the application context and takes steps to provide application functionality for the mobile terminal and current sessions. These steps may include the use of a network entity, such as a transcoder proxy server, to modify data for a session and thereby provide application functionalitY in the new administrative domain.

Mesh networks with exclusion capability

Abstract: In an exemplary method implementation, a method includes: designating a neighborhood administrator; receiving notification of a delinquent router from the designated neighborhood administrator; and excluding the delinquent router responsive to the notification. In an exemplary mesh router implementation, a mesh router is capable of establishing a wireless mesh network with other mesh routers, the mesh router is further capable of designating a neighborhood administrator mesh router; and the mesh router is adapted to exclude another mesh router that is associated with a particular certificate when the particular certificate has been identified as delinquent by the designated neighborhood administrator. mesh router.

End-to-end contention resolution schemes for an optical packet switching network with enhanced edge routers

Abstract: This paper investigates contention resolution schemes for optical packet switching networks from an end-to-end perspective, where the combined exploitation of both core routers and edge routers are highlighted. For the optical-core network, we present the architecture of an optical router to achieve contention resolution in wavelength, time, and space domains. Complementing the solution involving only the core router intelligences, we propose performance enhancement schemes at the network edge, including a traffic-shaping function at the ingress edge and a proper dimensioning of the drop port number at the egress edge. Both schemes prove effective in reducing networkwide packet-loss rates. In particular, scalability performance simulations demonstrate that a considerably low packet-loss rate (0.0001% at load 0.6) is achieved in a 16-wavelength network by incorporating the performance enhancement schemes at the edge with the contention resolution schemes in the core. Further, we develop an field-programmable gate-array (FPGA)-based switch controller and integrate it with enabling optical devices to demonstrate the packet-by-packet contention resolution. Proof-of-principle experiments involving the prototype core router achieve an error-free low-latency contention resolution.

Method and system for fast IP connectivity in a mobile network

Abstract: An apparatus, system, and method are directed to managing connec tivity in a network by expediting the ability of a mobile node to send Internet Protocol (IP) packets subsequent to a handover. The mobile node is configured to determine an unconfirmed address for use on an access router. Upon establishing a link-layer connection, and before establishing a network-layer connection with the access router, the mobile node employs the unconfirmed address to send an IP packet to the access router. Employing the unconfirmed address prior to network-layer connectivity enables the reduction of handover latencies. If the access router determines that the unconfirmed address conflicts with an existing address, the access router provides a message to the mobile node indicating the conflict in addresses. In response to the message, the mobile node performs actions to resolve the address conflict.

Mobile communication device, mobile router, and mobile communication system

Abstract: Provided are a service-type recording section for recording a characteristic of a service to be utilized by the mobile communication device and an interface recording section for recording an externally-connecting interface type of within a network and a characteristic thereof. The interface decision section selects at least one or more of interfaces satisfying a service request and notifies it to a mobile router possessing an externally-connecting interface. Due to this, in case there is a link status change in the external interface of the mobile router, the mobile communication device is allowed to swiftly switch the external interface and continue communication. Moreover, congestion can be avoided from occurring in communication between the mobile communication device and the mobile router during switchover.

Request routing network system, request router apparatus, router apparatus and a method for path setting in a network

Abstract: A request routing system for offering high-quality, low-priced data delivery services to a large number of users is disclosed. Request router RR 1 for redirecting data requests to delivery servers manages the data storage in each delivery server, the MPU load on each delivery server, the delay time involved between delivery servers and terminals, and the bandwidths of data delivery paths between delivery servers and terminals. If a bandwidth required for data delivery cannot be acquired, request router RR 1 can perform a calculation to check whether an alternative path can be set between a delivery server and terminal. If the result of the calculation indicates that an alternative path can be set, request router RR 1 can explicitly set such a path.

Handover method in mobile communication system and router device used in mobile communication system

Abstract: An old care-of address is assigned to a mobile node in the communication area of the old access router and the mobile node is communicating with a correspondent node Immediately before the mobile node enters the communication area of a new access router, a binding update message is transmitted to a diverging point router The diverging point router is a router device located in the node where a route from the correspondent node to the old access router and a route from the correspondent router to the new access router are diverged The diverging point router transfers packets addressed to the old care-of address to the new care-of address assigned to the mobile node in the communication area of the new access router

Transport-aware IP routers: a built-in protection mechanism to counter DDoS attacks

Abstract: The lack-of service differentiation and resource isolation by current IP routers exposes their vulnerability to Distributed Denial of Service (DDoS) attacks (Garber, 2000), causing a serious threat to the availability of Internet services. Based on the concept of layer-4 service differentiation and resource isolation, where the transport-layer information is inferred from the IP headers and used for packet classification and resource management, we present a transport-aware IP (tIP) router architecture that provides fine-grained service differentiation and resource isolation among different classes of traffic aggregates. The tIP router architecture consists of a fine-grained Quality-of-Service (QoS) classifier and an adaptive weight-based resource manager. A two-stage packet-classification mechanism is devised to decouple the fine-grained QoS lookup from the usual routing lookup at core routers. The fine-grained service differentiation and resource isolation provided inside the tIP router is a powerful built-in protection mechanism to counter DDoS attacks, reducing the vulnerability of Internet to DDoS attacks. Moreover, the tIP architecture is stateless and compatible with the Differentiated Service (DiffServ) infrastructure. Thanks to its scalable QoS support for TCP control segments, the tIP router supports bidirectional differentiated services for TCP sessions.

Relocation of content sources during ip-level handoffs

Abstract: The present invention provides a relocation of content sources (111, 119) that provide media content to a mobile terminal (mobile node) (105) when a network layer-level handoff occurs. The relocation of content sources (111, 119) enables the mobile terminal (105) to seamlessly execute an application that utilizes the media content from a current content source (111) before the handoff and from a new content source (119) after the handoff. The mobile terminal (105) registers with a current access router (109) in order to inform the access router about application context information. The current access router (109) informs the new access router (117) about the impending handoff. The new access router (117) consequently discovers the new content source (119).

Packet transmission method and communication system

Abstract: The object is to prevent occurrence of packet loss in Cellular IP and a drop of TCP throughput due to duplication of packets. On the occasion of relaying a packet from correspondent, a relay router multicasts a router advertisement to access routers forming respective cells into which a target mobile terminal might move. The mobile terminal receives the router advertisements from the neighbor access routers, calculates a difference between reception times of the packets from the respective access routers, and specifies a relay router to perform multicasting. Then the mobile terminal transmits delay information of a delay to be added to each path in multicasting by the relay router, to the relay router thus specified. The relay router adds the delay to each path in multicasting on the basis of the delay information.

Software configurable cluster-based router using heterogeneous nodes as cluster nodes

Abstract: A cluster router architecture and methods for performing distributed routing are presented. The cluster router architecture includes off-the shelf Personal Computer (PC) hardware-based router cluster nodes interconnected in an intra-connection network in multiple dimensions. Each PC-based router cluster node is provided with the same routing functionality and a router-cluster-node-centric configuration enabling each router cluster node to provide routing responses for packets pending processing. Packet processing is divided into entry packet processing and routing response processing; special processing; and exit processing. Exit packet processing is performed by router cluster nodes transmitting packets into communication networks in which the cluster router participates. Packet processing is interrupted on determining that special processing is required in respect of a packet, and the packet is handed over to a corresponding special purpose router cluster node.

Method and network device for synchronization of database data routed through a router

Abstract: SyncML is used for synchronizing data of terminal device in wireless and wired environments. In general, synchronization takes place between a terminal device (e.g., a mobile phone) and a server device (e.g., a web server in Internet). However, a SyncML session, which occurs between the terminal and server, is an end-to-end communication. The idea of the present invention is to provide a method, a router and a system to allow routing of the synchronizing data exchanged during a synchronizing session through such a router. In general having the router is more cost efficient and a faster solution from the end-user point of view.

Arrangement in a router for generating a route based on a pattern of a received packet

Abstract: A router (e.g., a home agent for an IPv6 mobile router) is configured for determining a destination router (e.g., the IPv6 mobile router) for a received packet based on accessing a routing table having multiple routing entries, each routing entry including a routing key and a routing field that specifies one of a prescribed address specifying the destination router and a computation tag. The computation tag specifies a prescribed function to be executed to calculate a determined address for the destination router (e.g., the home address for the IPv6 mobile router). The router identifies, for each received packet, the matching routing entry based on the corresponding routing key, and in response to detecting the computation tag in the routing field, selectively executes the corresponding function to calculate the determined address for the destination router.

Flow control in a network environment

Abstract: Providing flow control includes receiving at a router an indication of the ability of each one of multiple ports not directly connected to the router and controlling transmission of data from the router to the multiple ports based at least on the indication.

DIRAC: a software-based wireless router system

Abstract: Routers are expected to play an important role in the IP-based wireless data network. Although a substantial number of techniques have been proposed to improve wireless network performance under dynamic wireless channel conditions and host mobility, a system support framework is still missing. In this paper, we describe DIRAC, a software-based router system that is designed for wireless networks to facilitate the implementation and evaluation of various channel-adaptive and mobility-aware protocols. DIRAC adopts a distributed architecture that is composed of two parts: a Router Core (RC) shared by the wireless subnets, and a Router Agent (RA) at each access point/base station. RAs expose wireless link-layer information to the RC and enforce the control commands issued by the RC. This approach allows the router to make adaptive decisions based on link-layer information feedback. It also permits the router to enforce its policies (e.g., policing) more effectively through underlying link-layer mechanisms. As showcases, we implement under DIRAC the prototypes of three wireless network services: link-layer assisted fast handover, channel-adaptive scheduling, and link-layer enforced policing. Our implementation and experiments show that our distributed wireless router provides a flexible framework, which enables advanced network-layer wireless services that are adaptive to channel conditions and host mobility.

Arrangement in a router of a mobile network for generating a local router prefix for anonymous route connections

Abstract: A mobile router is configured for generating a local router prefix (i.e., a null or invalid address prefix that is not reachable via a wide area network) for use by mobile nodes that attempt to attach to the mobile router. The mobile router attaches to an attachment router using a care-of address with an attachment router address prefix, and outputs a router advertisement message that specifies the null address prefix. Upon receiving a message from a mobile host that includes a source address field specifying a mobile host care-of address that includes the null address prefix, the mobile router adds the mobile host care-of address to a reverse routing header and inserts its own care-of address into the source address field. The message is output to its destination with the reverse routing header, ensuring the IPv6 address of the mobile router remains anonymous in the wide area network.

Event router and method for handling events in distributed computing applications

Abstract: The present invention is a method and system for sutomating the establishment of generator-listener communication within a distributed environment. A software module known as an event router (50) monitors objects present in the distributed environment and registers listeners (40, 42, 44) with generators (30, 32, 34) according to a set of rules established within, or accessible to, the event router (50). In one embodiment the event router registers listeners (40,42,44) with generators. In another embodiment the event router directs events to a Tuple Space.

System and method for mobile router cost metric updates for routing protocols

Abstract: A system and method is directed to updating information in a mobile network. A dynamic signaling routing protocol is extended over bi-directional tunneling between a mobile router and its home agent such that information associated with the home agent of the mobile router reflects roaming of the mobile router as it travels from its home network. The information is determined as a function of a characteristic associated with each link of the tunnel between the mobile router and its home agent. In one embodiment, the information includes a cost metric associated with the cost of the tunnel. The information is advertised to another router. The other router employs the information associated with the tunnel to determine a path for communication.

Managing resources for ip networking

Abstract: Resources for IP networking are managed. A field is added to an operating system kernel software procedure. The field references a virtual router context (1020). Packet processing software code is modified to cause the packet processing software code to execute in accordance with the virtual router context (1070).

Satellite ip multicasting system and method

Abstract: The present invention relates to a satellite IP multicasting system and method for constructing an IP multicast network by a unit of internet node having a router for subscriber connection or a switch, and for transmitting a multicasting packet transmitted from a content provider into a local IP multicast network via a satellite. The satellite IP multicasting system features a backbone network, a content provider, a satellite network and a local network. The local network, which is interworked with the backbone network, is configured to multicasting protocol at a router or a switch, performs reverse path forwarding by static multicasting routing setup on a router or a switch connected to the satellite network via Ethernet and on a subscriber router or by IP designation of the same sub-net with source address of IP header of the multicast packet to an output port of a satellite data receiver and a port of a router connected to the satellite data receiver, and transmits the multicast packet into a terminal client.