Showing papers on "Core router published in 2007"

A 4.6Tbits/s 3.6GHz single-cycle NoC router with a novel switch allocator in 65nm CMOS

Abstract: As chip multiprocessors (CMPs) become the only viable way to scale up and utilize the abundant transistors made available in current microprocessors, the design of on-chip networks is becoming critically important. These networks face unique design constraints and are required to provide extremely fast and high bandwidth communication, yet meet tight power and area budgets. In this paper, we present a detailed design of our on-chip network router targeted at a 36-core shared-memory CMP system in 65 nm technology. Our design targets an aggressive clock frequency of 3.6 GHz, thus posing tough design challenges that led to several unique circuit and microarchitectural innovations and design choices, including a novel high throughput and low latency switch allocation mechanism, a non-speculative single-cycle router pipeline which uses advanced bundles to remove control setup overhead, a low-complexity virtual channel allocator and a dynamically-managed shared buffer design which uses prefetching to minimize critical path delay. Our router takes up 1.19 mm2 area and expends 551 mW power at 10% activity, delivering a single-cycle no-load latency at 3.6 GHz clock frequency while achieving apeak switching data rate in excess of 4.6 Tbits/sper router node.

Ims diameter router with load balancing

Abstract: A Diameter router (20) is presented for performing load balancing and initial Diameter message routing in an IMS network, where clients in network elements (10) are provisioned with the address of the router and send an initial Diameter request message (41) for a given session to the router. The router selects a server (31) based at least partially on a type of IMS message session, application services, subscriber information, or billing information, and sends a relayed initial Diameter request message (42) to the selected server. The selected server sends an initial Diameter response (43) to the router which then forwards a relayed initial response (44) to the client. Thereafter, the client and the selected server send messages directly to each other for the remainder of the session.

Ethernet performance monitoring

Abstract: One embodiment is a source router that monitors the performance of an Ethernet network. The source router generates an Ethernet connectivity check request frame that includes a transmission timestamp, and transmits the Ethernet connectivity check request frame to a destination router. The source router receives a reply from the destination router that is transmitted in response to receiving the Ethernet connectivity check request frame and determines a round trip time between the source router and the destination router based on a time of receipt of the reply and the transmission timestamp.

A Power and Energy Exploration of Network-on-Chip Architectures

Abstract: In this study, we analyse the move towards networks-on-chips from an energy perspective by accurately modelling a circuit-switched router, a wormhole router and a speculative virtual-channel router in a 90nm CMOS process. All the routers are shown to dissipate significant idle state power. The additional energy required to route a packet through the router is then shown to be dominated by the data-path. This leads to the key result that, if this trend continues, the energy cost of more elaborate control would not be vast, making it easier to justify. Given effective clock-gating, this additional energy is also shown to be more or less independent of network congestion. Accurate speed and area metrics are also reported for the networks, which would allow a more complete comparison to be made across the NoC architectural space considered

Rotary router: an efficient architecture for CMP interconnection networks

Abstract: The trend towards increasing the number of processor cores and cache capacity in future Chip-Multiprocessors (CMPs), will require scalable packet-switched interconnection networks adapted to the restrictions imposed by the CMP environment. This paper presents an innovative router design, which successfully addresses CMP cost/performance constraints. The router structure is based on two independent rings, which force packets to circulate either clockwise or anti-clockwise, traveling through every port of the router. It uses a completely decentralized scheduling scheme, which allows the design to: (1) take advantage of wide links, (2) reduce Head of Line blocking, (3) use adaptive routing, (4) be topology agnostic, (5) scale with network degree, and (6) have reasonable power consumption and implementation cost. A thorough comparative performance analysis against competitive conventional routers shows an advantage for our proposal of up to 50 % in terms of raw performance and nearly 60 % in terms of energy-delay product.

Method of operating a network

Abstract: An Internet Protocol router device (10) for use in a data network comprising a plurality of nodes (10, 20, 30), wherein packets of data are sent from one node in the network to another on a hop by hop basis. The router includes: a data store (14) for storing a routing table indicating the next hop destination for a received packet on the basis of the ultimate destination specified by the received packet; a digital processor (13) operable to maintain the routing table on the basis of communications received from neighbouring router devices (20, 30) within the network; and a timer (15) for timing the length of time elapsed since last receiving a communication, or a communication of a type which is one of a subset of the possible types of communication, from each of one or more of the router device's neighbours; wherein the data store (14) is further operable to store in respect of each of said one or more of the router device's neighbours a router dead interval; and the digital processor (13) is further operable to compare said length of time elapsed with the corresponding router dead interval in respect of each of said one or more of the router device's neighbours and to ascertain that the corresponding router device is no longer operating correctly if the comparison indicates that a length of time equal to or greater than the router dead interval has elapsed without receiving a said communication, or a said communication of a type which is one of a subset of the possible types of communication, from said neighbouring router device; the router device being characterised in that the digital processor (13) is further operable to dynamically vary the or each router dead interval in accordance with one or more properties of the network.

Method and apparatus to establish routes based on the trust scores of routers within an ip routing domain

Abstract: A router includes a management module and a routing module. The routing module can be used to route data around a network. The management module can be used to manage the operation of the routing module, including generating an integrity report for the router, which can be used to generate a trust report for the router. The trust report can include an integrity/trust score for the router. The management module can control the routing module via a secure control interface.

System and method for managing radio frequency windows

Abstract: A system for managing radio frequency windows including a wireless router in communication with the wireless device for transmitting and receiving RF signals between the wireless router and the wireless device, the wireless router configured to determine network performance information of the wireless network; concatenate the network performance information into data packets; a packet network switch in communication with the wireless router for communicating the data packets between the wireless router and the packet network switch; and a network management device in communication with the packet network switch for instructing wireless router to adjust RF modulation between the wireless router and the wireless device based on the network performance information to optimize the network performance to the wireless device. A method for managing radio frequency windows is also included.

Linux Software Router: Data Plane Optimization and Performance Evaluation

Abstract: Recent technological advances give a good chance to reach really effective results in the field of open Internet equipments, also called Open Routers (ORs). Some initiatives have been activated since the last few years to investigate the OR and related issues. But despite these activities, large interesting areas still require a deeper investigation. This work tries to give a contribution by reporting the results of an in-depth activity of optimization and testing realized on a PC Open Router architecture based on Linux software and COTS hardware. The main target of this paper has been the forwarding performance evaluation of different OR Linux-based software architectures. This analysis has been performed with both external (throughput and latencies) and internal (profiling) measurements. In particular, for what concerns the external measurements, a set of RFC2544 compliant tests has been proposed and analyzed.

Wireless Public Network Access

Abstract: Public access to a network is provided through wireless access points, which may simultaneously support secured network access; in preferred embodiments, the access points are routers (such as “WiFi” routers). Accordingly, a router is configured with a public access profile (or profiles), which may be selectively enabled or disabled. When enabled, the router sends out an identifier that can be used to associate a client device with a public (i.e., unauthenticated) access path through the router to a network. The router also sends out a conventional identifier that can be used to associate another client device with a secured (i.e., authenticated) access path through the router, where the public and secured access paths are usable simultaneously by clients of the router.

A 5.1GHz 0.34mm 2 Router for Network-on-Chip Applications

Abstract: A five-port two-lane pipelined packet-switched router core with phase-tolerant mesochronous links forms the key communication fabric for an 80-tile network-on-chip (NoC) architecture. The 15FO4 design combines 102 GB/s of raw bandwidth with low fall-through latency of 980 ps. A shared crossbar architecture with a double-pumped crossbar switch enables a compact 0.34 mm2 router layout. In a 65nm eight-metal CMOS process, the router contains 210K transistors and operates at 5.1GHz at 1.2 V, while dissipating 945 mW.

A tree based wireless mesh for an ospf network with intra-tree communication optimization

Abstract: A system for providing a tree topology for a network having an interior gateway protocol. A first router receives a hello message (305) from all connected routers in the network. The hello messages include tree topology information (310). The first router then uses the tree topology information to determine a parent of the router (315). The first router then establishes connections with directly connected routes at the same level in the tree topology. The first router also generates link messages that include all of the prefixes for children of the first router and broadcasts the link messages.

Autoconfigured prefix delegation based on distributed hash

Abstract: In one embodiment, a method comprises detecting, by a router, an unsolicited first router advertisement message from an attachment router that provides an attachment link used by the router, the first router advertisement message specifying a first IPv6 address prefix owned by the attachment router and usable for address autoconfiguration on the attachment link; detecting, by the router, an unsolicited delegated IPv6 address prefix from the attachment router and that is available for use by the router; and automatically selecting by the router a second IPv6 address prefix based on concatenating a suffix to the delegated IPv6 address prefix, including dynamically generating the suffix based on a prescribed distributed hash operation executed by the router, the second IPv6 address prefix for use on at least one ingress link of the router.

Prefix and IP address management scheme for router and host in network system

Abstract: In a network system formed by one or a plurality of hosts having a function for accessing Internet, and a router for connecting each host and the Internet through an accessing communication path of a provider, two types of IP address including first type IP addresses and second type IP addresses are generated and selectively used by each host, according to two types of prefix including first type prefixes and second type prefixes that have shorter valid periods than the first type prefixes, which are advertised from the router periodically.

Extensions to IPv6 neighbor discovery protocol for automated prefix delegation

Abstract: In one embodiment, a method comprises detecting, by a router, a first router advertisement message from an attachment router that provides an attachment link used by the router, the first router advertisement message specifying a first IPv6 address prefix owned by the attachment router and usable for address autoconfiguration on the attachment link. The router detects an unsolicited delegated IPv6 address prefix from the attachment router and that is available for use by the router. The router claims a second IPv6 address prefix from at least a portion of the delegated IPv6 address prefix, for use on at least one ingress link of the router.

QNoC Asynchronous Router with Dynamic Virtual Channel Allocation

Abstract: An asynchronous router for quality-of service NoC is presented. It combines multiple service levels (SL) with multiple equal-priority virtual channels (VC) within each level. The VCs are assigned dynamically per each link A different number of VCs may be assigned to each SL and per each link The router employs fast arbitration schemes to minimize latency

Method for reconfiguring a router

Abstract: In a system which includes a configurable router which is configurable both as an edge router and a hub/backbone router and also including a router special needs agent (RSNA), a method which includes performing the steps of turning on active CoS/QoS provisioning between the configurable router and the RSNA such that the RSNA provides active cost of service (CoS)/quality of service (QoS) provisioning for packets entering the configurable router and such that the configurable router operates in an edge router mode and turning off (CoS)/quality of service (QoS) provisioning by the RSNA such that the configurable router operates in a hub/backbone router mode.

Pseudo wires for mobility management

Abstract: Embodiments describe mobility management utilizing neighbor discovery and at least two pseudo wires. When a wireless device desires to handoff to a detected access router, such handoff may not be configured until such time as a current access router receives routing information of the target access router. In order to minimize handoff time, communication between the target access router and the wireless device can be through the current access router utilizing least two pseudo wires. Bidirectional neighbor discovery and create is conducted by the access routers allow subsequent wireless devices to automatically handoff between the access routers.

Mobile router that monitors links

Abstract: A mobile router having a link monitor module is disclosed. The mobile router may be installed in a mobile vehicle and permit a local end-user to access wide area networks (e.g., the Internet) via the mobile router. The link monitor module may monitor the layer 2 and layer 3 links of the mobile router. When an interruption in one or more of the links is detected, the link monitor module may initiate corrective action to re-establish the link. That way, the interruption to the local end-user is minimized.

Subscription aggregation and load balancing in a broadband router

Abstract: In one embodiment, a bandwidth aggregation router is provided including a wireless broadband modem interface for communicating with a wireless network, a wired wide area network interface, and a processor configured to aggregate bandwidth from the wireless broadband modem interface and the wired wide area network interface. The router may then efficiently allocate the aggregated bandwidth to at least one device for access to a network.

Routing operations using sensor data

Abstract: In one embodiment, a method comprises an Internet Protocol (IP) router receiving sensor data from at least one of a second IP router or an attached host sensor node, the sensor data distinct from link data of a network link; the IP router generating sensor information based on storing the sensor data with metadata describing reception of the sensor data by the IP router in a routing information base; and the IP router executing a routing operation based on the sensor information stored in the routing information base.

Using Internet nodes and routers onboard satellites

Abstract: An Internet router was integrated into the UK-DMC remote-sensing satellite as a secondary experimental payload. This commercial product has been orbiting in space for over three years. We describe the integration of the router and satellite and the successful on-orbit testing of the router, which took place using the Virtual Mission Operations Center (VMOC) application as part of a larger systems internetworking exercise. Placing this Cisco router in Low Earth Orbit (CLEO) onboard a small satellite is one step towards extending the terrestrial networking model to the near-Earth space environment as part of a merged space-ground architecture.

The UMTS base station router

Abstract: This paper reviews the Alcatel-Lucent Universal Mobile Telecommunications System (UMTS) base station router (BSR)—a radio access network (RAN) and core network (CN) in a single network element. While typical cellular UMTS networks are built from a plethora of network elements and are maintained in a hierarchical fashion, the BSR combines all functions of a radio access network and core network in a single network element. Moreover, the BSR can be considered a wireless edge router that bridges between cellular-specific wireless transmissions and IP networks. Integrating RAN functionality in a single network element presents the following technical advantages: improving the responsiveness (i.e., latency reductions), reducing the complexity, and improving the fault tolerance of the system. © 2007 Alcatel-Lucent.

Multistage Switching Architectures for Software Routers

Abstract: Software routers based on personal computer (PC) architectures are becoming an important alternative to proprietary and expensive network devices. However, software routers suffer from many limitations of the PC architecture, including, among others, limited bus and central processing unit (CPU) bandwidth, high memory access latency, limited scalability in terms of number of network interface cards, and lack of resilience mechanisms. Multistage PC-based architectures can be an interesting alternative since they permit us to i) increase the performance of single- software routers, ii) scale router size, iii) distribute packet-manipulation and control functionality, iv) recover from single-component failures, and v) incrementally upgrade router performance. We propose a specific multistage architecture, exploiting PC-based routers as switching elements, to build a high-speed, large-size, scalable, and reliable software router. A small-scale prototype of the multistage router is currently up and running in our labs, and performance evaluation is under way.

Joining tree-based networks into an autonomous system using peer connections between the tree-based networks

Abstract: In one embodiment, a first router attaches to an attachment router based on detecting a first router advertisement message specifying an attachment prefix and a first tree information option. The first tree information option includes a first IP host address of a first clusterhead having established a first tree topology. The first router receives a second advertisement from a second router specifying a second address prefix, distinct from the attachment prefix and the first address prefix of the first router, and a second tree information option specifying a second IP host address of a second clusterhead having established a second distinct tree topology. If the first and second routers are at equal depths relative to the respective first and second clusterheads, routing information is shared, including first address prefix reachable via the first router, and a host route for reaching the first IP host address via the first router.

PowerTrust: A Robust and Scalable Reputation System for Trusted Peer-to-Peer Computing

Abstract: We propose a new fair scheduling technique, called OCGRR (output controlled grant-based round robin), for the support of DiffServ traffic in a core router. We define a stream to be the same-class packets from a given immediate upstream router destined to an output port of the core router. At each output port, streams may be isolated in separate buffers before being scheduled in a frame. The sequence of traffic transmission in a frame starts from higher-priority traffic and goes down to lower-priority traffic. A frame may have a number of small rounds for each class. Each stream within a class can transmit a number of packets in the frame based on its available grant, but only one packet per small round, thus reducing the intertransmission time from the same stream and achieving a smaller jitter and startup latency. The grant can be adjusted in a way to prevent the starvation of lower priority classes. We also verify and demonstrate the good performance of our scheduler by simulation and comparison with other algorithms in terms of queuing delay, jitter, and start-up latency

Secure neighbor discovery router for defending host nodes from rogue routers

Abstract: In one embodiment, a method comprises receiving, by a router in a network, a router advertisement message on a network link of the network; detecting within the router advertisement message, by the router, an advertised address prefix and an identified router having transmitted the router advertisement message within the network; determining, by the router, whether the identified router is authorized to at least one of advertise itself as a router, or advertise the advertised address prefix on the network link; and selectively initiating, by the router, a defensive operation against the identified router based on the router determining the identified router is not authorized to advertise itself as a router, or advertise the advertised address prefix on the network link.

Preconfiguring IP-over-Optical Networks to Handle Router Failures and Unpredictable Traffic

Abstract: We consider the realization of traffic-oblivious routing in IP-over-optical networks where routers are interconnected over a switched optical backbone. The traffic-oblivious routing we consider is a scheme where incoming traffic is first distributed in a preset manner to a set of intermediate nodes. The traffic is then routed from the intermediate nodes to the final destination. This splitting of the routing into two phases simplifies network configuration significantly. In implementing this scheme, the first and second phase paths are realized at the optical layer with router packet grooming at a single intermediate node only. Given this unreliability of routers, we consider how two-phase routing in IP-over-optical networks can be made resilient against router node failures. We propose two different schemes for provisioning the optical layer to handle router node failures-one that is failure node independent and static, and the other that is failure node dependent and dynamic We develop linear programming formulations for both schemes and a fast combinatorial algorithm for the second scheme so as to maximize network throughput. In each case, we determine (i) the optimal distribution of traffic to various intermediate routers for both normal (no-failure) and failure conditions, and (ii) provisioning of optical layer circuits to provide the needed inter-router links. We evaluate the performance of the two router failure protection schemes and compare it with that of unprotected routing

Rerouting for double-link failure recovery in an internet protocol network

Abstract: A router in a survivable portion of a network may forward packets to a destination node even in the event of a double-link failure. For a given destination node, the router has previously been configured with a primary port, a primary backup port, and a secondary backup port. The router receives a packet addressed to the destination node within the survivable portion of the network, wherein the packet includes information indicating that the packet has encountered a failure. The router then selects one of (A) the primary port, (B) the primary backup port and (C) the secondary backup port on which to forward the received packet, such that a backup path with no dead loops is defined. The router may obtain a recovery distance of at least one of (A) the primary backup port based on a backup path to which it leads, and (B) the secondary backup port based on a backup path to which it leads, and may further obtain counter information in a packet indicative of a failure distance. In this case, the router may select a port whose recovery distance is greater than the failure distance. The router may identify a pattern of the failure. In this case, the router may make its selection using a forwarding policy associated with the identified pattern.