Showing papers on "Routing table published in 2014"

SDX: a software defined internet exchange

Abstract: BGP severely constrains how networks can deliver traffic over the Internet. Today's networks can only forward traffic based on the destination IP prefix, by selecting among routes offered by their immediate neighbors. We believe Software Defined Networking (SDN) could revolutionize wide-area traffic delivery, by offering direct control over packet-processing rules that match on multiple header fields and perform a variety of actions. Internet exchange points (IXPs) are a compelling place to start, given their central role in interconnecting many networks and their growing importance in bringing popular content closer to end users. To realize a Software Defined IXP (an "SDX"), we must create compelling applications, such as "application-specific peering"---where two networks peer only for (say) streaming video traffic. We also need new programming abstractions that allow participating networks to create and run these applications and a runtime that both behaves correctly when interacting with BGP and ensures that applications do not interfere with each other. Finally, we must ensure that the system scales, both in rule-table size and computational overhead. In this paper, we tackle these challenges and demonstrate the flexibility and scalability of our solutions through controlled and in-the-wild experiments. Our experiments demonstrate that our SDX implementation can implement representative policies for hundreds of participants who advertise full routing tables while achieving sub-second convergence in response to configuration changes and routing updates.

Routing Metrics of Cognitive Radio Networks: A Survey

Abstract: The majority of work in cognitive radio networks have focused on single-hop networks with mainly challenges at the physical and MAC layers. Recently, multi-hop secondary networks have gained attention as a promising design to leverage the full potential of cognitive radio networks. One of the main features of routing protocols in multi-hop networks is the routing metric used to select the best route for forwarding packets. In this paper, we survey the state-of-the-art routing metrics for cognitive radio networks. We start by listing the challenges that have to be addressed in designing a good routing metric for cognitive radio networks. We then provide a taxonomy of the different metrics and a survey of the way they have been used in different routing protocols. Then we present a case study to compare different classes of metrics. After that, we discuss how to combine individual routing metrics to obtain a global one. We end the paper with a discussion of the open issues in the design of future metrics for cognitive radio networks.

The Segment Routing Architecture

Abstract: Network operators anticipate the offering of an increasing variety of cloud-based services with stringent Service Level Agreements. Technologies currently supporting IP networks however lack the flexibility and scalability properties to realize such evolution. In this article, we present Segment Routing (SR), a new network architecture aimed at filling this gap, driven by use-cases defined by network operators. SR implements the source routing and tunneling paradigms, letting nodes steer packets over paths using a sequence of instructions (segments) placed in the packet header. As such, SR allows the implementation of routing policies without per-flow entries at intermediate routers. This paper introduces the SR architecture, describes its related ongoing standardization efforts, and reviews the main use-cases envisioned by network operators.

On the effect of forwarding table size on SDN network utilization

Abstract: Software Defined Networks (SDNs) are becoming the leading technology behind many traffic engineering solutions, both for backbone and data-center networks, since it allows a central controller to globally plan the path of the flows according to the operator’s objective. Nevertheless, networking devices’ forwarding table is a limited and expensive resource (e.g., TCAM-based switches) which should thus be considered upon configuring the network. In this paper, we concentrate on satisfying global network objectives, such as maximum flow, in environments where the size of the forwarding table in network devices is limited. We formulate this problem as an (NP-hard) optimization problem and present approximation algorithms for it. We show through extensive simulations that practical use of our algorithms (both in Data Center and backbone scenarios) result in a significant reduction (factor 3) in forwarding table size, while having a small effect on the global objective (maximum flow).

Server, router, receiving terminal, and processing method

Abstract: A server according to the present disclosure includes: a converting unit that converts content data to enhance a real-time property, and creates a packet of the converted content data; and a server control unit that updates a routing table that describes processing for an interest packet, wherein when an interest packet for content including converted content data is received, the server control unit performs control of issuing an interest packet for original content data of the content which is to be converted, and when original content data to be processed is received from a CCN, the server control unit performs control of causing the original content data to be converted, a packet of the converted original content data to be created, and the packet of the converted original content data to be transmitted as a response packet for the interest packet for the content including the converted content data.

GEDAR: Geographic and opportunistic routing protocol with Depth Adjustment for mobile underwater sensor networks

Abstract: Efficient protocols for data packet delivery in mobile underwater sensor networks (UWSNs) are crucial to the effective use of this new powerful technology for monitoring lakes, rivers, seas, and oceans. However, communication in UWSNs is a challenging task because of the characteristics of the acoustic channel. In this work, we present a feasible solution for improving the data packet delivery ratio in mobile UWSN. The GEographic and opportunistic routing with Depth Adjustment-based topology control for communication Recovery (GEDAR) over void regions uses the greedy opportunistic forwarding to route packets and to move void nodes to new depths to adjust the topology. Simulation results shown that GEDAR outperforms the baseline solutions in terms of packet delivery ratio, latency and energy per message.

Routing protocols for wireless sensor networks with mobile sinks: a survey

Abstract: Wireless sensor networks with mobile sinks, mWSNs, have attracted a lot of attention recently. This is because sink mobility can greatly alleviate the hotspot issue in WSNs and further prolong the network lifetime. However, sink mobility also causes unexpected changes in network topology and data routing paths, which can largely affect the routing performance in such networks. Design of efficient routing protocols for mWSNs has been a critical issue, and much work has been carried out in this aspect. In this article, we first classify existing protocols based on different design criteria and then present a survey of the state-of-the-art routing protocols in this area. We illustrate how each of the protocols works, and discuss their advantages and disadvantages. Finally, we point out some future directions for efficient routing in mWSNs.

TSRF: A Trust-Aware Secure Routing Framework in Wireless Sensor Networks

Abstract: In recent years, trust-aware routing protocol plays a vital role in security of wireless sensor networks (WSNs), which is one of the most popular network technologies for smart city. However, several key issues in conventional trust-aware routing protocols still remain to be solved, such as the compatibility of trust metric with QoS metrics and the control of overhead produced by trust evaluation procedure. This paper proposes a trust-aware secure routing framework (TSRF) with the characteristics of lightweight and high ability to resist various attacks. To meet the security requirements of routing protocols in WSNs, we first analyze features of common attacks on trust-aware routing schemes. Then, specific trust computation and trust derivation schemes are proposed based on analysis results. Finally, our design uses the combination of trust metric and QoS metrics as routing metrics to present an optimized routing algorithm. We show with the help of simulations that TSRF can achieve both intended security and high efficiency suitable for WSN-based networks.

TLR: A Traffic-Light-Based Intelligent Routing Strategy for NGEO Satellite IP Networks

Abstract: We present TLR, a traffic-light-based intelligent routing strategy for NGEO satellite IP networks. In TLR, a set of traffic lights are used to indicate the congestion status at both the current node and the next node. When a packet travels along a pre-calculated route to the destination, it may adjust the route dynamically, according to the real-time color of traffic lights at each intermediate node. Through the combination of preliminary planning and real-time adjustment, each packet can eventually get an approximately optimal transmission path. The multi-path routing mechanism in TLR can help achieve a good distribution of traffics when the network traffic increases. The Public Waiting Queue scheme in TLR can fully utilize free spaces of the buffer queues and lower the packet drop rate. While the concept of TLR has many advantages, it may result in endless-loop of routing. To eliminate this phenomenon, a defense scheme is incorporated in the design of TLR. A set of simulations are conducted using the Network Simulator (version 2) to verify the good performance of TLR, in terms of lower packet drop rate, better distribution of traffics and higher throughput, over the entire satellite constellation.

On the role of routing in named data networking

Abstract: A unique feature of Named Data Networking (NDN) is that its forwarding plane can detect and recover from network faults on its own, enabling each NDN router to handle network failures locally without relying on global routing convergence This new feature prompts us to re-examine the role of routing in an NDN network: does it still need a routing protocol? If so, what impact may an intelligent forwarding plane have on the design and operation of NDN routing protocols? Through analysis and extensive simulations, we show that routing protocols remain highly beneficial in an NDN network Routing disseminates initial topology and policy information as well as long-term changes in them, and computes the routing table to guide the forwarding process However, because the forwarding plane is capable of detecting and recovering from failures quickly, routing no longer needs to handle short-term churns in the network Freeing routing protocols from short-term churns can greatly improve their scalability and stability, enabling NDN to use routing protocols that were previously viewed as unsuitable for real networks

Opportunistic compression of routing segment identifier stacks

Abstract: A method and device are disclosed for opportunistic compression of routing segment identifiers. In one embodiment, the method includes participating in routing of a first data packet through a first node in a network, and subsequently entering into an arrangement with an adjacent node in the network. The first data packet includes a first plurality of routing segment identifiers, and additional data packets to be routed through the first node also include the first plurality of routing segment identifiers. The arrangement entered into includes representation of the first plurality of routing segment identifiers by a single compression identifier. The method further includes participating in routing of at least one of the additional data packets using the compression identifier instead of the first plurality of routing segment identifiers. In an embodiment, the device includes one or more network interfaces and a processor configured to perform the steps of the method.

Method and system for path monitoring using segment routing

Abstract: A method and system are disclosed for use of segment routing in monitoring of a network path. In one embodiment, the method includes selecting a plurality of segment identifiers and assembling the segment identifiers into a segment identifier stack, where the segment identifier stack encodes a test path within the network for attempted routing of a test message. The method may further include inserting the segment identifier stack into a header associated with the test message, and forwarding the test message according to an entry in a forwarding table corresponding to the segment identifier at the top of the segment identifier stack. Interior gateway protocol advertisements may be used to communicate segment identifiers for creating or updating of the data structure or the forwarding table. In an embodiment, the system includes one or more network interfaces and a processor configured to perform the steps of the method.

PSR: A Lightweight Proactive Source Routing Protocol For Mobile Ad Hoc Networks

Abstract: Opportunistic data forwarding has drawn much attention in the research community of multihop wireless networking, with most research conducted for stationary wireless networks. One of the reasons why opportunistic data forwarding has not been widely utilized in mobile ad hoc networks (MANETs) is the lack of an efficient lightweight proactive routing scheme with strong source routing capability. In this paper, we propose a lightweight proactive source routing (PSR) protocol. PSR can maintain more network topology information than distance vector (DV) routing to facilitate source routing, although it has much smaller overhead than traditional DV-based protocols [e.g., destination-sequenced DV (DSDV)], link state (LS)-based routing [e.g., optimized link state routing (OLSR)], and reactive source routing [e.g., dynamic source routing (DSR)]. Our tests using computer simulation in Network Simulator 2 (ns-2) indicate that the overhead in PSR is only a fraction of the overhead of these baseline protocols, and PSR yields similar or better data transportation performance than these baseline protocols.

Opportunistic Routing for Smart Grid With Power Line Communication Access Networks

Abstract: Power line communications (PLCs) have recently absorbed interest in the smart grid since they offer communication capability in an easy and simple deployment. The main role of PLC access network (PLC-AN), which is constructed with medium and low voltage distribution networks, is to exchange control signals between substations and end users or to provide the Internet access to homes. Since a transmission signal of narrowband PLC penetrates electronic devices, a use of opportunistic routing (OR) can be a viable option in PLC-AN design. In this paper, we investigate the feasibility of OR use in PLC-AN and propose a customized OR for it, named PLC-OR, which uses static geographical information. For doing this, we formulate a bit-meter per second maximization problem and solves it in a distributed manner. Through simulations, we confirm that our proposed PLC-OR successfully reduces packet transmission time compared to the traditional sequential routing while achieving the same level of reliability in packet delivery.

Power-Aware NoCs through Routing and Topology Reconfiguration

Abstract: With the advent of multicore processors and system-on-chip designs, intra-chip communication demands have exacerbated, leading to a growing adoption of scalable networks-on-chip (NoCs) as the interconnect fabric. Today, conventional NoC designs may consume up to 30% of the entire chip's power budget, in large part due to leakage power. In this work, we address this issue by proposing Panthre: our solution deploys power-gating to provide long intervals of uninterrupted sleep to selected units. Packets that would normally use power-gated components are steered away via topology and routing reconfiguration, while Panthre provides low-latency alternate paths to their destinations. The routing reconfiguration operates in a distributed fashion and guarantees that deadlock-free routes are available at all times. At runtime, Panthre adapts to the application's communication patterns by updating its power-gating decisions. It employs a feedback-based distributed mechanism to control the amount of sleeping components and of packets detours, so that performance degradation is kept at a minimum. Our design is flexible, providing a mechanism that designers can use to tradeoff power savings with performance, based on application's requirements.Our experiments on multi-programmed communication-light workloads from the SPEC CPU2006 suite show that Panthre reduces total network power consumption by 14.5% on average, with only a 1.8% degradation in performance, when all processor nodes are active. At times when 15-25% of the processor cores are communication-idle, Panthre enables leakage power savings of 36.9% on average, while still providing connected and deadlock-free routes for all other nodes.

A Multicast Tree Router for Multichip Neuromorphic Systems

Abstract: We present a tree router for multichip systems that guarantees deadlock-free multicast packet routing without dropping packets or restricting their length. Multicast routing is required to efficiently connect massively parallel systems' computational units when each unit is connected to thousands of others residing on multiple chips, which is the case in neuromorphic systems. Our tree router implements this one-to-many routing by branching recursively-broadcasting the packet within a specified subtree. Within this subtree, the packet is only accepted by chips that have been programmed to do so. This approach boosts throughput because memory look-ups are avoided enroute, and keeps the header compact because it only specifies the route to the subtree's root. Deadlock is avoided by routing in two phases-an upward phase and a downward phase-and by restricting branching to the downward phase. This design is the first fully implemented wormhole router with packet-branching that can never deadlock. The design's effectiveness is demonstrated in Neurogrid, a million-neuron neuromorphic system consisting of sixteen chips. Each chip has a 256 × 256 silicon-neuron array integrated with a full-custom asynchronous VLSI implementation of the router that delivers up to 1.17 G words/s across the sixteen-chip network with less than 1 μs jitter.

Transactions using temporary credential data

Abstract: A method is disclosed. The method includes receiving a credential request message requesting a temporary credential associated with a payment account, and then determining, by a server computer, using a routing table and data associated with the payment card, a third-party computer associated with the payment account. The method also includes transmitting the credential request message to the third-party computer, and receiving, by the server computer, the temporary credential from the third-party computer. The method also includes determining, by the server computer, the communication device associated with the requested temporary credential and transmitting, by the server computer, the temporary credential to the communication device.

Hypercube-Based Multipath Social Feature Routing in Human Contact Networks

Abstract: Most routing protocols for delay tolerant networks resort to the sufficient state information, including trajectory and contact information, to ensure routing efficiency. However, state information tends to be dynamic and hard to obtain without a global and/or long-term collection process. In this paper, we use the internal social features of each node in the network to perform the routing process. In this way, feature-based routing converts a routing problem in a highly mobile and unstructured contact space to a static and structured feature space. This approach is motivated from several human contact networks, such as the Infocom 2006 trace and MIT reality mining data, where people contact each other more frequently if they have more social features in common. Our approach includes two unique processes: social feature extraction and multipath routing. In social feature extraction, we use entropy to extract the m most informative social features to create a feature space (F-space): (F1, F2,..., Fm), where Fi corresponds to a feature. The routing method then becomes a hypercube-based feature matching process, where the routing process is a step-by-step feature difference resolving process. We offer two special multipath routing schemes: node-disjoint-based routing and delegation-based routing. Extensive simulations on both real and synthetic traces are conducted in comparison with several existing approaches, including spray-and-wait routing, spray-and-focus routing, and social-aware routing based on betweenness centrality and similarity. In addition, the effectiveness of multipath routing is evaluated and compared to that of single-path routing.

A secure multi-hop routing for IoT communication

Abstract: This paper introduces a multi-hop routing protocol that enables secured IoT devices' communication. The routing protocol enables the IoT devices to authenticate before forming a new network or joining an existing network. The authentication uses multi-layer parameters to enhance the security of the communication. The proposed routing protocol embeds the multi-layer parameters into the routing algorithm, thus combining the authentication and routing processes without incurring significant overheads. The multi-layer parameters include a unique User-Controllable Identification, users' pre-agreed application(s), and a list of permitted devices, thus saving resources by maintaining smaller routing information. Experimental and field tests were conducted with results showing that our secure multi-hop routing is suitable to be deployed for IoT communication.

Survey on Mobile Ad Hoc Network Routing Protocols

Abstract: mobile ad-hoc network is characterized as network without any physical connections. In this network there is no fixed topology due to the mobility of nodes, interference, multipath propagation and path loss. Many Routing protocols have been developed to overcome these characteristics. The purpose of this paper is to review existing mobile ad-hoc proactive and reactive routing protocols depending on their proactive and reactive nature respectively. This review paper provides an overview of these protocols by presenting their characteristics, functionality, benefits and limitations and then makes their comparative analysis so to analyze their performance. The objective of this review paper is to provide analysis about improvement of these existing protocols.

High availability L3 gateways for logical networks

Abstract: Some embodiments provide a method for a network controller in a network control system that manages a plurality of logical networks. The method receives a specification of a logical network that includes a logical router. The method selects at least two host machines to implement a routing table for the logical router from several host machines designated for hosting logical routers. The selected host machines include a designated master host machine for the routing table. The method generates data tuples for provisioning a set of managed forwarding elements that implement the logical network to send data packets that require processing by the routing table to the selected host machines. The data tuples specify an order for the selected host machines with the designated master host machine as the first host machine in the specified order.

Multiprotocol intelligent household gateway apparatus and system thereof

Abstract: The invention supports access and integration of multiple heterogeneous networks including a wireless network, an on-site bus, an Ethernet and the like, and provides a household gateway protocol conversion and configuration method and device, and a device description file. A configurable protocol method is mainly employed to solve the problem of conversion among multiple heterogeneous protocols. A gateway is provided with configurable protocol software, the software generates description files of various device protocols, and a protocol conversion driving file is generated through a configuration method according to protocol attributes by use of a software tool. The gateway, after loading the driving file, converts the driving file to a communication protocol which can be identified by a device and automatically maps to generate a unified TCP/IP protocol frame routing table. The description files, based on a ClassAD task description language, are used for providing a flexible and extensible heterogeneous network model to describe any services or data. The gateway, through identification and description of device information, determines the type and meaning of the information, omits information parsing, reduces the time for processing the information by the gateway, and improves the real-time performance of a system.

LSGO: Link State aware Geographic Opportunistic routing protocol for VANETs

Abstract: Robust and efficient data delivery in vehicular ad hoc networks (VANETs) with high mobility is a challenging issue due to dynamic topology changes and unstable wireless links. The opportunistic routing protocols can improve the reliability of routing by making full use of the broadcast characteristics and assist in data transmission through additional backup links. In this paper, we propose a Link State aware Geographic Opportunistic routing protocol (LSGO) which exploits a combination of geographic location and the link state information as the routing metric. The LSGO aims to improve the reliability of data transmission in a highly dynamic environment, which selects the forwarders and prioritizes them based on the vehicle’s geographic location and the link’s quality. We compare the performance of LSGO with GpsrJ + which removes the unnecessary stop at a junction and greedy traffic aware routing protocol (GyTAR) using network simulator ns-2. The simulation results show that it opens more nodes to participate in the opportunistic data forwarding and increases a connection’s throughput while using no more network capacity than traditional routing. In the simulation, compared with other two protocols, when the number of vehicles and the average vehicle velocity increase, LSGO’s packet dropping rate is reduced and the network throughput is improved.

Packet classification for network routing

Abstract: Techniques for packet classification for network routing are disclosed. In some embodiments, packet classification for network routing includes receiving packets associated with a new flow at a security controller from a network device, in which the network device performs packet forwarding; classifying the flow; and determining an action for the flow based on a policy (e.g., a security policy). In some embodiments, the network device is a Software Defined Network (SDN) network device (e.g., a packet forwarding device that supports the OpenFlow protocol or another protocol).

Migration support for bit indexed explicit replication

Abstract: A method and network device are disclosed for multicast forwarding. In one embodiment, the method includes receiving at a node configured to use a bit-indexed forwarding table a multicast message comprising an incoming message bit array. The method further includes comparing the incoming message bit array to a first neighbor bit array within a first forwarding table entry, and determining that for at least one relative bit position in the bit arrays a corresponding destination node is both a destination for the message and a reachable destination from a first neighboring node. The method further includes forwarding toward the first neighboring node a copy of the message, where a first node on the path of the forwarded message is not configured to use a respective bit-indexed forwarding table. An embodiment of the device includes a network interface, a memory and a processor configured to perform steps of the method.

Neighbor Table Based Shortcut Tree Routing in ZigBee Wireless Networks

Abstract: The ZigBee tree routing is widely used in many resource-limited devices and applications, since it does not require any routing table and route discovery overhead to send a packet to the destination. However, the ZigBee tree routing has the fundamental limitation that a packet follows the tree topology; thus, it cannot provide the optimal routing path. In this paper, we propose the shortcut tree routing (STR) protocol that provides the near optimal routing path as well as maintains the advantages of the ZigBee tree routing such as no route discovery overhead and low memory consumption. The main idea of the shortcut tree routing is to calculate remaining hops from an arbitrary source to the destination using the hierarchical addressing scheme in ZigBee, and each source or intermediate node forwards a packet to the neighbor node with the smallest remaining hops in its neighbor table. The shortcut tree routing is fully distributed and compatible with ZigBee standard in that it only utilizes addressing scheme and neighbor table without any changes of the specification. The mathematical analysis proves that the 1-hop neighbor information improves overall network performances by providing an efficient routing path and distributing the traffic load concentrated on the tree links. In the performance evaluation, we show that the shortcut tree routing achieves the comparable performance to AODV with limited overhead of neighbor table maintenance as well as overwhelms the ZigBee tree routing in all the network conditions such as network density, network configurations, traffic type, and the network traffic.

Sweet Little Lies: Fake Topologies for Flexible Routing

Abstract: Link-state routing protocols (e.g., OSPF and IS-IS) are widely used because they are scalable, robust, and based on simple abstractions. Unfortunately, these protocols are also relatively inflexible, since they direct all traffic over shortest paths. In contrast, Software Defined Networking (SDN) offers fine-grained control over routing, at the expense of controller overhead, failover latency, and deployment challenges.We argue that future networks can achieve the benefits of both approaches through central control over the distributed route computation. The key idea, which we call Fibbing, is to have the controller trick the routers into seeing a fake topology that is carefully constructed to achieve the desired Forwarding Information Base (FIB). Given an acyclic forwarding graph for each destination, the controller computes an augmented topology with fake nodes (and destinations to announce there) and fake links (and link weights). The controller injects these "lies" into the link-state routing protocol, and the routers simply compute the paths accordingly. The controller can also select an augmented topology that triggers the use of specific backup paths when real links and routers fail. To reduce router load, our Fibbing algorithms compute augmented topologies of minimal size. Our preliminary evaluation on realistic ISP topologies shows that Fibbing works well in practice.