Showing papers on "Routing table published in 2016"

E-CARP: An Energy Efficient Routing Protocol for UWSNs in the Internet of Underwater Things

Abstract: With the advance of the Internet of Underwater Things, smart things are deployed under the water and form the underwater wireless sensor networks (UWSNs), to facilitate the discovery of vast unexplored ocean volume. A routing protocol, which is not expensive in packets forwarding and energy consumption, is fundamental for sensory data gathering and transmitting in UWSNs. To address this challenge, this paper proposes Enhanced CARP (E-CARP), which is an enhanced version of the channel-aware routing protocol (CARP) developed by S. Basagni et al. , to achieve the location-free and greedy hop-by-hop packet forwarding strategy. In general, CARP does not consider the reusability of previously collected sensory data to support certain domain applications afterward, which induces data packets forwarding which may not be beneficial to applications. Besides, the PING - PONG strategy in CARP can be simplified for selecting the most appropriate relay node at each time point, when the network topology is relatively steady. These two research problems have been addressed by our E-CARP. Simulation results validate that our technique can decrease the communication cost significantly and increase the network capability to a certain extent.

Joint Clustering and Routing Design for Reliable and Efficient Data Collection in Large-Scale Wireless Sensor Networks

Abstract: For data collection in large-scale wireless sensor networks (WSNs), dynamic clustering provides a scalable and energy-efficient solution, which uses cluster head (CH) rotation and cluster range assignment algorithms to balance the energy consumption. Nevertheless, most existing works consider the clustering and routing as two isolated issues, which is harmful to the connectivity and energy efficiency of the network. In this paper, we provide a detailed analysis on the relations between clustering and routing, and then propose a joint clustering and routing (JCR) protocol for reliable and efficient data collection in large-scale WSN. JCR adopts the backoff timer and gradient routing to generate connected and efficient intercluster topology with the constraint of maximum transmission range. The relations between clustering and routing in JCR are further exploited by theoretical and numerical analyses. The results show that the multihop routing in JCR may lead to the unbalanced CH selection. Then, the solution is provided to optimize the network lifetime by considering the gradient of one-hop neighbor nodes in the setting of backoff timer. Theoretical analysis and simulation results prove the connectivity and efficiency of the network topology generated by JCR.

Wdfad-dbr

Abstract: The design of routing protocols for Underwater Acoustic Sensor Networks (UASNs) poses many challenges due to long propagation, high mobility, limited bandwidth, multi-path and Doppler effect. Because of the void-hole caused by the uneven distribution of nodes and sparse deployment, the selection of next hop forwarding nodes only based on the state of current node may result in the failure of forwarding in the local sparse region. In order to reduce the probability of encountering void holes in the sparse networks, in this paper we present weighting depth and forwarding area division DBR routing protocol, called WDFAD-DBR. The novelties of WDFAD-DBR lie in: firstly, next forwarding nodes are selected according to the weighting sum of depth difference of two hops, which considers not only the current depth but also the depth of expected next hop. In this way, the probability of meeting void holes is effectively reduced. Secondly, the mechanisms for forwarding area division and neighbor node prediction are designed to reduce the energy consumption caused by duplicated packets and neighbors' requests, respectively. Thirdly, we make theoretical analyses on routing performance in case of considering channel contending with respect to delivery ratio, energy consumption and average end-to-end delay. Finally we conduct extensive simulations using NS-3 simulator to verify the effectiveness and validity of WDFAD-DBR.

On the Construction of Data Aggregation Tree With Maximizing Lifetime in Large-Scale Wireless Sensor Networks

Abstract: Data aggregation protocols are generally utilized to extend the lifetime of sensor networks by reducing the communication cost. Traditionally, tree-based structured approaches that are a basic operation for the sink to periodically collect reports from all sensors were concerned about many applications. Since the data aggregation process usually proceeds for many rounds, it is important to collect these data efficiently, that is, to reduce the energy cost of data transmission. Under such applications, a tree is usually adopted as the routing structure to save the computation costs when maintaining the routing tables of sensors. In our previous work, we have demonstrated that multiple trees, as well as split trees, can provide additional lifetime extensions when certain nodes are deployed in a wireless sensor network. In this paper, we explore how the number of the family-set of trees influences the lifetime gain, and we work on the problem of constructing data aggregation trees that minimizes the total energy cost of data transmission under diverse set of scenarios and network query region. Through dividing query area, the sensory and aggregation data have been returned through a number of different forwarding trees within each sub query area, which reduces the network hot spots. To evaluate the performance of the proposed approach, we have compared and analyzed an angular division routing algorithm and query region division routing with LEACH. Theoretical and experimental results illustrate that the query region division algorithm based on angle leads to lower energy cost in comparison with the models reported in the literature.

A Secure Routing Protocol Based on RPL for Internet of Things

Abstract: Data transportation and routing in Internet of Things (IoT) is a challenging issue where massive data collection and gathering are predictable. The Routing Protocol for Low- power and Lossy Networks (RPL) is one of the best candidates to ensure routing in 6LoWPAN networks. However, RPL is vulnerable to a number of attacks related to exchanged control messages. In this paper, we propose a new secure routing protocol based on RPL referred to as Secure-RPL (SRPL). The main aim of SRPL is to prevent misbehaving nodes from maliciously changing control message values such as the rank of a node that may disturb a network by creating a fake topology. We introduce the concept of rank threshold along with hash chain authentication technique to deal with internal attacks like sinkhole, black hole, selective forwarding attacks etc. Simulation results show that SRPL is robust and resistant to this kind of attacks based on malicious manipulation of RPL metrics.

A performance comparison of delay-tolerant network routing protocols

Abstract: Networks that lack continuous end-to-end connections among their nodes due to node mobility, constrained power sources, or limited data storage space are called DTNs. To overcome the intermittent connectivity, DTN nodes store and carry the data packets they receive until they come into communication range of each other. In addition, they spread multiple copies of the same packet on the network to increase the delivery probability. In recent years, several routing protocols have been developed specifically for DTNs. These protocols vary in the number of copies they spread and the information they use to guide the packets to their destinations. There have been some reviews of those protocols, but no performance comparison has been conducted. In this article, we study four well-known DTN routing protocols: EPIDEMIC, Spray-and-Wait, PROPHET, and MAXPROP. We introduce a procedural form to present the protocols. We measure the performance of the protocols in terms of packet delivery, delivery cost, and average packet delay. We compare the protocols' performance together with the results of optimal routing using real-life scenarios of vehicles and pedestrians roaming in a city. We conduct several simulation experiments to show the impact of changing buffer capacity, packet lifetime, packet generation rate, and number of nodes on the performance metrics. The article is concluded by providing guidelines to develop an efficient DTN routing protocol. To the best of our knowledge, this work is the first to provide a detailed performance comparison among the diverse collection of DTN routing protocols.

Defence against Black Hole and Selective Forwarding Attacks for Medical WSNs in the IoT.

Abstract: Wireless sensor networks (WSNs) are being used to facilitate monitoring of patients in hospital and home environments. These systems consist of a variety of different components/sensors and many processes like clustering, routing, security, and self-organization. Routing is necessary for medical-based WSNs because it allows remote data delivery and it facilitates network scalability in large hospitals. However, routing entails several problems, mainly due to the open nature of wireless networks, and these need to be addressed. This paper looks at two of the problems that arise due to wireless routing between the nodes and access points of a medical WSN (for IoT use): black hole and selective forwarding (SF) attacks. A solution to the former can readily be provided through the use of cryptographic hashes, while the latter makes use of a neighbourhood watch and threshold-based analysis to detect and correct SF attacks. The scheme proposed here is capable of detecting a selective forwarding attack with over 96% accuracy and successfully identifying the malicious node with 83% accuracy.

An experimental investigation of hyperbolic routing with a smart forwarding plane in NDN

Abstract: Routing in NDN networks must scale in terms of forwarding table size and routing protocol overhead. Hyperbolic routing (HR) presents a potential solution to address the routing scalability problem, because it does not use traditional forwarding tables or exchange routing updates upon changes in network topologies. Although HR has the drawbacks of producing sub-optimal routes or local minima for some destinations, these issues can be mitigated by NDN's intelligent data forwarding plane. However, HR's viability still depends on both the quality of the routes HR provides and the overhead incurred at the forwarding plane due to HR's sub-optimal behavior. We designed a new forwarding strategy called Adaptive Smoothed RTT-based Forwarding (ASF) to mitigate HR's sub-optimal path selection. This paper describes our experimental investigation into the packet delivery delay and overhead under HR as compared with Named-Data Link State Routing (NLSR), which calculates shortest paths. We run emulation experiments using various topologies with different failure scenarios, probing intervals, and maximum number of next hops for a name prefix. Our results show that HR's delay stretch has a median close to 1 and a 95th-percentile around or below 2, which does not grow with the network size. HR's message overhead in dynamic topologies is nearly independent of the network size, while NLSR's overhead grows polynomially at least. These results suggest that HR offers a more scalable routing solution with little impact on the optimality of routing paths.

On the Construction of Data Aggregation Tree with Minimum Energy Cost in Wireless Sensor Networks: NP-Completeness and Approximation Algorithms

Abstract: In many applications, it is a basic operation for the sink to periodically collect reports from all sensors. Since the data gathering process usually proceeds for many rounds, it is important to collect these data efficiently, that is, to reduce the energy cost of data transmission. Under such applications, a tree is usually adopted as the routing structure to save the computation costs for maintaining the routing tables of sensors. In this paper, we work on the problem of constructing a data aggregation tree that minimizes the total energy cost of data transmission in a wireless sensor network. In addition, we also address such a problem in the wireless sensor network where relay nodes exist and consider the cases where the link quality is not perfect. We show that these problems are NP-complete and propose $O(1)$ -approximation algorithms for each of them. Simulations show that the proposed algorithms have good performance in terms of energy cost.

Scalable Multi-Failure Fast Failover via Forwarding Table Compression

Abstract: In datacenter networks, link and switch failures are a common occurrence. Although most of these failures do not disconnect the underlying topology, they do cause routing failures, disrupting communications between some hosts. Unfortunately, current 1:1 redundancy groups are only partly effective at reducing the impact of these routing failures. In principle, local fast failover schemes, such as OpenFlow fast failover groups, could reduce the impact by preinstalling backup routes that protect against multiple simultaneous failures. However, providing a sufficient number of backup routes within the available space provided by the forwarding tables of datacenter switches is challenging. To solve this problem, we contribute a new forwarding table compression algorithm. Further, we introduce the concept of compression-aware routing to improve the achieved compression ratio. Lastly, we have created Plinko, a new forwarding model that is designed to have more easily compressible forwarding tables. All optimizations combined, we often saw compression ratios ranging from 2.10x to 19.29x.

Mobile Ad-Hoc Networks Applications and Its Challenges

Abstract: Mobile Ad-Hoc Network (MANET) is an infrastructure less wireless network of autonomous collection of mobile nodes (Smart phones, Laptops, iPads, PDAs etc.). Network is self-configured to reconstruct its topology and routing table information for the exchange of data packets on the joining and leaving of each node on ad-hoc basis. This paper is based on the MANET applications and challenges. The researchers can get the overall concept of MANET as well as its applications and challenges.

A Street-Centric Routing Protocol Based on Microtopology in Vehicular Ad Hoc Networks

Abstract: In a vehicular ad hoc network (VANET), high mobility and uneven distribution of vehicles are important factors affecting the performance of routing protocols. The high mobility may cause frequent changes of network topology, whereas the uneven distribution of vehicles may lead to routing failures due to network partition; even high density of vehicles may cause severe wireless channel contentions in an urban environment. In this paper, we propose a novel concept called the microtopology (MT), which consists of vehicles and wireless links among vehicles along a street as a basic component of routing paths and even the entire network topology. We abstract the MT model reflecting the dynamic routing-related characteristics in practical urban scenarios along streets, including the effect of mobility of vehicles, signal fading, wireless channel contention, and existing data traffic. We first analyze the endside-to-endside routing performance in an MT as a basis of routing decision. Then, we propose a novel street-centric routing protocol based on MT (SRPMT) along the streets for VANETs. Simulation results show that our proposed SRPMT protocol achieves higher data delivery rate and shorter average end-to-end delay compared with the performance of greedy perimeter stateless routing (GPSR) and greedy traffic-aware routing (GyTAR).

SDN Partitioning: A Centralized Control Plane for Distributed Routing Protocols

Abstract: Hybrid IP networks that use both control paradigms - distributed and centralized - promise the best of two worlds: programmability and agility of SDN, and reliability and fault tolerance of distributed routing protocols like OSPF. The common approaches follow a division of labor concept, where SDN controls prioritized traffic and OSPF assures care-free operation of best effort traffic. We propose SDN Partitioning, which establishes centralized control over the distributed routing protocol by partitioning the topology into sub-domains with SDN-enabled border nodes, such that OSPF's routing updates have to traverse SDN border nodes to reach neighboring sub-domains. This allows the central controller to modify how sub-domains view one another, which in turn allows to steer inter-sub-domain traffic. The degree of dynamic control against simplicity of OSPF can be trade off by adjusting the size of the sub-domains. This paper explains the technical requirements, presents a novel scheme for balanced topology partitioning, and provides the models for common network management tasks. Our performance evaluation shows that - already in its minimum configuration with two sub-domains - SDN Partitioning provides significant improvements in all respects compared to legacy routing protocols, whereas smaller sub-domains provide network control capabilities comparable to full SDN deployment.

Optimizing restoration with segment routing

Abstract: Segment routing is a new proposed routing mechanism for simplified and flexible path control in IP/MPLS networks. It builds on existing network routing and connection management protocols and one of its important features is the automatic rerouting of connections upon failure. Re-routing can be done with available restoration mechanisms including IGP-based rerouting and fast reroute with loop-free alternates. This is particularly attractive for use in Software Defined Networks (SDN) because the central controller need only be involved at connection set-up time and failures are handled automatically in a distributed manner. A significant challenge in restoration optimization in segment routed networks is the centralized determination of connections primary paths so as to enable the best sharing of restoration bandwidth over non-simultaneous network failures. We formulate this problem as a linear programming problem and develop an efficient primal-dual algorithm for the solution. We also develop a simple randomized rounding scheme for cases when there are additional constraints on segment routing. We demonstrate the significant capacity benefits achievable from this optimized restoration with segment routing.

Routing loop detecting method and system based on SDN

Abstract: The invention discloses a routing loop detecting method based on a SDN. The routing loop detecting method comprises the following steps of: obtaining routing table information and routing event information of each node in a network in real time; constructing a real-time topological structure of the network according to the obtained routing table information and routing event information; constructing a multi-routing-form prefix tree matched with the longest prefix by adopting a hierarchical compression method according to the real-time topological structure, and storing a forwarding subnet segment in the routing table of each node; generating a routing next-hop table for each subnet node in the prefix tree in the subnet segment, in which the loop is necessary to judge, and traversing each subnet node of the prefix tree to generate a node forwarding figure; and judging whether the routing loop exists or not according to the node forwarding figure. The invention further discloses a routing loop detecting system based on the SDN. By means of the routing loop detecting method and system based on the SDN, the routing loop detection efficiency and accuracy are increased; and simultaneously, the storage space and the calculation time are reduced.

Dynamic routing for network throughput maximization in software-defined networks

Abstract: Software-Defined Networking (SDN) has emerged as the paradigm of the next-generation networking through separating the data control plane from the data plane. The forwarding routing table at each of its switch nodes is usually implemented by expensive and power-hungry Ternary Content Addressable Memory (TCAM) that only has limited number of entries, and the bandwidth at each of its links is bounded too. Under this new network architecture, providing a quality service to users by admitting user requests to meet their resource demands is challenging, and very little attention has ever been paid in this regard. In this paper, we will study online unicast and multicast request admissions in SDNs with the aim to maximize the network throughput under both critical network resources and user bandwidth demand constraints, for which we first propose a novel model to characterize the usage costs of node and link resources. We then devise efficient online algorithms for unicast and multicast requests. We also analyze the competitive ratios of the proposed online algorithms, which are Ο (log n) and O(K∊ log n) for unicasting and multicasting, respectively, where n is the network size, K is the maximum number of members in a multicast request, and ∊ is a constant with 0 < e ≤ 1. We finally evaluate the proposed algorithms empirically through simulations. The simulation results demonstrate that the proposed algorithms are very promising.

SCMon: Leveraging segment routing to improve network monitoring

Abstract: To guarantee correct operation of their networks, operators have to promptly detect and diagnose data-plane issues, like broken interface cards or link failures. Networks are becoming more complex, with a growing number of Equal Cost MultiPath (ECMP) and link bundles. Hence, some data-plane problems (e.g. silent packet dropping at one router) can hardly be detected with control-plane protocols or simple monitoring tools like ping or traceroute. In this paper, we propose a new technique, called SCMon, that enables continuous monitoring of the data-plane, in order to track the health of all routers and links. SCMon leverages the recently proposed Segment Routing (SR) architecture to monitor the entire network with a single box (and no additional monitoring protocol). In particular, SCMon uses SR to (i) force monitoring probes to travel over cycles; and (ii) test parallel links and bundles at a per-link granularity. We present original algorithms to compute cycles that cover all network links with a limited number of SR segments. Further, we prototype and evaluate SCMon both with simulations and Linux-based emulations. Our experiments show that SCMon quickly detects and precisely pinpoints data-plane problems, with a limited overhead.

Logical router with multiple routing components

Abstract: Some embodiments provide a method for implementing a logical router in a network. The method receives a definition of a logical router for implementation on a set of network elements. The method defines several routing components for the logical router. Each of the defined routing components includes a separate set of routes and separate set of logical interfaces. The method implements the several routing components in the network. In some embodiments, the several routing components include one distributed routing component and several centralized routing components.

PIS: A Multi-Dimensional Routing Protocol for Socially-Aware Networking

Abstract: Socially-aware networking is an emerging paradigm for intermittently connected networks consisting of mobile users with social relationships and characteristics. In this setting, humans are the main carriers of mobile devices. Hence, their connections, social features, and behaviors can be exploited to improve the performance of data forwarding protocols. In this paper, we first explore the impact of three social features, namely physical proximity, user interests, and social relationship on users’ daily routines. Then, we propose a multi-dimensional routing protocol called Proximity-Interest-Social (PIS) protocol in which the three different social dimensions are integrated into a unified distance function in order to select optimal intermediate data carriers. PIS protocol utilizes a time slot management mechanism to discover users’ movement similarities in different time periods during a day. We compare the performance of PIS to Epidemic, PROPHET, and SimBet routing protocols using SIGCOMM09 and INFOCOM06 data sets. The experiment results show that PIS outperforms other benchmark routing protocols with the highest data delivery ratio with a low communication overhead.

New Approach for Efficient IP Address Lookup Using a Bloom Filter in Trie-Based Algorithms

Abstract: IP address lookup operation determines the longest prefix matching each incoming destination address. As a fundamental operation for packet forwarding at Internet routers, search speed for routing table lookup is the most important performance metric. Previous researches have shown that the search performance of trie-based algorithms can be improved by adding on-chip Bloom filters. In these algorithms, an on-chip Bloom filter identifies the membership of a node in an off-chip trie, and the number of trie accesses is reduced, because the Bloom filter can filter out accesses to non-existing nodes in the trie. In this paper, we propose a new method of utilizing a Bloom filter for the IP address lookup problem. In the previous Bloom filter-based approach, false positiveness has to be identified by accessing the off-chip trie for every positive result, since false positives can produce wrong results. In our proposed approach, the false positiveness of a Bloom filter is not necessarily identified by making false positives not mislead the search. Hence the number of off-chip trie accesses are significantly reduced. Simulation results show that the best matching prefix can be found with a single off-chip access in average and in the worst-case with the reasonable size of a Bloom filter in our proposed method.

Experimental Demonstration of Segment Routing

Abstract: Segment routing (SR) technology has been recently proposed to enforce effective routing strategies without relying on signaling protocols. So far, the SR technology has received limited attention within the scientific community. In this paper, two SR implementations are presented and successfully demonstrated in two different network testbeds. The first implementation focuses on a software defined networking (SDN) scenario where nodes consist of OpenFlow switches and the SR controller is a specifically designed enhanced version of an OpenFlow controller. The second implementation includes a novel path computation element (PCE) scenario where nodes consist of commercially available IP/MPLS routers and the SR controller is a new extended version of a PCE solution. Both implementations have been successfully applied to demonstrate dynamic traffic rerouting. In particular, by enforcing different segment list configurations at the ingress node, rerouting is effectively achieved with no packet loss and without requiring the use of signaling protocols. Effective scalability performance is achieved in both proposed implementations, under different segment list conditions.

A Resilient Routing Algorithm with Formal Reliability Analysis for Partially Connected 3D-NoCs

Abstract: 3D ICs can take advantage of a scalable communication platform, commonly referred to as the Networks-on-Chip (NoC). In the basic form of 3D-NoC, all routers are vertically connected. Partially connected 3D-NoC has emerged because of physical limitations of using vertical links. Routing is of great importance in such partially connected architectures. A high-performance, fault-tolerant and adaptive routing strategy with respect to the communication flow among the cores is crucial while freedom from livelock and deadlock has to be guaranteed. In this paper we introduce a new routing algorithm for partially connected 3D-NoCs. The routing algorithm is adaptive and tolerates the faults on vertical links as compared to the predesigned routing algorithms. Our results show a $40-50\%$ improvement in the fraction of intact inter-level communications when the fault tolerant algorithm is used. This routing algorithm is light-weight and has only one virtual channel along the $Y$ dimension.

Secure Data Collection in Wireless Sensor Networks using Randomized Dispersive Routes

Abstract: The Compromised-node and denial-of- service are two key attacks in wireless sensor networks (WSNs).We study routing mechanisms that circumvent (bypass) black holes formed by these attacks. We argue that existing multi-path routing approaches are vulnerable to such attacks, mainly due to their deterministic nature. So once an adversary acquires the routing algorithm, it can compute the same routes known to the source, and hence endanger all information sent over these routes. In this paper, we

Fault-Tolerant Networks-on-Chip Routing With Coarse and Fine-Grained Look-Ahead

Abstract: Fault tolerance and adaptive capabilities are challenges for modern networks-on-chip (NoC) due to the increase in physical defects in advanced manufacturing processes. Two novel adaptive routing algorithms, namely coarse and fine-grained (FG) look-ahead algorithms, are proposed in this paper to enhance 2-D mesh/torus NoC system fault-tolerant capabilities. These strategies use fault flag codes from neighboring nodes to obtain the status or conditions of real-time traffic in an NoC region, then calculate the path weights and choose the route to forward packets. This approach enables the router to minimize congestion for the adjacent connected channels and also to bypass a path with faulty channels by looking ahead at distant neighboring router paths. The novelty of the proposed routing algorithms is the weighted path selection strategies, which make near-optimal routing decisions to maintain the NoC system performance under high fault rates. Results show that the proposed routing algorithms can achieve performance improvement compared to other state of the art works under various traffic loads and high fault rates. The routing algorithm with FG look-ahead capability achieves a higher throughput compared with the coarse-grained approach under complex fault patterns. The hardware area/power overheads of both routing approaches are relatively low which does not prohibit scalability for large-scale NoC implementations.

A grid-based reliable routing protocol for wireless sensor networks with randomly distributed clusters

Abstract: The need for implementing reliable data transfer in wireless sensor networks is still an open issue in the research community. Although cluster routing schemes are characterized by their low overhead and efficiency in reliable data transfer in traditional wireless sensor network, this potential is still yet to be utilized for viable routing options in the environment with obstacles and voids, via greedy and perimeter forwarding. In this paper, a novel Grid-Based Reliable Routing (GBRR) technique is presented. This is achieved by the creation of virtual clusters based on square grids from which the next hop choice is made based on intra-cluster and inter-cluster communication quality. The simulation result shows that the developed scheme can make more advancement to the BS as against the usual decisions of relevant clustering route select operations, while ensuring channel quality. Further simulation results have shown the enhanced reliability, lower latency and energy efficiency of the presented scheme with randomly nodes and obstacles distribution.

Route server mode for dynamic routing between logical and physical networks

Abstract: Some embodiments provide a method for configuring a logical router that interfaces with an external network. The method receives a configuration for a logical network that includes a logical router with several interfaces that connect to at least one physical router external to the logical network. The method selects a separate host machine to host a centralized routing component for each of the interfaces. The method selects a particular one of the host machines for operating a dynamic routing protocol control plane that receives routing protocol data from each of the centralized routing components and updates routing tables of each of the centralized routing components.