Distance Aware Routing for Hop Efficient Systems

Proactive routing protocols for mobile ad hoc networks (MANETs) follow on Optimum Routing Approach (ORA) to choose and use the optimal route at any time instant. On the other hand, on-demand routing protocols for MANETs have been traditionally designed using the Least Overhead Routing Approach (LORA) wherein a route determined using broadcast flooding-based route discovery is used as long as exists. With LROA, a route determined to be the best optimal route based on a particular route selection metric, may later become sub-optimal, and could be still used, if exists. In this paper, we evaluate the impact of the ORA and LORA strategies on minimum hop routing. Our hypothesis is that the LORA strategy could yield routes with a larger time-averaged hop count when compared to the minimum hop count of routes determined using the ORA strategy. We evaluate the two routing strategies under diverse conditions of network density, node mobility and mobility models such as the Random Waypoint model, City Section model and the Manhattan model. Simulation results illustrate that the hop count of routes maintained according to the LORA strategy is at most 12% greater than that incurred with the ORA strategy. The Random Waypoint model under the LORA strategy incurs the lowest hop count per path and the largest increase in hop count vis-à-vis the ORA strategy; on the other hand, the Manhattan model incurs a larger hop count per path and the smallest increase in hop count.KeywordsOptimum Routing Approach (ORA)Least Overhead Routing Approach (LORA)Mobility ModelHop CountMobile Ad hoc Networks

Ad Hoc Routing with Distributed Ordered Sequences

The authors implemented a 3-2 route scheme and overlap allowance in the automatic generation of custom cells layout targeted at GaAs and CMOS technology which requires three or more metal layers. The goal of this system is to create a dense layout with minimum area as the first concern and to have better performance than hand drawing and standard cell approaches. The system intends to solve the routing problems encountered by the conventional two-layer routing and nonoverlap methodology. The structured routing and placement scheme allows the users a choice in the algorithms used for the design process. The system has the capability to be expanded to perform the multiple-row cell layout and the automatic creation of a primitive library with different technologies.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

In this paper, we present a methodology employing statistical analysis and stochastic geometry to study geometric routing schemes in wireless ad hoc networks. In particular, we analyze the network-layer performance of one such scheme, the random [ 1/ 2]disk routing scheme, which is a localized geometric routing scheme in which each node chooses the next relay randomly among the nodes within its transmission range and in the general direction of the destination. The techniques developed in this paper enable us to establish the asymptotic connectivity and the convergence results for the mean and variance of the routing path lengths generated by geometric routing schemes in random wireless networks. In particular, we approximate the progress of the routing path toward the destination by a Markov process and determine the sufficient conditions that ensure the asymptotic connectivity for both dense and large-scale ad hoc networks deploying the random [ 1/ 2]disk routing scheme. Furthermore, using this Markov characterization, we show that the expected length (hop count) of the path generated by the random [ 1/ 2]disk routing scheme normalized by the length of the path generated by the ideal direct-line routing, converges to 3π/4 asymptotically. Moreover, we show that the variance-to-mean ratio of the routing path length converges to 9π <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /64-1 asymptotically. Through simulation, we show that the aforementioned asymptotic statistics are in fact quite accurate even for finite granularity and size of the network.

Manhattan Street Network (MSN) is a directed mesh network designed for a metropolitan area. To satisfy multiservice application, a routing scheme is required to support both datagram and virtual circuit services in MSN. The authors present a simple routing scheme that fulfils the need. The proposed scheme is based on computing hop counters (HCs), and then routing message(s) using their values. The hop counter computation is performed whenever a message is originated at a node to obtain a preferred path. Forward and backward learning are useful concepts in HC computation. The proposed routing scheme then discerns a virtual circuit or datagram service for a message in the network. To study the routing efficiency and traffic adaptivity, the authors have simulated this scheme, and the results compare favorably with that of an existing technique. >

Mobile Ad hoc Networks (MANET) comprises of self-organizing autonomous mobile nodes. MANETs are open and decentralized. Therefore they are vulnerable to malicious entities. MANETs are multi-hop wireless network where all nodes supportively maintain network connectivity without a centralized infrastructure. Since MANETs are infrastructure less and independent, the secure communication is the main issue. Therefore they are vulnerable to malicious entities. Here the location identity and traffic can be traced out by an outside observer. Anonymity means secure communications by hiding node identities and preventing traffic analysis attacks by outside observers. This paper proposes Position based Anonymous Routing Scheme in MANETs (PARS).Here the routing is based on Greedy Perimeter Stateless Routing Protocol. The objective is an anonymous routing protocol for the network. The proposed one is a zone based anonymous GPSR based protocol that can provide source, destination and route anonymity. Performance of the proposed system is compared with that of GPSR and AODV using Network Simulator. Index Terms: Anonymous routing, position-based routing, random forwarder, zone partition. I. Introduction Mobile Ad hoc Networks are collection of independent mobile nodes that can communicate by radio waves. It is an infrastructure less self-organizing network. The nodes that are in radio range can communicate by single hop or by multi hop with the help of intermediate nodes. The network is open and decentralized and fully distributed. So they are perfect choice for communication and information sharing. MANETs are susceptible to malicious entities that aim to alter and analyzed the traffic analysis by communication eaves dropping or attacking routing protocols. MANETs are characterized by their distributed operation, multi hop routing, dynamic topology and shared physical medium. Nodes in a MANET are independently free to move in any direction. Due to the lack of a centralized coordinator security is the major concern here. Wireless communication can endure interferences or malicious interceptions; whereas multi-hop communication assumes that each node will perform properly its functions to support network services. Further, self-organization increases the complexity of security management operations as access control, node authentication, secure routing and cryptographic key distribution. There is no fixed infrastructure and the topology is frequently changing due to node mobility or environmental changes. Therefore, it is very hard to maintain a stable and efficient end-to-end route in an ad-hoc network. Each node in MANET is energy constrained. There is verylimited physical security in MANET. The type of attacks can be Active attacks or Passive attacks. The common security issues are Passive attacks which include eaves dropping and information disclosure. Active attacks include Do Sand Data modification. There are other more specific problems with mobile ad hoc network such as vulnerability of channels and nodes, Byzantine black hole and Byzantine wormhole attack. The security issue also includes attacks that may inject erroneous routing information and diverting network traffic thus making routing inefficient. There are many methods to reduce the impact of these attacks, which include a secure routing using public and private key s to get a certification authority and use of digital signatures and prior it rust relationships. Routing is the process of communication from one node to the other host in a network. Routing is the process off or warding packet towards its destination using most efficient path. Routing efficiency is measured in terms of Number of hops, traffic, security, etc. Routing protocols in MANETs are divided as reactive proactive and hybrid. Reactive Protocol maintains the routes in on demand manner. In route discovery phase it floods the route request (RREQ) packets throughout the network. Dynamic source Routing (DSR), ad hoc on- demand distance vector routing (AODV) are some of the examples of reactive protocols. In proactive approach every node in the MANET continuously maintains the complete routing information of the entire network. This is accomplished by flooding network periodically with network status information. Global State Routing (GSR), Hierarchical State Routing (HSR) and Destination Sequenced Distance Vector Routing (DSDV) are some of the examples of proactive

Routing involves transferring data from one point to another within a network of interconnected devices. During the transmission of data, there is at least one middle nodethat is encountered in the network. Essentially, this concept includes two main tasks: findingthebest routing paths and sending packets across a network. The process of moving packets across an internetwork is known as packet switching, and while it is direct, determiningthepath can be quite complicated. Routing protocols utilize various metrics as a standardtodetermine the best path for routing packets to their destination, which may includethenumber of hops used by the routing algorithm to find the most efficient path to the packet'sdestination. Routing algorithms are responsible for discovering and managing routingtables, which store all the necessary route details for the packet in the path determination process. The details of the route differ depending on the specific routing algorithm. The routingtablescontain entries that include the IP address prefix and the corresponding next hop. Therearetwo main classifications of routing: static routing and dynamic routing. Static routingis whenthe routing scheme is set manually in the router, rather than dynamically. Static routinginvolves the creation of a routing table typically established by a network administrator. Dynamic routing is when an interior or exterior routing protocol is learning the routingstrategy. The routing is mainly determined by the network's condition, meaning the routingtable is influenced by how active the destination is.

Affinely-Adjustable Robust Counterparts are used to provide tractable alternatives to (two-stage) robust programs with arbitrary recourse. We apply them to robust network design with polyhedral demand uncertainty, introducing the affine routing principle. We compare the affine routing to the well-studied static and dynamic routing schemes for robust network design. It is shown that affine routing can be seen as a generalization of the widely used static routing still being tractable and providing cheaper solutions. We investigate properties on the demand polytope under which affine routings reduce to static routings and also develop conditions on the uncertainty set leading to dynamic routings being affine. We show however that affine routings suffer from the drawback that (even strongly) dominated demand vectors are not necessarily supported by affine solutions.

Opportunistic network is the current area of research which facilitates message delivery between the nodes where there is no end-to-end connectivity. The most of the existing routing schemes in Opportunistic networks consume high resources and leads to decline in network efficiency. So, designing an efficient routing scheme for OppNets always remains a stimulating task due to high mobility of nodes, absence of an end-to-end connectivity and the lack of further knowledge about the network topology. In this research paper we propose a novel Fuzzy based Social relationshipAware Routing (F-SAR) scheme in which the decision of the best forwarder to forward the message depend on fuzzy inference system considering residual energy, buffer availability and social relationship of nodes. This routing scheme is simulated in “The ONE” simulator and the results shows that it outperforms SnW, Prophet, and FLDEAR in terms of delivery rate, message transmission overhead, and average latency

Today, the architecture of computer networks using IP addressing is focused on interaction between network devices with «binding» of data objects to specific sources, which leads to a decrease in bandwidth and network congestion. In information-centric networks (ICN), routing and caching of data objects on intermediate network nodes during transmission from source to recipient is performed using unique names. The purpose of the study is to analyze the performance of various caching strategies in terms of cache hit rate and request response time for data objects. Materials and methods. The following caching strategies were selected for the study: Leave Copy Everywhere, Leave Copy Down, Probabilistic Cache, random caching, Bernoulli probabilistic caching, symmetric hash routing scheme, asymmetric hash routing scheme, multicast scheme. The following metrics were calculated: cache hit rate, time delay in delivering the requested data object to the recipient, channel load when transmitting the data object, and the length of the data object’s path. The metrics were measured taking into account the following characteristics: asymmetry in the distribution of data object popularity, the total size of network caches of intermediate nodes as a share of the total number of data objects. The simulation was performed for three network topologies: GARR (Italian academic network), GEANT (European academic network), WIDE (Japanese academic network) using the Icarus 8.0 simulator. Results. The use of symmetric hash routing and multicast schemes allowed us to obtain the highest cache hit rate. The lowest cache hit rate in most tests is observed when using the asymmetric hash routing scheme, since the path of a data object to the recipient may not pass through the router responsible for caching. When using symmetric hash routing and multicast schemes, it was possible to obtain a lower delivery delay compared to other strategies. When using the Leave Copy Down caching strategy, the delivery delay with an increase in the data object popularity asymmetry indicator takes smaller values ​​than that of the hash routing schemes. The highest delay among the strategies under consideration is observed when using the asymmetric hash routing scheme. The use of the hash routing scheme leads to a relatively high value of the communication channel load parameter. The channel load indicator values ​​for such strategies as Leave Copy Everywhere (LCE), Leave Copy Down (LCD), Probabilistic Cache (ProbCache), random choice caching (RAND_CHOICE), Bernoulli caching (RAND_BERNOULLI) do not differ much from each other. The use of hash routing schemes leads to an increase in the length of the data delivery path, especially when using symmetric hash routing schemes and multicasting, since the path of the data object to the recipient may pass through the router responsible for caching, which is not always the shortest. Conclusions. Hash routing schemes with caching in some cases are a completely reasonable alternative to methods that are focused on caching along the request path and do not involve the use of hash functions to match the unique name of the data object and the router intended for caching. The practical significance of this work lies in the possibility of using the results of the study when choosing a particular caching strategy on intermediate network devices depending on the characteristics of the communication channel, in particular, the network topology and the degree of popularity of the transmitted data object.

In this paper, we propose a multi-objective traffic engineering scheme using different distribution trees to dynamic multicast groups (in which egress nodes can change during the connection's lifetime). If a multicast tree is recomputed from scratch, it may consume a considerable amount of CPU time and all communication using the multicast tree will be temporarily interrupted. To alleviate these drawbacks we propose a dynamic optimization model that makes use of a previously computed multicast tree (static model) in order to add new egress nodes. Using these two models, our aim is to combine into a single aggregated metric, the following weighting objectives: maximum link utilization, hop count, total bandwidth consumption and total end-to-end delay. Moreover, our proposal solves the traffic split ratio for multiple trees. We compare the dynamic and static multicast routing models using SNOPT solver. The proposed approach can be applied in MPLS networks by allowing explicit routes to be established in multicast events.

The paper describes new method for routing classification of the packets in the networks with static routing. Static routing is mostly used in the stable and well-controlled networks, which are sensitive to the additional complexity introduced by the dynamic routing schemes. For example, it is a straightforward choice for the embedded networks on terminal. The available solutions for the static routing require full-size or longest prefix-based aggregated routing table, which is inefficient taking into account static nature of the performed routing decisions. The standard approach is based on the full implementation of the route lookup procedure, which for every packet performs search for the longest prefix match in the routing table. As a result, it increases implementation complexity of the network end points and switches, requires high speed memory for storing routing tables, and leads to an additional processing delay and energy consumption for each transmitted packet. This work is based on the observation that clever planning of the networks with static routing allows applying new principles of route lookup. As a consequence it allows significantly reduce complexity of the packet classification and forwarding procedures and minimize amount of consumed resources. Complexity reduction of the packets classification and forwarding procedures allows simplifying implementation of the networking part of the protocol stack, which results in reduction of the device components cost, decrease of the power and memory consumption, as well as the packet processing delay. The paper contains a description of the proposed route classification method and discusses its applicability for broad range of networks with static routing.

Background: The Internet of Things (IoT) is an embryonic model that converts realworld things (objects) into smarter devices. IoT is applicable to a variety of application domains, including healthcare, smart grid, and agriculture. Low Power Wide Area Network (LPWAN) technology can transmit data over long distances with a low data rate without using the internet. Therefore, this technology is suitable for sending sensor measurement data in Internet of Things (IoT) applications. LPWANs, such as LoRa, use a star topology to reach their coverage to the maximum power that can be transmitted, considering the environmental conditions in the test area and the LoRa parameters used. Whereas for application development in rural areas, there is no internet connection, and often longer coverage is required from the sensor node to the gateway. Objective: This study aims to increase the transmission range from the end node to the gateway by adding an intermediate node. It is used as a relay from the end node to the gateway. Method: Static routing was applied so that any broadcast data from the end node would be forwarded first to the intermediate node and then to the gateway. Results: The LoRa transmission range expanded by changing the topology from peer-to-peer to multi-hop. An intermediate node between the transmitter (end node) and the gateway is available. In the experiment performed, a multi-hop with static routes successfully expanded the distance from 150 meters (single hop) to 250 meters (multi-hop), with a packet delivery ratio of 97%. In this experiment, GPS Ublox Neo was used for the sensor position and was successfully tested on the end node with an accuracy rate of 2.4% for latitude and 0.2% for longitude. Conclusion: The transmission range from the sensor node to the gateway can be extended using static routing by installing an intermediate node between the gateway and the sensor node. The data from the end node is successfully received by the gateway.

Routing in ad hoc networks is a challenging task. During the route discovery phase of AODV-like routing schemes, flooding of route request (RREQ) packets creates broadcast storm, which increases the possibility of packet collision. On the other hand, location-aided routing schemes may mitigate the problem by limiting the broadcast region. However, such schemes might fail in many cases where conventional routing schemes, such as AODV, can easily find a route. Besides, it is costly for every node to maintain location information of all nodes in the network. To overcome the above mentioned problems, we propose a routing scheme named Farthest Node Only (FARNO), where only the farthest node in each quadrant is designated to forward an RREQ packet. Simulation results reveal that the proposed scheme can prevent the above mentioned problems and perform well in many aspects.

When a router fails in IP-over-EON, some traffics are affected. Each affected traffic attempts to be restored through the best alternate path among alternate paths offered. Some conventional routing schemes are commonly used to solve problems in IP over optical networks, namely k-shortest paths (KSP), hop count (HC), and link-disjoint (LD). The three schemes are fixed-alternate routing (FAR) schemes. However, the alternate paths it generates cannot adjust to the current network conditions due to a router outage. Therefore, this study proposes an adaptive routing, i.e., adaptive lightpath reconfiguration paths (ALRP) routing. ALRP routing explores the number of paths between the source and destination pairs for each affected traffic and then selects the best alternate paths by maximizing the utilization of unaffected lightpaths. The goal is to minimize costs relate to the number of lightpath reconfiguration and additional power consumption due to the recovery of affected traffic. Based on simulations conducted using two network topologies, namely seven-node topology and NSFNET topology, it was found that the proposed ALRP routing produced better results compared to the three conventional routing schemes in minimizing the addition of both costs.