Random Path Selection Research Articles

Spatial Path Selection and Network Topology Optimisation in P2P Anonymous Routing Protocols

To anonymous internet traffic, many popular protocols route traffic through a network of nodes in order to conceal information about the request. However, routing traffic through other nodes inherently introduces added latency. Over the past two decades, there were many attempts to improve the path selection in order to decrease latency with little or no trade-off in terms of security, and anonymity. In this paper, we show the potential use of geo-sharding in decentralized routing networks to improve fault-tolerance, and latency. Such networks can be used as a communication layer for Edge devices computing huge amounts of data. Specifically, we focus our work on Low Latency Anonymous Routing Protocol (LLARP), a protocol built on top of Oxen blockchain that aims to achieve internet privacy. We analyse the existing network of Service Nodes(SN), observe cloud provider centralisation, and propose a high level protocol that provides incentives for a better geographical distribution mitigating potential cloud provider/country wide service dropouts. Additionally, the protocol level information about geographical location can be used to improve client’s path (the string of nodes that will participate in the transaction) selection, decreasing network latency. We show the feasibility of our approach by comparing it with the random path selection in a simulated environment. We observe marginal drops in average latency when selecting paths geographically closer to each other.

Construction of urban landscape ecological security pattern based on circuit theory: A case study of Hengyang City, Hunan Province, China.

The identification of ecological sources and corridors plays an important role in the construction of ecological security pattern. However, previous studies mainly concentrated on the optimal path selection of species migration and diffusion rather than the random path selection of the species, which makes most conclusions fail to objectively reveal the process of species migration and diffusion. Taking the downtown area of Hengyang City as an example, we selected the ecological sources and ecological corridors with the habitat quality analysis module of InVEST and Circuitscape 4.0 and evaluated the importance and connectivity of relevant ecological elements with the Linkage Mapper, with the aim to construct the ecological security pattern and delimitate the regions prior to ecological restoration. The results showed that there were 85 ecological sources dominated by woodland and grassland, together with a small number of ponds and beaches, which mainly distributed in the southwest of Zhengxiang District, the west of Yanfeng District, the northeast and south central of Zhuhui District, with a total area of 11.8 km2. There were 60 ecological sources with centrality greater than 100, accounting for 70.6% of the total. There were 217 ecological corridors and five potential ecological corridors mainly composed of forest land, among which the proportion of shrubbery and sparse forest land was higher. The corridors with higher importance were mainly distributed in the west of the studied area. After removing the barriers, the regional connectivity had been significantly improved, with the highest extent of 54.9%. The priority areas of ecological restoration were classified into three levels according to the value of cumulative current, namely, the high-grade area, the middle-grade area and the low-grade area. The high-grade area covered 4.3 km2 of barriers, mainly distributed in the southwest of Zhengxiang District, northeast and south central of Zhuhui District. The middle-grade area was dominated by pinch area and ecological source area with centrality less than 100, covering an area of about 12.9 km2, mainly distributed in the central part of Zhengxiang District, northeast and south central of Zhuhui District. The low-level area was mainly distributed in south central of Zhuhui District, with 51.8 km2 of residual ecological sources. By coupling InVEST habitat quality analysis module and circuit theory, the ecological security pattern for biological protection was constructed, which provides scientific reference for biological protection.

Middlebox selection optimization via an intelligent framework in software‐defined networking

AbstractSoftware‐defined networking (SDN) has a vital role in network resource utilization. However, it does not provide a comprehensive view of middleboxes (MBs). In this article, we proposed an intelligent dynamic routing framework for performance optimization based on a SDN architecture with a comprehensive view of all network properties. This routing framework also uses the genetic algorithm (GA) for performance improvement. It extracts the CPU, memory, and bandwidth utilization of MBs as dynamic routing parameters. The implemented GA calculates the impact factor (IF) of these parameters to declare the impact of each parameter in network performance. The obtained results show that considering MBs status in flow forwarding improves the tested network's resource utilization by 13, 10, and 7 times compared with hop‐based shortest path first, random path selection, and Round Robin methods, respectively. The results also showed that considering IFs (IFCPU, IFRAM, and IFBW) in routing procedure would improve the network's performance. Therefore, we used the GA to calculate optimal IFs for fairness load balancing and performance optimization. The GA calculates 0.4 and 0.6, for IFCPU and IFBW, respectively. It calculates these IFs only after five iterations. It also showed that we could ignore the RAM utilization parameter in our dynamic routing as our MBs are not memory‐bounded. The simulation results declared that routing with optimal IFs not only improves the network' throughput but also improves load distribution fairness by about 25% compared with routing without the IFs.

Achieving Efficient Routing in Reconfigurable DCNs

With the fast growth of cloud services and network scales, the heavy and highly dynamic traffic demands pose great challenges to the efficient traffic engineering in today's data center networks (DCNs) [21]. The DCN flows can be broadly classified into two main categories: delay-sensitive small flows (e.g., queries or realtime small messages) and throughput-sensitive large flows (e.g., the backup traffic). In general, more than 80% flows in data centers are small flows, while the majority of the traffic volume is contributed by the top 10% large flows [3, 7]. To handle the mixed traffic, today's data centers [1, 14] generally follow the tree-based topologies (e.g., fat-tree) and take the load-agnostic routing strategies based on random path selection (e.g., ECMP1) [14, 19]. Although it is applicable for routing small flows which are highly random, these strategies are likely to route several large flows through the same output link and lead to long-lived congestions [2, 8]. With the limited switch buffer occupied by large flows for a long time, small flows are reported to experience one order of magnitude larger delay, which compromises the performance of DCNs and makes the users suffer [3].

Performance Enhancement for Multihop Harvest-to-Transmit WSNs With Path-Selection Methods in Presence of Eavesdroppers and Hardware Noises

Energy-harvesting-based physical-layer security has become a promising technique, as it not only secures information from eavesdropping without upper layer data encryption but also improves the energy efficiency of wireless networks. However, it imposes new challenges, as adversary parties can overhear the transmission of confidential information between the source and destination via a relay. Therefore, the transmit power of the signals must be large enough for energy harvesting, but it must also be small enough to avoid eavesdropping. This is even more challenging with multihop multipath wireless networks. Motivated by these observations, this paper proposes three innovative protocols, namely, the shortest path selection protocol, random path selection protocol, and best path selection protocol. These will enhance the security of multihop multipath randomize-and-forward cooperative wireless sensor networks under the presence of eavesdroppers and hardware impairment, wherein the source node and relay nodes are capable of harvesting energy from beacon for data transmission. Furthermore, we derive exact closed-form expressions and the asymptotic outage probability for each protocol under multiple eavesdropping attacks. The simulation results validate the theoretical results.

Detection Avoidance and Priority-Aware Target Tracking for UAV Group Reconnaissance Operations

In this paper, we present a novel approach for stationary target tracking in reconnaissance operations with a small UAV group. A reconnaissance mission has multiple competing requirements, such as short scan time and repetitive scanning of the entire area, target recognition, and target tracking. Especially in real-world military reconnaissance scenarios, different types of targets with hostile characteristics exist. The UAVs must scan and track the targets while avoiding detection by enemies. Although small UAVs are unlikely to be detected, they become prone to detection if their path is predictable. To meet these competitive requirements, we propose an attractive pheromone-based cooperative path planning method that makes path prediction almost impossible by ensuring a random path selection mechanism. To avoid detection during target tracking, we implement a new discrete-time tracking scheme with random time intervals and random path planning for multiple UAVs. The proposed model enables a UAV group to sporadically scan the entire area, quickly locate the targets, and simultaneously track the targets based on their priority. In addition, it offers a mechanism that permits the command and control center to balance between reconnaissance and target tracking operations to meet every mission requirement.

An adaptive traffic distribution scheme for CMT based on Lotka-Volterra model in multihomed networks

CMT (concurrent multipath transfer) can increase throughput and transmission efficiency in multihomed networks. However, it is still an important challenge about distributing traffic adaptively into multiple access networks. Based on LV (Lotka-Volterra) model, we propose an adaptive traffic distribution scheme. In the scheme, two competition modes are concluded, multiple S-D (source-destination) streams competition for bandwidth of one path and multipath competition for traffic between each multihomed S-D host pair. Actually, each access network can establish a path for S-D pairs. So, in the first mode, each path is analogous to a predator, and overall traffic in a multihomed host is reducing file transmission time and increasing network throughput in FTP service analogous to prey. Then, each path has to compete for the traffic by path information, e.g., bandwidth and congestion level. In the other one, if several S-D pairs pass through a shared path simultaneously, they will compete for bandwidth of the path. Here, each S-D pair is analogous to a predator, and the bandwidth of the common path is analogous to the prey. At last, compared with other three schemes, uniform traffic distribution, greedy path selection, random path selection in OPNET simulator, the proposed scheme can perform better on

A bio‐inspired OSPF path selection scheme based on an adaptive attractor selection model

SummaryCurrent Internet Protocol routers only support equal cost multi‐path routing, which performs the random path selection or the traffic uniform distribution among equal‐cost paths. In biology, an adaptive attractor selection model is presented to simulate the concentration changes of two kinds of Escherichia coli's mRNA in changing nutrition environments with bistability equations. Inspired by the metabolism behaviors of E. coli, we propose an adaptive path selection scheme Open Shortest Path First‐path selection by attractor selection to dynamically select the transmission path by the real‐time path quality. Here, the mRNA concentration is analogous to the path quality. Then, to reflect the multipath quality, multi‐stability equations are adopted and redesigned. Our scheme consists of two main features. The first one is a redefined path‐activity to indicate multipath transmission goodness, which is inversely proportional to the offset between current path quality and best path quality. And the second one is a new attractor expression of the multi‐stability equations to concretely specify the effect of a stochastic item noise in the equations on the path selection. Compared with the greedy selection and the uniform random selection in file transfer protocol (FTP) service, our scheme gains better performance on reducing file transmission time, traffic throughput, and traffic dropped. Copyright © 2015 John Wiley & Sons, Ltd.

An all-fiber method to measure the wave-particle duality of light

A new scheme with very simple implementations giving obvious experimental results has been demonstrated to reveal the particle and wave duality of light. The scheme demonspates the wave property of light by coherent superposition and the particle property of light by random path selection though a 50/50 beam splitter. Preliminary experiments showed high interference visibility of 99% and the particle nature of light as high as 90% by using a highly attenuated pulsed laser as a single photon source. This scheme displays both the wave and particle nature of light though a simple experimental setup, which makes it a quite promising schem for revealing the property of light.

A performance model of a connection-oriented hypercube interconnection system

Connection-oriented communication is becoming more and more important in the very high-speed (Gbps) communication environment. Under connection-oriented communication, all communication resources at the source (buffers, connection points), in the network (trunks), and at the destination (buffers, processing capacity) must be available before the start of a transmission. This paper presents an analytic model of a direct hypercube interconnection system operating in connection-oriented mode. Due to the high complexity of an exact model of such a system, a tractable approximate model is developed that exploits the system's symmetry to obtain a concise state description. We use our model to evaluate the performance of hypercube interconnection systems. We find that the contention for trunks is small compared to the contention for destination resources. A strategy of checking the resource availability of all waiting connection requests whenever a connection terminates, combined with random path selection, is shown to result in good load/delay characteristics. We further find that the system treats connections of all lengths equally. That is, counterintuitively, connections with shorter paths are not favored over connections with longer paths. We can thus conclude that in addition to good throughput/delay performance, random path selection is fair, and no other measures need be taken to ensure fairness.

Enhanced Congestion Management for Minimizing Network Performance Degradation in OBS Networks

Current global data traffic is increasingly dominated by delay and loss intolerant IP traffic which generally displays a structural self-similarity. This has necessitated the introduction of optical burst switching (OBS) as a supporting optical backbone network switching technology. Due to the buffer-less nature of optical burst switched (OBS) networks, contention/congestion in the core network can quickly lead to degradation in overall network performance at moderate to high traffic levels due to heavy burst loses. Several approaches have been explored to address this problem, notably measures that would minimize burstification delays, congestion, blocking at the same time enhancing end-to-end throughput as well as rational and fair utilization of the links. The aim is to achieve a consistent quality of service (QoS). Noting that congestion minimization is key to a consistent QoS provisioning, in this paper we propose a congestion management approach called enhanced congestion management (ECM) that seeks to guarantee a consistent QoS as well as rational and fair use of available links. It is primarily a service differentiation based scheme that aims at congestion, blocking and latency minimization, by way of combining time averaged delay segmented burstification as well as random shortest path selection based deflection routing and wavelength assignment. Simulation results show that ECM can effectively minimise congestion and at the same time improve both throughput and effective utilization, under moderate to high network traffic conditions. Overall, we show that the approach guarantees a consistent QoS.