Routing Management Research Articles

A Review on Deployment Architectures of Path Computation Element using Software Defined Networking Paradigm

In traditional Generalized Multi-Protocol Label Switching (GMPLS), wide variety of functionalities like, GMPLS signaling GMPLS routing and link management increased the computational complexity of a single GMPLS network node. In concern with this, in order to provide the best paths by concerning effective utilization of network resources and better quality of transmission, a dedicated Path Computation Element (PCE) has been introduced. Software Defined Networking (SDN) is a new paradigm that decouples the network control from the data plane. With Software Defined Networking, the design, build and manage of networks can be made cost effective and dynamic manner, by transforming the traditional networks into open and programmable networks. The objective of this paper is to provide different architectural models of path computation element using Software Defined Networking paradigm. Using these deployment models, a network operator can manage and operate both the circuit switching and packet switching networks, thereby reduce capital expenses as well as operational expenses.

Variables influencing law enforcement off-road route proliferation on an arid site

Off-road vehicle impacts are a common and often severe form of disturbance in arid and semiarid lands around the world. Determining the underlying impetus behind the generation of new routes may allow better management of their impacts. We hypothesized that six variables may have predictive power: distance from slopes greater than 34% (impassible slopes), distance from unauthorized routes, slope, view from authorized routes (driving to places that cannot be seen), distance from authorized routes, and elevation. Route proliferation in the San Cristobal Valley, Arizona, USA, a site with border enforcement travel but without recreational use, was measured using remotely sensed imagery and 7014km of unauthorized routes were identified. Two variables were significant (p<0.05, R2=0.57) predictors of route proliferation: distance from slopes greater than 34% and distance from unauthorized routes. For each kilometer distant from the slope, route density decreased by a factor of two and, for each 100m distant from unauthorized routes, route density decreased by a factor of five. Slope, view from authorized routes, distance from authorized routes, and elevation were also tested but were not significant and were not included in the model. Unauthorized route density appears at least partially predictable and analysis of geographic variables may offer a way to prioritize route management decisions.

Combined ship routing and inventory management in the salmon farming industry

We consider a maritime inventory routing problem for Norway’s largest salmon farmer both producing the feed at a production factory and being responsible for fish farms located along the Norwegian coast. The company has bought two new ships to transport the feed from the factory to the fish farms and is responsible for the routing and scheduling of the ships. In addition, the company has to ensure that the feed at the production factory as well as at the fish farms is within the inventory limits. A mathematical model of the problem is presented, and this model is reformulated to improve the efficiency of the branch-and-bound algorithm and tightened with valid inequalities. To derive good solutions quickly, several practical aspects of the problem are utilized and two matheuristics developed. Computational results are reported for instances based on the real problem of the salmon farmer.

Homogeneity and Activeness of Crowd on Aged Pedestrian Dynamics

An aging population is bringing new challenges to the management of escape routes and facility design in many countries. In this paper the movement properties of middle- and old-aged adults are studied with series of single-file movement experiments under laboratory conditions. The fundamental diagrams for two different groups of pedestrians and time-space diagrams are compared. For the groups with different composition and status, the fundamental diagrams are totally different but maintain the same trend. Active crowd leads to inhomogeneous pedestrian flow but higher flow rate, while inactive pedestrians prefer to keep pace with others or keep larger personal space, which leads to more jams and stop-and-go waves. Density and inhomogeneous of speed do not always play main roles on the appearance of stop-and-go.

Reinforcement Learning for Routing and Spectrum Management in Cognitive Wireless Mesh Network

Cognitive radio networks (CRNs) can provide a means for offering end-to-end Quality of Service (QoS) required by unlicensed users (secondary users. SUs). The authors consider the approach where licensed users (primary users, PUs) play the role of routers and lease spectrum with QoS guarantees for the SUs. Available spectrum is managed by the PU admission and routing policy. The main concern of the proposed policy is to provide end-to-end QoS connections to the SUs. Maximizing gain is the key objective for the PU. In this paper, the authors propose a novel resource management scheme where reinforcement learning (RL) is used to drive resource management scheme. The derived scheme helps PUs to adapt to the changes in the network conditions such as traffic load, spectrum cost, service reward, etc, so that PU's gain can continuously be optimized. The approach integrates spectrum adaptations with connection admission control and routing policies. Numerical analysis results show the ability of the proposed approach to attain the optimal gain under different conditions and constraints.

Sustained Flow Index: Stochastic Measure of Freeway Performance

Research into the operation of traffic flow at high volumes reveals that the capacity of freeways is not a fixed number but is rather a random variable. Since traditional operational performance measures for the analysis of traffic flow on freeways typically disregard the randomness of capacity, new approaches to make use of the concept of randomness for freeway operation analysis are required. To address that need, this paper introduces a new indicator of freeway performance based solely on a stochastic approach to capacity computation. With this new indicator, the maximum reliable volume that can be carried by a freeway over prolonged time periods was derived from parameters of capacity distribution functions. The breakdown probability corresponding to the optimum volume can be used to select a single value from the capacity distribution function. To explore the empirical relationship between expected values of capacity and the optimum volumes calculated from this new computational process, flow data from several German freeway sections were analyzed. To illustrate the application potential for a sustained flow index, this paper also discusses the bases for increasing the effectiveness of ramp metering and vehicle routing management techniques.

Encounter based Routing and Buffer Management Scheme in Delay Tolerant Networks

Tolerant Networks (DTNs) are one of the most interesting evolutions of MANETs where frequent disconnection of networks is there so that end to end path not establish between source to destination. When seeing routing protocols of DTNs, a forwarding and buffer management are important to be considered for successful message delivery. Based Routing (EBR) which increase delivery ratio by decreasing overhead and delay using the encounter value of the nodes. EBR takes the average Encounter Value (EV) of the node and decide that how many copies of the message to be sent to the other nodes. Higher the EV value, the node will get more number of message copies. We propose the modified EBR which optimizes the performance of the existing EBR. We consider the change of rate of EV with respect to time and then intelligently decide the number of replicas to be sent to the encountered nodes. The modified EBR scheme performs better in terms of delivery ratio than the existing EBR protocol. We also propose the buffer management policy using EV of the node to decide the dropping of the message in the Epidemic routing protocol. These schemes are HEV (High Encounter Value) and LEV (Low Encounter Value) and they are compared with the existing traditional policies such as LIFO and FIFO. The simulation results show that our proposed dropping policy improves the overhead ratio, delivery delay and hop count metrics than the existing ones.

Implementation of Forward Pointer-Based Routing Scheme for Wireless Mesh Network

Because of the advantages of flexibility and ease of deployment, wireless mesh network (WMN) has become a promising technology for providing internet access to the users. For implementation of WMN, IEEE 802.11s standard has been developed. To route the packets from source to destination, IEEE 802.11s uses a routing algorithm named hybrid wireless mesh protocol (HWMP). But IEEE 802.11s does not support mobility of external stations. For solving this problem, many mobility management schemes such as: MEsh networks with MObility management, mesh mobility management (M 3), iMesh, Smesh and WMM have been proposed. But, none of the schemes are integrated with HWMP. In this paper, an enhanced form of HWMP named forward pointer-based routing (FPBR) has been introduced. Numerical analysis of both HWMP and FPBR has been carried out. HWMP and FPBR have been simulated in NS2, and their performances have been compared. Simulation results show that by varying number of external stations, on average FPBR outperforms HWMP by 93.9, 49, 86.5 and 16.4 % in terms of normalized routing overhead, throughput, handoff cost and end-to-end delay, respectively. With variation in data transmission rate of external stations, on average FPBR outperforms HWMP by 96, 10, 87 and 12 % in terms of normalized routing overhead, throughput, handoff cost and end-to-end delay, respectively. With variation in maximum movement speed of the external stations, FPBR outperforms HWMP by 94 and 97 % in terms of handoff cost and normalized routing overhead. Finally, the number of route management packets per handoff, obtained from both numerical analysis and simulation results has been compared.

An optimization approach for real time evacuation reroute planning

This paper addresses evacuation route management in the case of incidents arising during an evacuation and aims to minimize further delays they may cause. An evacuation reroute planning approach is developed for decision makers to utilize alternative routes in real time for the evacuees whose evacuation paths are affected by an incident during the evacuation process. Assuming that real time traffic information is available, a preprocessing algorithm is performed to update the evacuation networks. A multi-commodity network flow optimization model is then utilized to develop alternative paths and corresponding flow rates. Due to the underlying optimization model being a mixed integer nonlinear programming formulation, a linear reformulation of the model is developed to improve the computational performance. In the numerical results, the performance of the proposed decision making tool is tested using a case study.

Trusted Tree-Based Trust Management Scheme for Secure Routing in Wireless Sensor Networks

The unique characteristics of wireless sensor networks make them susceptible to the attacks. The secure scheme is considered in designing the routing protocol and algorithm. The cryptography and authentication secure technology can defend the external attacks but have no way to protect the network when the internal attacks occur. However, the trust management scheme with attack-resistance and robustness can efficiently detect the internal attack. On the condition of defending the attacks, it is also an issue that the trust management scheme aids routing algorithm to improve the security and performance. In this paper, we proposed a Trusted Tree-based trust management for secure routing in wireless sensor networks. The common attacks are firstly analyzed. And then the dynamic time window is designed in the distributed trust model with the detection of direct trust and indirect trust. Based on the trusted nodes, Trusted Tree is constructed. And the path quality of nodes in Trusted Tree is used as the gradient for routing. Finally, we add Trusted Tree-based trust management into the QoS based routing protocol and algorithm. Experimental results show that the QoS based routing algorithm with Trusted Tree has better performance and security.

QoS-Aware Inter-Domain Multicast for Scalable Wireless Community Networks

Wireless community networks (WCNs) have emerged as a cost-effective ubiquitous broadband connectivity solution, offering a wide range of services in a given geographical area. QoS-aware multicast over WCNs is among the most challenging issues and has attracted a lot of attention in recent times. The existing multicast schemes in WCNs suffer in terms of several key performance metrics, such as, latency, jitter and throughput, particularly in large-scale networks. Consequently, these schemes cannot accommodate the desired performance levels, especially when dealing with high-bandwidth applications that require efficient gateway-based management. To fill in this gap, a new strategy for supporting QoS-aware multicast in large-scale WCNs is proposed in this paper. Specifically, a new Gateway based Multi-hop Routing algorithm (GMR) is firstly proposed to enhance the routing management capability of the network. Built upon GMR, a new Multicast Gateway Multi-hop Routing algorithm (MGMR) is devised to cope with high-bandwidth applications in WCNs. The MGMR is the first of its kind that considers both the capability of gateway-based management and the requirements of high-bandwidth applications. Extensive simulation experiments and performance results demonstrate the superiority of both GMR and MGMR when compared to other methods under various operating conditions.

Resilience support in software-defined networking: A survey

Software-defined networking (SDN) is an architecture for computer networking that provides a clear separation between network control functions and forwarding operations. The abstractions supported by this architecture are intended to simplify the implementation of several tasks that are critical to network operation, such as routing and network management. Computer networks have an increasingly important societal role, requiring them to be resilient to a range of challenges. Previously, research into network resilience has focused on the mitigation of several types of challenges, such as natural disasters and attacks. Capitalizing on its benefits, including increased programmability and a clearer separation of concerns, significant attention has recently focused on the development of resilience mechanisms that use software-defined networking approaches. In this article, we present a survey that provides a structured overview of the resilience support that currently exists in this important area. We categorize the most recent research on this topic with respect to a number of resilience disciplines. Additionally, we discuss the lessons learned from this investigation, highlight the main challenges faced by SDNs moving forward, and outline the research trends in terms of solutions to mitigate these challenges.

A survey on software defined networking and its applications

Software defined networking (SDN) achieves network routing management with logically centralized control software that decouples the network data plane from the control plane. This new design paradigm greatly emancipates network innovation. This paper introduces the background of SDN technology with its design principles, explains its differentiation, and summarizes the research efforts on SDN network architecture, components and applications. Based on the observation of current SDN development, this paper analyzes the potential driving forces of SDN deployment and its future trend.

Development of an Adaptive Routing Mechanism in Software-Defined Networks

The purpose of this work is to develop a unitary mechanism of adaptive routing of different kinds, basing on the current requirements on the quality of service. The software configuration of a network is the technology of the future. The trend in communication systems constantly confirms this fact. However, the application of this technology in its current form is justified only in large networks of technology giants and telecom operators. Today we have a large number of dynamic routing protocols to route big volume traffic in communication networks. Our task is to create the solution that can use the opportunities of each node to make a decision on the transmission of information by all possible means for each type of traffic. Achieving this goal is possible by solving the problem of the development of generalized metrics, which details the links between devices in the network, and the problem of establishing a framework of adaptive logical network topology (route management) to ensure the quality of the whole network in order to meet the current requirements on the quality of a particular type service.

Development of Physiological Parameters Gateway for Medical IOT Ward

Internet of things (IOT) gateway is an important part in all kinds of IOT applications within healthcare Indus- try. To meet with the needs from wireless transfer and management of physiological parameters in hospital, a kind of IOT gateway for physiological parameters service is designed. Carrier sensing technology, automatic networking technology, and multi-thread programming technology are adopted to design and manufacture the gateway. A hardware gateway and a physiological parameters gateway server with functions of protocol translation, routing management, and data security control are designed to deal with different needs of the sensor network in the Medical IOT Ward. The physiological pa- rameters gateway, which is the key application device in medical IOT ward, is designed to fulfil intelligent collection and comprehensive convergence of daily physiological parameters. The medical IOT ward simplifies the work of physiologi- cal parameters collection which is used to be finished manually, and provides reliable security assurance for the patients' daily care. It will has high value in clinical application.

Improving QoS Routing in Hybrid Wireless Mesh Networks, Using Cross-Layer Interaction and MAC Scheduling

Abstract Delivering Quality of Services (QoS) for cooperative Wireless Mesh Networks (WMN) is an important issue when enabling heterogeneous wireless technologies on the client side. A standard approach for satisfying the QoS requirements of different wireless clients appears to be a complex task due to the capacity variations. In addition to the routing layer, the information at the lower layers, such as Physical and Medium Access Control (MAC) layers must be considered for providing the QoS guarantee. The strength of a signal received from heterogeneous clients at the physical layer and the coupled network capacity at the MAC layer plays an important role in the efficient path assignment and time scheduling management for routing. Therefore, this paper proposes an Adaptive Multipath-Dynamic Source Routing (AM-DSR) protocol. It supports Cross-Layer Interaction (CLI) for path assignment and MAC scheduling mechanism for slot assignment to improve the mesh backbone performance for providing multimedia services to various wireless clients in a hybrid WMN. The proposed strategy measures the cross-layer parameter, such as the network capacity, using the Signal to Noise Ratio (SINR) and assigns a route that maximizes the efficiency of the multimedia services. Finally, the performance evaluation shows that the proposed cross-layer based AM-DSR protocol provides efficient QoS support for the mesh backbone enabling connections to multiple clients.

An Integrated Model Predictive Scheme for Baggage-Handling Systems: Routing, Line Balancing, and Empty-Cart Management

This brief proposes a new strategy for integrated control of baggage-handling systems (BHS). Three main control issues in BHS, namely, routing and scheduling, empty-cart management, and line balancing, are identified and a combined control approach based on model predictive control is proposed to tackle these issues in an optimal way. It is shown that the control approach can be formulated as a linear programming problem, which can be solved very efficiently, and hence the proposed approach can be extended to large-scale BHS. We illustrate the applicability and performance of the proposed approach by a case study, and we compare the results with the state-of-the-art method currently used for BHS.

On the optimal management of the closed-loop management in safe practice of nursing teaching in private hospitals

Objective To study the optimal management of the closed-loop management in safe practice of nursing teaching in private hospitals. Method Through analyzing the causes and problems during the teaching of nursing adverse events, the closed-loop management in safe practice of nursing teaching was investigated, including the closed-loop management team, implementation cycle and range, etc. Totally 100 teachers and 220 students were chosen in 27 clinical teaching departments of our hospital during January 2013 and March 2014. The teachers were divided into experimental group (n=50) and the control group (n=50). The closed-loop management model was applied in experimental group while routing management was applied in control group. At the same time, 220 students' behavior in experimental group was compared before and after the closed-loop management. Through the evaluation of nursing teaching' safe hidden trouble and questionnaire survey, the nursing teaching of both groups were safe. SAS 9.2 was applied to do statistical analysis and non-parametric Wilcoxon Fisher exact test and χ2 test were used. Results The number of teachers' operating key points in experimental group was significantly higher than the control group, with statistically significant differences (46 vs. 15) (P=0.000). The safety hazard times of nursing teaching were 38 and 8 respectively before and after the closed loop management, and the difference was statistically significant (P=0.000).In addition, the comparison before the students' implementing the check system, hospital safety index patients and regulation for technical operations and hospital infection was significant after the closed-loop management (P<0.01 for all). Conclusion The full implementation of the closed-loop manage-ment, effective tracking and prevention in place, can optimize the safety management of nursing teaching. Key words: Closed-loop management; Private hospital; Teaching safety management; Teachers; Students

Spatial and environmental patterns of off-road vehicle recreation in a semi-arid woodland

Outdoor recreation is a widely recognized cultural ecosystem service. Ensuring that appropriate, high quality recreation opportunities are available requires, among other factors, knowledge of the environmental preferences of recreation users and spatial indicators of where those environmental features exist on the landscape and offer the potential to meet recreation goals. Diverse types of outdoor recreation exist, and different forms of recreation may be associated with different environmental features. The focus of this study is off-road vehicle (ORV) recreation. We demonstrate how readily available spatial environmental datasets, including high resolution image data provided within GoogleEarth, can be used to develop a cost-effective, objective indicator of ORV recreation across a landscape, which can inform management to provide desired recreation opportunities while protecting ecologically sensitive areas.ORV recreational tracks were delineated from GoogleEarth imagery throughout our study area in the Great Western Woodlands of Western Australia. In this region, ORV use is a popular recreation activity and a growing concern of conservation organizations, but is not yet actively managed. Most recreational ORV tracks in the study area are informal and user-created. Mapped ORV recreation tracks were used to model and map the environmental associations of ORV recreation. The pattern of existing tracks indicated associations between recreation and noteworthy environmental amenities in the study area such as the shores of salt lakes and rock outcrops with high ecological and cultural value. However, one of the most important determinants of ORV track presence was accessibility, especially proximity to a road. Access infrastructure, such as proximity to roads, is often used to proxy demand and use in expert-based spatial assessments of ecosystem services. The results of our empirical model underscore the importance of incorporating patterns of both supply (i.e., desired natural amenities) and demand (i.e., access) into ecosystem service assessments. In addition, when integrated with maps of environmental sensitivity and more detailed information about human use, the predictive map of areas providing potential recreation experiences can be used for comprehensive spatial planning of sustainable ORV recreation. One possibility suggested by our results is that careful planning and management of access routes may be an effective means to achieve sustainable ORV recreation.

Spatial decision support system for the route management for milk collection from dairy farms

In this research, a new spatial decision support system (SDSS) was developed, which solves the milk collection problem in two stages. First it applies an algorithm, employing heuristic techniques, generating solutions in a short period of time. In a second step, a graphic interface has been developed, which allows interaction and changes to be carried out in a rapid and intuitive way on the routes generated by the routing algorithm. The route manager can also carry out a broad range of “What if” simulations to find the solution that minimizes cost.With the use of this tool, significant savings have been obtained in terms of the collection time and kilometers covered by freight, while still keeping the current fleet of vehicles. Sensitivity analysis shows that the total cost of the process is more sensitive to increasing truck capacity than duplicating vehicle working shifts. The existence of farms with difficult access increases the collection costs substantially.