Connection Routing Research Articles

Authentication Challenges in a Global Environment

In this article, we address the problem of scaling authentication for naming, routing, and end-entity (EE) certification to a global environment in which authentication policies and users’ sets of trust roots vary widely. The current mechanisms for authenticating names (DNSSEC), routes (BGPSEC), and EE certificates (TLS) do not support a coexistence of authentication policies, affect the entire Internet when compromised, cannot update trust root information efficiently, and do not provide users with the ability to make flexible trust decisions. We propose the Scalable Authentication Infrastructure for Next-generation Trust (SAINT), which partitions the Internet into groups with common, local trust roots and isolates the effects of a compromised trust root. SAINT requires groups with direct routing connections to cross-sign each other for authentication purposes, allowing diverse authentication policies while keeping all entities’ authentication information globally discoverable. SAINT makes trust root management a central part of the network architecture, enabling trust root updates within seconds and allowing users to make flexible trust decisions. SAINT operates without a significant performance penalty and can be deployed alongside existing infrastructures.

A Mathematical Model for Demand Distribution in An Air Transport Network

This article describes the great distance that separates Sardinia from mainland Italy has made the island – the second largest island of the Mediterranean – a marginal and remote region. Its system of ferry links for people travelling to and from Sardinia has such long journey times (8-12 hours) that it is clearly in no way a valid alternative to air transport. It was mainly on the basis of these reasons and with a view to protecting and ensuring the mobility of Sardinian residents that Public Service Obligations (PSO) were imposed on some of the main air routes starting from 2002. Our study is set against this background. It aims to resolve one of the main critical factors that distinguish the PSO network: the shortage of flights on certain routes and the concomitant over-scheduling of others. More specifically, the insufficient scheduling of weekly flights to certain airports, such as Verona and Turin, forces a number of passengers to decide not to travel at all and another part to use connecting flights to Rome/Milan airports or to travel using more than one route, via air or ground transport, with inevitably higher transport costs. The problem was addressed by using a linear scheduling model applied to a network of nodes and arcs representing, respectively, the airports and their connecting routes, and the airport of Cagliari. The decision variables identified were the number of passengers travelling on all of the arcs and the impedance measures associated with the distance travelled by the arcs, represented by the generalized cost of transport. The objective is to determine a network structure which corresponds to the distribution of passengers on the various branches capable of minimizing the total cost. This cost was considered as a useful parameter for comparing the various network scenarios which were obtained by changing the passenger load coefficient and the number of flights. Our study demonstrates that a simple intervention, aimed at the internal reallocation of the flights on the various routes, is able to guarantee categories of users (here divided into business and non-business users) greater access to air transport services. The scenario that more than others is able to improve service efficiency, granting undeniable benefits for all users without having an impact on the costs of air carriers, particularly stands out because it: • Allows access to all network airports through direct flights; • Decongests the Rome and Milan routes

Subjective experiences at the time of peripheral vein needle insertion and route connection in fluid therapy

Subjective experiences at the time of peripheral vein needle insertion and route connection in fluid therapy

Construction of optimal wire sensor network for the area of complex shape

The study is devoted to the problem of designing wire sensory networks for the areas of arbitrary shape. The problem is posed as the construction of the optimum coverage of an area with circles of the equal radii, connected by routes. The purpose is to reduce the total cost of the construction of sensory network to minimum. For developing the effective algorithms in this field, it is necessary to construct the mathematical models, which are based on analytical description of relationships between the objects. The coverage restrictions are described in the work with the help of the phi-functions free from radicals and the new class of functions of belonging of points to areas. For modeling different relationships between the objects we proposed: pseudonormalized functions of belonging of points to areas, functions of quasi-belonging of points to areas, normalized functions of quasi-belonging of points to areas and pseudonormalized functions of quasi-belonging of points to areas. The mathematical model, constructed with the application of new means of modeling, is in the general case the problem of the non-smooth optimization. The strategy of the solution, which includes the algorithm for generation of starting points from the area of permissible solutions of the problem and the optimization procedure, is proposed. Starting points are constructed with the help of heuristic methods. The construction of the starting point includes the stage of the construction of circular coverage and the stage of trace routing. The procedure of the search for the local extrema, which reduces the problem of non-smooth optimization to the sequence of problems of nonlinear programming, was proposed. As a result of the conducted study, the approach, which makes it possible to use contemporary NLP-solvers in the search for the local-optimum solutions of the joint problem of circular coverage and trace routing of wire connections, was proposed. The proposed approach can be easily adapted to solving other problems of covering areas with identical circles. In particular, the problem of the minimization of radii of covering circles for areas with the curvilinear boundary was solved.

Manage the Traffic Load for Reducing Power Consumption in Wireless Sensor Network with Mobile Sink

Most important issues that scientific research seeks to solve the limited power, since consuming battery energy comes from communication among sensor nodes in wireless sensor network. Anew method for traffic management with load balancing in wireless sensor network (WSN) has been proposed using backbone update messages. The method of reducing the number of connection and maintain these connections by nearby Virtual Backbone (VB) sensors or identify the new VB for maintaining a multi-connections, attach these nodes with new VB to maintain the node connections, analyzed the quality of proposed solutions that implemented with path of sink nodes. Finally, simulation of managing the traffic for sample network focusing on substantial savings by controlling the power by balancing the routing of available connections.

Position Based Seamless Connectivity for Vehicular Ad Hoc Networks

Vehicular ad hoc networks is one of the emerging fields in todays era. Both industry and academia are focusing their interest in coping up with the upcoming challenges in this field for providing enhance safety and infotainment services to the passengers. A heterogeneous wireless network architecture has been proposed to achieve communication among vehicles or communication between vehicles and infrastructure at any time and any where for efficient routing which improves the connectivity issues in vehicular ad hoc networks. A novel position based routing algorithm called PB-SCR (Position Based Seamless Connectivity Routing) has also been proposed to offer seamless connectivity to the passengers travelling on rural highways through heterogeneous wireless network architecture. This algorithm has been simulated using NS-2 simulator and evaluated the performance in terms of packet delivery ratio, end-to-end delay, and average path length. The results of PB-SCR are compared with AODV and GPSR routing protocols and shows significant performance improvement.

Simulating urban growth by emphasis on connective routes network (case study: Bojnourd city)

Development of urban construction and ever-increasing growth of population lead to landuse changes especially in agricultural lands, which play an important role in providing human food. According to this issue, a proper landuse planning is required to protecting and preserving the valuable agricultural lands and environment, in today’s world. The prediction of urban growth can help in understanding the potential impacts on a region’s water resource, economy and people. One of the effective parameters in development of cities is connective routes network and their different types and qualities that play an important role in decreasing or increasing the growth of the city. On the other hand, the type of the connective routes network is an important factor for the speed and quality of development. In this paper, two different scenarios were used to simulate landuse changes and analyzing their results. In first scenario, modeling is based on the effective parameters in urban growth without classification of connective routes network. In the second scenario, effective parameters in urban growth were considered and connective routes were classified in 6 different classes with different weights in order to examine their effect on urban development. Simulation of landuse has been carried out for 2020–2050. The results clearly showed the effect of the connective routes network classification in output maps so that the effect of the first and second main routes network in development, is conspicuous.

Augmenting Path Algorithm for Routing Telephone Calls Problem

This paper deals with the optimization problem that decides the routing of connection between multi-source and multi-sink. For this problem, there is only in used the mathematical approach as linear programming (LP) software package and has been unknown the polynomial time algorithm. In this paper we suggest the heuristic algorithm with <TEX>$O(mn)^2$</TEX> time complexity to solve the optimal solution for this problem. This paper suggests the simple method that assigns the possible call flow quantity to augmenting path of (<TEX>$s_i,t_i$</TEX>) city pair satisfied with demand of (<TEX>$s_i,t_i$</TEX>). The proposed algorithm can be get the same optimal solution as LP for experimental data.

Neighborhood-based interference minimization for stable position-based routing in mobile ad hoc networks

For efficient communication in a mobile ad hoc network (MANET), dealing with interference while performing concurrent multi-hop routing is of great importance. By establishing an interference-aware route we can potentially reduce the interference effects in the overall wireless communication, resulting in improved network performance. Typically, mobile devices, represented by nodes in a MANET, broadcast in a limited shared media. Using both routing and scheduling mechanisms for wireless transmissions can reduce both redundancy and communication interference. We study communication interference problems in the context of maintaining stable connection routes between mobile devices in MANETs. This paper presents extensions of our previously studied position-based stable routing protocol Greedy-based Backup Routing Protocol with Conservative Neighborhood Range to maintain connection stability while minimizing the number of corrupted packets in the presence of more general communication interference. Simulation results demonstrate the effectiveness of the new protocols.

ANALYSIS ON THE CHARACTERISTICS OF DENSE BUSINESS AREAS OF CENTRAL CITY AREA FROM THE RELATION WITH URBAN STRUCTURE

In the early seventeenth century, the beginning of Edo period in Japan, almost all cities in Japan were constructed castle town, called JO-KA-MACHI in Japanese. Its forms are unique and diverse. Since the late nineteenth century, the train and derived infrastructures were incorporated into the old castle town structure, thus, various mutual relationships have been formed between stations and castle districts. Currently, City centers have maintained its traditional cultural elements, but the other hand, have changed gradually in accordance with the urban growth and its activities. Such urban structure of castle town plays an important role on re-activation strategies and selection of the re-activation areas. The purpose of this study is to clarify the positional relationship between dense project areas and the urban structure in Japanese castle-town cities. The study analyzed 9 cities by means of GIS kernel density estimation. By using official project volume and number of projects data, it is possible to analyze dense project areas as well as their relation with the former urban structure. As a result, the study found that distribution patterns by project amount and by project volume are different. The research found 4 characteristic types of density project areas. Besides, by analyzing these types in relation to the physical urban structure 3 form distribution patterns were found. -In the cases when the station and castle district are close, density project areas concentrate around them. -When the station and the castle district distant but connected by axis, two different patterns can be found: - Density project areas are localized on this connection route. - Density project areas are dispersed and there is no strong relation to the axis. -Finally, when there is not a clear connection, density project areas appear dispersed without apparent clear criteria. The analysis made clear the actual connection between density project areas and the urban structure with the following conclusions: 1. The study developed a method for analyzing the correspondence between urban structure and density project areas involved in the activation of central city area by establishing a way to express the stage of the density focusing on the volume and the number of business. 2. The distribution of dense project areas varies in accordance to the diversity of each urban structure. The research found diverse patterns of distribution and accumulation of projects according to the urban structure and features of central city areas. Further research should verify how the characteristics of density project areas correspond to the urban structure, and how this method can be applied for the evaluation of the regeneration strategy in the central city areas.

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.

Multipath Load Balancing Routing for Internet of Things

In the next-generation technology, Internet of Things (IoT), billions of smart objects will communicate with one another to make human lives more convenient. IoT is based on wireless sensor network (WSN), and Zigbee is one of the most popular WSN protocols. A mature IoT environment involves heavy WSN data transmission causing bottleneck problems. However, Zigbee’s AODV routing stack does not have load balance mechanism to handle bursty traffic. Therefore, we develop Multipath Load Balancing (MLB) Routing to substitute Zigbee’s AODV routing. Our proposed MLB consists of two main designs: LAYER_DESIGN and LOAD_BALANCE. LAYER_DESIGN assigns nodes into different layers based on node distance to IoT gateway. Nodes can have multiple next-hops delivering IoT data. All neighboring layer nodes exchange flow information containing current load, used by LOAD_BALANCE to estimate future load of next-hops. With MLB, nodes can choose the neighbors with the least load as the next-hops and thus can achieve load balance and avoid bottlenecks. Compared with Zigbee’s AODV and multipath version AODV (AOMDV), experiment results demonstrate that MLB achieves better load balance, lower packet loss rate, and better routing connectivity ratio in both grid and random uniform topologies. MLB provides a more convincing routing solution for IoT applications.

Large-scale transit itinerary planning under uncertainty

In this paper, we study the transit itinerary planning problem with incorporation of randomness that arises in transit vehicle arrival/departure and passenger transfer. We investigate two approaches to address the uncertainty: a minmax robust approach and an expectation-based probabilistic approach. We adapt a two-phase framework to mitigate computational challenges in large-scale planning problems. In phase I, we compute candidate route connections offline and store them into a database. Although expensive computation is required in phase I, it is typically performed only once over a period of time (e.g., half a year). Phase II takes place whenever a request is received, for which we query candidate route connections from the database, build a stochastic shortest-path model based on either approach listed above, and solve the model in real time. With phase I, computational requirement in phase II is substantially reduced so as to ensure real-time itinerary planning. To demonstrate the practical feasibility of our two-phase approach, we conduct extensive case studies and sensitivity analyses based on a large real-world transit network.

GIS-based cost distribution analysis of new consumer connections to an urban power grid

In this paper, we propose a method of cost distribution analysis of new consumer connections to a city power grid by accounting for spatial restrictions and characteristics of existing networks. In practice, the calculation of connection costs for each new consumer includes the network design and financial expenditure. We suggest that connection costs should be calculated for the whole city based on the normative parameters at the stage when the object location is selected by investors and when power grid development is planned by power companies. The proposed method enables the modeling of new power line connection routes from every parcel of city land to possible points of connection to the operating networks based on the raster design of the area. The optimal path is chosen by one criterion consisting of two components: the costs of both laying new power lines and providing sufficient power reserve in the chosen network connection point. Realized as a computer program, the method has been used to calculate the costs of connections to low-voltage power lines.

Simulation analysis of factors affecting air route connection in China

In order to explore the impacts of various factors on air route connection, a probability model is constructed to simulate the Chinese airline network (CAN) in 2010, and the influences of tertiary industry output, degree and the spatial distance between two navigable cities on the analog results are discussed. Our research shows that, the opening of an air route is not completely determined by the potential air passenger flow of it, although the latter is playing a leading role. In addition, the connection probability of an air route is significantly affected by the tertiary industry outputs and degrees of corresponding two navigable cities, but little influenced by the spatial distance between them. Moreover, scale economies effect obtained from the increasing of degree is apparently greater than that brought by the developing of social economy, so CAN is more inclined to evolve into a hub-and-spoke network.

Metric inequalities for routings on direct connections with application to line planning

We consider multi-commodity flow problems in which capacities are installed on paths. In this setting, it is often important to distinguish between flows on direct connection routes, using single paths, and flows that include path switching. We derive a feasibility condition for path capacities supporting such direct connection flows similar to the well-known feasibility condition for arc capacities in ordinary multi-commodity flows. The condition can be expressed in terms of a class of metric inequalities for routings on direct connections. We illustrate the concept on the example of the line planning problem in public transport and present an application to large-scale real-world problems.

Locating the Indian Ocean: notes on the postcolonial reconstitution of space

The networks of human relation that define the Indian Ocean region have undergone significant reconfiguration in the last half-century. More precisely, the economic insularity of the region has diminished while the postcolonial nation has both restricted movement and reoriented the political imaginations of people along the rim. At the same time, the Indian Ocean has been revivified as a unit of social exchange and analysis, particularly since the end of the Cold War. This article explores the meaning of Indian Ocean Africa in the context of a multipolar world by focusing on how the dictates of nations have transformed the region and how the petroleum economy as well as shifting means of social engagement have engendered new linkages. The essay argues that although the postcolonial era affected the closure of certain historical routes of connectivity, relationships structured by contemporary nations and air travel, among other things, have encouraged perceptions of regional coherence. What we might term basin consciousness has begun to reverse the introverted politics of the early postcolonial era and animate the Indian Ocean as an idea.

GRAPPE : a system for determining optimal connecting route to target person based on mutual intimacy index

Recently, the growth of social network service (SNS, Facebook) has required the search technique to utilize its distinctive characteristic which links people to people. This paper discusses the design and implementation of GRAPPE which suggests the ranked list of optimal connecting routes between two people by interaction like SNS, phone calls, texts, mails. It is based on mutual intimacy index (MII) which indicate how closely two people are related. MII is calculated periodically when a user interact with other person by smartphone. In this study, we propose a simple two-ended search method for finding optimal routes between a source person and a destination person. For the real-time service it searches optimal path within 3 step-away relationship in human network that is effective in real life while existing services in SNS usually provide one-ended search on entire paths. Furthermore, we also use the pruning technique for efficient execution time.

Using Synoptic Systems' Typical Wind Trajectories for the Analysis of Potential Atmospheric Long-Distance Dispersal of Lumpy Skin Disease Virus.

Lumpy skin disease virus (LSDV) is an infectious, arthropod-borne virus that affects mostly cattle. Solitary outbreaks have occurred in Israel in 1989 and 2006. In both years, the outbreaks occurred parallel to a severe outbreak in Egypt, and LSDV was hypothesized to be transmitted from Egypt to Israel via long-distance dispersal (LDD) of infected vectors by wind. The aim of this study was to identify possible events of such transport. At the first stage, we identified the relevant synoptic systems that allowed wind transport from Egypt to Israel during the 3months preceding each outbreak. Three-dimensional backwards Lagrangian trajectories were calculated from the receptor sites in Israel for each occurrence of such relevant synoptic system. The analysis revealed several events in which atmospheric connection routes between the affected locations in Egypt and Israel were established. Specifically, during the 1989, Damietta and Port Said stand out as likely sources for the outbreak in Israel. In 2006, different locations acted simultaneously as potential sources of the outbreak in Israel. These locations were situated in the Nile delta, the Suez Canal and in northern Sinai. The analysis pointed out Sharav low and Shallow Cyprus low to the North to be the most likely systems to enable windborne transport from Egypt to Israel. These findings are of high importance for the analysis of the risk of transmission of vectorborne viruses in the eastern Mediterranean region.

Optimal vehicle routing with lower and upper bounds on route durations

This article is concerned with the problem of finding optimal vehicle routes to minimize the overall travel time, with constraints on the minimum and maximum amount of time spent on each route. The problem extends previous work on the distance‐constrained vehicle routing problem by introducing lower bounds on route durations to ensure that the resulting routes are balanced. The article also explicitly addresses the situation where a solution is artificially balanced as a result of inoptimal orders of visits. The article describes alternative ways in which the restrictions on route connectivity, duration, and artificial balancing can be formulated, and introduces an exact algorithm based on cutting planes and mixed‐integer linear programming. To the best of our knowledge, this is the first exact algorithm proposed for such a problem that explicitly addresses artificially balanced routes. Computational results are presented for three versions of the exact algorithm using TSPLIB instances. © 2015 Wiley Periodicals, Inc. NETWORKS, Vol. 65(2), 166–179 2015