Evaluation on Rate Adaptation Algorithm Applied For Wireless Mesh Network

 Penelitian ini mengevaluasi beberapa algoritma rate adaptation untuk mendapatkan algoritma yang paling sesuai digunakan pada jaringan wireless mesh network (WMN). Pada beberapa penelitian terdahulu, evaluasi terhadap algoritma-algoritma rate adaptation masih terbatas pada kinerja algoritma rate adaptation secara umum dan pada jaringan yang sederhana, sedangkan untuk penelitian ini dikhususkan pada kenaikan nilai throughput yang disebabkan oleh penerapan algoritma rate adaptation dan pada jaringan yang lebih kompleks yaitu WMN. Algoritma rate adaptation yang dipilih untuk dievaluasi adalah algoritma-algoritma yang sudah umum digunakan, yaitu algoritma auto rate fallback (ARF), adaptive auto rate fallback (AARF) dan collision aware rate adaptation (CARA). Evaluasi dilakukan melalui serangkaian simulasi menggunakan software NS-3 untuk mengetahui nilai throughput yang dihasilkan oleh masing-masing algoritma pada kondisi jaringan WMN dengan jumlah node yang berbeda-beda. Hasil evaluasi menunjukkan bahwa kinerja algoritma CARA mampu melampaui kinerja dua algoritma lainnya, yaitu ARF dan AARF untuk kondisi jaringan WMN yang kompleks (grid 4x5 dan 5x5).This paper attempts to evaluate some rate adaptation algorithms in order to find the most suitable algorithm to be used in the wireless mesh network (WMN) environment. In some previous researches, the evaluation on these algorithms is still limited on a general rate algorithm performance and in a simple network, while this research was devoted on the increase in throughput value due to the implementation of rate adaptation algorithm and in a more complicated network, WMN. The rate adaptation algorithms evaluated in this research were auto rate fallback (ARF), adaptive auto rate fallback (AARF) and collision aware rate adaptation (CARA), which are the most commonly used algorithm. The evaluation was carried out through a series of simulation using NS-3 software to find out the throughput value resulted by each algorithm. The evaluation result showed that the CARA algorithm outperformed two other algorithms, i.e. ARF and AARF, for a complex WMN condition (grid 4x5 and 5x5).Keywords: Jaringan WMN, throughput, rate adaptation algorithm, CARA, NS-3ReferensiCapone, A. Carello, G. 2006. Scheduling optimization in wireless mesh networks with power control and rate adaptation. In  Sensor and Ad Hoc Communications and Networks, 2006. SECON'06. 2006 3rd Annual IEEE Communications Society on, (Vol. 1, pp. 138-147). IEEE.     Senthilkumar, D. Krishnan, A. 2010. Throughput analysis of IEEE 802.11 multirate WLANs with collision aware rate adaptation algorithm. International Journal of Automation and Computing, 7(4), 571-577.Lacage, M., Manshaei, M. H., Turletti, T. 2004, October. IEEE 802.11 rate adaptation: a practical approach. In Proceedings of the 7th ACM international symposium on Modeling, analysis and simulation of wireless and mobile systems (pp. 126-134). ACM.Kim, J., Kim, S., Choi, S., Qiao, D. 2006, April. CARA: Collision-Aware Rate Adaptation for IEEE 802.11 WLANs. In INFOCOM (Vol. 6, pp. 1-11)

Evaluation on Rate Adaptation Algorithm Applied For Wireless Mesh Network

Penelitian ini mengevaluasi beberapa algoritma rate adaptation untuk mendapatkan algoritma yang paling sesuai digunakan pada jaringan wireless mesh network (WMN). Pada beberapa penelitian terdahulu, evaluasi terhadap algoritma-algoritma rate adaptation masih terbatas pada kinerja algoritma rate adaptation secara umum dan pada jaringan yang sederhana, sedangkan untuk penelitian ini dikhususkan pada kenaikan nilai throughput yang disebabkan oleh penerapan algoritma rate adaptation dan pada jaringan yang lebih kompleks yaitu WMN. Algoritma rate adaptation yang dipilih untuk dievaluasi adalah algoritma-algoritma yang sudah umum digunakan, yaitu algoritma auto rate fallback (ARF), adaptive auto rate fallback (AARF) dan collision aware rate adaptation (CARA). Evaluasi dilakukan melalui serangkaian simulasi menggunakan software NS-3 untuk mengetahui nilai throughput yang dihasilkan oleh masing-masing algoritma pada kondisi jaringan WMN dengan jumlah node yang berbeda-beda. Hasil evaluasi menunjukkan bahwa kinerja algoritma CARA mampu melampaui kinerja dua algoritma lainnya, yaitu ARF dan AARF untuk kondisi jaringan WMN yang kompleks (grid 4x5 dan 5x5). This paper attempts to evaluate some rate adaptation algorithms in order to find the most suitable algorithm to be used in the wireless mesh network (WMN) environment. In some previous researches, the evaluation on these algorithms is still limited on a general rate algorithm performance and in a simple network, while this research was devoted on the increase in throughput value due to the implementation of rate adaptation algorithm and in a more complicated network, WMN. The rate adaptation algorithms evaluated in this research were auto rate fallback (ARF), adaptive auto rate fallback (AARF) and collision aware rate adaptation (CARA), which are the most commonly used algorithm. The evaluation was carried out through a series of simulation using NS-3 software to find out the throughput value resulted by each algorithm. The evaluation result showed that the CARA algorithm outperformed two other algorithms, i.e. ARF and AARF, for a complex WMN condition (grid 4x5 and 5x5). Keywords: Jaringan WMN, throughput, rate adaptation algorithm, CARA, NS-3 Referensi Capone, A. & Carello, G. 2006. Scheduling optimization in wireless mesh networks with power control and rate adaptation. In  Sensor and Ad Hoc Communications and Networks, 2006. SECON'06. 2006 3rd Annual IEEE Communications Society on, (Vol. 1, pp. 138-147). IEEE.      Senthilkumar, D. & Krishnan, A. 2010. Throughput analysis of IEEE 802.11 multirate WLANs with collision aware rate adaptation algorithm. International Journal of Automation and Computing, 7(4), 571-577. Lacage, M., Manshaei, M. H., & Turletti, T. 2004, October. IEEE 802.11 rate adaptation: a practical approach. In Proceedings of the 7th ACM international symposium on Modeling, analysis and simulation of wireless and mobile systems (pp. 126-134). ACM. Kim, J., Kim, S., Choi, S., & Qiao, D. 2006, April. CARA: Collision-Aware Rate Adaptation for IEEE 802.11 WLANs. In INFOCOM (Vol. 6, pp. 1-11)

Chemical reaction optimization for task scheduling in grid computing

Grid computing solves high performance and high-throughput computing problems through sharing resources ranging from personal computers to supercomputers distributed around the world. One of the major problems is task scheduling, i.e., allocating tasks to resources. In addition to Makespan and Flowtime, we also take reliability of resources into account, and task scheduling is formulated as an optimization problem with three objectives. This is an NP-hard problem, and thus, metaheuristic approaches are employed to find the optimal solutions. In this paper, several versions of the Chemical Reaction Optimization (CRO) algorithm are proposed for the grid scheduling problem. CRO is a population-based metaheuristic inspired by the interactions between molecules in a chemical reaction. We compare these CRO methods with four other acknowledged metaheuristics on a wide range of instances. Simulation results show that the CRO methods generally perform better than existing methods and performance improvement is especially significant in large-scale applications. © 2011 IEEE.published_or_final_versio

A new computational approach for maximum link activation in wireless networks under the SINR model

Abstract-A fundamental and computationally challenging optimization task in wireless networks is to maximize the number of simultaneous transmissions, subject to signal-to-noise-andinterference ratio (SINR) requirements at the receivers. The conventional approach guaranteeing global optimality is to solve an integer programming model with explicit SINR constraints. These constraints are however numerically very difficult. We develop a new integer programming algorithm based on a much more effective representation of the SINR constraints. Computational experiments demonstrate that the new approach performs significantly better in proving optimality

Solution methods for planning problems in wireless mesh networks

Ankara : The Department of Industrial Engineering and the Graduate School of Engineering and Science of Bilkent University, 2012.Thesis (Master's) -- Bilkent University, 2012.Includes bibliographical references leaves 41-43.Wireless Mesh Networks (WMNs) consist of a finite number of radio nodes. A subset of these nodes, called gateways, has wired connection to the Internet and the non-gateway nodes transmit their traffic to a gateway node through the wireless media in a multi-hop fashion. Wireless communication signals that propagate simultaneously within the same frequency band may interfere with one another at a receiving node and may therefore prevent successful transmission of data. In order to circumvent this problem, nodes on the network can be configured to receive and send signals in different time slots and through different frequency bands. Therefore, a transmission slot can be defined as a pair of a certain frequency band and a specific time slot. In addition, by adjusting the power level of a radio node, its transmission range can be modified. Given a wireless mesh network with fixed node locations, demand rate at each node, and maximum power level for each node, we study the problem of carrying the traffic of each node to the Internet through the network. Our goal is to allocate capacities in proportion to the demand of each node in such a way that the minimum ratio is maximized. We propose a mixed integer linear programming (MILP) formulation to select a given number of gateway locations among the nodes in the network, to determine the routing of the traffic of each node through the gateway nodes, to assign transmission slots to each node in order to ensure no interference among wireless signals, and to determine the transmission power levels. In our study, we adopt the physical interference model, instead of the protocol interference, since this is more realistic. Since MILP formulation becomes computationally inefficient for larger instances; we developed several different approaches. Then, we proposed a combinatorial optimization model which successfully solves most of the instances. We tested our models and methods in several data sets, and results are presented.Özdemir, GörkemM.S

Routing and Scheduling Using Column Generation in IEEE 802.16j Wireless Relay Networks

Worldwide Interoperability for Microwave Access (WiMAX) has become an important standard in wireless telecommunication networks in recent years due to the increasing bandwidth requirements, as well as to customer demand for having ubiquitous access to the network. One of the most recent versions of WiMAX is IEEE 802.16-2009, but in this thesis we work with its 802.16j amendment. This amendment includes the use of relay stations (RS) to improve the network's throughput, with the RSs becoming intermediaries between the base station (BS) and the subscriber stations (SS). In the literature, there have been several authors claiming to perform joint routing and scheduling in wireless networks using the column generation technique. Nevertheless, these papers are not performing scheduling since they do not specify how time slots are allocated to each transmitting node over time (they only count the time slots it takes to transmit data). That is why we developed an optimization model (that is solved using column generation) having in mind the fact of performing real scheduling, not only counting time slots but taking into account the allocation of resources over a period of time. The model we developed chooses among a set of possible configurations (a set of transmitting links over a predetermined period of time slots) to calculate the time it takes to transmit data from end to end. After obtaining some simulation results with our model, we compared them with those of a model that does not perform real scheduling. The results show only minor differences in the total number of time slots that a transmission lasts since we can only assign a small number of time slots per configuration

Optimal Schedules for Data Gathering in Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are widely used for target monitoring: sensors monitor a set of targets, and forward the collected or aggregated data using multi-hop routing to the same location, called the sink. The resulting communication scheme is called ConvergeCast or Aggregated ConvergeCast. Several researchers studied the ConvergeCast and the Aggregated ConvergeCast, as to produce the shortest possible schedule that conveys all the packets or a packet aggregation to the sink. Nearly all proposed methods proceed in two steps, first the routing, and then the scheduling of the packets along the routes defined in the first step. The thesis is organized around four contributions. The first one is an improvement of the previous mathematical models that outputs (minimum-sized) multi-set of transmission configurations (TCs), in which a transmission configuration is defined as a set of links that can transmit concurrently. Our model allows the transmission of several packets per target, in both single-path and multi-path settings; we give two new heuristics for generating new improved transmission configurations. While such models go beyond the routing step, they do not specify an ordering over time of the configurations. Consequently, the second contribution consists of several algorithms, one exact and several heuristics, for ordering the configurations. Our results show that the approach of scheduling when restricted to a tree generated by the first contribution significantly outperforms the ordering of configurations of TC-approach for single-rate, single packet per sensor traffic patterns, but the TC approach gives better results for multi-rate traffic and when there are a large number of packets per sensor. In the last two contributions, we propose an exact mathematical model that takes care, in a single phase, of the routing and the scheduling, for the ConvergeCast and the aggregated ConvergeCast problem. They both correspond to decomposition models in which not only we generate transmission configurations, but an ordering of them. We performed extensive simulations on networks with up to 70 sensors for both ConvergeCast and Aggregated ConvergeCast, and compared our one phase results with one of the best heuristics in the literature

Optical Grid Network Dimensioning, Provisioning, and Job Scheduling

An optical grid network reliably provides high speed communications. It consists of grid resources (e.g., computing and data servers) and huge-data paths that are connected to geographically dispersed resources and users. One of the important issues is dimensioning optical grid networks, i.e., to determine the link bandwidth utilization and amount of server resources, and finding the location of servers. Another issue is the provisioning of the job requests (maximization of services) on the capacitated networks, also referred to as Grade of Service (GoS). Additionally, job scheduling on the servers has also an important impact on the utilization of computing and network resources. Dimensioning optical grid network is based on Anycast Routing and Wavelength Assignment (ACRWA) with the objective of minimizing (min-ACRWA) the resources. The objective of GoS is maximizing the number of job requests (max-ACRWA) under the limited resources. Given that users of such optical grid networks in general do not care about the exact physical locations of the server resources, a degree of freedom arises in choosing for each of their requests the most appropriate server location. We will exploit this anycast routing principle -- i.e., the source of the traffic is given, but the destination can be chosen rather freely. To provide resilience, traffic may be relocated to alternate destinations in case of network/server failures. This thesis investigates dimensioning optical grids networks and task scheduling. In the first part, we present the link capacity dimensioning through scalable exact Integer Linear Programming (ILP) optimization models (min-ACRWA) with survivability. These models take step by step transition from the classical RWA (fixed destination) to anycast routing principle including shared path protection scheme. In the second part, we present scalable optimization models for maximizing the IT services (max-ACRWA) subject to survivability mechanism under limited link transport capacities. We also propose the link capacity formulations based on the distance from the servers and the traffic data set. In the third part, we jointly investigate the link dimensioning and the location of servers in an optical grid, where the anycast routing principle is applied for resiliency under different levels of protection schemes. We propose three different decomposition schemes for joint optimization of link dimensioning and finding the location of servers. In the last part of this research, we propose the exact task scheduling ILP formulations for optical grids (data centers). These formulations can also be used in advance reservation systems to allocate the grid resources. The purpose of this study is to design efficient tools for planning and management of the optical grid networks

Scheduling optimization in Wireless MESH Networks with Power Control and rate Adaptation

Wireless MESH networks are a new networking paradigm that allow to extend the coverage of traditional wireless access networks with multi-hop connections through fixed wireless mesh routers. Wireless MESH networks partially replace wired backbone networks, and it is reasonable to carefully plan radio resource assignment in order to provide quality guarantees to traffic flows. Differently from ad hoc networks, energy consumption is usually not a problem with wireless MESH routers, routes are quite stable and bandwidth requirements of traffic flows can be considered almost constants. In this paper we study the scheduling optimization problem in wireless MESH networks assuming a time division multiple access (TDMA) scheme, a dynamic power control able to vary emitted power slot-by-slot, and a rate adaptation mechanism that sets transmission rates according to the signal-to-interference-and-noise ratio (SINR). Traffic quality requirements are expressed in terms of minimum bandwidth and modelled with constraints defining the number of information units (packets) that must be transmitted on each link per frame. We propose an alternative problem formulation where decision variables represent compatible sets of links active in the same slot. Approaches to solve both lower and upper bound for the problem are proposed: since compatible set variables are exponentially many, we use column generation to compute a lower bound for the problem. Heuristic approaches to compute feasible integer solutions are proposed and tested