Amir Esmailpour

Dynamic QoS-Based Bandwidth Allocation Framework for Broadband Wireless Networks

Broadband wireless communication systems, namely, Worldwide Interoperability for Microwave Access (WiMAX) and Long-Term Evolution (LTE), promise to revolutionize the mobile users wireless experience by offering many of the services and features promised by fourth-generation (4G) wireless systems, such as supporting multimedia services with high data rates and wide coverage area, as well as all-Internet Protocol (IP) with security and quality-of-service (QoS) support. These systems, however, require proficient radio resource management (RRM) schemes to provide the aforementioned features they promise. In this paper, we propose a new framework, which is called dynamic QoS-based bandwidth allocation (DQBA), to support heterogeneous traffic with different QoS requirements in WiMAX networks. The DQBA framework operates as such; it dynamically changes the bandwidth allocation (BA) for ongoing and new arrival connections based on traffic characteristics and service demand. The DQBA aims at maximizing the system capacity by efficiently utilizing its resources and by being fair, practical, and in compliance with the IEEE 802.16 standard specifications. To achieve its objectives, DQBA employs a flexible architecture that combines the following related components: 1) a two-level packet scheduler scheme; 2) an efficient call admission control policy; and 3) a dynamic BA mechanism. Simulation results and comparisons with existing schemes show the effectiveness and strengths of the DQBA framework in delivering promising QoS and being fair to all classes of services in a WiMAX network.

Packet scheduling scheme with quality of service support for mobile WiMAX networks

Radio Resource Management (RRM) techniques used in Worldwide Interoperability for Microwave Access (WiMAX) can provide for many of the services and features promised by 4G wireless networks, such as supporting multimedia services with high data rates, and wide coverage area, as well as all-IP with Quality of Service (QoS) support and security. In this paper we propose a new scheduling scheme and admission control policy for WiMAX that efficiently enhances performance and utilizes resources, while being fair, practical and in compliance with the IEEE 802.16 specifications. Our scheduler is dynamic and based on hierarchical and ad-hoc models. Our solution provides QoS support to all traffic classes defined by the standard, and it dynamically changes the bandwidth allocation depending on the traffic characteristics and service demands. Simulation results show that the proposed solution can deliver QoS support and be fair to all classes of service in a WiMAX network.

Machine Learning with Big Data An Efficient Electricity Generation Forecasting System

Abstract Machine Learning (ML) is a powerful tool that can be used to make predictions on the future nature of data based on the past history. ML algorithms operate by building a model from input examples to make data-driven predictions or decisions for the future. The growing concept “Big Data” has brought much success in the field of data science; it provides data scalability in a variety of ways that empower data science. ML can also be used in conjunction with Big Data to build effective predictive systems or to solve complex data analytic problems. In this work, we propose an electricity generation forecasting system that could predict the amount of power required at a rate close to the electricity consumption for the United States. The proposed scheme uses Big Data analytics to process the data collected on power management in the past 20 years. Then, it applies a ML model to train the system for the prediction stage. The model can forecast future power generation based on the collected data, and our test results show that the proposed system can predict the required power generation close to 99% of the actual usage. Our results indicate that the ML with Big Data can be integrated in forecasting techniques to improve the efficiency and solve complex data analytic problems existing in the power management systems.

Efficient routing for wireless mesh networks using a backup path

SUMMARY Wireless mesh networks (WMNs) have a proven record in providing viable solutions for some of the fundamental issues in wireless networks such as capacity and range limitations. WMN infrastructure includes clusters of mobile ad-hoc networks connected through a fixed backbone of mesh routers. The mesh network can be constrained severely because of various reasons, which could result in performance degradation such as a drop in throughput or long delays. Solutions to this problem often focus on multipath or multichannel extensions to the existing ad-hoc routing protocols. In this paper, we propose a novel solution by introducing an alternative path to the mesh backbone that traverses the mobile ad-hoc networks part of the WMN. The new routing solution allows the mobile nodes (MNs) to establish direct communication among peers without going through the backbone. The proposed alternative ad-hoc path is used only when the mesh backbone is severely constrained. We also propose, for the first time in WMNs, using MNs with two interfaces, one used in the mesh backbone communication and the other engaged in the ad-hoc network. A scheme is presented for making the MN aware of link quality measures by providing throughput values to the ad-hoc on-demand distance vector protocol. We use piggybacking on route reply messages in ad-hoc on-demand distance vector to avoid incurring additional costs. We implemented our solution in an OPNET simulator and evaluated its performance under a variety of conditions. Simulation results show that the alternative ad-hoc path provides higher throughput and lower delays. Delay analysis show that the throughput improvement does not impose additional costs. Copyright

Interoperability between WiMAX and WiFi in a testbed environment

This paper shows a full end-to-end WiFi-WiMAX network deployment in a testbed environment. It also demonstrates network integration of various wireless technologies that can be used by ISPs to provide services to large and small enterprise customers. The research indicates that WiFi-WiMAX deployment does not deteriorate throughput as compared to a standalone WiMAX system. The complete network architecture is comprised of an ISP core and several sites connecting to the core using a combination of WiMAX and WiFi and based deployments. The throughput of approximately 967.5 kbps was observed throughout the path and shows a steady performance across various parts of the network regardless of the technology involved.

A Hybrid Data Center Architecture for Big Data

In the past few years, Big Data analytics have changed the way computing services and resources are being used. New users are getting into the cloud services provided by data centers on a daily basis, and the number of applications hosted on the clouds is rapidly increasing. However, existing data center architectures cannot cope with the black-box nature of the cloud nor with Big Data analytics. Current data center networks using electrical packet switches have many disadvantages. Electrical links consume too much power to handle the increased bandwidth demanded by emerging applications. They are often not suitable for providing high bandwidth at low latency and have bottleneck issues. A promising solution involves adding optical interconnections to the infrastructure in data centers offering high throughput, low latency, and incredibly low energy consumption compared to the current data center networks based on commodity switches. In this work, we propose a hybrid electrical and optical networking architecture for data centers hosting Cloud Computing and Big Data applications. Furthermore, we analyze and compare application behaviors with current and proposed hybrid architectures. The results show that hybrid architecture provides a viable solution to data center issues and easily outperforms existing data center architectures. The results reflect that hybrid architecture reduces the delay by nearly 39% and decreases the cost of cooling systems from 49.57% to 27% of the total costs, while reducing the overall long-term costs of data centers.

A Novel Scheme for Packet Scheduling and Bandwidth Allocation in WiMAX Networks

Radio Resource Management (RRM) techniques used in the Worldwide Interoperability for Microwave Access (WiMAX) can provide for many of the services and features promised by 4G wireless networks, such as supporting multimedia services with high data rates, and wide coverage area, as well as all-IP with security and Quality of Service (QoS) support. The IEEE 802.16 standard, associated with the WiMAX, leaves the details of RRM components open for the vendors to explore. In this paper we propose a novel scheme for the QoS support in WiMAX including packet scheduling and bandwidth allocation strategies. The proposed solution efficiently enhances performance and utilizes resources, while being fair, practical and in compliance with the IEEE 802.16 standard specifications. Our solution provides QoS support to all traffic classes defined by the standard, and it dynamically changes the bandwidth allocation based on the traffic characteristics and service demands. Simulation results show that the proposed solution can deliver QoS support and be fair to all classes of service in a WiMAX network.

Topological-based architectures for wireless mesh networks

The wireless mesh network and the associated IEEE 802.11s standard have attracted an enormous amount of research in the wireless research community in the past few years. Nevertheless, WMN architecture has not received much needed attention compared to other topics in this area of research. Based on topological differences, various network architectures are possible for WMNs, and we believe such architectures could affect wireless characteristics differently. In this article we provide an overview of architectural design approaches for WMNs, then summarize the state-of-the-art research findings and suggest further topics that need to be addressed. Additionally, we identify three different types of architectures for WMNs: campus mesh, downtown mesh, and long-haul mesh. Furthermore, we discuss and investigate different WMN characteristics that could be affected by commonly deployed architectures. Among the considered characteristics we select routing, network management, and network performance for further analysis, and look at the challenges these architectures face with respect to those characteristics. To illustrate these challenges, we perform a simple experiment to show that LHM and DTM under identical network environments show significant differences in performance parameters such as throughput and delay.

Ad-hoc Path: an Alternative to Backbone For Wireless Mesh Networks

The access link contention can severely constrain the end- to-end throughput of the path between a source and destination mobile node connected through the backbone of the wireless mesh network (WMN). In this paper, we propose an integrated routing system for WMN that includes both the backbone paths and the ad-hoc paths formed as a result of direct communication among mobile nodes without going through the backbone. In our proposed routing system, an alternative ad-hoc path can be used only when the primary backbone path is severely constrained due to access links contention. We propose a scheme that allows the source mobile node to evaluate the throughput of the backbone and ad-hoc paths, and select one path for communicating with the destination. We implemented the proposed routing system in OPNET simulator, and evaluated the performance of our scheme under variety of conditions. Simulation results show that the alternative ad-hoc path is effective in delivering higher throughput when backbone path is severely constrained.

Integrated Routing System for Wireless Mesh Networks

Recently wireless mesh network (WMN) has become popular especially for its low cost deployment in the areas of poor network infrastructure and terrain of difficult deployment. Although paths in WMN backbone network are stable, the access link contention can severely constrain the end-to-end throughput. We proposed an integrated routing system for WMN that exploits both paths through the backbone network and through the ad-hoc access network of mobile nodes. The ad-hoc path is considered as an alternative path and is used only when the primary backbone path is severely constrained due to access links contention. We have shown through simulation that alternative path is effective in delivering high throughput in that situation. We also proposed a scheme for initiating the route discovery of the ad-hoc path. We investigated the use of OSPF in the backbone network and proposed solutions of dealing with multi-area OSPF configuration in the backbone and auto-configuration of OSPF wireless links