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In this paper, we propose a method to estimate user’s movement path using Wi-Fi authentication log. Large organization often have many Wi-Fi access points (APs) which are centrally managed by a wireless LAN controller, usually with roaming feature. While the user moves around the area covered by the Wi-Fi network, the AP they connect to will change. Each time the connected AP change, an authentication such as 802.1x is performed. The credentials such as user ID and password are sent to an authentication server via the controller. This allows the controller to know who has connected to which access point and when. Our method is to track a certain person’s movement path from the authentication log afterword. Assuming the authentication log is recorded where the roaming occurred, the area where the device was at point could be estimated. By combining with the structure of the building, we are able to roughly estimate the user’s movement path.

In this chapter, we investigate the channel assignment problem (CAP) that is critical in wireless communication applications. Researchers strive to develop algorithms that are able to effectively assign limited channels to a number of cells with nonhomogeneous demands. Inspired by the recent success of metaheuristics, a hybrid ant colony optimisation (HACO) is proposed in this chapter. The HACO embodies several problem-dependent heuristics including ordering, sequential packing, and a local optimiser into an ACO framework. The advantages of this hybrid are two-fold. First, the EMC constraints can be effectively handled by the problem-dependent heuristics instead of using a penalty function as observed in other works which may lengthen the elapsed time in order to reach convergence. Second, the embedded heuristics serve as intensification strategies conducted by the metaheuristic framework and help improve the generated solutions from different view points. The performance of the HACO algorithm is evaluated on the Philadelphia benchmark set, such that it can be compared to that of existing approaches. It is observed from the experimental results that the HACO algorithm can solve optimally six of the eight benchmark problems and obtain near-optimal solutions for the other two problems which have been known to be the most difficult in the literature. For practical reasons, we only allow the HACO algorithm to run for a relatively short time compared to that used by other approaches. It is plausible to get a better result if more computational time is allocated.

In wireless networks, seamless roaming allows a mobile user (MU) to utilize its services through a foreign server (FS) when outside his home server (HS). However, security and efficiency of the aut...

Wireless LAN controller (WLC) is used to manage and control Access points (APs) in Wireless local area network (WLAN). Proxy mobile IPv6 (PMIPv6) protocol supports network-layer mobility in WLC based WLAN. However, it introduces extra delay in delivering packets from the APs to the WLC. We use Mobile access gateway (MAG) chain to reduce packet delay. The handoff delay and packet delivery delay under the proposed scheme are derived, based on which we formulate the delay minimization problem whose solution leads to the optimal MAG chain length. Numerical analysis results indicate that the proposed scheme outperforms the existing scheme in terms of delay in the case when the delay between Local mobility anchor (LMA) andWLC is relatively greater than the delay between two neighboring WLCs. The proposed scheme is able to reduce packet loss resulting from the traditional handoff procedure introduced in the PMIPv6 protocol and that due to delay limitation.

Sensor network protocol stacks require the addition or adjustment of functions based on customer requirements. Sensor network protocols that require low delay and low packet error rate (PER), such as wireless control networks, often adopt time division multiple access (TDMA). However, it is difficult to add or adjust functions in protocol stacks that use TDMA methods. Therefore, to add or adjust functions easily, we propose NES-SOURCE, a compact wireless control network protocol with a fast path-switching function. NES-SOURCE is implemented using carrier sense multiple access/collision avoidance (CSMA/CA) rather than TDMA. Wireless control networks that use TDMA prevent communication failure by duplicating the communication path. If CSMA/CA networks use duplicate paths, collisions occur frequently, and communication will fail. NES-SOURCE switches paths quickly when communication fails, which reduces the effect of communication failures. Since NES-SOURCE is implemented using CSMA/CA rather than TDMA, the implementation scale is less than one-half that of existing network stacks. Furthermore, since NES-SOURCE’s code complexity is low, functions can be added or adjusted easily and quickly. Communication failures occur owing to changes in the communication environment and collisions. Experimental results demonstrate that the proposed NES-SOURCE’s path-switching function reduces the amount of communication failures when the communication environment changes owing to human movement and others. Furthermore, we clarify the relationships among the probability of a changing communication environment, the collision occurrence rate, and the PER of NES-SOURCE.

At present, the need for internet access in public area using wireless connections is increasing drastically and this should be supported by good network infrastructure. Wireless network is one of the best alternative in building a practical internet network. WDS is a system to develop wireless internet network without having to use cable as its backbone for access point but instead utilize wireless path from its access point. The problems that often arise in the design of wireless LAN network is the poor signal received by the user due to the installation of an access point that is poor location-wise. This is because at some point it is very difficult to install Access point using cable because the distance is too far from the existing router. In this paper, we propose to use three scenario of WDS mode to compare its performance. We investigate three different topology policy models of the WDS Bridge point-to-point, WDS Bridge point to multipoint and WDS repeater. The use of these three topologies aims to reach locations that are not covered by wireless LAN network, in addition this method can save the use of network resources such as LAN cables. Based on the simulation results, it is found that the topology point to point gives better value but it generated higher delays. The delay generated on point to point is higher than other topologies. Meanwhile, the measurement results are not much different on topology point to multipoint with repeater topology. The point to multipoint topology is slightly better than the repeater of the three QoS parameters.

The multi-packet reception (MPR) technique enables access points to correctly receive simultaneously transmitted packets. Therefore, the network saturation throughput can be significantly improved by introducing MPR into wireless local area networks (WLANs). In this letter, we develop a novel analytical model to evaluate the saturation throughput of a WLAN with MPR. In contrast to previous models, we adopt the stationary distribution of backoff counter value after a generic overlapping transmission process to characterize the behavior of a contending station. Then, we derive the saturation throughput based on this distribution. Comparisons with simulation results show that our analytical model provides a close evaluation of the saturation throughput. Moreover, the impacts of several parameters on the saturation throughput are also investigated using the proposed model.

Although full-duplex transmission can be helpful for enhancing wireless link capacity, it may require extra energy to overcome the residual self-interference. In this paper, we investigate the tradeoff between energy consumption and delay in a multichannel full-duplex wireless LAN. The goal is to minimize the energy consumption while keeping the traffic queues stable. With Lyapunov optimization, we develop a throughput optimal online scheme to achieve the goals with optimized channel assignment, transmission scheduling, and transmission mode selection. We study the influence of full-duplex transmissions on the network capacity region, prove the optimality of the proposed algorithm, and derive upper bounds for the average queue length and energy consumption, which demonstrate the energy-delay tradeoff in such systems. The proposed algorithm and the capacity region analysis are validated with simulations.

In this paper, a novel Medium Access Control (MAC) protocol for industrial Wireless Local Area Networks (WLANs) is proposed and studied. The main challenge in industry automation systems is the ultra-low network latency with a target upper bound in the order of 1 ms while maintaining high network reliability and availability. The novelty of the proposed wireless MAC protocol resides in its similar latency performance as its counterpart in wired industrial LAN. First, the functional design of the MAC protocol is introduced. Then its performance results gained from hardware implementation (SystemC and VHDL) on an FPGA platform are presented. Finally, a real-time communication module which achieves the ultra-low latency required in industrial automation is described.

A load balancing mechanism can adjust the load distribution among access points (APs) and improve resource utilization for dense wireless local area networks (WLANs). In this paper, we propose a semi-matching-based load balancing scheme for the IEEE 802.11 dense WLANs. The proposed scheme runs in a centralized controller. The controller judges whether the load is unevenly distributed according to the collected channel busy time ratio information of the entire network, and triggers the load balancing mechanism accordingly. In order to realize load balancing among APs and maximize the overall network throughput, we model the station to AP association problem as a weighted bipartite graph matching problem and find the optimal semi-matching using the Kuhn-Munkres (K-M) algorithm. Simulation results show that the proposed scheme achieves performance improvement comparing with traditional schemes.

Serving a Dynamic Host Configuration Protocol (DHCP) request with some additional services package may cause a conventional wireless router consumes more memory resources. High memory usage would break the DHCP request process if the wireless router becomes busy. In this paper, the centralized DHCP servers is proposed to overcome this situation. In term of Cisco product there is Wireless LAN Controller that can solve that situation. In this research, we suggest an open source solution for this situation. The original master and backup algorithm are modified to reserve DHCP request. DHCP master server serves many connected network under the main router. The modification of original master and backup algorithm is located in resource allocation calculation in the main router. Computer agent checks the memory of the main router to decide a diversion of DHCP pool to the backup router. Run test results show that the proposed method has an acceptable lease time. It can handle 254 DHCP requests within only 0.6 seconds longer than the conventional method. Further, the number of client that could be reserved by the proposed method is better than the method used in OpenWRT router, which is about 100 more clients successfully receive their IP.

A simple wavelength-division-multiplexing passive optical network is proposed in this paper. By simply designing the remote node, the virtual-ring local area network (LAN) services transmitted among optical network units are realized. And coupled with conventional broadband light source and spectrum-sliced technology, the network can support the LAN services in a cost-effective way. More particularly, the whole wavelength band of downstream services can also be reused for LAN services by selecting a special port of Arrayed Waveguide Grating. The simulation results indicate the 10 Gb/s LAN communication in this network can be achieved with the help of forward error correction.

Wireless networks are today employed as complementary access technology, implemented on the last hop towards the Internet end-user. The shared media that wireless deployments provide and which is relevant to interconnect multiple users has a limited technical design, as only one device can be served per unit of time, design aspect that limits the potential applicability of wireless in dense environments. This paper proposes and evaluates a novel MAC-layer mechanism that extends current wireless networks with the possibility to perform downstream transmission to multiple devices within a single transmission time-frame, resulting in improved fairness for all devices. The mechanism, which is software-defined, is backward-compatible with current wireless standards and does not require any hardware changes. The solution has been validated in a realistic testbed, and the paper provides details concerning the computational aspects of our solution; a description of the implementation; and results extracted under different realistic scenarios in terms of throughput, packet loss, as well as jitter.

In uplink wireless local area networks (WLANs) with multi-packet reception (MPR) which can be implementable with multi-user multiple-input multiple-output techniques, partial successes among simultaneous transmissions may frequently occur due to frame errors. This causes an increase in the contention window size only for the failed stations (STAs) under the binary exponential backoff algorithm, and a severe unfairness problem in terms of channel access opportunity may occur among the STAs with different frame error rates. In this letter, we propose a novel medium access control (MAC) protocol to support fair channel access in uplink WLANs with MPR. Analysis and simulation results show that our proposed MAC protocol can significantly improve the fairness in terms of both channel access opportunity and throughput.

As a promising solution for handling super dense wireless networks, wireless local area networks (WLANs) have been intensively considered due to their wide availability. However, the contention-based MAC protocol in WLANs should be modified because of its inefficiency. To this end, we consider a recently proposed novel MAC protocol called the renewal access protocol (RAP). With the RAP, we analyze two strategies for resolving collisions efficiently and achieving optimal throughput performance in super dense WLANs: strategies without and with grouping. First, we analyze the asymptotic behavior of the RAP itself (i.e., without grouping) as the number of terminals goes to infinity. We show that the RAP can achieve optimal throughput even in super dense WLANs and the relevant optimal access probability can be derived in a closed form. Second, we propose a grouping strategy in the RAP called the grouped RAP (G-RAP). While a grouping strategy in the IEEE 802.11ah standard is based on time division, our G-RAP is based on transmission attempts. So the G-RAP does not waste channel resources. We show that the G-RAP achieves the optimal network throughput for any group structure if terminals use the optimal access probability that we derive. Our analytical results are validated by simulation.

Network virtualization is an emerging technology for solving the rigidity of the physical network infrastructure. The innovative technique virtualizes all resources in the network, including the network links and nodes, and provides a number of virtual networks on a single network infrastructure. In order to realize a virtual network, a thorough and complete monitoring of all resources in the network should be performed firstly. OpenFlow is an open source stack for network virtualization. However, it is impossible to apply OpenFlow to AP-based legacy wireless LAN environment because OpenFlow targets ethernet-based LAN environment. In this paper, we implement an adaptor-styled virtual switch for AP-based wireless LAN through customizing the Open vSwitch which is a virtual switch of OpenFlow. The evaluation test results show that the implemented OpenFlow stack operates successfully. The implemented OpenFlow stack can now be plugged immediately in existing AP-based wireless LAN environment and plays network resource monitoring. In the future, we can develop wireless LAN virtualization applications on the wireless OpenFlow stack.

Wireless sensor networks consisting of several sensors deployed in a given area, under an internet of things (IoT) paradigm, are considered. Sensor nodes may or may not be close enough to communicate with each other in order to perform collaborative transmissions. A communication protocol based on random access and orthogonal frequency division multiple access (OFDMA) is proposed in order to allow the sensors to operate autonomously by transmitting their measured data to a central processing system, where it is processed and analyzed. Whenever it has data to transmit, each sensor independently accesses a time-frequency slot in a probabilistic manner to avoid collisions. A controlling entity, e.g., a central base station (BS) covering a certain sensor deployment area receives the sensor transmissions and provides synchronization information by periodically transmitting a pilot signal over the available OFDMA subcarriers. Sensors use this signal for channel quality estimation. Results show that this approach performs well in terms of transmission data rates and collision probability.

Wireless technologies are the critical components that facilitate ubiquitous communications among users, devices, and humans-machines. IEEE 802.11 is a popular wireless access technology which uses a truncated binary exponential backoff algorithm in a shared channel. But its performance deteriorates rapidly if there are numerous simultaneous active connections. Multi-channel wireless network, consisting of control and data channels, is one possible solution to offer sustainable high performance large-scale networks. In this letter, we analyze the performance of a multi-channel backoff (MCB) algorithm, which gives a non-zero performance bound for large network sizes. Through simulations and analysis, settings of associated system parameters are determined to offer high goodput performance.

It is predicted that billions of intelligent devices and networks, such as wireless sensor networks (WSNs), will not be isolated but connected and integrated with computer networks in future Internet of Things (IoT). In order to well maintain those sensor devices, it is often necessary to evolve devices to function correctly by allowing device management (DM) entities to remotely monitor and control devices without consuming significant resources. In this paper, we propose a lightweight RESTful Web service (WS) approach to enable device management of wireless sensor devices. Specifically, motivated by the recent development of IPv6-based open standards for accessing wireless resource-constrained networks, we consider to implement IPv6 over low-power wireless personal area network (6LoWPAN)/routing protocol for low power and lossy network (RPL)/constrained application protocol (CoAP) protocols on sensor devices and propose a CoAP-based DM solution to allow easy access and management of IPv6 sensor devices. By developing a prototype cloud system, we successfully demonstrate the proposed solution in efficient and effective management of wireless sensor devices.

This letter considers an energy consumption minimization problem of duty-cycled wireless sensors which are associated with a central controller, say an access point (AP), in a single-hoped synchronous wireless sensor network (WSN). The cost function we propose consists of the energy consumed during periodic wake-ups for wireless sensors to check a beacon frame from the AP and the one consumed for them to receive packets waiting in the AP's queue. This letter provides an optimal sleep interval as a closed form solution of minimizing energy consumption, which is expressed as mean packet inter-arrival times, mean packet transmission times over erroneous wireless channel, and power consumption at each wake-up and a packet transmission.

As full-duplex wireless communication evolves into a practical technique, it will be built into communication nodes in many application scenarios. However, it is difficult to do so for legacy communication nodes. Thus, full-duplex communication nodes will coexist with half-duplex communication nodes in the same application environment. In this paper, a wireless local area network with a full-duplex access point (AP) and half-duplex clients is studied, and a media access control (MAC) protocol called asymmetrical duplex (A-Duplex) is developed to support efficient coexistence between half-duplex clients and the full-duplex AP. A-Duplex explores packet-alignment-based capture effect to establish dual links between the AP and two different clients. In this way, the capability of a full-duplex AP can be utilized by half-duplex clients, which leads to much improved network throughput. Moreover, to ensure fairness of the MAC protocol, a virtual deficit round-robin algorithm is proposed for the AP to select appropriate half-duplex clients for dual-link setup. A-Duplex does not require any change in the physical layer of half-duplex clients; only an update of MAC driver is necessary. Thus, it is well suited for coexistence between half-duplex clients and a full-duplex AP. Both analysis and simulations are conducted to evaluate performance of A-Duplex. Results show that it improves the throughput by 48% and 188% and reduces the average packet delay by 26% and 22%, as compared to the IEEE 802.11 Distributed Coordination Function with and without RTS/CTS, respectively. Moreover, the throughput remains steady as the number of clients grows. A-Duplex also maintains a high level of fairness.

Wireless communication networks are pervading every aspect of our lives due to their fast, easy, and inexpensive deployment. They are becoming ubiquitous and have been widely used to transfer critical information, such as banking accounts, credit cards, e-mails, and social network credentials. The more pervasive the wireless technology is going to be, the more important its security issue will be. Whereas the current security protocols for wireless networks have addressed the privacy and confidentiality issues, there are unaddressed vulnerabilities threatening their availability and integrity (e.g., denial of service, session hijacking, and MAC address spoofing attacks). In this paper, we describe an anomaly based intrusion detection system for the IEEE 802.11 wireless networks based on behavioral analysis to detect deviations from normal behaviors that are triggered by wireless network attacks. Our anomaly behavior analysis of the 802.11 protocols is based on monitoring the n-consecutive transitions of the protocol state machine. We apply sequential machine learning techniques to model the n-transition patterns in the protocol and characterize the probabilities of these transitions being normal. We have implemented several experiments to evaluate our system performance. By cross validating the system over two different wireless channels, we have achieved a low false alarm rate (

Recent advances in signal processing have demonstrated in-band full-duplex capability at WiFi ranges. In addition to simultaneous two-way exchange between two nodes, full-duplex access points can potentially support simultaneous uplink and downlink flows. However, the atomic three-node topology, which allows simultaneous uplink and downlink, leads to inter-client interference. In this paper, we propose a random-access medium access control protocol using distributed power control to manage inter-client interference in wireless networks with full-duplex-capable access points that serve half-duplex clients. Our key contributions are two-fold. First, we identify the regimes in which power control provides sum throughput gains for the three-node atomic topology, with one uplink flow and one downlink flow. Second, we develop and benchmark PoCMAC, a full 802.11-based protocol that allows distributed selection of a three-node topology. The proposed MAC protocol is shown to achieve higher capacity as compared to an equivalent half-duplex counterpart, while maintaining similar fairness characteristics in single contention domain networks. We carried out extensive simulations and software-defined radio-based experiments to evaluate the performance of the proposed MAC protocol, which is shown to achieve a significant improvement over its half-duplex counterpart in terms of throughput performance.

In industrial applications of wireless sensor networks (WSNs), synchronized sampling of data on each sensor node is often required. Thus, the wireless communication protocol needs to support accurate timing synchronization. If due to a high sampling rate also high data throughput is required, WSNs based on the IEEE 802.15.4 physical layer often do not provide sufficient data rate. Wireless communications based on the well-established IEEE 802.11 wireless local area network (WLAN) standard provides high data throughput but not an accurate timing synchronization unless the protocol stack is severely changed. We propose two low-complexity consensus-based synchronization algorithms for the hybrid WSN introduced, which are executable at limited embedded computing capacity, e.g., on an 8-b microcontroller. A time division multiple access-based synchronization packet broadcasting with three-step-controlled or proportional-integral (PI)-controlled clock adjustment enables 1-kHz sensor sampling rate with a sampling jitter $\mu $ s for the three-step-controlled synchronization algorithm and $ for the PI-controlled algorithm.

wireless network is a type of network where various physical devices (e.g. computer, laptops, PDAs etc) are interconnected with each other using network infrastructure. Owing to wireless medium of data communication, the security risk is potentially high for unauthorized access and intrusion of various malicious programs. The security protocols of wireless network are governed by family of IEEE 802.11 standards. Wireless Network is studied in research with respect to wireless LAN (Local Area Network), wireless mesh network, wireless sensor network, mobile adhoc network, etc. In recent times, wireless sensor network was on constant focus among the research community owing to its potential advantage of data collection in remote areas as well as security problems associated with it. Wireless Sensor Network (WSN) consists of various sensor motes that form a cluster and perform data aggregation. Usually, the aggregated data is forwarded from the sensor nodes to the base station, which then reaches to user for analysis. The security problems is a matter of concern even for wireless sensor network that aims for either compromising the routing protocols or invoke illegitimate access to resources by bypassing the security protocols. In a wireless sensor network, the commununication takes place by group based, where sensor nodes are deployed in groups and each group performs communication using keys. Therefore this paper reviews some of the potential key-management techniques in past for maintaining group based communication and extracts the research gap.

A set of measurement system for the testing of transmission lines, composing of wireless center station, wireless current acquisition and transmission nodes, wireless voltage acquisition and transmission node, was designed, which was based on wireless communication. The high speed wireless bridge working at 2.4GHz together with the clock synchronization module based on the IEEE1588 communicating protocol were both employed for the communication and time synchronization separately. The measurement system has data storage, waveform display, data analysis, automatic report generation and other functions. The measurement system can greatly reduced arrangement of cables, thereafter improved the test efficiency.

Wireless Wireless network finds application in military environments, emergency, rescue operations and medical monitoring due to its self-configuring nature. As the availability of resources such as processing power, buffer capacity and energy are limited in wireless networks; it is required to devise efficient algorithms for packet forwarding. Due to the dynamic nature of the wireless environment, the traditional packet forwarding strategies cannot guarantee good network performance every time. This paper proposes a method for learning data flow rates in wireless network to improve quality of service in the network. Each node in the network learns the environment using reinforcement learning approach and selects appropriate neighbours for packet forwarding. In order to improve the learning capacity of nodes, the hierarchical docition technique is employed. Docition applied to each layer of network, which selects a set of special nodes which has more information about the environment and share this information with less informative nodes. The algorithm is tested in a geographical routing protocol and the results indicate improved network performance.

The design of a wireless water level control system is introduced and discussed in detail. In this system, the wireless Proportional Integral (PI) controller is developed using the LabVIEW graphical user programming language. Zigbee wireless technology is chosen for the wireless data transfer system. The experimental testbed was built and the system software and hardware were implemented. In order to compare the performance of the wired and wireless system, a corresponding wired water level control system was built. Experimental results show that under the same PI parameters, the settling time of the wired system is 3.3 times faster than the wireless system. However, the percent overshoot using the wireless controller is 4% smaller.

Several service applications have been reported by many who proposed the use of wireless LANs (WLANs) over a wide variety of outdoor deployments. In particular, the upcoming IEEE 802.11ah WLAN protocol will enable a longer transmission range between WLAN access points (APs) and stations (STAs) up to multiple kilometers using carrier frequencies at 900 MHz. However, limitations of WLAN outdoor installations have been found of the plethora of WLAN protocols in experimental studies. This article summarizes the challenges and provides a comprehensive overview of suggested improvements. As the standardization of the IEEE 802.11ah is reaching its final stage, important protocol aspects as well as new features are to be outlined. Interference problems and issues with the WLAN configuration, the physical layer (PHY), and media access control (MAC) are of paramount importance in outdoor WLAN networks, and thus, are discussed in detail. Further, we examine the reported upper boundaries in throughput and link reliability of long-range WLANs in different environments, including sea-surfaces, unmanned aerial vehicles (UAVs), and tunnels. At the end of this study, we reflect on the major issues regarding sub-1 GHz (S1G) WLANs and propose avenues for further research.

Virtual access point (VAP) is one of the most useful wireless virtualisation technologies because of its concurrent operation to compose multiple wireless networks via generating service set identifier. A single physical wireless NIC could access multiple networks in a single channel and thus establish a variety of wireless access point without additional wireless network interface. However, as the number of VAP increases, available bandwidth is reduced due to the fact that the number of management frame is increased dramatically in a single channel. Since the management frames should be sent as a basic data rate, channel utilisation and overall network performance would be degraded. To address this problem, system virtualisation is employed to augment wireless NIC hardware. Augmented wireless NICs are exposed to the guest OS and thus can access different wireless channel physically. The results obtained mitigate the bandwidth utilisation of management frame composed to the legacy VAP scheme, increasing round-trip time latency slightly.

This exploratory study analyzed the current complications in the Manufacturing organizations for transferring files between two or more sites in-between an organization over an unsecured network communication. Based on the analysis we provide reliable implementation by an appropriate solution to improve and develop the performance of the network communication to help the company to progress the quality of work. The initial phase of the study analyses about Virtual Private Network (VPN) based on the network layers and identifies the underneath difficulties in VPN while data travels over the network in the form of encapsulation and the traffic of the fundamental network. Because of such an encapsulation technique used in VPN, it increases the network traffic which affects the bandwidth of a low-speed internetworking communication. By analyzing various case studies, it was identified Multiprotocol Label Switching (MPLS) technology gives a feasible solution to put the network communication on the right track. It creates secure and reliable connectivity between organization sites and was effectively implemented in the place where slow speed network for connectivity between organizations are found. The recommending this MPLS solution, it helps organizations to share and effectively utilize the servers and service between organizations for secure, reliable and effective communication. Also by considering network security factor as a very significant factor for any network, we have also implemented the Firewall which provides appropriate defense for networks that prevents from internal and external threats. At the same time, the solution also provides support to Wireless LAN Controller (WLC) for providing easy manage and control all wireless access point. Keywords: Firewall, Multi-protocol Label Switching (MPLS), Servers, Virtual Private Network (VPN), Wireless LAN Controller (WLC).

There are various attack which is possible in the network, it may be from externally or internally. But internal attacks are more dangerous than external. So, my mainly concern upon Wireless LAN and Wired LAN attacks which occurs internally. There are various Signature based tools, IDS/IPS (Intrusion detection or prevention system) available now-a-days for detecting these types of attacks but these are not sufficient due to high false alarm rate. So, I detect these types of attacks with three ways: through Wireshark, with signature based tools (Snort and Kismet) and with machine learning tools (WEKA). In wired LAN attack, my mainly concern on PING scan or PING flood, NMAP scan (portsweep) and ARP spoofing attacks. In wireless LAN attacks, I take care of Deauthentication attack, Disassociation attack and Access point (AP) spoofing attack. Signature based tools detect these types of the attacks based on the stored signature and timing threshold. But machine learning tools take several different feature to detect these types of attacks with more accuracy and low false positive rate.

The enhancement of wireless technologies for machine-type communications and the Internet of things attracts the attention of recent communications research. The IEEE 802.11 task group TGah proposes to use group-based contention scheme in the MAC of its proposed amendment 11ah in order to cope with massive power constrained stations (STAs) per access point (AP). However the detailed regrouping technique is described as implementation specific. In this paper, we propose a novel method consisting of a signalling process and a regrouping algorithm. The aim of the regrouping is to minimise the potential transmission collisions caused by the hidden node problem. Firstly, the AP acquires knowledge of potential hidden node pairs and the traffic requirement of the STAs in the network. The AP then regroup the STAs into different contention groups according to either a centralised Viterbi-like algorithm or a decentralised iterative updating manner. The proposed technique can also be used in other contention based wireless networks where grouping is supported in the MAC protocol. System level simulation results show superior performance of the proposed technique in terms of the reduction in collision.

Most wireless networks are specified as layer 2 (L2), or data link protocol. Recently, IoT and big data processing have promoted the use of wireless sensor networks to connect and send data to data center applications using the Internet. To do so, the implementation of an IP stack on the wireless node, or the gateway of the IP and wireless L2 network, has been proposed. Both approaches are developed to allow the application on the IP network to access L2 wireless network nodes. However, since wireless sensor networks do not require any network protocol, an IP is not essential for collecting data. Therefore, we propose a novel bridging VPN for connecting wireless networks, in which the application and wireless end nodes are not required to acknowledge an IP address or network protocol. In this way, the IP network merely serves to transport the data link frames of wireless networks. We believe that this is another style of IoT, and recommend a small IoT businesses and institutions for use of this VPN as a test bed before they start to implement an IP stack on their systems.

Wireless network traffic explosively increased due to the increase of smart phones, tablets and IoT devices. Network users tend to prefer free WiFi over costly cellular networks. Because of this demand, people are trying to provide WiFi services in buildings or cities. This has led to the need to manage large amounts of wireless access points. However, since the AP management protocol does not exist, it is necessary to make a correction every time, which increases the time and money costs. It uses SNMP, a UDP — based network management technique, but it is not readable and stable. To solve this problem, XML-based NETCONF appeared. However, there are difficulties in development, and there is a poor performance for use with ARM processors. Therefore, in this paper, we design and propose a program structure that can process NETCONF command at ARM based wireless access point by using lightly available RPC technique.

In this paper, we present a new communication protocol for low-cost Internet-of-Things (IoT) devices that need to gather and transmit sensor data and receive remote commands. Taking into account that an IoT-network may employ different communication technologies, we define several important protocol features such as data encryption, integrity checking, sender authentication and data retransmission in case of packet delivery failures. We describe our approach to implementing each of the protocol features as part of our HybridNET system for industrial device control and communication. The hardware base includes cheap 32-bit microcontrollers, radio connectivity (SX1276 and others) and wired connectivity (mainly RS485 and Ethernet). We also describe the protocol packet structure in detail as well as our implementation for routing packets in larger IoT-networks. The experimental results are very promising and show that our protocol performs very well and delivers very good performance and reliability.

In wireless multihop networks, collisions among wireless transmission signals from the intermediate wireless nodes cause reduction of the end-to-end data message throughput. Hence, avoidance and/or reduction of collisions between 2-hop neighbor intermediate nodes due to the hidden terminal problem is required. For the disk model wireless transmissions, RH2SWL is one of efficient the solutions. However, in a wide-area wireless multihop network where a wireless multihop trans- mission route tends to be longer, the route detection ratio tends to be lower since it becomes difficult for each intermediate wireless node to detect its next-hop node. In order to solve this problem, this paper proposes a novel routing method for a wide- area wireless multihop networks based on the SIR model. The proposed routing method configures a wireless multihop transmission route where each intermediate wireless node receives wireless signal from its previous-hop intermediate wireless node without collisions with that from its next-hop wireless node. The proposed routing method improves the route detection ratio.

In ad-hoc networks, data messages are transmitted from a source wireless node to a destination one along a wireless multihop transmission route consisting of a sequence of intermediate wireless nodes. Each intermediate wireless node forwards data messages to its nexthop wireless node. Here, a wireless signal carrying the data message is broadcasted by using an omni antenna and it is not difficult for a eavesdropper wireless node to overhear the wireless signal to get the data message.

Wireless virtualization is an emerging approach to enhance the spectrum utilization by sharing wireless resources such as RF spectrum and wireless infrastructures of different networks through slicing. In this paper, we investigate RF spectrum sharing for virtual wireless networks where wireless resources for virtual networks shrink and grow based on their availability and the demands from the users. Traditional wireless network providers divide and reconfigure their RF bands to sublease to mobile virtual network operators based on service level agreements while keeping enough RF bands to their own users. We evaluate the performance of the proposed approach using percentage of RF band subleasing, outage probability and rate as metrics with the help of numerical results obtained from simulations. Note that the wireless resources are wasted if they not leased to virtual wireless network operators when they are not utilized by the owners.

Nowadays, IEEE 802.11 Wireless Local Area Networks (WLAN) has become a common technology for wireless access, making considerable progress with low cost, easy installation and mobility. This rapid rise of wireless networks has led to the design of an efficient network access protocol, which can provide high throughput for data traffic and Quality of Service (QoS) support for real-time applications, becoming one of the most important research topics in wireless networks. In this study, a novel energy-efficient network access protocol for IEEE 802.11 wireless networks was proposed. The proposed model avoids collisions by making important changes in the operational logic of wireless networks. In this context, beacon frames to be sent by the Access Points and a few bits of data to be added to ACK and CTS frames allow stations to remain in the sleep mode for the duration of time that stations will not transmit. By waking up, stations find the correct slot reserved for them, transmit frames in a collision-free environment, and achieve significant throughput increase.

The efficiency of a WiFi system with dozens of base stations in relatively small physical area is determined by the optimal allocation of the radio channels to the mobile devices. Based on the increased penetration rate of the high traffic capable smartphones and accentuated usage of these devices in densely populated buildings intelligent hardware tools are needed to offer QoS level to the users. The Radio Resource Management (RRM) of IEEE 802.11 network is provided by a wireless LAN controller. This node maintains an allocated control connection to each of the base stations providing enhanced quality level of the WiFi hot zone services. Modern base stations have the capability to listen to the radio channels periodically to detect the received signal intensity. The controller samples periodically each of the radio channels without affecting the own radio frame processing and collects in this way radio resource usage. Based on specific criteria like the number of active nodes, traffic intensity, interference, noise intensity the periodically executed RRM management algorithm modifies the distribution of active channels on the supervised hot zone level. The radio signal intensity scanning task is considered to be performed by the base stations as a sampling process of individual sensors distributed in physical space. Eighteen WiFi access points with thirteen channel sensors in 2.4 GHz range and sixteen channel sensors in 5 GHz range were used to capture radio signal intensity in a densely populated building. Holding special criteria in the scanned signal intensity values is considered as a complex event. Clustering method based on similarity measure was used to analyse sensor grouping behavior of the wireless controller RRM algorithm. Our work is focused on the usability of different statistical metrics (i.e. Hurst, Davies-Bouldin, etc.) to characterize intrusion detection efficiency of the wireless LAN controller.

The ever-increasing data demands and the density of wireless nodes require higher data rate in wireless networks. To satisfy the requirement, it is necessary to propose novel medium access control (MAC) protocols to enhance multiuser channel access and multiuser data transmission in wireless network. The existing studies prove that full-duplex (FD) is able to improve the network capability without any extra bandwidth. However, there are few studies focusing on multiuser FD MAC protocol design for the next generation wireless networks. In this paper, a multiuser FD MAC protocol named as MU-FuPlex is introduced based on our proposed system model, and the interference information collection, FD transmit opportunity (FD-TXOP) mechanism, and frame format design for MU-FuPlex are discussed. To the best of our knowledge, this is the first work focusing on the combination of multiuser MAC and FD technology. The simulation results confirm that MU-FuPlex significantly improves the saturation throughput up to 200% compared with IEEE 802.11 DCF.

We provide an empirical evaluation of an IEEE 802.11ac Wireless Local Area Network (WLAN) cell with Multiple User Multiple Input Multiple Output (MU-MIMO) technology. We conducted our experiments on a testbed comprising consumer equipment under different office scenarios using 40MHz and 80MHz channels. This is the first performance study of MU-MIMO with 802.11ac in an operational scenario using a commercial access point. We find that, for clients that do not support MU-MIMO, operating in a cell that has MU-MIMO enabled may result in reduced performance.

Nowadays, wireless LAN has become the most widely deployed technology in mobile devices for providing Internet access. As a result, WLAN users usually find themselves covered by multiple access points and have to decide which one to associate with. In traditional implementations, most wireless stations would select the access point with the strongest signal, regardless of traffic load on that access point, which might result in heavy congestion and unfair load. In this paper, we propose a novel on-line association algorithm to deal with any sequence of STAs during a long-term time such as one day.

This chapter reviews wireless communication concepts, protocols and calculations that could be applied to MEMS. The impacts of an unreliable wireless channel on the transport, network, data-link and physical layers of the protocol stack are discussed and the ways that wireless network protocols can mitigate these impacts are described. Particular attention is given to flow control, congestion control, error control, addressing mobility, radio/logical link control, medium access control, digital modulation and link budgets. The chapter ends with a template for how a physical layer system design might proceed.

In-band full-duplex radio technology enables simultaneous transmission and reception, which may double the throughput of half-duplex radio in one-to-one communication. Unfortunately, medium access control (MAC) protocols for the half-duplex radio hardly make use of the potential capacity of the full-duplex radio since simultaneous transmission and reception is limited when the receiver has no data to send. Furthermore, orthogonal frequency-division multiple access (OFDMA) is being seriously considered as a key multiple access technology for the next-generation wireless local area network (WLAN), e.g., IEEE 802.11ax. In this paper, we propose a novel MAC protocol for full-duplex OFDMA wireless networks, which extends the concurrent transmission opportunities as much as possible and resolves contention with the minimum overhead. In particular, our MAC protocol is targeted at densely populated access point based WLAN. The performance evaluation shows that our MAC significantly increases the overall network throughput compared to a recently introduced MAC for full-duplex radio.

In these days, as proliferating the use of mobile devices like tablet PC and smartphone, wireless AP should be distributed arrangement and cover a wide area by radio signal. There is the necessity of wireless AP controller because administrators of a wireless network can manage remotely and efficiently many APs on distributed area. The most of wireless AP has to use only one controller, so it may cause failure of the whole system in case of having some problem on controller managing APs. Therefore, in this paper, we propose distributed wireless AP controller using replicated key-value store called etcd. The distributed controllers connected by etcd protect the data about the managed AP, even if some controller fails. And each controller manages nearly located AP by using the way of the draft like what is uses in sports. This way using draft can reduce time to communicate between controller and APs and increase an efficiency of managing mechanism. We expect that this proposed method enhances reliability and provides high availability of wireless network managed by the controller.

In wireless multihop networks, a sequence of data messages are transmitted along a predetermined wireless multihop transmission route. Collisions among wireless transmission signals from the intermediate wireless nodes cause reduction of the end-to-end data message throughput. Hence, avoidance and/or reduction of collisions between 2-hop neighbor intermediate nodes due to the hidden terminal problem is required. For the disk model wireless transmissions in which each intermediate wireless node determines its wireless signal transmission range, RH2SWL is one of efficient the solutions. Here, a wireless multihop transmission route consists of a sequence of wireless communication links whose length becomes shorter in hop-by-hop manner. However, in a wide-area wireless multihop network where a wireless multihop transmission route tends to be longer, the route detection ratio tends to be lower since it becomes difficult for each intermediate wireless node to detect its next-hop node with its shorter wireless signal transmission range to configure a sequence of hop-by-hop shorter wireless communication links. In order to solve this problem, this paper proposes a novel routing method for a wide-area wireless multihop networks based on the SIR model. The proposed routing method configures a wireless multihop transmission route where each intermediate wireless node receives wireless signal from its previous-hop intermediate wireless node without collisions with that from its next-hop wireless node. The proposed routing method is expected to improve the route detection ratio.

Wireless local area network (WLAN) uses carrier sens multiple access with collision avoidance (CSMA/CA) to share wireless medium. However, in dense WLAN environment, it occurs interference between WLAN nodes such as access points (APs) and stations (STAs). For resolving this problem, we propose management of WLAN APs by using open network operating system (ONOS) controller which is one of software defined network (SDN) controller. Based on this, we propose a channel and transmission power control of WLAN AP in order to optimize the channel. Experimental results shows that our proposed scheme can improve performance of WLAN in terms of data rate.

In this paper, an efficient routing protocol for patient monitoring system in rural areas was proposed using wireless sensor network (WSN) so that the patients can be treated within less time. In this system, a village with GSM network is considered and the people in that village are continuously monitored using AMON sensor, an advanced medical monitoring and alert system. All the AMON's work in ADHOC region and one AMON in the village will work in GSM network acts as a gateway between the other sensors and BS. According to the patient's condition the information has to be sent to base station (BS). In this scenario, the routing of information is based on condition of the patient so on demand or reactive routing protocols are used. Different reactive routing protocols AODV, DSR are studied and modifications are done in them and compared to find the best protocol. Routing is done based on the efficient routing protocol and by simulation it is shown that the routing protocol is best in terms of throughput, end to end delay compared to other protocols.