Cross-layer multi channel MAC protocol for interference mitigation

In multi-channel WLANs, the MAC protocol allocates a channel to each transmission pair while avoiding interference. In the channel allocation phase, if the MAC protocol allocates one channel iteratively to multiple narrowly spaced transmission pairs, both channel utilization and network throughput can be improved. However, such an approach leads to traffic overload; thus, if a transmission takes place over a transmission channel, the number of terminals that can receive the transmission decreases. B-MAC, a multi-channel MAC protocol designed for broadcast, starts a new broadcast transmission after waiting for a certain period of time; however, this waiting time increases the transmission overhead and degrades channel utilization. In this paper, we propose CA-BMAC, a new multi-channel MAC protocol that reduces the waiting time associated with B-MAC, and thus, the transmission overhead. Performance evaluations of the proposed protocol clarify its advantages over B-MAC.

In high diversity node situation, single-channel MAC protocols suffer from many collisions. To solve this problem, the research of multichannel MAC protocol has become a hotspot. And the cyclic quorum-based multichannel (CQM) MAC protocol outperformed others owing to its high frequency utilization. In addition, it can avoid the bottleneck that others suffered from and can be easily realized with only one transceiver. To obtain the accurate performance of CQM MAC protocol, a Markov chain model, which combines the channel hopping strategy of CQM protocol and IEEE 802.11 distributed coordination function (DCF), is proposed. The metrics (throughput and average packet transmission delay) are calculated in performance analysis, with respect to node number, packet rate, channel slot length and channel number. The results of numerical analysis show that the optimal performance of CQM protocol can be obtained in saturation bound situation. And then we obtain the saturation bound of CQM system by bird swarm algorithm (BSA). Finally, the Markov chain model and saturation bound are verified by Qualnet platform. And the simulation results show that the analytic and simulation results match very well.

Recent research has demonstrated the feasibility of full-duplex (FD) communication over the same frequency channel. This capability, facilitated by new self-interference suppression techniques, has great potential to increase the network capacity. However, exploiting FD in the context of a multi-user, multi-channel network is still being debated. This paper focuses on the channel access issue and presents a novel multi-channel MAC (MMAC) protocol for wireless ad hoc networks with FD and orthogonal frequency-division multiple access (OFDMA) capabilities. Through these capabilities, a node can simultaneously carry out multiple transmissions and/or receptions over the same or different channels. In our MMAC protocol, a pair of nodes negotiate data channels, transmission rates, transmission powers, and transmission modes (e.g., FD or half-duplex) in a distributed manner so that their spectral usages are minimized while their rate demands are still met. Extensive ns3 simulations show that our MMAC protocol increases the end-to-end network goodput by up to 150% and decreases the end-to-end delay by up to 300% compared with an OFDMA-based protocol without FD.

A number of multichannel MAC protocols have been developed earlier with the objective of maximizing energy efficiency and guaranteeing QoS requirements in wireless sensor networks. However, the trade-off between energy efficiency and QoS requirements remains an open issue. In this paper, we propose a multichannel MAC protocol so that nodes dynamically switch their interface between the channels to achieve this goal. The proposed protocol works in two phases, the advertisement (ADV) phase and data phase, which run concurrently. During the ADV phase, the nodes having data try to contend the advertisement channel to transmit the ADV packet. The nodes after receiving the acknowledgement from the receiver switch to the available free channel for the transmission of data packet. We analyze the performance of our proposed protocol through simulation. The simulation results reveal the proposed protocol performs better than the existing MAC protocols in terms of data delivery ratio, end-to-end delay and energy efficiency.

In this paper, an interference and throughput aware multi-channel MAC protocol (ITMMAC) is designed for actor-actor coordination in wireless sensor-actor networks (WSAN). Each actor consists of multiple transceivers, hence it can simultaneously transmit or sense on multiple non-interference channels. ITMMAC protocol divides the beacon interval into ad-hoc traffic indication message (ATIM) window and data transmission phase. In the ATIM window, sender negotiates the minimum interference and maximum throughput channel among the available channels with the destination. Each actor processes the channel negotiation phase in the dedicated control channel. The proposed ITMMAC protocol is simulated using NS2. The obtained simulation results are analyzed using network parameters such as average throughput and average packet delay in the network. The simulation results indicate that the proposed ITMMAC protocol performs well as compared to the existing MAC protocols.

Recently, many MAC protocols have been proposed for effective communication in the single transceiver multi-channel environment. In these MAC protocols, however, the multi-channel hidden terminal problem degrades the throughput of the communication systems. In order to mitigate the effects of the multi-channel hidden terminals, two MAC protocols have been proposed: cooperative asynchronous multi-channel MAC (CAM-MAC), where neighbouring terminals inform a sender of its bad channel selection and virtual topology MAC (VT-MAC), where redundant channel usage information is reduced by considering the network topology. However, these MAC protocols mainly focus on avoiding bad channel selections by the sender, and not on increasing good channel selections (concurrent transmissions). Therefore, in this paper, to further improve throughput performance by concurrent transmissions, we propose new multi-channel MAC protocols in which neighbour terminals of a sender recommend a better transmission channel prior to the data transmission. The performance evaluations verify that the proposed MAC protocol effectively improves the throughput performance when compared to existing MAC protocols, especially when the channel negotiation process induces the larger overhead at the short data transmission.

This paper mainly introduces the application of multichannel communication technology in wireless sensor network. The corresponding solutions are proposed based on the analysis of the structure and characteristics of wireless sensor, and the multi-channel MAC protocol in wireless sensor network. In this paper, multi-channel communication technology in wireless sensor network (WSN) is studied, the existing problems and reasons are analysed, and some solutions to further promote the further development of the technology are put forward. With the wide application of WSN, the security of WSN has been paid more and more attention. In this paper, the existing time synchronization protocol, from the security point of view, and the fault tolerance design of the fits protocol. The protocol has an intrusion detection mechanism, which can detect the attack of malicious nodes in time synchronization. Aiming at the small deviation of slow attack and the problem of time synchronization error, information fusion is based on the quality principle, and according to the time synchronization information of different nodes, we make random weighted average correction for local time nodes. The simulation results show that the fits time synchronization protocol has good intrusion detection and fault tolerance capability.

A vehicular ad hoc network (VANET) is designed to enable efficient and authentic node/infrastructure communication. The primary role of VANETs is to distribute time-sensitive safety messages (sm) regularly, which causes packet congestion and broadcast failure due to the network’s limited spectrum. For efficient and reliable delivery, the proposed paper uses a spatial hybrid division multiple access (SDMA) and time division multiple access (TDMA) over the control channel interval and hence termed a spatially distributed multichannel MAC (SDM-MAC) protocol. The frequency reuse approach is used to transfer data while efficiently utilising bandwidth, and throughput is considerably enhanced with carrier sense multiple access with collision avoidance (CSMA/CA) and with the help of TDMA. Moreover, an adaptive algorithm is proposed for an intelligent channel frame structure using this protocol to manage the highly dynamic scenario. The Markov chain defines the protocol, and the network simulator (NS2) analyses several performance metrics. Comparing the response with two existing MAC protocols, the proposed protocol reduces average latency compared to current MAC methods and improves the packet delivery ratio and throughput by an average of 26% and 28%, respectively.

CogMOR-MAC: A cognitive multi-channel opportunistic reservation MAC for multi-UAVs ad hoc networks

The smart grid incorporates a two-way communication system between customers and the utility for advanced monitoring and intelligent control of supply and demand. Wireless multimedia sensor network can be treated as an organic supplement and a peripheral network in this two-way communication system. However, the challenging smart grid environment makes it difficult to achieve a high quality of service in wireless multimedia sensor network. This article proposes a prioritization mechanism that considers the heterogeneous characteristics of smart grid traffic. Specifically, an innovative channel allocation and traffic scheduling scheme, named the preemptive tidal flow queuing model, is presented. This scheme achieves differentiated services for diverse communication data when the wireless multimedia sensor network accesses the core network and ensures the performance for high-priority data at the expense of the performance for low-priority data. Simulation analyses show that the performance for high-priority messages can be reliably guaranteed and that the preemptive tidal flow queuing model satisfies the requirements for a wireless multimedia sensor network operating in the smart grid environment. This article offers three main contributions: the development of a prioritization mechanism specifically for a wireless multimedia sensor network in the smart grid environment, the proposal of the preemptive tidal flow queuing model, and the presentation of formulas and simulations to verify the performance of the preemptive tidal flow queuing model.

A novel multi-channel MAC protocol with directional antenna for enhancing spatial reuse and bandwidth utilization in WLANs

Energy efficiency of MAC protocols in low data rate wireless multimedia sensor networks: A comparative study

In this paper, a multi-channel preamble sampling MAC protocol, MCPS, especially designed for wireless sensor networks, is proposed and thoroughly evaluated. MCPS is a low power MAC protocol operating on multichannel using carrier sensing for collision avoidance. Specifically, MCPS exploits all the non-overlapping channels provided by IEEE 802.15.4 physical layer. Basically, MCPS uses one dedicated common control channel to wakeup an intended receiver using a preamble sampling technique. However, data transmission takes place in a dedicated data channel. In fact, MCPS allows each sensor node to dynamically adjust its transmission power when sending strobed preamble or periodically generated data. Indeed, for each possible distance separating a pair of communicating nodes, MCPS adapts the appropriate transmission power and selects the appropriate data channel. By using multiple channels, MCPS allows multiple simultaneous communications reducing hence the end-to-end delay and improving the throughput. MCPS has been implemented using OMNET++ simulator under INET framework, on top of the IEEE 802.15.4 physical layer, which it was improved to support the multi channel communication. Simulation results show that MCPS can greatly improve the network performance especially in terms of throughput and end-to-end delay.

Wireless Sensor Network (WSN) is lying to several attacks because the Black hole is problematic to distinguish and protect. Impostor internments and re-programs block the packets rather than transmitting and obtaining them at the base station (BS) in a black hole attack. Consequently, any data that arrives in the black hole area is taken and cannot reach the recipient, triggering high packet losses and decreasing network performance. To overcome this problem, a hidden Markov model with machine learning (HMML)-based black hole attack identification in WSN is introduced. This approach uses the Hidden Markov Model (HMM) to detect the blackhole node in the WSN. This model examines the shortest routes between the sender and the recipient to discover the black hole route. This model contains states as well as the observation sequence. Forward and received count and reply of non-adjacent nodes are used for verifying the shortest routes. Here, the supervised and unsupervised training machine learning methods decide for detecting black hole nodes.

The development of mobile communication services has lead to the increase the use of wireless spectrum. However, the persuasion of the overly crowded spectrum is not due to the scarcity of usable radio frequencies but to the current static spectrum management policy. This reveals many idle frequency bands in both time and space. The cognitive radio network (CRN) is a key solution to exploit the existing spectrum dynamically. In this paper, we propose a new Reactive Multi-Channel cognitive MAC protocol (RMC-MAC) that integrates a novel cooperative sensing scheme which reliably detects the presence of incumbents even if the secondary users are transmitting. Then, a recovery scheme is proposed to ensure the continuity of SU transmission and to reduce the forced termination probability. This recovery solution also shows that bandwidth utilization is higher than the one achieved by a common protocol without handoff and another buffering based protocol.