QoS-aware MAC protocols for wireless sensor networks: A survey <s> Application Specific Protocols <s> We present an innovative MAC protocol (Q-MAC) that minimizes the energy consumption in multi-hop wireless sensor networks (WSNs) and provides quality of service (QoS) by differentiating network services based on priority levels. The priority levels reflect application priority and the state of system resources, namely residual energy and queue occupancies. The Q-MAC utilizes both intra-node and inter-node arbitration. The intra-node packet scheduling is a multiple queuing architecture with packet classification and weighted arbitration. We also introduce the power conservation MACAW (PC-MACAW) - a power-aware scheduling mechanism that, together with the loosely prioritized random access (LPRA) algorithm, govern the inter-node scheduling. Performance evaluation are conducted between Q-MAC and S-MAC with respect to two performance metrics: energy consumption and average latency. Simulation results indicate that the performance of the Q-MAC is comparable to that of the S-MAC in non-prioritized traffic scenarios; when packets with different priorities are present, Q-MAC supiors in average latency differentiation between the classes of service, while maintaining the same energy level as that of S-MAC <s> BIB001 </s> QoS-aware MAC protocols for wireless sensor networks: A survey <s> Application Specific Protocols <s> This paper presents a new prioritized medium access control protocol (PSIFT) that improves the performance of event-driven wireless sensor networks by suppressing the redundant reports of sensor nodes in proximity. This suppression of similar reports results in low collision probability, shorter delay and accurate detection of events by the sink. PSIFT is a CSMA-based MAC protocol that provides traffic differentiation by varying the inter frame space and contention window size for each traffic class. We also introduce the new report suppression mechanism based on the broadcast nature of wireless transmission in PSIFT. This mechanism works very efficiently in large-scale, event-driven wireless sensor networks. Simulation results show that the new PSIFT MAC protocol can bring significant improvement in delay performance of the networks. When the sensing range grows up to transmission range, PSIFT can reduce the latency as much as three times in delivering reports as compared to the existing IEEE802.11 MAC protocol. <s> BIB002 </s> QoS-aware MAC protocols for wireless sensor networks: A survey <s> Application Specific Protocols <s> This paper presents a general framework for adaptive Energy and QoS Aware (EQoSA) MAC protocol for wireless sensor networks. It is a scheduling based MAC protocol assuming a steady state network behavior. Similar to previous works, the time is divided into rounds and each round starts with a setup phase followed by a number of sessions. Each session starts with a contention window followed by a number of slots reserved for those users who expressed their wishes to transmit packets and the cluster head approved their assignment. The proposed protocol has two unique features; the dynamic size of each session and the ability to accommodate bursty sensors by allocating more than one data slot in each session. EQoSA is so general to accommodate a wide range of wireless sensor networks applications. A discrete event driven simulation is extensively run to evaluate the proposed protocol. The proposed protocol is examined against Bit-Map MAC protocol (a modified LEACH) and it shows an outstanding improvement both in end-to-end packet delay as well as the total consumed energy. These important results make EQoSA a viable MAC protocol for real time applications such as video and imaging applications. <s> BIB003 </s> QoS-aware MAC protocols for wireless sensor networks: A survey <s> Application Specific Protocols <s> This paper introduces I-MAC, a new medium access control protocol for wireless sensor networks. I-MAC targets at improving both channel utilisation and energy efficiency while taking into account traffic load for each sensor node according to its role in the network. I-MAC reaches its objectives through prioritized and adaptive access to the channel. I-MAC performances obtained through simulations for different network topologies, scenarios and traffic loads show significant improvements in energy efficiency, channel utilization, loss ratio and delay compared to existing protocols. <s> BIB004 </s> QoS-aware MAC protocols for wireless sensor networks: A survey <s> Application Specific Protocols <s> Future application areas of wireless sensor networks (WSNs) may include industrial process automation, aircraft control systems or patient monitoring in hospitals. Such applications require predictable quality of service in terms of message transfer delay and reliability. Performance of WSN data transport is to a large extent defined by the employed medium access control (MAC) protocol. Currently, no existing MAC protocol is capable of supporting WSN applications that require deterministic data transport performance. In this paper, we present the implementation of a new WSN MAC protocol that is able to give deterministic bounds for message transfer delay and reliability. The protocol is implemented on TinyOS 2.x for a Tmote Sky node using the CC2420 transceiver. Our implementation shows that a deterministic MAC protocol with reasonable energy consumption patterns is practical. <s> BIB005 </s> QoS-aware MAC protocols for wireless sensor networks: A survey <s> Application Specific Protocols <s> Popularity of Wireless Sensor Networks (WSNs) combined with the multimedia requirements of new applications have enabled Wireless Multimedia Sensor Networks (WMSNs) which commonly carry heterogeneous traffic. In order to deliver multiple types of traffic with different requirements in highly resource constrained sensor networks, Quality of Service (QoS) provisioning becomes unavoidable. In this work, we propose Diff-MAC; a QoS-aware and priority-based MAC protocol for WMSNs. Diff-MAC aims to increase the utilization of the channel with effective service differentiation mechanisms while providing fair and fast delivery of the QoS-constrained data. Performance evaluation results of Diff-MAC, obtained through extensive simulations, show significant improvements, in terms of latency, data delivery and energy efficiency, compared to two other existing protocols. <s> BIB006
These protocols are proposed to fulfill the QoS requirements of specific applications which perform multimedia transmission, vehicular or tactical communication, etc. They try to provide hard/soft QoS bounds by employing various mechanisms such as: -Adaptation & learning -Data suppression and aggregation -Error control -Clustering E.g. BIB003 BIB005 protocols BIB002 BIB004 provide dynamic differentiation and BIB001 BIB006 propose a hybrid approach.