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Artigo Revisado por pares

Apoorva Jindal, Konstantinos Psounis,

... that random access scheduling schemes, and more specifically CSMA-CA, yield exceptionally good performance in the context of wireless multihop networks. While it is believed that CSMA-CA performs significantly worse than optimal, this belief is ... we first compare the achievable rate region of CSMA-CA and optimal in a number of carefully constructed multihop topologies and find that CSMA-CA is always within 48% of the optimal. Motivated ... we next characterize the worst-case performance of CSMA-CA in neighborhood topologies representing the congested regions of ...

Tópico(s): Wireless Networks and Protocols

2012 - Institute of Electrical and Electronics Engineers | IEEE/ACM Transactions on Networking

Artigo Revisado por pares

Jae Hyun Kim, Jong Kyu Lee,

... We consider carrier-sense multiple-access/collision-avoidance (CSMA/CA) protocols as the wireless MAC protocols, since CSMA/CA protocols are based on the standard for wireless ... throughput and packet delay for three types of CSMA/CA protocols: basic CSMA/CA, stop-and-wait automatic repeat request (SW ARQ) CSMA/CA, and four-way handshake (4-WH) CSMA/CA. We calculate the capture probability of an access ... protocols. We have found that the performance of CSMA/CA in a radio channel model is 50% less ... load, while the throughput and packet delay of CSMA/CA in a radio channel model show better performance ...

Tópico(s): Advanced Wireless Network Optimization

1999 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Vehicular Technology

Artigo Revisado por pares

Hoki Baek, Jaesung Lim,

... use carrier sense multiple access with collision avoidance (CSMA/CA) protocol. However, the network performance of CSMA/CA is largely degraded in UAV-relay network systems ( ... In this paper, URNS architecture and time-mirroring CSMA/CA (TM-CSMA/CA) are proposed to satisfy these requirements. First, a ... by only using the physical layer. Second, TM-CSMA/CA guarantees that the UAV relay always wins contention ... defer time without a MAC layer. Thus, TM-CSMA/CA provides better network performance than CSMA/CA. To ...

Tópico(s): UAV Applications and Optimization

2019 - Institute of Electrical and Electronics Engineers | IEEE Systems Journal

Artigo Revisado por pares

Jianjun Lei, Dewang Tan, Xiaohan Ma, Ying Wang,

Carrier Sense Multiple Access with Collision Avoid (CSMA/CA) restricts the channel utilization efficiency although it always is regarded as a promising distributed channel access scheme, especially in dynamic dense wireless network ... hop networks. Specifically, we propose a light-weight CSMA/CA mechanism based on Q-Learning (QL), namely QL-CSMA/CA, which jointly optimizes multiple channel access parameters, including ... performance. Due to the limitation of the QL-CSMA/CA in large-scale state-space scenarios, we further ...

Tópico(s): Advanced Wireless Communication Technologies

2023 - Elsevier BV | Ad Hoc Networks

Artigo Revisado por pares

Liqiang Zhao, Jie Zhang, Hailin Zhang,

... effectively in WMNs, the authors present a hybrid CSMA/CA protocol by integrating a proposed virtual CSMA/CA and the standard CSMA/CA protocol. When a node has no packet to send, it contends for the channel in virtual CSMA/CA mode. In this way the node can estimate ... send, it contends for the channel in standard CSMA/CA mode with the optimal strategy obtained in virtual CSMA/CA mode, switching smoothly from virtual to standard CSMA/CA mode. At the same time, the node keeps ... propose a simplified game-theoretic MAC protocol (G-CSMA/CA) by designing an auto degressive backoff mechanism based ...

Tópico(s): Cooperative Communication and Network Coding

2008 - Institute of Electrical and Electronics Engineers | IEEE Network

Artigo Acesso aberto Revisado por pares

Yu Cheng, Hongkun Li, Peng‐Jun Wan, Xinbing Wang,

... practical carrier sense multiple access with collision avoidance (CSMA/CA) medium access control (MAC) protocol. We resort to ... into account the collision overhead in the distributed CSMA/CA MAC. Such overhead due to random access has ... aggressive capacity planning, which is unachievable over the CSMA/CA MAC. This paper makes the following three main ... we develop a generic method of integrating the CSMA/CA MAC analysis with the MCF formulation for optimal ... throughput; 2) we define a new concept of CSMA/CA clique and theoretically study its relationship to a ...

Tópico(s): Cooperative Communication and Network Coding

2012 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Vehicular Technology

Artigo Revisado por pares

Hojoong Kwon, Hanbyul Seo, Seonwook Kim, Byeong Gi Lee,

... channel carrier sense multiple access with collision avoidance (CSMA/CA) protocol for orthogonal frequency division multiple access (OFDMA) systems. The CSMA/CA system in conventional single-channel operation has the ... each time instant. The OFDMA-based multi-channel CSMA/CA protocol is designed to enable the stations to ... a generalized form of the conventional single-channel CSMA/CA protocol: It allows to segment the channel bandwidth ... CSMA protocol that can emulate the multi-channel CSMA/CA protocol and then analyze its saturated throughput. The ...

Tópico(s): Bluetooth and Wireless Communication Technologies

2009 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Wireless Communications

Artigo Acesso aberto Revisado por pares

Farhan Masud, Abdul Hanan Abdullah, Gaddafi Abdul-Salaam,

... slotted-Carrier Sense Multiple Access/Collision Avoidance (TCP-CSMA/CA) scheme. The emergency traffic is handled through Emergency Traffic Class Provisioning-based slotted-CSMA/CA (ETCP-CSMA/CA) scheme. The emergency-based traffic adaptivity is provided through Emergency-based Traffic Adaptive slotted-CSMA/CA (ETA-CSMA/CA) scheme. The TCP-CSMA/CA scheme assigns a distinct, minimized and prioritized backoff ... access in Contention Access Period (CAP). The ETCP-CSMA/CA scheme delivers the sporadic emergency traffic that occurs ...

Tópico(s): Bluetooth and Wireless Communication Technologies

2019 - Public Library of Science | PLoS ONE

Artigo Acesso aberto Revisado por pares

Xin Wang, Georgios B. Giannakis,

Carrier sense multiple access with collision avoidance (CSMA/CA) has been adopted by the IEEE 802.11 standards for wireless local area networks (WLANs). Using a distributed coordination function (DCF), the CSMA/CA protocol reduces collisions and improves the overall throughput. To mitigate fairness issues arising with CSMA/CA, we develop a modified version that we term ... by employing a binary exponential backoff similar to CSMA/CA. Different from CSMA/CA, CSMA/CCA copies the contention window (CW) size ...

Tópico(s): Cooperative Communication and Network Coding

2006 - Springer Nature | EURASIP Journal on Wireless Communications and Networking

Artigo Acesso aberto Revisado por pares

Fasee Ullah, Abdul Hanan Abdullah, Gaddafi Abdul-Salaam, Marina Md Arshad, Farhan Masud,

... Beacon-enabled Carrier-Sense Multiple Access/Collision-Avoidance (CSMA/CA) scheduling access scheme in WBAN, allocates Contention-free ... data.Also, a Contention Differentiated Adaptive Slot Allocation CSMA-CA (CDASA-CSMA/CA) for scheduling access scheme is proposed to reduce ... resolve the patient's data drops in the CSMA/CA scheme due to exceeding of threshold values in ... over the IEEE 802.15.4 MAC and CSMA/CA scheme in terms of success rate, packet delivery ...

Tópico(s): Bluetooth and Wireless Communication Technologies

2017 - Korea Society of Internet Information | KSII Transactions on Internet and Information Systems

Artigo

M. P. R. S. Kiran, P. Rajalakshmi,

... compared to carrier sense multiple access-collision avoidance (CSMA/CA). In this paper, we first propose a novel Markov-chain-based analytical model for unslotted CSMA/CA and PCA for industrial applications. The unslotted model ... extended to derive the analytical model for slotted CSMA/CA and PCA. Primary emphasis is laid on understanding the performance of PCA compared to CSMA/CA for different traffic classes in industrial applications. The ... delay and power consumption respectively compared to slotted CSMA/CA, whereas unslotted PCA achieves a delay reduction of ...

Tópico(s): Wireless Body Area Networks

2018 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Industrial Informatics

Artigo Acesso aberto Revisado por pares

Mahmoud Gamal, Nayera Sadek, Mohamed R. M. Rizk, Magdy A. Ahmed,

... employs carrier sense multiple access with collision avoidance (CSMA/CA) protocol to access the network using either unslotted ... slotted mode. This paper concentrates on the unslotted CSMA/CA where the node tends to wait for a ... average delay are high. To enhance the unslotted CSMA/CA performance, this paper proposes a modified unslotted CSMA/CA that divides the backoff delay into Main Backoff ... Secondary Backoff. The Markov model for the modified CSMA/CA is presented to assess a single hop IEEE ... energy consumption and reliability constraints for the modified CSMA/CA. OPNET simulation tool is applied to compare the ...

Tópico(s): Mobile Ad Hoc Networks

2020 - Elsevier BV | Alexandria Engineering Journal

Artigo

Jo Woon Chong, Youngchul Sung, Dan Keun Sung,

... into multiband carrier sense multiple access/collision avoidance (CSMA/CA) networks is proposed to provide strict quality of ... users are provided with best-effort service using CSMA/CA modified for multiband operation. The performance of the ... MAC scheme is investigated using a new multiband CSMA/CA Markov chain model capturing the primary user activity ... function of the primary user activity and other CSMA/CA parameters. It is shown that the new MAC ... yields larger throughput than the conventional single-band CSMA/CA when both schemes use the same bandwidth.

Tópico(s): Cognitive Radio Networks and Spectrum Sensing

2009 - Institute of Electrical and Electronics Engineers | Journal of Communications and Networks

Artigo Revisado por pares

Chang Woo Pyo, Hiroshi Harada,

... is based on the hybrid multiple access of CSMA/CA and TDMA. In order to study the throughput ... affected by the length of access time of CSMA/CA. A large length of access time of CSMA/CA will cause a low data transmission time in ... while a short length of access time of CSMA/CA will cause a large number of data transmission collisions in CSMA/CA. The failure of data transmission channel release due ... release and provide the optimum access time of CSMA/CA, thereby maximizing the throughput. The proposed method can ...

Tópico(s): Bluetooth and Wireless Communication Technologies

2009 - Institute of Electrical and Electronics Engineers | IEEE Journal on Selected Areas in Communications

Artigo

Fayez Gebali, A.J. Al-Sammak,

... the carrier sense multiple access with collision avoidance (CSMA/CA) protocol. To simplify the analysis, a new backoff ... analysis is used for modelling the proposed CC-CSMA/CA protocol. The resulting model describes the regular CSMA/CA protocol as a special case. Protocol performance measures ... and channel utilisation. It is found that CC-CSMA/CA offers improvements over a system that uses CSMA/CA.

Tópico(s): Distributed systems and fault tolerance

2006 - Institution of Engineering and Technology | IEE Proceedings - Communications

Artigo Acesso aberto Revisado por pares

Feng Xia, Jie Li, Ruonan Hao, Xiangjie Kong, Ruixia Gao,

... 4 slotted Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) employs static parameter configuration without supporting differentiated services ... proposes a priority‐based Service Differentiated and Adaptive CSMA/CA (SDA‐CSMA/CA) algorithm to provide differentiated QoS for various Smart ... conditions. Simulation results demonstrate that the proposed SDA‐CSMA/CA scheme significantly outperforms the IEEE 802.15.4 slotted CSMA/CA in terms of effective data rate, packet loss ...

Tópico(s): IoT Networks and Protocols

2013 - Hindawi Publishing Corporation | The Scientific World JOURNAL

Artigo Revisado por pares

Negar Kiyavash, Farinaz Koushanfar, Todd P. Coleman, Mavis Rodrigues,

... used carrier sense multiple access with collision avoidance (CSMA/CA) protocol. The spyware components are embedded within the ... spied data. Our codes are robust against the CSMA/CA's random retransmission time for collision avoidance and ... tested on a widely used open-source wireless CSMA/CA radio platform. We identify the following performance metrics ... 2) robustness of the communication scheme to heterogeneous CSMA/CA effects; and 3) difficulty of covert channel detection. ... Criterion 2) is evaluated by simulating a wireless CSMA/CA architecture and testing the robustness of the decoder ...

Tópico(s): Internet Traffic Analysis and Secure E-voting

2013 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Information Forensics and Security

Artigo Revisado por pares

Osama Bazan, Muhammad Jaseemuddin,

... the directional carrier sense multiple access/collision avoidance (CSMA/CA) protocols encounter unprecedented challenges that can offset this ... analytically studied since existing analytical models for directional CSMA/CA ignore the effect of deafness. In this study, the authors develop an analytical framework for directional CSMA/CA, which is the first analytical model to consider ... between spatial reuse and deafness when a directional CSMA/CA protocol is employed. Their results demonstrate that decreasing ...

Tópico(s): Mobile Ad Hoc Networks

2010 - Institution of Engineering and Technology | IET Communications

Artigo Acesso aberto Revisado por pares

Sumit Kumar Singh, Prashanth Aravinda Kumar Acharya, Upamanyu Madhow, Elizabeth M. Belding‐Royer,

... insensitive traffic, assuming a narrowband physical layer with CSMA/CA capabilities. The VoIP call carrying capacity of wireless mesh networks based on classical CSMA/CA (e.g., the IEEE 802.11 standard) is ... to implement. In this paper, we introduce Sticky CSMA/CA, a new medium access mechanism that provides TDM- ... gains. Nodes monitor the medium using the standard CSMA/CA mechanism, except that they remember the recent history ...

Tópico(s): Cooperative Communication and Network Coding

2007 - Elsevier BV | Ad Hoc Networks

Artigo Revisado por pares

Feiran Wang, Yuping Zhao, D. Li,

... specifications, employing carrier sense multiple access/collision avoidance (CSMA/CA) strategies, represents a significant milestone in promoting deployment ... authors first analyse the performance of the slotted CSMA/CA strategy specified in the contention access period (CAP) ... used to analyse the performance of the unslotted CSMA/CA strategy specified in IEEE 802.15.4 as well as that of the slotted CSMA/CA strategy. Extensive simulations demonstrate the accuracy and effectiveness ...

Tópico(s): Energy Efficient Wireless Sensor Networks

2011 - Institution of Engineering and Technology | IET Communications

Artigo Revisado por pares

Qin Liu, Yanan Chang, Xiaohua Jia,

... in contention-based wireless sensor networks that use CSMA/CA MAC layer protocols as defined in IEEE 802. ... all sensor nodes within the delay bound. In CSMA/CA protocols, the success probability and the expected transmission ... We propose a hybrid method that combines the CSMA/CA protocol with TDMA scheduling of transmissions. We divide ... Within the group, the nodes still use the CSMA/CA protocol to compete for data transmission. By doing ...

Tópico(s): Wireless Networks and Protocols

2012 - Elsevier BV | Computer Communications

Artigo Acesso aberto Revisado por pares

Bharat Shrestha, Ekram Hossain, Kae Won Choi,

... of carrier-sense multiple access with collision avoidance (CSMA/CA) can be combined with that of time-division ... area networks. In particular, the performance of legacy CSMA/CA-based medium access control scheme in congested networks can be enhanced through a hybrid CSMA/CA-TDMA scheme while preserving the scalability property. In ... distributed channel access scheme outperforms the legacy slotted CSMA/CA scheme. The centralized model outperforms the distributed model ...

Tópico(s): Energy Efficient Wireless Sensor Networks

2014 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Wireless Communications

Artigo Acesso aberto Revisado por pares

Kyou Jung Son, Sung‐Kwon Hong, Seong-Pil Moon, Tae‐Gyu Chang, Hanjin Cho,

... improving carrier sense multiple access with collision avoidance (CSMA/CA). Improving CSMA/CA is important because the low-power consumption feature ... IEEE 802.15.4 are greatly affected by CSMA/CA behavior. To improve the performance of CSMA/CA, this paper focused on increasing the chance to ... method used in CCA, which is employed by CSMA/CA, assesses the channel by measuring the energy level ...

Tópico(s): Mobile Ad Hoc Networks

2016 - Multidisciplinary Digital Publishing Institute | Sensors

Artigo Acesso aberto Revisado por pares

Pervez Khan, Niamat Ullah, Farman Ali, Sana Ullah, Youn-Sik Hong, Lee Ki-Young, Hoon Kim,

The Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) procedure of IEEE 802.15.6 Medium Access ... packet collisions. Therefore, The IEEE 802.15.6 CSMA/CA has developed the ABEB procedure to avoid the ... chain to design the PFB scheme for the CSMA/CA procedure of the IEEE 80.15.6 standard. ... is compared against the ABEB function of WBAN CSMA/CA. The results show that the PFB procedure adopted for IEEE 802.15.6 CSMA/CA outperforms the ABEB procedure.

Tópico(s): Bluetooth and Wireless Communication Technologies

2017 - Multidisciplinary Digital Publishing Institute | Sensors

Artigo Acesso aberto Revisado por pares

Nurullah Shahin, Rashid Ali, Young‐Tak Kim,

... on carrier-sense multiple access with collision avoidance (CSMA/CA), was analyzed as not efficient enough for registration ... In this paper, we propose a hybrid slotted-CSMA/CA-time-division multiple access (TDMA) (HSCT) medium access ... AP. In the proposed HSCT, contention-based slotted-CSMA/CA allows devices to send an authentication request via ... scheme, and the conventional IEEE 802.11ah with CSMA/CA.

Tópico(s): Wireless Networks and Protocols

2018 - Institute of Electrical and Electronics Engineers | IEEE Access

Artigo Acesso aberto

Bin Cao, Mengyang Li, Lei Zhang, Yixin Li, Mugen Peng,

... MAC mechanism, carrier sense multiple access/collision avoidance (CSMA/CA), is suitable for wireless blockchain networks or not. ... impact of queueing and transmission delay caused by CSMA/CA. Next, a stochastic model is proposed to analyze ... the performance would be limited by the traditional CSMA/CA protocol. Meanwhile, we demonstrate that the probability of ... successful double-spending attack would be affected by CSMA/CA as well.

Tópico(s): IoT and Edge/Fog Computing

2019 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Industrial Informatics

Artigo Acesso aberto Revisado por pares

Farhan Masud, Abdul Hanan Abdullah, Ayman Altameem, Gaddafi Abdul-Salaam, Farkhana Muchtar,

... based Carrier Sense Multiple Access/Collision Avoidance (TCP-CSMA/CA) scheme for prioritized channel access to heterogenous-natured ... class in every backoff during contention. In TCP-CSMA/CA, the BMSNs are distributed among four traffic classes ... out to determine the performance of the TCP-CSMA/CA in terms of packet delivery delay, throughput, PDR, ... consumption. The results prove that the proposed TCP-CSMA/CA scheme performs better than the IEEE 802.15. ...

Tópico(s): Molecular Communication and Nanonetworks

2019 - Multidisciplinary Digital Publishing Institute | Sensors

Artigo Revisado por pares

Yohan Kwon, Hoki Baek, Jaesung Lim,

... of carrier sense multiple access with collision avoidance (CSMA/CA) by increasing packet collisions with the number of ... are no previous studies on uplink NOMA in CSMA/CA networks. In the considered system, owing to the ... medium access control procedure for uplink NOMA with CSMA/CA is also presented. The analytic results demonstrate that ... saturation throughput and average packet delay than conventional CSMA/CA.

Tópico(s): Satellite Communication Systems

2020 - Institute of Electrical and Electronics Engineers | IEEE Systems Journal

Artigo Revisado por pares

Liu Bo, Shiying Han, Huyang Peng, Zihao Xiang, Guiling Sun, Ying‐Chang Liang,

... to the access point (AP) according to the CSMA/CA protocol while receiving the information from their respective ... only decreases the PHY-layer SINR of the CSMA/CA system, but also increases its failure probability of ... affected by the MAC-layer activity of the CSMA/CA system. To this end, we analyze the cross- ... layer outage capacities of the BD and the CSMA/CA systems. Simulation results are provided to verify our ... the interaction between the BD and the ambient CSMA/CA systems.

Tópico(s): Advanced Wireless Communication Technologies

2020 - Institute of Electrical and Electronics Engineers | IEEE Wireless Communications Letters

Artigo Revisado por pares

Achour Achroufene, Mourad Chelik, Nassima Bouadem,

... the Carrier-Sens Multiple Access with Collision Avoidance (CSMA/CA) protocol. In this article, a modified CSMA/CA is proposed to meet the requirements of the ... the found results. Compared to the use of CSMA/CA as implemented in Contiki, using the proposed modified CSMA/CA in both data fusion applications improves QoS.

Tópico(s): Water Quality Monitoring Technologies

2021 - Elsevier BV | Computer Networks