overview of 802 11 networks
Mitigating the impact of physical layer capture and ACK interference in wireless 802 11 networks
... Figure 5.1 Achieved throughput for 802. 11n vs 802. 11n in campus WLAN Achieved throughput for 802. 11a vs 802. 11n in campus WLAN Effect of power control of data frames ... operation of 802. 11 networks 1.5 Thesis organization The rest of this thesis is organized as follows In Chapter 2, we present an overview of the existing work on interference mitigation in 802. 11 networks ... Chapter The upcoming 802. 11ac standard employs a frame aggregation scheme that is more aggressive than that of 802. 11n (maximum A-MPDU size of MB for 802. 11ac vs 64 KB for 802. 11n) Ong et al [62]...
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A Contribution to Performance Analysis Approach of the IEEE 802.11 EDCA in Wireless Multi-hop Networks
... performance of EDCA networks much better when number of node increases or with larger packet’s payload size as ftp flows networks based on IEEE 802. 11e EDCA through throughput and access delay of ACs ... analytical model which is enhanced from the model of 802. 11 DCF based on Markov chains to analyze the performance of IEEE 802. 11e EDCA in multihop networks By dividing it into two joint state models, ... characteristic parameters of IEEE 802. 11e EDCA such as CW, AIFS and virtual collision in a simple way Moreover, realistic conditions of wireless multi hop networks based on 802. 11e EDCA such as hidden...
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The study of TCP performance in IEEE 802 11 based mobile ad hoc networks
... THE STUDY OF TCP PERFORMANCE IN IEEE 802. 11 BASED MOBILE AD HOC NETWORKS LI XIA (B Sc., Nan Jing University, PRC ) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF ELECTRICAL ... over 802. 11 based ad hoc networks rather than just conducting simulations or experiments Based on the study, two schemes are proposed to improve network performance It is known that IEEE 802. 11 ... studies have also shown that, due to the spatial reuse property of 802. 11 MAC protocol in MANETs, BDP of a connection approximates 1/4 of the path length and is as low as several packets which is...
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Implementation and performance study of opportunistic network coding in 802 11 based wireless ad hoc networks using qualnet
... performance of COPE in large scale networks is also much worse than that of single-hop topologies One of the main reasons could be that the impact of COPE’s control messages on the overall performance of ... (P2P) file distribution networks to wireless ad-hoc networks, from the improvement of network capacity to increase of network security 1.5 Thesis Organization The rest of this thesis is organized ... broadcast However, one of the biggest disadvantages of 802. 11 MAC protocol is that a recipient does not send an acknowledgement in response to a broadcast packet In the absence of an acknowledgement,...
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A Contribution to Performance Analysis Approach of the IEEE 802.11 EDCA in Wireless Multi-hop Networks
... method of atomic absorption spectroscopy (AAS) in the laboratory of Meteorological and hydrological stations of the Central of Vietnam Data is processed by statistical methods, comparison of the ... 35.52 ± 15.73 g (Table 2) Content of Hg accumulated in the tissues of the Meretrix meretrix is of 0.073 ± 0.046 μg/g and the tissues of the Corbicula sp is of 0.066 ± 0.044 μg/g, not significant ... Concentrations of Hg accumulated in the tissues of both species are lower than the allowing Standard of the Ministry of Health (≤ 0.5 μg/g, 46/2007/QDBYT) However, the concentration of Hg accumulated...
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Tài liệu Guide to Securing Legacy IEEE 802.11 Wireless Networks ppt
... of WLAN technologies: IEEE 802. 11a, 802. 11b, 802. 11g, and 802. 11n In addition, a brief overview of the updated security standard for IEEE 802. 11 networks, IEEE 802. 11i, is provided 2.1 IEEE 802. 11 ... IEEE 802. 11 WLAN online resources 1-2 GUIDE TO SECURING LEGACY IEEE 802. 11 WIRELESS NETWORKS Overview of IEEE 802. 11 Wireless Local Area Networks Wireless local area networks (WLAN) are groups of ... the IEEE 802. 11 radio transmission standards and modulation techniques, such as IEEE 802. 11a, 802. 11b, and 802. 11g; any future IEEE 802. 11 standard will also be compatible with IEEE 802. 11i Table...
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OVERVIEW OF FAMILY–BUSINESS–RELEVANT ISSUES: RESEARCH, NETWORKS, POLICY MEASURES AND EXISTING STUDIES pdf
... difficulties of an ‘internal’ origin (e.g a public campaign to make owners aware of the importance of planning company transfers early) 11 3.1 Unawareness of policy makers of the specificities of family ... package) of the Ministry of Economic Affairs of the Netherlands is a unique example of this kind of measure: when the entrepreneur reaches the age of 55, he/she receives a letter reminding him/her of ... Report of the Expert Group ‘Effects of tax systems on the retention of earnings and the increase of own equity’, indicates that strengthening the equity base of companies through the retention of...
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o'reilly - 802.11 wireles networks the definitive guide
... page 132 802. 11 FH PHY 802. 11 DS PHY 802. 11b: HR/DSSS PHY 11 802. 11a: 5-GHz OFDM PHY …………………… page 169 Orthogonal Frequency Division Multiplexing (OFDM) OFDM as Applied by 802. 11a OFDM PLCP OFDM ... PMD Characteristics of the OFDM PHY 12 Using 802. 11 on Windows …………………… page 173 Nokia C110/C 111 Lucent ORiNOCO 13 Using 802. 11 on Linux …………………… page 191 A Few Words on 802. 11 Hardware PCMCIA ... standardized 802. 11g Mbps 10 Chapter Overview of 802. 11 Networks Before studying the details of anything, it often helps to get a general "lay of the land." A basic introduction is often necessary...
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building secure wireless networks with 802.11
... The 802. 11 Family of Standards 46 The 802. 11 Standard Details 46 802. 11 Security 48 Operating Modes 49 Roaming 50 The 802. 11 Extensions ... 50 The 802. 11 Extensions 50 802. 11b 50 802. 11 a 52 802. 11g 53 802. 11 Shortcomings 54 Wireless Standards Comparison ... geography of the computers on the network Some of the examples of different network types are peer−to−peer networks, local area networks, wide area networks, personal area networks, virtual private networks, ...
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802.11 wireless networks the definitive guide second edition
... Chapter 13 802. 11a and 802. 11j: 5-GHz OFDM PHY Orthogonal Frequency Division Multiplexing (OFDM) OFDM as Applied by 802. 11a OFDM PLCP OFDM PMD Characteristics of the OFDM PHY Chapter 14 802. 11g: The ... What Makes Wireless Networks Different A Network by Any Other Name Chapter Overview of 802. 11 Networks IEEE 802 Network Technology Family Tree 802. 11 Nomenclature and Design 802. 11 Network Operations ... releases of pre-standard technology Two entirely new chapters are devoted to 802. 11g and 802. 11n European adoption of 802. 11a was contingent on the development of spectrum management in 802. 11h,...
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Báo cáo hóa học: " Dynamic tuning of the IEEE 802.11 distributed coordination function to derive a theoretical throughput limit" pot
... Networking 2 011, 2 011: 105 http://jwcn.eurasipjournals.com/content/2 011/ 1/105 Page of 12 backofftime() // M: number of nodes // X: packet length // C1: the coefficient of M // C2: the coefficient of constant ... Networking 2 011, 2 011: 105 http://jwcn.eurasipjournals.com/content/2 011/ 1/105 Page of 12 Figure Coefficient of M and constant as a function of packet length CW because only one node may obtain a Backoff ... Networking 2 011, 2 011: 105 http://jwcn.eurasipjournals.com/content/2 011/ 1/105 Page of 12 Figure CW as a function of the number of nodes the packet length into Table to solve the number of nodes and...
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báo cáo hóa học: " Handoff optimization in 802.11 wireless networks" pot
... [http://www.wifly.com.tw/] doi:10 .118 6/1687-1499-2 011- 30 Cite this article as: Hsieh and Kao: Handoff optimization in 802. 11 wireless networks EURASIP Journal on Wireless Communications and Networking 2 011 2 011: 30 Submit ... Networking 2 011, 2 011: 30 http://jwcn.eurasipjournals.com/content/2 011/ 1/30 Figure 10 The overall operation flow of IP address pre-fetch and CAC Figure 11 Operation flow of AP switch Page 10 of 16 Hsieh ... functions of 802. 11e [15] have not been implemented in most APs Taking into consideration, the direction of an MN should effectively reduce handoff times In order to detect the direction of an MN...
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báo cáo hóa học: " Optimal modulation and coding scheme allocation of scalable video multicast over IEEE 802.16e networks" docx
... itself); (x11 = 1); (x11 = 1, x21 = 1); (x11 = 1, x21 = 1, x31 = 1); (x11 = 1, x21 = 1, x31 = 1, x41 = 1); (x11 = 1, x21 = 1, x31 = 1, x42 = 1); (x11 = 1, x21 = 1, x31 = 1, x43 = 1); (x11 = 1, x21 ... Communications and Networking 2 011, 2 011: 33 http://jwcn.eurasipjournals.com/content/2 011/ 1/33 Estimation of the upper bound of the objective function (i.e., total utility) at every node of the combinatorial ... specification of IEEE 802. 16e [3-5], each frame consists of subchannels and OFDMA symbols For the down link frame, a time slot, the minimum allocable resource unit, includes two consecutive OFDMA symbols...
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Báo cáo hóa học: " Research Article Design and Implementation of a Lightweight Security Model to Prevent IEEE 802.11 Wireless DoS Attacks" pdf
... NetworkLayer 8021 1 ACFNC NIC pingApp q: # Radio 8021 1 ACFNC MAC 8021 1 MgmtAP STSF Figure 5: Structure of the protected 8021 1-ACFNC-NIC in the simulation environment B the percentage of performance ... access point and wireless stations is included in the 8021 1MgmtAP-STSF and 8021 1MgmtSTASTSF sublayers, respectively The structure of the 8021 1-ACFNC-NIC for the access point including the secure ... called 8021 1-ACFNC-NIC This secure NIC includes a secure MAC layer which is called 802. 11- ACFNCMAC layer The ACFNC code to secure control frames has been written in C++ and included in the 802. 11- ACFNCMAC...
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Báo cáo hóa học: " Research Article An IEEE 802.11 EDCA Model with Support for Analysing Networks with Misbehaving Nodes" ppt
... no 6, pp 116 7 117 8, 2006 [11] K J Park, J Choi, K Kang, and Y C Hu, “Malicious or selfish? Analysis of carrier sense misbehavior in IEEE 802. 11 WLAN,” Quality of Service in Heterogeneous Networks, ... metropolitan area networks- Specific requirements—Part 11: Wireless LAN Medium Access Control(MAC) and Physical Layer (PHY) Specifications,” IEEE Std 802. 11- 2007(Revision of IEEE Std 802. 11- 1999), 2007 ... assessment of the backoff behavior of commercialIEEE 802. 11b network cards,” in Proceedings of the 26th IEEE International Conference on Computer Communications (INFOCOM ’07), pp 118 1 118 9, 2007...
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Báo cáo hóa học: " Research Article Channel Resource Allocation for VoIP Applications in Collaborative IEEE 802.11/802.16 Networks" ppt
... 802. 11e MAC layer MAC common part sublayer (MAC CPS) Security sublayer 802. 11 PHY 802. 11 PHY MAC common part sublayer (MAC CPS) Security sublayer 802. 16 PHY 802. 16 /802. 11 dual radio gateway 802. 11 ... structure of IEEE 802. 16 3.1 Device Integration of the 802. 11 and 802. 16 Networks Some radio technologies such as [12] have been developed to provide the IEEE 802. 16 and the IEEE 802. 11 connectivity ... IEEE 802. 11 /802. 16 network Numerical results are provided in Section with important conclusions drawn in Section Overview of the IEEE 802. 11 and the IEEE 802. 16 MAC Protocols 2.1 IEEE 802. 11 MAC...
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Báo cáo hóa học: " Research Article Achievable Throughput-Based MAC Layer Handoff in IEEE 802.11 Wireless Local Area Networks" pptx
... as a function of N When N > 150 which denotes that 802. 11b APs are saturated, STAs in LLF mechanism are likely to select 802. 11b APs since the loaded traffic on the 802. 11b APs ( 11 Mbps) is less ... Gigabit Ethernet AP 802. 11b channel #1 AP 802. 11b nAP channel #11 10.1.1.100 cAP 10.1.2.100 Wireless network monitor (NetMon) 10.1.1.1 s1 10.1.1.2 s2 Windows laptops (XP) 802. 11b NIC STA 10.1.2.1 ... 2, 5.5, and 11 Mbps for 802. 11b on channel 13 and CR = 6, 12, and 24 Mbps for 802. 11a on channel 44 as the STA moves away from the AP and toward the end of the corridor at intervals of meters until...
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Báo cáo hóa học: " Research Article Modified Isochronous Coordination Function for Enhancement of VoIP Call Capacity over IEEE 802.11 WLAN" pptx
... Probability of ON period Probability of OFF period Values 11 Mbps Mbps 34 bytes 24 bytes 744 μs 464 μs 464 μs 352 μs 15–19 ms 10 μs 20 μs 0.43 0.57 In ICF mode, the transmission order of every STA ... to loss ratio of 1% or less) A more important measure of the efficacy of scheme is the number of simultaneous calls while maintaining the QoS requirement Generally, a loss ratio of Table 15 ms ... IEEE 802. 11 wireless local area networks, ” IEEE Wireless Communications, vol 13, no 1, pp 22–29, 2006 [10] W Wang, S C Liew, and V O K Li, “Solutions to performance problems in VoIP over a 802. 11...
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Báo cáo hóa học: " A New MAC Protocol with Pseudo-TDMA Behavior for Supporting Quality of Service in 802.11 Wireless LANs" docx
... Prabhakaran, “A survey of quality of service in IEEE 802. 11 networks, ” IEEE Wireless Communications, vol 11, no 4, pp 6–14, 2004 [13] J Deng and R.-S Chang, “A priority scheme for IEEE 802. 11 DCF access ... Member of the academic staff of the Department of Electrical and Computer Engineering of the University of Patras and holds the position of Associate Professor Since 2004, he has been the Director of ... IEEE 802. 11 saturation throughput analysis with freezing of backoff counters,” IEEE Communications Letters, vol 9, no 2, pp 130–132, 2005 [21] S Garg and M Kappes, “On the throughput of 802. 11b networks...
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