ieee 802 11 wireless local area networks ppt

... and 802. 1X 16 Bernard Aboba, Microsoft, Wireless LANS: the 802. 1X Revolution, Dec 2001. 17 Nokia C110/C 111 802. 11b cards support station-unique WEP keys. Hardening IEEE 802. 11 wireless networks ... Hardening IEEE 802. 11 wireless networks Hardening IEEE 802. 11 wireless networks January 2002 Tyson Macaulay, Director, PKI and Wireless Security EWA Canada www.ewa-canada.com www.ewa.com Hardening IEEE ... January 15, 2002 Tyson Macaulay Hardening IEEE 802. 11 wireless networks Copyright EWA Canada 2002 1 1 Introduction IEEE 802. 11 is a Wireless Local Area Network (WLAN) standard which specifies

Ngày tải lên: 08/08/2014, 09:22

... wireless local area networks (WLANs), and wireless personal area networks (WPANs). The IEEE standards association establishes five standard series of IEEE 802. 22, 802. 20, 802. 16, 802. 11, and 802. 15 ... coverage, wireless networks can in general be divided into five different categories, including wireless regional area networks (WRANs), wireless wide area networks (WWANs), wireless metropolitan area networks ... protocol data unit (A- MPDU), are exploited in the current IEEE 802. 11n draft. Per- formance comparisons between IEEE 802. 11, 802. 11e, and 802. 11n protocols have been presented in [10]. The benefits

Ngày tải lên: 21/06/2014, 17:20

... of IEEE 802. 11a, IEEE 802. 11b, and IEEE 802. 11g technologies support the max- imum PHY data rates of 54 Mbps, 11 Mbps, and 54 Mbps, respectively [2–4]. All these PHY variants of IEEE 802. 11 wireless ... is 9 microseconds in IEEE 802. 11a wireless LANs. In Figures 4, 5, 6, 7, 8, 9, 10, 11, and12, we present the simulation results of the maximum delay bounds of IEEE 802. 11a wireless LAN with the ... Dong-A University. REFERENCES [1] IEEE Std 802. 11, ? ?Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications,” 1999. [2] IEEE Std 802. 11a, ? ?Wireless LAN Medium Access Control

Ngày tải lên: 21/06/2014, 23:20

... The IEEE 802. 11 protocol is emerging as a w idely used standard and has become the most mature technology for wireless local area networks (WLANs). In this paper, we focus on the tuning of the IEEE ... IEEE 802. 11b, 1999 [4] IEEE, Ieee standard for wireless LAN medium access control (MAC) and physical layer (PHY) specification: higher-speed physical layer in the 5 GHz band,” IEEE 802. 11a, ... specifications,” ISO/IEC 8802- 11: 1999(E), 1999 [3] IEEE, IEEE standard for wireless LAN... Atlanta, Ga, USA, November 2003 [10] F Cali, M Conti, and E Gregori, IEEE 802. 11 protocol: design

Ngày tải lên: 23/06/2014, 00:20

... considered as an original contribution to the area of EDCA models and backoff misbehaviour Introduction The IEEE 802. 11 standard [1] for wireless local area networks (WLANs) does not provide users with ... dropped Table contains the standard values of the EDCA parameters for IEEE 802. 11 HR/DSSS (known as 802. 11b) [1] Furthermore, for 802. 11b the standard defines NC = 4, M equal to or (depending on frame ... attack,” IEEE/ ACM Transactions on Networking, vol 14, 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

Ngày tải lên: 21/06/2014, 11:20

... the IEEE 802. 11 and the IEEE 802. 16 MAC protocols, frame structures, and proposed to embed multiple IEEE 802. 16 frames into a IEEE 802. 11 frame by using CAPs in the IEEE 802. 11e frame for the IEEE ... collaborative 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 ... the IEEE 802. 11 and IEEE 802. 16 Networks In addition to the coexistence that is considered in most of situations, we further consider collaboration between the IEEE 802. 11 and the IEEE 802. 16 networks

Ngày tải lên: 21/06/2014, 11:20

... two extremes. 12.1 Nokia C110/C 111 Nokia's 802. 11b solution comes in two similar form factors. The C110 is a Type 2 PC Card with an integrated antenna; the C 111 is basically the same, ... encoding of Schiller's Ode to Joy for transmission over an 802. 11a network. [2] Shortly after 802. 11a was published, the IEEE 802. 11 working group discovered several errors in the example ... explain the non-Ethernet driver features in some detail. I selected two 802. 11 cards as examples: the Nokia C110/C 111 and the Lucent ORiNOCO. While not particularly common, the Nokia card

Ngày tải lên: 14/08/2014, 13:20

... The IEEE 802. 11e standard has been introduced to support service differentiation for wireless local area networks. In wireless multi-hop networks, the performance of IEEE 802. 11e EDCA has to ... IEEE 802. 11 EDCA in Wireless Multi-hop Networks Minh Trong Hoang*, Minh Hoang, Duc Cong Le Posts and Telecommunications Institute of Technology, Hanoi, Vietnam Abstract The IEEE 802. 11e ... Keywords: IEEE 802. 11e EDCA, Virtual collision, Multi-hop network, Hidden node, Markov chain. 1. Introduction The IEEE 802. 11 has become ubiquitous and gained widespread popularity for wireless

Ngày tải lên: 13/08/2015, 10:00

... been introduced to support service differentiation for wireless local area networks In wireless multi-hop networks, the performance of IEEE 802. 11e EDCA has to confront with some practical problems ... the IEEE 802. 11 EDCA in Wireless Multi-hop Networks Minh Trong Hoang*, Minh Hoang, Duc Cong Le Posts and Telecommunications Institute of Technology, Hanoi, Vietnam Abstract The IEEE 802. 11e standard ... IEEE 802. 11e EDCA, Virtual collision, Multi-hop network, Hidden node, Markov chain Introduction The IEEE 802. 11 has become ubiquitous and gained widespread popularity for wireless multi-hop networks

Ngày tải lên: 17/03/2021, 20:27

... and DFS ► IEEE? ?802. 11i: Supplementary MAC Standard: Alternative WEP ► IEEE? ?802. 11n: 100 +Mbps : Enhancement to 802. 11g using MIMO ► IEEE? ?802. 11s : mesh networking extension IEEE 802. 11 Architecture ... Wireless Networks Lecture 26 Wireless LAN / IEEE 802. 11 Dr Ghalib A Shah Outlines      Overview of IEEE 802. 11 IEEE 802. 11 Protocols Architecture Services ... Point Coordination Function (PCF) Distributed Coordination Function (DCF) 802. 11 2.4 GHz FHSS 802. 11 2.4 GHz DSSS 802. 11 Ird 802. 11a 5 GHz OFDM 802. 11b 2.4 GHz DSSS 19 802. 11g 2.4 GHz OFDM Reliable Data Delivery  Reliability

Ngày tải lên: 05/07/2022, 13:17

... Wireless Networks Lecture 29 Security in IEEE 802. 11 Dr Ghalib A Shah Outlines       Types of Attack Goals of 802. 11 Security WEP Protocol WEP Authentication ... Allows real-time automated decryption of all traffic 802. 11 Security  Goals of 802. 11 security ► Ac c e s s  Co ntro l • Ensure that your wireless infrastructure is not used ► Data Inte g rity ... Controlled port 802. 1X • created to control access to any? ?802? ?LAN • used as a transport for Extensible Authentication Protocol  (EAP, RFC 2284) 19 AKM Operation with AS  Prior to any use of IEEE 802. 1X, IEEE

Ngày tải lên: 05/07/2022, 13:18

... RESEARCH Open Access Handoff optimization in 802. 11 wireless networks IP Hsieh and Shang-Juh Kao * Abstract In 802. 11 wireless networks, a complete handoff procedure for a mobile node ... point selection in IEEE 802. 11 wireless networks ACM Sigcomm IMC, Berkeley 2005 18 Fukuda Y, Fujiwara A, Tsuru M, Oie Y: Analysis of access point selection strategy in wireless LAN Vehicular ... and CAC. Figure 11 Operation flow of AP switch. Hsieh and Kao EURASIP Journal on Wireless Communications and Networking 2 011, 2 011: 30 http://jwcn.eurasipjournals.com/content/2 011/ 1/30 Page 10

Ngày tải lên: 21/06/2014, 02:20

... and 802. 11 Chapter 10. The ISM PHYs: FH, DS, and HR/DS Section 10.1. 802. 11 FH PHY Section 10.2. 802. 11 DS PHY Section 10.3. 802. 11b: HR/DSSS PHY Chapter 11. 802. 11a: ... products The 802 .11 b 2.4 GHz most common 802 .11 equipment as this book was 11 Mbps written up to 54 802 .11 g 2.4 GHz Not yet standardized Mbps Chapter 2 Overview of 802 .11 Networks Before ... layer of the 802. 11 standard in detail. 802. 11, like all IEEE 802 networks, splits the MAC-layer functionality from the physical medium access. Several physical layers exist for 802. 11, but the

Ngày tải lên: 14/08/2014, 13:20

... CF-Ack (no data transmitted) 0110 CF-Poll (no data transmitted) 0111 Data+CF-Ack+CF-Poll (Frame type 11 is reserved) [a] Management subtypes 0110 - 0111 and 110 1 -111 1 are reserved and not currently ... (PS)-Poll 1 011 RTS 110 0 CTS 110 1 Acknowledgment (ACK) 111 0 Contention-Free (CF)-End 111 1 CF-End+CF-Ack Data frames (type=10) [c] 0000 Data 0001 Data+CF-Ack 0010 Data+CF-Poll 0 011 Data+CF-Ack+CF-Poll ... of Higher-Layer Protocols Within 802. 11 Like all other 802 link layers, 802. 11 can transport any network-layer protocol. Unlike Ethernet, 802. 11 relies on 802. 2 logical-link control (LLC) encapsulation

Ngày tải lên: 14/08/2014, 13:20

... Bohr In wireless networks, the word "broadcast" takes on an entirely new meaning. Security concerns have haunted 802. 11 deployments since the standardization effort began. IEEE& apos;s ... 8.2 of 802. 11. WEP can be used by stations to protect data as it traverses the wireless medium, but it provides no protection past the access point. Many of the headlines about 802. 11 over ... buffering. 4.3.4.2 Probe Request Mobile stations use Probe Request frames to scan an area for existing 802. 11 networks. The format of the Probe Request frame is shown in Figure 4-40. All fields

Ngày tải lên: 14/08/2014, 13:20

... the new access point. 802. 11 does not specify the communication between access points; filling in this omission is one of the major standardization efforts in the 802. 11 working group. At the ... or simply on. Power conservation in 802. 11 is achieved by minimizing the time spent in the latter stage and maximizing the time in the former. However, 802. 11 accomplishes this without sacrificing ... of time as in infrastructure networks. As in infrastructure networks, power management in independent networks is based on traffic indication messages. Independent networks must use a distributed

Ngày tải lên: 14/08/2014, 13:20

... sense. 802. 11 does not specify how to determine whether a signal is present; vendors are free to innovate within the required performance constraints of the standard. 802. 11 requires that 802. 11- compliant ... band, though wider bands require a higher chip rate. 10.2.1.1 802. 11 direct-sequence details For the PN code, 802. 11 adopted an 11- bit Barker word. Each bit is encoded using the entire Barker ... Start of Frame Delimiter (SFD) In the long PLCP, the SFD is the sequence 111 1 0 011 1010 0000 As with all IEEE specifications, the order of transmission from the physical interface is

Ngày tải lên: 14/08/2014, 13:20

... Wireless Communications Low Rate Wireless Personal Area Networks Objectives • Describe a wireless personal area network (WPAN) • List the different WPAN ... Bluetooth – 802. 15.4 (ZigBee) IEEE 802. 15.1 and Bluetooth • Industry specification – Bluetooth Special Interest Group (SIG) • Defines small-form-factor, low-cost wireless radio communications • IEEE ... radio communications • IEEE licensed this wireless technology – To adapt and copy a portion of the specification as the base material for 802. 15.1 • 802. 15.1 standard – Approved in March 2, 2002

Ngày tải lên: 13/09/2012, 10:52

... Exchange, Wireless local area networks 1 Introduction In offices, homes, and public spaces, IEEE 802. 11 wire- less local area n etworks (WLANs) has been extensive ly used to provide wireless Internet ... they have no competing interests. Received: 2 February 2 011 Accepted: 11 August 2 011 Published: 11 August 2 011 References 1. IEEE Std 802. 11e, Medium Access Control (MAC) Quality of Service Enhancement ... IEEE 802. 11a WLAN with physical transmission rate of 24 Mbps. Nishio et al. EURASIP Journal on Wireless Communications and Networking 2 011, 2 011: 58 http://jwcn.eurasipjournals.com/content/2 011/ 1/58 Page...

Ngày tải lên: 21/06/2014, 01:20

... 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 Variants ... A-1 GUIDE TO SECURING LEGACY IEEE 802. 11 WIRELESS NETWORKS 2. Overview of IEEE 802. 11 Wireless Local Area Networks Wireless local area networks (WLAN) are groups of wireless networking nodes within ... 2. Overview of IEEE 802. 11 Wireless Local Area Networks 2-1 2.1 IEEE 802. 11 Variants 2-1 2.2 IEEE 802. 11 Network Components and Architectural Models 2-3 2.3 Wireless Local Area Network Range...

Ngày tải lên: 14/02/2014, 08:20