Wlan 802.11n - MAC Sublayer
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The document discusses the MAC sublayer in the 802.11n wireless LAN standard. It describes how the 802.11n MAC sublayer aims to improve protocol efficiency, support quality of service standards, and minimize contention overhead through techniques like selective retransmission. It also examines how the 802.11n MAC protocol operates in different modes and addresses problems like hidden and exposed nodes through physical and virtual sensing methods.
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Wireless LANs PPT.ppt
A wireless LAN or WLAN uses radio waves to connect devices in a local area network without wires. It uses access points to bridge wireless traffic to a wired backbone network. Wireless LANs use standards like 802.11 and connect devices in a basic service set through an access point, or extend coverage through multiple access points in an extended service set. They operate at the data link layer using CSMA/CA for media access and can provide optional security measures for authentication and privacy.
1.2 Wireless Local Area Netw BASICS.pptx
This document provides an overview of wireless local area networks (WLANs), including:
- An outline of topics such as wireless technology, IEEE 802.11 standards, securing WLANs, and migrating to wireless networks.
- Descriptions of how WLANs work and integrate with existing wired networks using access points, allowing users to roam between coverage areas while maintaining a continuous connection.
- Details on the 802.11 standards including 802.11a, 802.11b, 802.11g, security features, and comparisons of their data rates and frequencies.
Wc nots final unit new 8
This document provides an overview of wireless communication standards including IEEE 802.11x, 802.15x, and 802.16x. It discusses the objectives of the unit which are to explain the differences between wireless LANs, PANs, and MANs. It then goes on to describe the evolution of IEEE 802.11 standards including improvements to data rates, security, and quality of service over time. Key standards such as 802.11a, 802.11b, 802.11g, and 802.11n are explained. Design challenges for wireless LANs like changing topologies and interference are also summarized.
Networking Basics
Explains the history as well as basic concepts of computer networks, including the OSI model, IP protocol and Internetworking.
Wlan IEEE 802.11
A wireless local area network (WLAN) uses radio waves to wirelessly connect devices within a local area like a home or office, often including an access point to connect to the internet. WLANs use specialized protocols at the physical and data link layers and integrate into existing networks through access points. Common WLAN standards include IEEE 802.11b, 802.11a, and 802.11g which provide speeds up to 11Mbps, 54Mbps, and 54Mbps respectively in the 2.4GHz and 5GHz bands. Real-time services like voice can be transported over WLANs using protocols like PCF but may require echo cancellation to meet latency requirements.
5 IEEE standards
The IEEE 802 is a family of IEEE standards dealing with Local Area Networks and Metropolitan Area Networks. The IEEE 802 family of standards is maintained by the IEEE 802 LAN/MAN Standards Committee (LMSC).
The most widely used standards are for the Bridging and Virtual Bridged LANs (802.1), Ethernet family (802.3), Token Ring (802.5) and Wireless LAN (802.11).
Wi fi fundamentals
Wi-Fi is a wireless networking technology that uses radio waves to enable wireless local area networking with devices. It uses the IEEE 802.11 standards and was introduced in 1998. The document discusses the evolution of Wi-Fi standards from 802.11 to 802.11ac, explaining key features such as OFDM, MIMO, and MU-MIMO that have increased data rates and throughput over time. The latest standards discussed are 802.11ac, which supports speeds up to 3.5Gbps using 256-QAM and 802.11ad which operates at 60GHz and supports speeds up to 7.2Gbps.
Ieee 802.11 wireless lan
The document discusses wireless local area networks (WLANs) and the IEEE 802.11 standard. It provides an overview of wired and wireless LANs, the development and specifications of IEEE 802.11, and differences between wireless and wired networks that 802.11 addresses like power management, security, and bandwidth. It also covers wireless LAN topologies, media access control, security issues, and physical layer standards defined in original 802.11 like frequency hopping spread spectrum and direct sequence spread spectrum.
Cisco WLAN - Chapter. 02 : Part 1 – 802.11 MAC and Cisco Client Adapters
Cisco Fundamentals of Wireless LANs
Ch. 02 – Part 1 – 802.11 MAC and Cisco Client Adapters
Yaser Rahmati | یاسر رحمتی
Rahmati Academy | آکادمی رحمتی
www.yaser-rahmati.ir
www.rahmati-academy.ir
Lecture 14
The document discusses several aspects of wireless local area networks (WLANs) including:
1. IEEE 802.11b is an enhancement of the original 802.11 standard that achieved data rates up to 11 Mbps using modifications to the physical layer.
2. IEEE 802.11a operates in the 5GHz band and supports data rates up to 54 Mbps using orthogonal frequency-division multiplexing (OFDM).
3. Many future developments are planned including enhancements to security, quality of service, and higher data rates above 100 Mbps.
80211
The document discusses IEEE 802.11 wireless LAN standards. It covers the physical layer specifications of 802.11b using HR/DSSS and 802.11a using OFDM. It also describes the MAC layer functions including CSMA/CA, fragmentation, power management, and quality of service enhancements. Security methods like WEP and 802.1x are summarized. Key concepts discussed are the BSS, ESS network architecture, and differences from Ethernet in medium access.
NET1.PPT
Ethernet and Fast Ethernet standards define the physical implementation of local area networks using twisted pair cable and fiber optics. Ethernet uses CSMA/CD access method over coaxial cable or twisted pair up to 100 meters, while Fast Ethernet operates at 100 Mbps over twisted pair or fiber. Repeaters can extend the length of an Ethernet segment by regenerating the signal past the maximum segment distance.
IEEE 802.16e / Mobile Wimax
The document discusses the IEEE 802.16e/Mobile WiMAX standard. It provides an overview of 802.16, noting it specifies broadband wireless connectivity for metropolitan networks. 802.16e adds mobility support for speeds up to 75 mph. The physical layer uses OFDMA and has data rates up to 30 Mbps for 1-3 mile ranges. The MAC layer provides QoS using service flows and supports handoff methods like hard and fast handoffs.
computer network
- Wireless LAN (WLAN) uses radio waves to connect devices in a local area without wires. It allows mobility within the network coverage area while maintaining an internet connection.
- Benefits of WLAN include easier installation, scalability, and reduced costs compared to wired networks. Drawbacks include greater susceptibility to interference and lower speeds.
- Key applications of WLAN include extending a wired LAN, connecting nearby buildings, providing mobile access on campuses, and temporary ad hoc networks.
IT8602 Mobile Communication - Unit III
The document provides information about wireless networks and standards including IEEE 802.11 (Wi-Fi), Bluetooth, and WiMAX. It discusses the goals and architecture of wireless LANs and PANs, as well as standards like IEEE 802.11, Bluetooth, and their protocols. Key topics covered include the IEEE 802.11 standard including physical layer specifications and MAC architecture, Bluetooth architecture and piconet/scatternet topologies, and protocols in the Bluetooth and IEEE 802.11 stacks.
Wlan 1 intro
This document provides an overview of wireless local area networks (WLANs), including:
- The advantages and disadvantages of WLANs compared to wired networks.
- A comparison of infrared and radio transmission methods.
- A comparison of infrastructure and ad-hoc network architectures.
- An overview of the IEEE 802.11 standard including physical layer specifications and the distributed coordination function (DCF) medium access control protocol.
Wireless Networks-ASH-NEW
The document outlines a presentation on wireless technology and migrating to wireless LANs. It discusses key topics such as the IEEE 802.11 standards, securing wireless LANs, and considerations for cutting the cord to wired networks. An overview of wireless LAN technologies like 802.11a, 802.11b, 802.11g is provided along with their advantages and disadvantages. The presentation also covers wireless LAN fundamentals, security issues, and best practices for planning a wireless network migration through access point placement and site surveys.
Wireless networksppt
The document discusses wireless local area networks (WLANs) and the IEEE 802.11 standards. It provides an overview of wireless technology, outlines the 802.11 standards including 802.11a, 802.11b, 802.11g, security features, and challenges. It also summarizes how WLANs integrate with existing networks through access points and allow roaming between coverage areas.
Wireless networksppt
The document discusses wireless local area networks (WLANs) and the IEEE 802.11 standards. It provides an overview of wireless technology, outlines the 802.11 standards including 802.11a, 802.11b, 802.11g, security features, and challenges. It also summarizes how WLANs integrate with existing networks through access points and allow roaming between coverage areas.
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Cisco WLAN - Chapter. 02 : Part 1 – 802.11 MAC and Cisco Client Adapters
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Wlan 802.11n - MAC Sublayer
- 1. MAC Sublayer in WLAN 802.11n 1 Presented by Syed Ahamad Abhishek Raj CS252 – Computer Network
- 2. Outline Introduction Architecture Physical layer MAC Sublayer Conclusion 2
- 3. References Wikipedia Text book – Tanenbaum 3
- 4. Introduction WLAN – most popular for mobile equipment’s Interoperability Mobility Flexibility cost-effective deployment Standardize and maintain as IEEE 802.11 by IEEE LAN/MAN Standards Committee(IEEE 802) Established in 1997 802.11a/b/g 802.11n 4
- 5. Architecture components Stations Basic Service set Extended Service set DS (Distribution System) 5
- 6. WLAN Architecture 6 • Infrastructure • Ad hoc
- 7. Factor - 802.11n Limited Capacity Channel Efficiency Multipath 7
- 10. Multipath 10
- 11. Key Structure – 802.11n 11
- 12. RF Signal Fidelity Parallel Streams Multiple antennas Identification of each frame Echo cancellation Timer setting Much reduce frame duplication Transmission beam forming When receiver is busy – sender finds the best way to transmit. High quality of signal 12
- 13. Physical layer Rate adaptation 802.11b(11Mbps) – spread spectrum method Spreading sequence – Barker Sequence 802.11a(54Mbps) – OFDM method But 5 GHz 802.11g(54Mbps) – OFDM method Here 2.4 GHz 13
- 14. Physical layer 802.11n(100+Mbps) – OFDM and MIMO method Bandwidth - 20MHz to 40MHz Reduced the framing overhead Parallel streams 14
- 15. 15Protocol Stack
- 16. MAC Sublayer protocol efficiency WMM Mandatory WMM – allows AP to control devices Assures the quality of service standards 802.11 – CSMA/CA protocol Minimum contention overhead Selective retransmission 16
- 17. 802.11 MAC Protocol 17
- 18. 802.11n MAC Protocol 18 • Mode operation • DCF(Distributed Coordination Function) • PCF(Point Coordination Function)
- 19. Hidden and Exposed problem Transmission Range Solution – Physical and virtual sensing. 19
- 22. Frame format 22
- 23. Conclusion Limitation Spiky and time variant Transmission Range Power saving – beacon frames Trade off 23