CSE 4215/5431: Mobile Communications Winter Suprakash Datta
|
|
|
- Andrea Short
- 7 years ago
- Views:
Transcription
1 CSE 4215/5431: Mobile Communications Winter 2013 Suprakash Datta Office: CSEB 3043 Phone: ext Course page: Some slides are adapted from the Schiller book slides 2/26/2013 CSE 4215/5431, Winter
2 Next: Wireless LANs Direct application/case studies for the MAC algorithms discussed 2/26/2013 CSE 4215/5431, Winter
3 Mobile Communication Technology Local wireless networks WLAN according to IEEE WiFi a b h i/e/ /n/ /z/aa g Personal area wireless nw WPAN ZigBee Bluetooth Wireless distribution networks WMAN (Broadband Wireless Access) a/b/c/d/e/f/g ,.6 (WBAN) WiMAX + Mobility [ (Mobile Broadband Wireless Access)] e (addition to.16 for mobile devices) b/c 2/26/2013 CSE 4215/5431, Winter
4 Characteristics of wireless LANs Advantages very flexible within the reception area Ad-hoc networks without previous planning possible (almost) no wiring difficulties (e.g. historic buildings, firewalls) more robust against disasters like, e.g., earthquakes, fire - or users pulling a plug... Disadvantages typically very low bandwidth compared to wired networks (1-10 Mbit/s) due to shared medium many proprietary solutions, especially for higher bit-rates, standards take their time (e.g. IEEE n) products have to follow many national restrictions 2/26/2013 CSE 4215/5431, Winter
5 Design goals for wireless LANs global, seamless operation low power for battery use no special permissions or licenses needed to use the LAN robust transmission technology simplified spontaneous cooperation at meetings easy to use for everyone, simple management protection of investment in wired networks security (no one should be able to read my data), privacy (no one should be able to collect user profiles), safety (low radiation) transparency concerning applications and higher layer protocols, but also location awareness if necessary 2/26/2013 CSE 4215/5431, Winter
6 Comparison: infrared vs. radio transmission Infrared uses IR diodes, diffuse light, multiple reflections (walls, furniture etc.) Advantages simple, cheap, available in many mobile devices no licenses needed simple shielding possible Disadvantages interference by sunlight, heat sources etc. many things shield or absorb IR light low bandwidth Example IrDA (Infrared Data Association) interface available everywhere Radio typically using the license free ISM band at 2.4 GHz Advantages experience from wireless WAN and mobile phones can be used coverage of larger areas possible (radio can penetrate walls, furniture etc.) Disadvantages very limited license free frequency bands shielding more difficult, interference with other electrical devices Example Many different products 2/26/2013 CSE 4215/5431, Winter
7 infrastructure network Comparison: infrastructure vs. adhoc networks AP AP wired network AP: Access Point AP ad-hoc network 2/26/2013 CSE 4215/5431, Winter
8 STA 1 ESS Architecture of an LAN BSS 1 Access Point BSS 2 infrastructure network Portal Distribution System Access Point 802.x LAN STA LAN STA 3 Station (STA) terminal with access mechanisms to the wireless medium and radio contact to the access point Basic Service Set (BSS) group of stations using the same radio frequency Access Point station integrated into the wireless LAN and the distribution system Portal : bridge to other (wired) networks Distribution System interconnection network to form one logical network (EES: Extended Service Set) based on several BSS 2/26/2013 CSE 4215/5431, Winter
9 STA Architecture of an ad-hoc LAN IBSS 1 STA 2 STA 4 IBSS 2 STA LAN network STA 5 Direct communication within a limited range Station (STA): terminal with access mechanisms to the wireless medium Independent Basic Service Set (IBSS): group of stations using the same radio frequency 2/26/2013 CSE 4215/5431, Winter
10 IEEE standard mobile terminal fixed terminal application TCP IP LLC access point LLC infrastructure network application TCP IP LLC MAC MAC MAC MAC PHY PHY PHY PHY 2/26/2013 CSE 4215/5431, Winter
11 Layers and functions PHY DLC MAC access mechanisms, fragmentation, encryption MAC Management synchronization, roaming, MIB, power management LLC MAC PLCP PMD MAC Management PHY Management PLCP Physical Layer Convergence Protocol clear channel assessment signal (carrier sense) PMD Physical Medium Dependent modulation, coding PHY Management channel selection, MIB Station Management coordination of all management functions Station Management 2/26/2013 CSE 4215/5431, Winter
12 Physical layer (legacy) 3 versions: 2 radio (typ. 2.4 GHz), 1 IR data rates 1 or 2 Mbit/s FHSS (Frequency Hopping Spread Spectrum) spreading, despreading, signal strength, typ. 1 Mbit/s min. 2.5 frequency hops/s (USA), two-level GFSK modulation DSSS (Direct Sequence Spread Spectrum) DBPSK modulation for 1 Mbit/s (Differential Binary Phase Shift Keying), DQPSK for 2 Mbit/s (Differential Quadrature PSK) preamble and header of a frame is always transmitted with 1 Mbit/s, rest of transmission 1 or 2 Mbit/s chipping sequence: +1, -1, +1, +1, -1, +1, +1, +1, -1, -1, -1 (Barker code) max. radiated power 1 W (USA), 100 mw (EU), min. 1mW Infrared nm, diffuse light, typ. 10 m range carrier detection, energy detection, synchronization 2/26/2013 CSE 4215/5431, Winter
13 FHSS PHY packet format (legacy) Synchronization synch with Pattern (80 bits) SFD (Start Frame Delimiter) 16 bits start pattern PLW (PLCP_PDU Length Word) length of payload incl. 32 bit CRC of payload, PLW < 4096 PSF (PLCP Signaling Field) data of payload (1 or 2 Mbit/s) HEC (Header Error Check) CRC with x 16 +x 12 +x variable bits synchronization SFD PLW PSF HEC payload PLCP preamble PLCP header 2/26/2013 CSE 4215/5431, Winter
14 DSSS PHY packet format (legacy) Synchronization synch., gain setting, energy detection, frequency offset compensation SFD (Start Frame Delimiter) Signal data rate of the payload (0A: 1 Mbit/s DBPSK; 14: 2 Mbit/s DQPSK) Service future use, 00: compliant Length length of the payload HEC (Header Error Check) protection of signal, service and length, x 16 +x 12 +x variable bits synchronization SFD signal service length HEC payload PLCP preamble PLCP header 2/26/2013 CSE 4215/5431, Winter
15 MAC layer I - DFWMAC Traffic services Asynchronous Data Service (mandatory) exchange of data packets based on best-effort support of broadcast and multicast Time-Bounded Service (optional) implemented using PCF (Point Coordination Function) Access methods DFWMAC-DCF CSMA/CA (mandatory) collision avoidance via randomized back-off mechanism minimum distance between consecutive packets ACK packet for acknowledgements (not for broadcasts) DFWMAC-DCF w/ RTS/CTS (optional) Distributed Foundation Wireless MAC avoids hidden terminal problem DFWMAC- PCF (optional) access point polls terminals according to a list 2/26/2013 CSE 4215/5431, Winter
16 MAC layer II Priorities defined through different inter frame spaces no guaranteed, hard priorities (Short Inter Frame Spacing) highest priority, for ACK, CTS, polling response PIFS (PCF IFS) medium priority, for time-bounded service using PCF DIFS (DCF, Distributed Coordination Function IFS) lowest priority, for asynchronous data service DIFS medium busy DIFS PIFS direct access if medium is free DIFS contention next frame 2/26/2013 CSE 4215/5431, Winter t
17 CSMA/CA access method I station ready to send starts sensing the medium (Carrier Sense based on CCA, Clear Channel Assessment) if the medium is free for the duration of an Inter-Frame Space (IFS), the station can start sending (IFS depends on service type) if the medium is busy, the station has to wait for a free IFS, then the station must additionally wait a random back-off time (collision avoidance, multiple of slot-time) if another station occupies the medium during the back-off time of the station, the back-off timer stops (fairness) DIFS medium busy DIFS contention window (randomized back-off mechanism) next frame direct access if medium is free DIFS slot time (20µs) 2/26/2013 CSE 4215/5431, Winter t
18 competing stations - simple version DIFS DIFS bo e bo r DIFS bo e bo r DIFS bo e busy station 1 bo e busy station 2 station 3 busy bo e busy bo e bo r station 4 bo e bo r bo e busy bo e bo r station 5 t busy medium not idle (frame, ack etc.) bo e elapsed backoff time packet arrival at MAC bo r residual backoff time 2/26/2013 CSE 4215/5431, Winter
19 CSMA/CA access method II Sending unicast packets station has to wait for DIFS before sending data receivers acknowledge at once (after waiting for ) if the packet was received correctly (CRC) automatic retransmission of data packets in case of transmission errors sender receiver other stations DIFS data waiting time ACK DIFS contention data t 2/26/2013 CSE 4215/5431, Winter
20 DFWMAC Sending unicast packets station can send RTS with reservation parameter after waiting for DIFS (reservation determines amount of time the data packet needs the medium) acknowledgement via CTS after by receiver (if ready to receive) sender can now send data at once, acknowledgement via ACK other stations store medium reservations distributed via RTS sender receiver and CTS DIFS RTS CTS data ACK other stations NAV (RTS) NAV (CTS) defer access DIFS contention data 2/26/2013 CSE 4215/5431, Winter t
21 Fragmentation sender receiver DIFS RTS CTS frag 1 ACK 1 frag 2 ACK2 other stations NAV (RTS) NAV (CTS) NAV (frag 1 ) NAV (ACK 1 ) DIFS contention data t 2/26/2013 CSE 4215/5431, Winter
22 DFWMAC-PCF I (almost never used) t 0 t 1 SuperFrame medium busy point coordinator PIFS D 1 D 2 wireless stations U 1 U 2 stations NAV NAV 2/26/2013 CSE 4215/5431, Winter
23 DFWMAC-PCF II t 2 t 3 t 4 PIFS CFend point coordinator D 3 D 4 wireless stations U 4 stations NAV NAV contention free period contention period t 2/26/2013 CSE 4215/5431, Winter
24 bytes Types Frame format control frames, management frames, data frames Sequence numbers important against duplicated frames due to lost ACKs Addresses receiver, transmitter (physical), BSS identifier, sender (logical) Miscellaneous Frame Control sending time, checksum, frame control, data Duration/ ID Address 1 Address 2 Address 3 Sequence Control Protocol version 1 To Type Subtype DS More Frag Power Retry Mgmt Address Data 4 bits From DS More Data WEP Order 2/26/2013 CSE 4215/5431, Winter CRC
25 Special Frames: ACK, RTS, CTS Acknowledgement ACK bytes Frame Duration Receiver CRC Control Address Request To Send RTS bytes Frame Duration Receiver Transmitter CRC Control Address Address Clear To Send CTS bytes Frame Duration Receiver CRC Control Address 2/26/2013 CSE 4215/5431, Winter
26 MAC management Synchronization try to find a LAN, try to stay within a LAN Clock synchronization Power management sleep-mode without missing a message periodic sleep, frame buffering, traffic measurements Association/Reassociation integration into a LAN roaming, i.e. change networks by changing access points scanning, i.e. active search for a network MIB - Management Information Base managing, read, write Accessible through SNMP 2/26/2013 CSE 4215/5431, Winter
27 Synchronization TSF: timing synchronization function Needed for polling, frequency hopping Use of beacons for timestamps, other information Not periodic not sent when medium is busy Who transmits beacons in ad hoc mode? 2/26/2013 CSE 4215/5431, Winter
28 Synchronization using a Beacon (infrastructure) beacon interval (20ms 1s) access point medium B B B B busy busy busy busy value of the timestamp B beacon frame t 2/26/2013 CSE 4215/5431, Winter
29 Synchronization using a Beacon (ad-hoc) beacon interval station 1 B 1 B 1 station 2 B 2 B 2 medium busy busy busy busy t value of the timestamp B beacon frame random delay 2/26/2013 CSE 4215/5431, Winter
30 Security issues? Can a malicious node provide incorrect timing information? 2/26/2013 CSE 4215/5431, Winter
802.11 standard. Acknowledgement: Slides borrowed from Richard Y. Yang @ Yale
802.11 standard Acknowledgement: Slides borrowed from Richard Y. Yang @ Yale IEEE 802.11 Requirements Design for small coverage (e.g. office, home) Low/no mobility High data-rate applications Ability to
Wiereless LAN 802.11
Tomasz Kurzawa Wiereless LAN 802.11 Introduction The 802.11 Architecture Channels and Associations The 802.11 MAC Protocol The 802.11 Frame Introduction Wireless LANs are most important access networks
Wireless LAN advantages. Wireless LAN. Wireless LAN disadvantages. Wireless LAN disadvantages WLAN:
WLAN: Wireless LAN Make use of a wireless transmission medium Tipically restricted in their diameter: buildings, campus, single room etc.. The global goal is to replace office cabling and to introduce
CSMA/CA. Information Networks p. 1
Information Networks p. 1 CSMA/CA IEEE 802.11 standard for WLAN defines a distributed coordination function (DCF) for sharing access to the medium based on the CSMA/CA protocol Collision detection is not
Chapter 7 Low-Speed Wireless Local Area Networks
Wireless# Guide to Wireless Communications 7-1 Chapter 7 Low-Speed Wireless Local Area Networks At a Glance Instructor s Manual Table of Contents Overview Objectives s Quick Quizzes Class Discussion Topics
IEEE 802.11 Technical Tutorial. Introduction. IEEE 802.11 Architecture
IEEE 802.11 Technical Tutorial Introduction The purpose of this document is to give technical readers a basic overview of the new 802.11 Standard, enabling them to understand the basic concepts, principle
Lecture 17: 802.11 Wireless Networking"
Lecture 17: 802.11 Wireless Networking" CSE 222A: Computer Communication Networks Alex C. Snoeren Thanks: Lili Qiu, Nitin Vaidya Lecture 17 Overview" Project discussion Intro to 802.11 WiFi Jigsaw discussion
IEEE802.11 Wireless LAN
IEEE802.11 The broadband wireless Internet Maximilian Riegel wlan-tutorial.ppt-1 (28.11.2000) WLAN Dream Finally Seems to Happen... Recently lots of serious WLAN activities have been announced Big players
WiFi. Is for Wireless Fidelity Or IEEE 802.11 Standard By Greg Goldman. WiFi 1
WiFi Is for Wireless Fidelity Or IEEE 802.11 Standard By Greg Goldman WiFi 1 What is the goal of 802.11 standard? To develop a Medium Access Control (MAC) and Physical Layer (PHY) specification for wireless
Introduction to Ad hoc Networks
Introduction to Ad hoc Networks CS-647: Advanced Topics in Wireless Networks Drs. Baruch Awerbuch & Amitabh Mishra Department of Computer Science Johns Hopkins University Amitabh Mishra & Baruch Awerbuch
A Technical Tutorial on the IEEE 802.11 Protocol
A Technical Tutorial on the IEEE 802.11 Protocol By Pablo Brenner Director of Engineering copyright BreezeCOM 1997 Introduction The purpose of this document is to give technical readers a basic overview
Medium Access Control (MAC) Protocols for Ad hoc Wireless Networks - III
Medium Access Control (MAC) Protocols for Ad hoc Wireless Networks - III CS: 647 Advanced Topics in Wireless Networks Drs. Baruch Awerbuch & Amitabh Mishra Department of Computer Science Johns Hopkins
802.11 Wireless LAN Protocol CS 571 Fall 2006. 2006 Kenneth L. Calvert All rights reserved
802.11 Wireless LAN Protocol CS 571 Fall 2006 2006 Kenneth L. Calvert All rights reserved Wireless Channel Considerations Stations may move Changing propagation delays, signal strengths, etc. "Non-transitive"
Basic processes in IEEE802.11 networks
Module contents IEEE 802.11 Terminology IEEE 802.11 MAC Frames Basic processes in IEEE802.11 networks Configuration parameters.11 Architect. 1 IEEE 802.11 Terminology Station (STA) Architecture: Device
IEEE 802 Protocol Layers. IEEE 802.11 Wireless LAN Standard. Protocol Architecture. Protocol Architecture. Separation of LLC and MAC.
IEEE 802.11 Wireless LAN Standard IEEE 802 Protocol Layers Chapter 14 Protocol Architecture Functions of physical layer: Encoding/decoding of signals Preamble generation/removal (for synchronization) Bit
Medium Access Control (MAC) and Wireless LANs
Medium Access Control (MAC) and Wireless LANs Outline Wireless LAN Technology Medium Access Control for Wireless IEEE 802.11 Wireless LAN Applications LAN Extension Cross-building interconnect Nomadic
802.11. Markku Renfors. Partly based on student presentation by: Lukasz Kondrad Tomasz Augustynowicz Jaroslaw Lacki Jakub Jakubiak
802.11 Markku Renfors Partly based on student presentation by: Lukasz Kondrad Tomasz Augustynowicz Jaroslaw Lacki Jakub Jakubiak Contents 802.11 Overview & Architecture 802.11 MAC 802.11 Overview and Architecture
CSE331: Introduction to Networks and Security. Lecture 6 Fall 2006
CSE331: Introduction to Networks and Security Lecture 6 Fall 2006 Open Systems Interconnection (OSI) End Host Application Reference model not actual implementation. Transmits messages (e.g. FTP or HTTP)
IEEE 802.11 WLAN (802.11) ...Copyright. Renato Lo Cigno www.disi.unitn.it/locigno/didattica/nc/
WLAN (802.11) Renato Lo Cigno www.disi.unitn.it/locigno/didattica/nc/...copyright Quest opera è protetta dalla licenza Creative Commons NoDerivs-NonCommercial. Per vedere una copia di questa licenza, consultare:
IEEE 802.11 Wireless LAN Standard. Updated: 5/10/2011
IEEE 802.11 Wireless LAN Standard Updated: 5/10/2011 IEEE 802.11 History and Enhancements o 802.11 is dedicated to WLAN o The group started in 1990 o First standard that received industry support was 802.11b
... neither PCF nor CA used in practice
IEEE 802.11 MAC CSMA/CA with exponential backoff almost like CSMA/CD drop CD CSMA with explicit ACK frame added optional feature: CA (collision avoidance) Two modes for MAC operation: Distributed coordination
Overview of 802.11 Networks and Standards
Overview of 802.11 Networks and Standards Mauri Kangas, Helsinki University of Technology, 17.02.2004 Mauri Kangas 17.2.2004 Page 1 (34) Family of 802.xx Standards ISO/IEC 8802-xx = IEEE 802.xx IEEE 802.1
Attenuation (amplitude of the wave loses strength thereby the signal power) Refraction Reflection Shadowing Scattering Diffraction
Wireless Physical Layer Q1. Is it possible to transmit a digital signal, e.g., coded as square wave as used inside a computer, using radio transmission without any loss? Why? It is not possible to transmit
Wireless Personal Area Networks (WPANs)
Wireless Personal Area Networks (WPANs) Bluetooth, ZigBee Contents Introduction to the IEEE 802 specification family Concept of ISM frequency band Comparison between different wireless technologies ( and
Wireless Local Area Networks and the 802.11 Standard
Wireless Local Area Networks and the 802.11 Standard March 31, 2001 Plamen Nedeltchev, PhD Edited by Felicia Brych Table of Contents1 Introduction... 3 Upper Layer Protocols of OSI... 3 WLAN Architecture...
IEEE 802.11 frame format
IEEE 802.11 frame format Pietro Nicoletti www.studioreti.it 802-11-Frame - 1 P. Nicoletti: see note pag. 2 Copyright note These slides are protected by copyright and international treaties. The title and
Communication Networks 629. IEEE 802.11 Standards and Developments
Communication Networks IEEE 802.11 Standards and Developments Prof. Jochen Seitz Overview Organization of a WLAN according to IEEE 802.11 Current IEEE 802.11 standards IEEE 802.11 layers IEEE 802.11 MAC
A Short Look on Power Saving Mechanisms in the Wireless LAN Standard Draft IEEE 802.11
A Short Look on Power Saving Mechanisms in the Wireless LAN Standard Draft IEEE 802.11 Christian Röhl, Hagen Woesner, Adam Wolisz * Technical University Berlin Telecommunication Networks Group {roehl,
CS6956: Wireless and Mobile Networks Lecture Notes: 2/11/2015. IEEE 802.11 Wireless Local Area Networks (WLANs)
CS6956: Wireless and Mobile Networks Lecture Notes: //05 IEEE 80. Wireless Local Area Networks (WLANs) CSMA/CD Carrier Sense Multi Access/Collision Detection detects collision and retransmits, no acknowledgement,
EPL 657 Wireless Networks
EPL 657 Wireless Networks Some fundamentals: Multiplexing / Multiple Access / Duplex Infrastructure vs Infrastructureless Panayiotis Kolios Recall: The big picture... Modulations: some basics 2 Multiplexing
ECE 358: Computer Networks. Homework #3. Chapter 5 and 6 Review Questions 1
ECE 358: Computer Networks Homework #3 Chapter 5 and 6 Review Questions 1 Chapter 5: The Link Layer P26. Let's consider the operation of a learning switch in the context of a network in which 6 nodes labeled
IEEE 802.11e WLANs / WMM. S.Rajesh (rajeshsweb@gmail.com) AU-KBC Research Centre, BroVis Wireless Networks, smartbridges Pte Ltd.
IEEE 802.11e WLANs / WMM S.Rajesh (rajeshsweb@gmail.com) AU-KBC Research Centre, BroVis Wireless Networks, smartbridges Pte Ltd. Outline A short review of 802.11 MAC Drawbacks of 802.11 MAC Application
WI-FI TECHNOLOGY: SECURITY ISSUES
RIVIER ACADEMIC JOURNAL, VOLUME 2, NUMBER 2, FALL 2006 WI-FI TECHNOLOGY: SECURITY ISSUES Vandana Wekhande* Graduate student, M.S. in Computer Science Program, Rivier College Keywords: Wireless Internet,802.11b,
Adaptive DCF of MAC for VoIP services using IEEE 802.11 networks
Adaptive DCF of MAC for VoIP services using IEEE 802.11 networks 1 Mr. Praveen S Patil, 2 Mr. Rabinarayan Panda, 3 Mr. Sunil Kumar R D 1,2,3 Asst. Professor, Department of MCA, The Oxford College of Engineering,
An Overview of Wireless LAN Standards IEEE 802.11 and IEEE 802.11e
An Overview of Wireless LAN Standards IEEE 802.11 and IEEE 802.11e Jahanzeb Farooq, Bilal Rauf Department of Computing Science Umeå University Sweden Jahanzeb Farooq, 2006 (tipputhegreat@hotmail.com) Chapter
The IEEE 802.11 standard
The IEEE 802.11 standard Imad Aad INRIA, Planete team IN Tech, May 31st, 2002 IEEE 802.11 p.1 Outline WLANs vs. Wired LANs History Working modes MAC sub-layer The PHY layer (1997) The PHY Extensions (1999)
Networks. Master of Science (Computer Science and Engineering), December 2004, 45 pp.,
Park, Sangtae, Optimal Access Point Selection and Channel Assignment in IEEE 802.11 Networks. Master of Science (Computer Science and Engineering), December 2004, 45 pp., 9 tables, 17 figures, 29 titles.
Introduction to IEEE 802.11 Wireless LAN
Introduction to IEEE 802.11 Wireless LAN Li-Hsing Yen Chung Hua University Fall 2006 Difference Between Wired and Wireless LANs The medium impacts the design stations are mobile different MAC 1 Medium
TCP in Wireless Networks
Outline Lecture 10 TCP Performance and QoS in Wireless s TCP Performance in wireless networks TCP performance in asymmetric networks WAP Kurose-Ross: Chapter 3, 6.8 On-line: TCP over Wireless Systems Problems
Lab Exercise 802.11. Objective. Requirements. Step 1: Fetch a Trace
Lab Exercise 802.11 Objective To explore the physical layer, link layer, and management functions of 802.11. It is widely used to wireless connect mobile devices to the Internet, and covered in 4.4 of
LAN Switching. 15-441 Computer Networking. Switched Network Advantages. Hubs (more) Hubs. Bridges/Switches, 802.11, PPP. Interconnecting LANs
LAN Switching 15-441 Computer Networking Bridges/Switches, 802.11, PPP Extend reach of a single shared medium Connect two or more segments by copying data frames between them Switches only copy data when
Protocolo IEEE 802.15.4. Sergio Scaglia SASE 2012 - Agosto 2012
Protocolo IEEE 802.15.4 SASE 2012 - Agosto 2012 IEEE 802.15.4 standard Agenda Physical Layer for Wireless Overview MAC Layer for Wireless - Overview IEEE 802.15.4 Protocol Overview Hardware implementation
Frequency Hopping Spread Spectrum PHY of the 802.11 Wireless LAN Standard. Why Frequency Hopping?
Frequency Hopping Spread Spectrum PHY of the 802.11 Wireless LAN Standard Presentation to IEEE 802 March 11, 1996 Naftali Chayat BreezeCom 1 Why Frequency Hopping? Frequency Hopping is one of the variants
How To Understand The Power Of A Network On A Microsoft Ipa 2.5 (Ipa) 2.2.2 (Ipam) 2-2.5-2 (Networking) 2 (Ipom) 2(2
Workshop Presentation Chapter4 Yosuke TANAKA Agenda(Framing in Detail) Data Frames Control Frames type RTS Duration CTS Addressing (!!important!!) Variation on Data Frame Theme Applied Data Framing ACK
Wireless Networks. Reading: Sec5on 2.8. COS 461: Computer Networks Spring 2011. Mike Freedman
1 Wireless Networks Reading: Sec5on 2.8 COS 461: Computer Networks Spring 2011 Mike Freedman hep://www.cs.princeton.edu/courses/archive/spring11/cos461/ 2 Widespread Deployment Worldwide cellular subscribers
LP-348. LP-Yagy2415. LP-510G/550G 54M Wireless Adapter PCMCIA/PCI. User Guide Ver:2.0 LP-5420G WWW.LANPRO.COM
LP-348 LP-Yagy2415 LP-1518 LP-5P LP-510G/550G 54M Wireless Adapter PCMCIA/PCI User Guide Ver:2.0 LP-5420G WWW.LANPRO.COM COPYRIGHT & TRADEMARKS Specifications are subject to change without notice. is a
WPAN. Contents. S-72.3240 Wireless Personal, Local, Metropolitan, and Wide Area Networks 1
Contents Bluetooth (IEEE 802.15.1) Network topology FHSS operation Link delivery services System architecture & protocols Usage models ZigBee (IEEE 802.15.4) Network topology Physical layer operation CSMA/CA
IEEE 802.11 Wireless Local Area Networks
ABSTRACT The draft IEEE 82. Wireless Local Area Network (WLAN) specification is approaching completion. In this article, the IEEE 82. protocol is explained, with particular emphasis on the medium access
EECS 122: Introduction to Computer Networks Multiaccess Protocols. ISO OSI Reference Model for Layers
EECS 122: Introduction to Computer Networks Multiaccess Protocols Computer Science Division Department of Electrical Engineering and Computer Sciences University of California, Berkeley Berkeley, CA 94720-1776
An Investigation of the Impact of Signal Strength on Wi-Fi Link Throughput through Propagation Measurement. Eric Cheng-Chung LO
An Investigation of the Impact of Signal Strength on Wi-Fi Link Throughput through Propagation Measurement Eric Cheng-Chung LO A dissertation submitted to Auckland University of Technology in partial fulfillment
Mustafa Ergen June 2002 ergen@eecs.berkeley.edu. Department of Electrical Engineering and Computer Science University of California Berkeley
Mustafa Ergen June 2002 ergen@eecs.berkeley.edu Department of Electrical Engineering and Computer Science University of California Berkeley 2 Abstract This document describes IEEE 802.11 Wireless Local
10. Wireless Networks
Computernetzwerke und Sicherheit (CS221) 10. Wireless Networks 1. April 2011 omas Meyer Departement Mathematik und Informatik, Universität Basel Chapter 6 Wireless and Mobile Networks (with changes CS221
Mobile Communications Exercise: Satellite Systems and Wireless LANs. Georg von Zengen, IBR, TU Braunschweig, www.ibr.cs.tu-bs.de
Mobile Communications Exercise: Satellite Systems and Wireless LANs N 1 Please define the terms inclination and elevation using the following two figures. How do these parameters influence the usefulness
Lecture 7 Multiple Access Protocols and Wireless
Lecture 7 Multiple Access Protocols and Wireless Networks and Security Jacob Aae Mikkelsen IMADA November 11, 2013 November 11, 2013 1 / 57 Lecture 6 Review What is the responsibility of the link layer?
ECE 428 Computer Networks and Security
ECE 428 Computer Networks and Security 1 Instructor: Sagar Naik About the Instructor Office: EIT 4174, ECE Dept. Other courses that I teach ECE 355: Software Engineering ECE 453/CS 447/ SE 465: Software
Wireless LAN Concepts
Wireless LAN Concepts Wireless LAN technology is becoming increasingly popular for a wide variety of applications. After evaluating the technology, most users are convinced of its reliability, satisfied
MAC Algorithms in Wireless Networks
Department of Computing Science Master Thesis MAC Algorithms in Wireless Networks Applications, Issues and Comparisons Shoaib Tariq Supervisor: Dr. Jerry Eriksson Examiner: Dr. Per Lindström Dedicated
How To Analyze The Security On An Ipa Wireless Sensor Network
Throughput Analysis of WEP Security in Ad Hoc Sensor Networks Mohammad Saleh and Iyad Al Khatib iitc Stockholm, Sweden {mohsaleh, iyad}@iitc.se ABSTRACT This paper presents a performance investigation
IEEE 802.11 WIRELESS LAN STANDARD
CHAPTER14 IEEE 802.11 WIRELESS LAN STANDARD 14.1 IEEE 802 Architecture Protocol Architecture MAC Frame Format Logical Link Control 14.2 IEEE 802.11 Architecture and Services IEEE 802.11 Architecture IEEE
TECHNICAL NOTE. GoFree WIFI-1 web interface settings. Revision Comment Author Date 0.0a First release James Zhang 10/09/2012
TECHNICAL NOTE GoFree WIFI-1 web interface settings Revision Comment Author Date 0.0a First release James Zhang 10/09/2012 1/14 Web interface settings under admin mode Figure 1: web interface admin log
Ethernet. Ethernet Frame Structure. Ethernet Frame Structure (more) Ethernet: uses CSMA/CD
Ethernet dominant LAN technology: cheap -- $20 for 100Mbs! first widely used LAN technology Simpler, cheaper than token rings and ATM Kept up with speed race: 10, 100, 1000 Mbps Metcalfe s Etheret sketch
Measuring the service level in the 2.4 GHz ISM band
Measuring the service level in the 2.4 GHz ISM band Internal report Jan-Willem van Bloem and Roel Schiphorst University of Twente Department of Electrical Engineering, Mathematics & Computer Science (EEMCS)
Performance Analysis of the IEEE 802.11 Wireless LAN Standard 1
Performance Analysis of the IEEE. Wireless LAN Standard C. Sweet Performance Analysis of the IEEE. Wireless LAN Standard Craig Sweet and Deepinder Sidhu Maryland Center for Telecommunications Research
CSE 123A Computer Networks
CSE 123A Computer Networks Winter 2005 Lecture 5: Data-Link II: Media Access Some portions courtesy Srini Seshan or David Wetherall Last Time Framing: How to translate a bitstream into separate packets
COMP 3331/9331: Computer Networks and Applications
COMP 3331/9331: Computer Networks and Applications Week 10 Wireless Networks Reading Guide: Chapter 6: 6.1 6.3 Wireless Networks + Security 1 Wireless and Mobile Networks Background: # wireless (mobile)
EETS 8316 Wireless Networks Fall 2013
EETS 8316 Wireless Networks Fall 2013 Lecture: WiFi Discovery, Powersave, and Beaconing http://lyle.smu.edu/~skangude/eets8316.html Shantanu Kangude skangude@lyle.smu.edu Discovery and Beaconing Discovery?
Ph.D. Thesis. Resources optimization in multimedia communications. Luca Sanna Randaccio. Advisor: Prof. Luigi Atzori
Ph.D. Thesis Resources optimization in multimedia communications Luca Sanna Randaccio Advisor: Prof. Luigi Atzori University of Cagliari Department of Electrical and Electronic Engineering Table of Contents
Local Area Networks transmission system private speedy and secure kilometres shared transmission medium hardware & software
Local Area What s a LAN? A transmission system, usually private owned, very speedy and secure, covering a geographical area in the range of kilometres, comprising a shared transmission medium and a set
Wireless Networking Technologies WLAN, WiFi Mesh and WiMAX
Wireless Networking Technologies WLAN, WiFi Mesh and WiMAX K R School of Information Technology sri@it.iitb.ac.in http://www.it.iitb.ac.in/~sri Course Outline Wireless Networks Difference from wired Mobility
Philippe Klein. avb-phkl-802-11-qos-overview-0811-1
802.11 QoS Overview Philippe Klein IEEE Plenary Meeting Nov 08 Dallas, TX avb-phkl-802-11-qos-overview-0811-1 Disclaimer This presentation is not a highly detailed technical presentation but a crash course
The Wireless Network Road Trip
The Wireless Network Road Trip The Association Process To begin, you need a network. This lecture uses the common logical topology seen in Figure 9-1. As you can see, multiple wireless clients are in
TL-WN310G 54M Wireless CardBus Adapter
54M Wireless CardBus Adapter Rev: 1.0.1 1910010042 COPYRIGHT & TRADEMARKS Specifications are subject to change without notice. is a registered trademark of TP-LINK TECHNOLOGIES CO., LTD. Other brands and
VoIP in 802.11. Mika Nupponen. S-72.333 Postgraduate Course in Radio Communications 06/04/2004 1
VoIP in 802.11 Mika Nupponen S-72.333 Postgraduate Course in Radio Communications 06/04/2004 1 Contents Introduction VoIP & WLAN Admission Control for VoIP Traffic in WLAN Voice services in IEEE 802.11
Collision of wireless signals. The MAC layer in wireless networks. Wireless MAC protocols classification. Evolutionary perspective of distributed MAC
The MAC layer in wireless networks The wireless MAC layer roles Access control to shared channel(s) Natural broadcast of wireless transmission Collision of signal: a /space problem Who transmits when?
ECE/CS 372 introduction to computer networks. Lecture 13
ECE/CS 372 introduction to computer networks Lecture 13 Announcements: HW #4 hard copy due today Lab #5 posted is due Tuesday June 4 th HW #5 posted is due Thursday June 6 th Pickup midterms Acknowledgement:
Frequency Hopping Spread Spectrum (FHSS) vs. Direct Sequence Spread Spectrum (DSSS) in Broadband Wireless Access (BWA) and Wireless LAN (WLAN)
FHSS vs. DSSS page 1 of 16 Frequency Hopping Spread Spectrum (FHSS) vs. Direct Sequence Spread Spectrum (DSSS) in Broadband Wireless Access (BWA) and Wireless LAN (WLAN) by Sorin M. SCHWARTZ Scope In 1997
Wireless Local Area Networking For Device Monitoring
Wireless Local Area Networking For Device Monitoring by Colin Goldsmith Supervised By Professor Wendi Heinzelman A thesis submitted in partial fulfillment of the Requirements for the Degree of Masters
Express Forwarding : A Distributed QoS MAC Protocol for Wireless Mesh
Express Forwarding : A Distributed QoS MAC Protocol for Wireless Mesh, Ph.D. benveniste@ieee.org Mesh 2008, Cap Esterel, France 1 Abstract Abundant hidden node collisions and correlated channel access
Video Transmission over Wireless LAN. Hang Liu Hang.liu@thomson.net
Video Transmission over Wireless LAN Hang Liu Hang.liu@thomson.net Page 1 Introduction! Introduction! Wi-Fi Multimedia and IEEE 802.11e for QoS Enhancement! Error Control Techniques Page 2 Introduction!
IEEE 802.11 Ad Hoc Networks: Performance Measurements
IEEE 8. Ad Hoc Networks: Performance Measurements G. Anastasi Dept. of Information Engineering University of Pisa Via Diotisalvi - 56 Pisa, Italy Email: g.anastasi@iet.unipi.it E. Borgia, M. Conti, E.
ISSN: 2319-5967 ISO 9001:2008 Certified International Journal of Engineering Science and Innovative Technology (IJESIT) Volume 2, Issue 5, September
Analysis and Implementation of IEEE 802.11 MAC Protocol for Wireless Sensor Networks Urmila A. Patil, Smita V. Modi, Suma B.J. Associate Professor, Student, Student Abstract: Energy Consumption in Wireless
Wireless LAN Services for Hot-Spot
Wireless LAN Services for Hot-Spot Woo-Yong Choi Electronics and Telecommunications Research Institute wychoi53@etri.re.kr ETRI Contents Overview Wireless LAN Services Current IEEE 802.11 MAC Protocol
TOWARDS STUDYING THE WLAN SECURITY ISSUES SUMMARY
TOWARDS STUDYING THE WLAN SECURITY ISSUES SUMMARY SUBMITTED TO THE KUMAUN UNIVERSITY, NAINITAL BY MANOJ CHANDRA LOHANI FOR THE AWARD OF THE DEGREE OF DOCTOR OF PHILOSOPHY IN COMPUTER SCIENCE UNDER THE
How To Make A Multi-User Communication Efficient
Multiple Access Techniques PROF. MICHAEL TSAI 2011/12/8 Multiple Access Scheme Allow many users to share simultaneously a finite amount of radio spectrum Need to be done without severe degradation of the
PERFORMANCE ANALYSIS OF THE IEEE 802.15.4 BASED ECG MONITORING NETWORK
PERFORMANCE ANALYSIS OF THE IEEE 802.15.4 BASED ECG MONITORING NETWORK Xuedong Liang 1,2 1 Department of Informatics University of Oslo Oslo, Norway email: xuedonl@ifi.uio.no Ilangko Balasingham 2 2 The
Bluetooth voice and data performance in 802.11 DS WLAN environment
1 (1) Bluetooth voice and data performance in 802.11 DS WLAN environment Abstract In this document, the impact of a 20dBm 802.11 Direct-Sequence WLAN system on a 0dBm Bluetooth link is studied. A typical
IEEE 802.15.1 Simulation and BER Analysis under the Interference
IEEE 802.15.1 Simulation and BER Analysis under the Interference Zahir Aalam, S Vhatkar, B. K. Mishra Thakur College of Engineering & Technology, Kandivali (E), Mumbai 101, M.S. India ABSTRACT There is
ZIGBEE 802.15.4. ECGR-6185 Advanced Embedded Systems. Charlotte. University of North Carolina-Charlotte. Chaitanya Misal Vamsee Krishna
ECGR-6185 Advanced Embedded Systems ZIGBEE 802.15.4 University of North Carolina-Charlotte Charlotte Chaitanya Misal Vamsee Krishna WPAN A personal area network (PAN) is a computer network used for communication
CS263: Wireless Communications and Sensor Networks
CS263: Wireless Communications and Sensor Networks Matt Welsh Lecture 4: Medium Access Control October 5, 2004 2004 Matt Welsh Harvard University 1 Today's Lecture Medium Access Control Schemes: FDMA TDMA
TL-WN612AG / TL-WN652AG / TL-WN653AG
TL-WN612AG / TL-WN652AG / TL-WN653AG 108M Dualband(2.4GHz/5GHz) Wireless Adapter Rev: 1.0.1 1910010033 COPYRIGHT & TRADEMARKS Specifications are subject to change without notice. is a registered trademark
Security in IEEE 802.11 WLANs
Security in IEEE 802.11 WLANs 1 IEEE 802.11 Architecture Extended Service Set (ESS) Distribution System LAN Segment AP 3 AP 1 AP 2 MS MS Basic Service Set (BSS) Courtesy: Prashant Krishnamurthy, Univ Pittsburgh
An Experimental Study of Throughput for UDP and VoIP Traffic in IEEE 802.11b Networks
An Experimental Study of Throughput for UDP and VoIP Traffic in IEEE 82.11b Networks Sachin Garg sgarg@avaya.com Avaya Labs Research Basking Ridge, NJ USA Martin Kappes mkappes@avaya.com Avaya Labs Research
Data Link Protocols. Link Layer Services. Framing, Addressing, link access: Error Detection:
Data Link Protocols Link Layer Services Framing, Addressing, link access: encapsulate datagram into frame, adding header, trailer channel access if shared medium MAC addresses used in frame headers to
Lecture 6.1 Introduction. Giuseppe Bianchi, Ilenia Tinnirello
PART 6 IEEE 802.11 Wireless LANs Lecture 6.1 Introduction WLAN History Ł Original goal: Deploy wireless Ethernet First generation proprietary solutions (end 80, begin 90) WaveLAN (AT&T)) HomeRF (Proxim)
Ajay Gummalla-July 2001
DOCSIS Overview Ajay Gummalla Ethernet in the First Mile Study Group July 2001 Ajay Gummalla-July 2001 1 HFC Plant Topology VIDEO combiner Fiber TX Fiber Fiber RX Tap CMTS Fiber RX Fiber Fiber TX 2way
Data Center Networks, Link Layer Wireless (802.11)
Internet-Technologien (CS262) Data Center Networks, Link Layer Wireless (802.11) 1.4.2015 Christian Tschudin Departement Mathematik und Informatik, Universität Basel 6 Wiederholung Warum «multiple access»?
Professur Technische Informatik Prof. Dr. Wolfram Hardt. Network Standards. and Technologies for Wireless Sensor Networks. Karsten Knuth 16.07.
Network Standards and Technologies for Wireless Sensor Networks Karsten Knuth 16.07.2008 Index 1. Motivation 2. Introduction 3. Bluetooth 4. ZigBee 5. nanonet 6. Roundup 16.07.2008 Network Standards 2
WIRELESS ETHERNET (IEEE 803.11)
WIRELESS ETHERNET (IEEE 803.11) Wireless LANs form a very small percentage of LANs in operation today, but their use is growing rapidly. Wireless LANs transmit data through the air using radio or infrared
WIRELESS NETWORKS. Erina Ferro
WIRELESS NETWORKS Erina Ferro National Research Council (C.N.R.) ISTI, Institute of C.N.R. C.N.R. Research Area, Via Moruzzi 1, 56124 Pisa, Italy Phone: +39-050-315 3070 Fax: +39-050-313 8091 E-mail: erina.ferro@isti.cnr.it
Wireless LAN Pen-Testing. Part I
Wireless LAN Pen-Testing Part I To know your Enemy, you must become your Enemy (Sun Tzu, 600 BC) Georg Penn 23.03.2012 Motivation Read manuals, documentation, standards Check sources for their reliability,