Wireless LANs. Characteristics Bluetooth. PHY MAC Roaming Standards
|
|
- Audrey Greene
- 10 months ago
- Views:
Transcription
1 Wireless LANs Characteristics PHY MAC Roaming Standards Bluetooth 1 Significant parts of slides are based on original material by Prof. Dr.-Ing. Jochen Schiller, FU-Berlin
2 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 lower bandwidth compared to wired networks (1-50 Mbit/s) typically much lower throughput (shared unreliable medium) many proprietary solutions, especially for higher bit-rates, standards take their time (e.g. IEEE ) products have to follow many national restrictions if working wireless, it takes a very long time to establish global solutions like, e.g., IMT
3 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 3
4 Comparison: infrared vs. radio transmission Infrared Advantages uses IR diodes, diffuse light, multiple reflections (walls, furniture etc.) simple, cheap, available in many mobile devices no licenses needed simple shielding possible Disadvantages Example interference by sunlight, heat sources etc. many things shield or absorb IR light low bandwidth IrDA (Infrared Data Association) interface available everywhere Radio Advantages typically using the license free ISM band at 2.4 GHz experience from wireless WAN and mobile phones can be used coverage of larger areas possible (radio can penetrate walls, furniture etc.) Disadvantages Example very limited license free frequency bands shielding more difficult, interference with other electrical devices WaveLAN, HIPERLAN, Bluetooth 4
5 802.11: Ad Hoc Network Base Service Set 5
6 Network Infrastructure Extended Service Set 6
7 Architecture of an ad-hoc network LAN STA 1 IBSS 1 STA 3 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 STA 2 IBSS 2 STA 5 STA LAN 7
8 Architecture of an infrastructure network STA 1 ESS LAN BSS 1 Access Point BSS 2 Distribution System Access Point 802.x LAN Portal 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 Portal station integrated into the wireless LAN and the distribution system bridge to other (wired) networks Distribution System interconnection network to form one logical network (EES: Extended Service Set) based on several BSS 8
9 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 9
10 Layers and functions MAC access mechanisms, fragmentation, encryption MAC Management synchronization, roaming, MIB, power 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 DLC PHY LLC MAC PLCP PMD MAC Management PHY Management Station Management 10
11 Physical layer 3 versions: 2 radio (type. 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) Infrared 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 nm, diffuse light, typ. 10 m range carrier detection, energy detection, synchonization 11
12 FHSS PHY packet format Synchronization synch with pattern SFD (Start Frame Delimiter) 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 12
13 DSSS PHY packet format 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 Length future use, 00: compliant length of the payload HEC (Header Error Check) protection of signal, service and length, x 16 +x 12 +x variable synchronization SFD signal service length HEC payload bits PLCP preamble PLCP header 13
14 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 14
15 MAC layer II Priorities defined through different inter frame spaces no guaranteed, hard priorities SIFS (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 DIFS medium busy PIFS SIFS contention next frame 15 direct access if medium is free DIFS t
16 CSMA/CA access method I DIFS DIFS contention window (randomized back-off mechanism) medium busy direct access if medium is free DIFS slot time next frame t 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) 16
17 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 17
18 CSMA/CA access method II Sending unicast packets station has to wait for DIFS before sending data receivers acknowledge at once (after waiting for SIFS) if the packet was received correctly (CRC) automatic retransmission of data packets in case of transmission errors sender DIFS data receiver SIFS ACK other stations waiting time DIFS contention data t 18
19 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 SIFS by receiver (if ready to receive) sender can now send data at once, acknowledgement via ACK other stations store medium reservations distributed via RTS and CTS sender receiver DIFS RTS SIFS CTS SIFS data SIFS ACK other stations NAV (RTS) NAV (CTS) defer access DIFS contention data t 19
20 Fragmentation sender receiver DIFS RTS SIFS CTS SIFS frag 1 SIFS ACK SIFS 1 frag 2 SIFS ACK2 other stations NAV (RTS) NAV (CTS) NAV (frag 1 ) NAV (ACK 1 ) DIFS contention data t 20
21 DFWMAC-PCF I t 0 t 1 SuperFrame medium busy point coordinator PIFS D 1 SIFS SIFS D 2 SIFS SIFS wireless stations U 1 U 2 stations NAV NAV 21
22 DFWMAC-PCF II t 2 t 3 t 4 PIFS SIFS CFend point coordinator D 3 D 4 SIFS wireless stations U 4 stations NAV NAV contention free period contention period t 22
23 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 bytes sending time, checksum, frame control, data Duration/ ID Address 1 Address 2 Address 3 Sequence Control Frame Control Protocol version Type Subtype To DS More Frag Power Retry Mgmt Address Data 4 bits From DS More Data WEP Order CRC 23
24 MAC address format scenario to DS from address 1 address 2 address 3 address 4 DS ad-hoc network 0 0 DA SA BSSID - infrastructure 0 1 DA BSSID SA - network, from AP infrastructure 1 0 BSSID SA DA - network, to AP infrastructure network, within DS 1 1 RA TA DA SA DS: Distribution System AP: Access Point DA: Destination Address SA: Source Address BSSID: Basic Service Set Identifier RA: Receiver Address TA: Transmitter Address 24
25 MAC management Synchronization try to find a LAN, try to stay within a LAN timer etc. 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 25
26 Synchronization using a Beacon (infrastructure) beacon interval access point medium B B B B busy busy busy busy value of the timestamp B beacon frame t 26
27 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 27
28 Roaming No or bad connection? Then perform: Scanning scan the environment, i.e., listen into the medium for beacon signals or send probes into the medium and wait for an answer Reassociation Request station sends a request to one or several AP(s) Reassociation Response success: AP has answered, station can now participate failure: continue scanning AP accepts Reassociation Request signal the new station to the distribution system the distribution system updates its data base (i.e., location information) typically, the distribution system now informs the old AP so it can release resources 28
29 Handoff 29
30 WLAN: IEEE b Data rate 30 1, 2, 5.5, 11 Mbit/s, depending on SNR User data rate max. approx. 6 Mbit/s Transmission range Frequency Security Cost Availability 300m outdoor, 30m indoor Max. data rate ~10m indoor Free 2.4 GHz ISM-band Limited, WEP insecure, SSID 50 adapter, 200 base station, dropping Many products, many vendors Connection set-up time Connectionless/always on Quality of Service Typ. Best effort, no guarantees (unless polling is used, limited support in products) Manageability Limited (no automated key distribution, sym. Encryption) Special Advantages/Disadvantages Advantage: many installed systems, lot of experience, available worldwide, free ISM-band, many vendors, integrated in laptops, simple system Disadvantage: heavy interference on ISM-band, no service guarantees, slow relative speed only
31 IEEE b PHY frame formats Long PLCP PPDU format variable synchronization SFD signal service length HEC payload bits PLCP preamble PLCP header 192 µs at 1 Mbit/s DBPSK 1, 2, 5.5 or 11 Mbit/s Short PLCP PPDU format (optional) variable short synch. SFD signal service length HEC payload bits PLCP preamble (1 Mbit/s, DBPSK) PLCP header (2 Mbit/s, DQPSK) 96 µs 2, 5.5 or 11 Mbit/s 31
32 Channel selection (non-overlapping) Europe (ETSI) channel 1 channel 7 channel MHz [MHz] US (FCC)/Canada (IC) channel 1 channel 6 channel MHz [MHz] 32
33 WLAN: IEEE a Data rate 6, 9, 12, 18, 24, 36, 48, 54 Mbit/s, depending on SNR User throughput (1500 byte packets): 5.3 (6), 18 (24), 24 (36), 32 (54) 6, 12, 24 Mbit/s mandatory Transmission range Frequency Security Cost 100m outdoor, 10m indoor E.g., 54 Mbit/s up to 5 m, 48 up to 12 m, 36 up to 25 m, 24 up to 30m, 18 up to 40 m, 12 up to 60 m Free , , GHz ISM-band Availability Limited, WEP insecure, SSID 280 adapter, 500 base station Some products, some vendors Connection set-up time Connectionless/always on Quality of Service Manageability Typ. best effort, no guarantees (same as all products) Limited (no automated key distribution, sym. Encryption) Special Advantages/Disadvantages Advantage: fits into 802.x standards, free ISM-band, available, simple system, uses less crowded 5 GHz band Disadvantage: stronger shading due to higher frequency, no QoS 33
34 IEEE a PHY frame format variable 6 variable bits rate reserved length parity tail service payload tail pad PLCP header PLCP preamble signal data 12 1 variable symbols 6 Mbit/s 6, 9, 12, 18, 24, 36, 48, 54 Mbit/s 34
35 Operating channels for a / US U-NII channel [MHz] 16.6 MHz channel center frequency = *channel number [MHz] [MHz] 16.6 MHz 35
36 OFDM in IEEE a (and HiperLAN2) OFDM with 52 used subcarriers (64 in total) 48 data + 4 pilot (plus 12 virtual subcarriers) khz spacing pilot khz channel center frequency subcarrier number 36
37 WLAN: IEEE future developments (08/2004) d: Regulatory Domain Update completed e: MAC Enhancements QoS ongoing Enhance the current MAC to expand support for applications with Quality of Service requirements, and in the capabilities and efficiency of the protocol f: Inter-Access Point Protocol completed Establish an Inter-Access Point Protocol for data exchange via the distribution system g: Data Rates > 20 Mbit/s at 2.4 GHz; 54 Mbit/s, OFDM completed h: Spectrum Managed a (DCS, TPC) completed i: Enhanced Security Mechanisms ongoing Enhance the current MAC to provide improvements in security n: Data Rates > 100 Mbit/s ongoing Study Groups 5 GHz (harmonization ETSI/IEEE) closed Radio Resource Measurements started High Throughput started 37
38 Bluetooth Idea Universal radio interface for ad-hoc wireless connectivity Interconnecting computer and peripherals, handheld devices, PDAs, cell phones replacement of IrDA Embedded in other devices, goal: 5 /device (2002: 50 /USB bluetooth) Short range (10 m), low power consumption, license-free 2.45 GHz ISM Voice and data transmission, approx. 1 Mbit/s gross data rate One of the first modules (Ericsson). 38
39 Bluetooth History 1994: Ericsson (Mattison/Haartsen), MC-link project Renaming of the project: Bluetooth according to Harald Blåtand Gormsen [son of Gorm], King of Denmark in the 10 th century 1998: foundation of Bluetooth SIG, : erection of a rune stone at Ercisson/Lund ;-) (was: ) 2001: first consumer products for mass market, spec. version 1.1 released Special Interest Group Original founding members: Ericsson, Intel, IBM, Nokia, Toshiba Added promoters: 3Com, Agere (was: Lucent), Microsoft, Motorola > 2500 members Common specification and certification of products 39
40 Characteristics 2.4 GHz ISM band, 79 (23) RF channels, 1 MHz carrier spacing Channel 0: 2402 MHz channel 78: 2480 MHz G-FSK modulation, mw transmit power FHSS and TDD Frequency hopping with 1600 hops/s Hopping sequence in a pseudo random fashion, determined by a master Time division duplex for send/receive separation Voice link SCO (Synchronous Connection Oriented) FEC (forward error correction), no retransmission, 64 kbit/s duplex, pointto-point, circuit switched Data link ACL (Asynchronous ConnectionLess) Asynchronous, fast acknowledge, point-to-multipoint, up to kbit/s symmetric or 723.2/57.6 kbit/s asymmetric, packet switched Topology Overlapping piconets (stars) forming a scatternet 40
41 Piconet Collection of devices connected in an ad hoc fashion One unit acts as master and the others as slaves for the lifetime of the piconet S P M S P Master determines hopping pattern, slaves have to synchronize SB S Each piconet has a unique hopping pattern P SB Participation in a piconet = synchronization to hopping sequence Each piconet has one master and up to 7 simultaneous slaves (> 200 could be parked) 41 M=Master S=Slave P=Parked SB=Standby
42 Forming a piconet All devices in a piconet hop together Master gives slaves its clock and device ID Addressing Hopping pattern: determined by device ID (48 bit, unique worldwide) Phase in hopping pattern determined by clock Active Member Address (AMA, 3 bit) Parked Member Address (PMA, 8 bit) SB SB SB SB SB SB SB SB SB S SB P P M SB S S P 42
43 Scatternet Linking of multiple co-located piconets through the sharing of common master or slave devices Devices can be slave in one piconet and master of another Communication between piconets Devices jumping back and forth between the piconets P S S Piconets (each with a capacity of < 1 Mbit/s) S SB M S P M P M=Master S=Slave P=Parked SB=Standby P SB S SB 43
44 Example: Bluetooth/USB adapter 44
45 WPAN: IEEE Bluetooth Data rate 45 Synchronous, connection-oriented: 64 kbit/s Asynchronous, connectionless Transmission range Frequency Security Cost Availability kbit/s symmetric / 57.6 kbit/s asymmetric POS (Personal Operating Space) up to 10 m with special transceivers up to 100 m Free 2.4 GHz ISM-band Challenge/response (SAFER+), hopping sequence 50 adapter, drop to 5 if integrated Integrated into some products, several vendors Connection set-up time Depends on power-mode Max. 2.56s, avg. 0.64s Quality of Service Manageability Guarantees, ARQ/FEC Public/private keys needed, key management not specified, simple system integration Special Advantages/Disadvantages Advantage: already integrated into several products, available worldwide, free ISM-band, several vendors, simple system, simple ad-hoc networking, peer to peer, scatternets Disadvantage: interference on ISM-band, limited range, max. 8 devices/network&master, high set-up latency
Chapter 7: Wireless LANs
Mobile Communications Chapter 7: Wireless LANs Characteristics IEEE 802.11 (PHY, MAC, Roaming,.11a, b, g, h, i, n z) Bluetooth / IEEE 802.15.x IEEE 802.16/.20/.21/.22 RFID Comparison Prof. Jó Ueyama courtesy
Mobile & Wireless Networking. Lecture 7: Wireless LAN
192620010 Mobile & Wireless Networking Lecture 7: Wireless LAN [Schiller, Section 7.3] [Reader, Part 6] [Optional: "IEEE 802.11n Development: History, Process, and Technology", Perahia, IEEE Communications
WLAN 1 IEEE Basic Connectivity. Manuel Ricardo. Faculdade de Engenharia da Universidade do Porto
WLAN 1 IEEE 802.11 Basic Connectivity Manuel Ricardo Faculdade de Engenharia da Universidade do Porto WLAN 2 Acknowledgements Based on Jochen Schiller slides Supporting text» Jochen Schiller, Mobile Comunications,
WLAN 1 IEEE Manuel Ricardo. Faculdade de Engenharia da Universidade do Porto
WLAN 1 IEEE 802.11 Basic Connectivity Manuel Ricardo Faculdade de Engenharia da Universidade do Porto WLAN 2 Acknowledgements Based on Jochen Schiller slides Supporting text» Jochen Schiller, Mobile Comunications,
Lecture 16: QoS and "
Lecture 16: QoS and 802.11" CSE 123: Computer Networks Alex C. Snoeren HW 4 due now! Lecture 16 Overview" Network-wide QoS IntServ DifServ 802.11 Wireless CSMA/CA Hidden Terminals RTS/CTS CSE 123 Lecture
IEEE WLANs (WiFi) Part II/III System Overview and MAC Layer
IEEE 802.11 WLANs (WiFi) Part II/III System Overview and MAC Layer Design goals for wireless LANs (WLANs) Global, seamless operation Low power for battery use No special permissions or licenses needed
MAC in /20/06
MAC in 802.11 2/20/06 MAC Multiple users share common medium. Important issues: Collision detection Delay Fairness Hidden terminals Synchronization Power management Roaming Use 802.11 as an example to
Introduction to IEEE
Introduction to IEEE 802.11 Characteristics of wireless LANs Advantages very flexible within the reception area Ad hoc networks without previous planning possible (almost) no wiring difficulties more robust
standard. Acknowledgement: Slides borrowed from Richard Y. 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
MOBILE COMPUTING. Bluetooth 9/20/15. CSE 40814/60814 Fall Basic idea
OBILE COUTING CE 40814/60814 Fall 2015 Bluetooth Basic idea Universal radio interface for ad-hoc wireless connectivity Interconnecting computer and peripherals, handheld devices, DAs, cell phones replacement
CS 348: Computer Networks. - WiFi (contd.); 16 th Aug Instructor: Sridhar Iyer IIT Bombay
CS 348: Computer Networks - WiFi (contd.); 16 th Aug 2012 Instructor: Sridhar Iyer IIT Bombay Clicker-1: Wireless v/s wired Which of the following differences between Wireless and Wired affect a CSMA-based
3.1. Introduction to WLAN IEEE
3.1. Introduction to WLAN IEEE 802.11 WCOM, WLAN, 1 References [1] J. Schiller, Mobile Communications, 2nd Ed., Pearson, 2003. [2] Martin Sauter, "From GSM to LTE", chapter 6, Wiley, 2011. [3] wiki to
Chapter 3: Overview 802 Standard
Chapter 3: Overview 802 Standard IEEE - Institute of Electrical and Electronics Engineers What is the IEEE? international non-profit, professional organization for the advancement of technology related
Wireless# Guide to Wireless Communications. Objectives
Wireless# Guide to Wireless Communications Chapter 7 Low-Speed Wireless Local Area Networks Objectives Describe how WLANs are used List the components and modes of a WLAN Describe how an RF WLAN works
original standard a transmission at 5 GHz bit rate 54 Mbit/s b support for 5.5 and 11 Mbit/s e QoS
IEEE 802.11 The standard defines a wireless physical interface and the MAC layer while LLC layer is defined in 802.2. The standardization process, started in 1990, is still going on; some versions are:
IEEE Integrated Communication Systems Group Ilmenau University of Technology
IEEE 802.11 Integrated Communication Systems Group Ilmenau University of Technology Characteristics of Wireless LANs Advantages very flexible alternative to wired LANs (almost) no wiring difficulties (e.g.
Wireless LANs. ITS 413 Internet Technologies and Applications
Wireless LANs ITS 413 Internet Technologies and Applications Aim: Aim and Contents Understand how IEEE 802.11 wireless LANs work Understand what influences the performance of wireless LANs Contents: IEEE
CSC344 Wireless and Mobile Computing. Department of Computer Science COMSATS Institute of Information Technology
CSC344 Wireless and Mobile Computing Department of Computer Science COMSATS Institute of Information Technology Wireless Local Area Networks (WLANs) Part I Almost all wireless LANs now are IEEE 802.11
Wireless Local Area Networks (WLANs)) and Wireless Sensor Networks (WSNs) Computer Networks: Wireless Networks 1
Wireless Local Area Networks (WLANs)) and Wireless Sensor Networks (WSNs) Computer Networks: Wireless Networks 1 Wireless Local Area Networks The proliferation of laptop computers and other mobile devices
Mobile Communications I
Mobile Communications I Prof. Dr.-Ing. Rolf Kraemer chair owner telefon: 0335 5625 342 fax: 0335 5625 671 e-mail: kraemer [ at ] ihp-microelectronics.com web: Mobile Communications Chapter 4: Wireless
Wireless Local Area Networks. Networks: Wireless LANs 1
Wireless Local Area Networks Networks: Wireless LANs 1 Wireless Local Area Networks The proliferation of laptop computers and other mobile devices (PDAs and cell phones) created an obvious application
Wireless Local Area Networks (WLANs) and Wireless Sensor Networks (WSNs) Primer. Computer Networks: Wireless LANs
Wireless Local Area Networks (WLANs) and Wireless Sensor Networks (WSNs) Primer 1 Wireless Local Area Networks (WLANs) The proliferation of laptop computers and other mobile devices (PDAs and cell phones)
IEEE Technical Tutorial. Introduction. IEEE 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
Communication Systems. WPAN: Bluetooth. Page 1
Communication Systems WPAN: Bluetooth Page 1 Outline Historical perspective Piconet Scatternet Lattency modes Applications Page 2 Bluetooth Bluetooth (BT) wireless technology is a short-range communications
IEEE Wireless LANs
Unit 11 IEEE 802.11 Wireless LANs Shyam Parekh IEEE 802.11 Wireless LANs References Standards Basics Physical Layer 802.11b 802.11a MAC Framing Details Management PCF QoS (802.11e) Security Take Away Points
Multiple Access Links and Protocols
Multiple Access Links and Protocols Two types of links : point-to-point PPP for dial-up access point-to-point link between Ethernet switch and host broadcast (shared wire or medium) old-fashioned Ethernet
outline background & overview mac & phy wlan management security
IEEE 802.11a/g WLAN outline background & overview mac & phy wlan management security WLAN benefits flexibility & mobility installation scalability disadvantages distance security performance IEEE 802.11a
Wireless Local Area Network (IEEE )
Wireless Local Area Network (IEEE 802.11) -IEEE 802.11 Specifies a single Medium Access Control (MAC) sublayer and 3 Physical Layer Specifications. Stations can operate in two configurations : Ad-hoc mode
Wireless Data Networking IEEE & Overview of IEEE b
Wireless Data Networking IEEE 802.11 & Overview of IEEE 802.11b Dr. Arian Durresi The Ohio State University Columbus, OH 43210 durresi@cis.ohio-state.edu 1 Overview Wireless Application Market Wireless
Mobile Communications Chapter 5: Wireless local area networks
Mobile Communications Chapter 5: Wireless local area networks Holger Karl Computer Networks Group Universität Paderborn Goals of this chapter Look at two most prominent examples of local, non-cellular
Internet Structure. network edge:
Midterm Review Internet Structure network edge: Hosts: clients and servers Server often in data centers access networks, physical media:wired, wireless communication links network core: interconnected
Bluetooth. Basic idea
Bluetooth Basic idea Universal radio interface for ad-hoc wireless connectivity Interconnecting computer and peripherals, handheld devices, DAs, cell phones replacement of IrDA Embedded in other devices,
CHAPTER 8: LAN Standards
CHAPTER 8: LAN Standards DR. BHARGAVI GOSWAMI, ASSOCIATE PROFESSOR HEAD, DEPARTMENT OF COMPUTER SCIENCE, GARDEN CITY COLLEGE BANGALORE. LAN STRUCTURE NETWORK INTERFACE CARD MEDIUM ACCESS CONTROL SUB LAYER
Architecture. Copyright :I1996 IEEE. All rights reserved. This contains parts from an unapproved draft, subject to change
802.11 Architecture Copyright :I1996 IEEE. All rights reserved. This contains parts from an unapproved draft, subject to change What is unique about wireless? Difficult media - interference and noise -
Wireless Sensor Networks
Wireless Sensor Networks 11th Lecture 29.11.2006 Christian Schindelhauer schindel@informatik.uni-freiburg.de 1 Bluetooth in WSN? There are several commercially available MAC protocol/products Wi-Fi Bluetooth
Last Lecture: Data Link Layer
Last Lecture: Data Link Layer 1. Design goals and issues 2. (More on) Error Control and Detection 3. Multiple Access Control (MAC) 4. Ethernet, LAN Addresses and ARP 5. Hubs, Bridges, Switches 6. Wireless
Laboratory of Nomadic Communication. Quick introduction to IEEE
Laboratory of Nomadic Communication Quick introduction to IEEE 802.11 Let s play 802.11 game Wireless LAN Standard A quick introduction to the IEEE 802.11 standard IEEE 802.11 standard! Definition of wireless
IEEE Wireless LANs Part I: Basics
IEEE 802.11 Wireless LANs Part I: Basics Raj Jain Professor of Computer Science and Engineering Washington University in Saint Louis Saint Louis, MO 63130 Jain@cse.wustl.edu Audio/Video recordings of this
Chapter 6 Wireless and Mobile Networks
Chapter 6 Wireless and Mobile Networks Computer Networking: A Top Down Approach Featuring the Internet, 3 rd edition. Jim Kurose, Keith Ross Addison-Wesley, July 2004. 6: Wireless and Mobile Networks 6
Wireless Networks. CSE 3461: Introduction to Computer Networking Reading: , Kurose and Ross
Wireless Networks CSE 3461: Introduction to Computer Networking Reading: 6.1 6.3, Kurose and Ross 1 Wireless Networks Background: Number of wireless (mobile) phone subscribers now exceeds number of wired
Wireless LAN -Architecture
Wireless LAN -Architecture IEEE has defined the specifications for a wireless LAN, called IEEE 802.11, which covers the physical and data link layers. Basic Service Set (BSS) Access Point (AP) Distribution
Lesson 2-3: The IEEE x MAC Layer
Module 2: Establishing Wireless Connectivity Lesson 2-3: The IEEE 802.11x MAC Layer Lesson Overview This lesson describes basic IEEE 802.11x MAC operation, beginning with an explanation of contention schemes
e-pg Pathshala Quadrant 1 e-text
e-pg Pathshala Subject : Computer Science Module: Bluetooth Paper: Computer Networks Module No: CS/CN/37 Quadrant 1 e-text In our journey on networks, we are now exploring wireless networks. We looked
Bluetooth: Short-range Wireless Communication
Bluetooth: Short-range Wireless Communication Wide variety of handheld devices Smartphone, palmtop, laptop Need compatible data communication interface Complicated cable/config. problem Short range wireless
Outline. CS5984 Mobile Computing. IEEE 802 Architecture 1/7. IEEE 802 Architecture 2/7. IEEE 802 Architecture 3/7. Dr. Ayman Abdel-Hamid, CS5984
CS5984 Mobile Computing Dr. Ayman Abdel-Hamid Computer Science Department Virginia Tech Outline IEEE 82 Architecture IEEE 82. Wireless LANs Based on Chapter 4 in Wireless Communications and Networks, William
Mobile Communications Chapter 5: Wireless local area networks
Mobile Communications Chapter 5: Wireless local area networks Holger Karl Computer Networks Group Universität Paderborn Goals of this chapter Look at two most prominent examples of local, non-cellular
Extending or Interconnecting LANS. Physical LAN segment. Virtual LAN. Forwarding Algorithm 11/9/15. segments. VLAN2, Port3. VLAN1, Port1.
Physical LAN segment q Hosts connected on the same physical LAN segment q Same subnet; L2 forwarding q ARP (IPè MAC) L2 frame (S, D), send q Scale? Extending or Interconnecting LANS q q q Why not just
CHAPTER 11 WIRELESS LAN TECHNOLOGY AND THE IEEE WIRELESS LAN STANDARD
CHAPTER 11 WIRELESS LAN TECHNOLOGY AND THE IEEE 802.11 WIRELESS LAN STANDARD These slides are made available to faculty in PowerPoint form. Slides can be freely added, modified, and deleted to suit student
7. Wireless Local Area Networks. Characteristics of Wireless LANs
7. Wireless Local Area Networks Characteristics IEEE 802.11 HIPERLAN, WATM, BRAN, HIPERLAN2 Bluetooth RF Comparison 2005 Burkhard Stiller and Jochen Schiller FU Berlin M7 1 Characteristics of Wireless
Wireless Communication and Networking CMPT 371
Wireless Communication and Networking CMPT 371 Wireless Systems: AM, FM Radio TV Broadcast Satellite Broadcast 2-way Radios Cordless Phones Satellite Links Mobile Telephony Systems Wireless Local Loop
Overview Computer Networks. Single Cell Wireless LAN Configuration. Applications - LAN Extension. Applications Cross-Building Interconnect
168 430 Computer Networks Chapter 17 Wireless LANs Overview A wireless LAN uses wireless transmission medium Used to have high prices, low data rates, occupational safety concerns, and licensing requirements
Experimental Study on Co-existence of b with Alien Devices
Experimental Study on Co-existence of 8.b with Alien Devices Javier del Prado and Sunghyun Choi Philips Research Briarcliff USA, Briarcliff Manor, New York Email: {javier.delprado,sunghyun.choi}@philips.com
WiFi / IEEE WLAN
WiFi / IEEE 802.11 - WLAN Lecturer: Carlos Rey-Moreno carlos.reymoreno@gmail.com Networking Course Honors on Computer Science University of the Western Cape 04 Feb - 2013 Why Wireless? A lot of pros...
WLAN Technology: LAN: a review WLAN: applications & key parameters. protocol architectures
WLAN Technology: LAN: a review WLAN: applications & key parameters IEEE 802.11 protocol architectures LOCAL AREA NETWORKS LAN ROUTER INTERNET WEB SERVER RAM Ethernet Processor RAM ROM A C NIC with unique
CSCD 433 Network Programming Fall Lecture 7 Ethernet and Wireless
CSCD 433 Network Programming Fall 2016 Lecture 7 Ethernet and Wireless 802.11 1 Topics 802 Standard MAC and LLC Sublayers Review of MAC in Ethernet MAC in 802.11 Wireless 2 IEEE Standards In 1985, Computer
Medium Access Control Sublayer
Wireless (WLAN) Medium Access Control Sublayer Mahalingam Mississippi State University, MS October 20, 2014 Outline Medium Access Protocols Wireless (WLAN) 1 Medium Access Protocols ALOHA Slotted ALOHA
Wireless# Guide to Wireless Communications. Objectives
Wireless# Guide to Wireless Communications Chapter 8 High-Speed WLANs and WLAN Security Objectives Describe how IEEE 802.11a networks function and how they differ from 802.11 networks Outline how 802.11g
Wireless Local Area Networks: Recent Developments
Wireless Local Area Networks: Recent Developments Ohio Highway Patrol Columbus, OH 43210 http://www.cis.ohio-state.edu/~jain/ 13-1 Overview Spread Spectrum Wireless local area networks Wireless LAN standard:
Wireless and WiFi. Daniel Zappala. CS 460 Computer Networking Brigham Young University
Wireless and WiFi Daniel Zappala CS 460 Computer Networking Brigham Young University Wireless Networks 2/28 mobile phone subscribers now outnumber wired phone subscribers similar trend likely with Internet
Multiple Access Links and Protocols
Multiple Access Links and Protocols Two types of links : point-to-point PPP for dial-up access point-to-point link between Ethernet switch and host broadcast (shared wire or medium) old-fashioned Ethernet
Master thesis 60 credits
UNIVERSITY OF OSLO Department of informatics Capacity and performance study of IEEE 802.11e in WLANs and ad hoc networks Master thesis 60 credits Frank Roar Mjøberg 2. May 2007 Abstract Today, WLANs allow
Wireless Networking based on Chapter 15 of CompTIA Network+ Exam Guide, 4th ed., Mike Meyers
Wireless Networking 802.11 based on Chapter 15 of CompTIA Network+ Exam Guide, 4th ed., Mike Meyers topics Standards Technical Concepts Implementation Troubleshooting 802.11 timeline source: Anandtech
WPAN-like Systems. UWB Ultra Wide Band. IrDA Infrared Data Association. Bluetooth. Z-Wave. WPAN Wireless Personal Area Network
WPAN-like Systems WPAN Wireless Personal Area Network PAN: Personal Area Network. Small, within a few meters. WPAN: Wireless PAN. Mostly short-range, low-power, lowrate networks. More or less self-organizing.
Figure.2. Hidden & Exposed node problem
Efficient Throughput MAC Protocol in Ad-hoc Network s Rahul Mukherjee, HOD and Assistant Professor, Electronics & Communication Department, St. Aloysius Institute of Technology (SAIT), Jabalpur, Rajiv
CS263: Wireless Communications and Sensor Networks
CS263: Wireless Communications and Sensor Networks Matt Welsh Lecture 5: The 802.11 Standard October 7, 2004 2004 Matt Welsh Harvard University 1 All about 802.11 Today's Lecture CSMA/CD MAC and DCF WEP
Analysis of IEEE e for QoS Support in Wireless LANs
Analysis of IEEE 802.11e for QoS Support in Wireless LANs Stefan Mangold, Sunghyun Choi, Guido R. Hiertz, Ole Klein IEEE Wireless Communications, December 2003 Presented by Daeseon Park, Student No.2005-30231
Mobile and Sensor Systems
Mobile and Sensor Systems Lecture 2: Mobile Medium Access Control Protocols and Wireless Systems Dr Cecilia Mascolo In this lecture We will describe medium access control protocols and wireless systems
Wireless Local Area Networks (WLANs)
Wireless Local Area Networks (WLANs) WLAN Technologies IEEE 802.11 Hiperlan Pag. 1 IEEE 802.11 Bibliography 1. Tutorial on 802.11 WLAN 802.11,by Crow, in the IEEE Communications Magazine, 1997 (in English)
Bluetooth Demystified
Bluetooth Demystified S-72.4210 Postgraduate Course in Radio Communications Er Liu liuer@cc.hut.fi -10 Content Outline Bluetooth History Bluetooth Market and Applications Bluetooth Protocol Stacks Radio
Wireless LANs. The Protocol Stack The Physical Layer The MAC Sublayer Protocol The Frame Structure Services 802.
Wireless LANs The 802.11 Protocol Stack The 802.11 Physical Layer The 802.11 MAC Sublayer Protocol The 802.11 Frame Structure Services 56 802.11 The 802.11 Working Group The IEEE 802.11 was formed in July
Mobile Radio Communications
Session 7: Wireless networks & WLANs Session 7, page 1 Backbone network MSC PSTN PLMN BSC Session 7, page 2 Public switched telephone network (PSTN) PABX central office local exchange long distance subscriber
Junseok Kim Wireless Networking Lab (WINLAB) Konkuk University, South Korea
Junseok Kim Wireless Networking Lab (WINLAB) Konkuk University, South Korea http://usn.konkuk.ac.kr/~jskim 1 IEEE 802.x Standards 802.11 for Wireless Local Area Network 802.11 legacy clarified 802.11 legacy
Bluetooth Vs : state-of-the-art and research challenges
Bluetooth Vs. 802.11: state-of-the-art and research challenges Pravin Bhagwat ReefEdge, Inc. pravin@reefedge.com or pravin@acm.org http://www.cs.umd.edu/~pravin WINLAB, Rutgers Oct 28, 2001 10/29/2001
Wireless Networks (MAC)
802.11 Wireless Networks (MAC) Kate Ching-Ju Lin ( 林靖茹 ) Academia Sinica 2016.03.18 CSIE, NTU Reference 1. A Technical Tutorial on the IEEE 802.11 Protocol By Pablo Brenner online: http://www.sss-mag.com/pdf/802_11tut.pdf
Chapter 4: The Medium Access Layer
Chapter 4: The Medium Access Layer Computer Networks Maccabe Computer Science Department The University of New Mexico September 2002 Medium Access Layer Point-to-point versus broadcast networks Broadcast
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)
IEEE Notes. 1 Local Area Networks. 2 Protocols. 3 Network Model
IEEE 802.11 Notes This document provides a primer on the layered Internet protocol stack and its correspondence to the IEEE 802.11 standard. The components and architecture of an 802.11 network along with
Redes de Computadores. Medium Access Control
Redes de Computadores Medium Access Control Manuel P. Ricardo Faculdade de Engenharia da Universidade do Porto 1 » How to control the access of computers to a communication medium?» What is the ideal Medium
Analyzing the RTS/CTS Mechanism in the DFWMAC Media Access Protocol for Wireless LANs
Presented at IFIP TC6 Workshop Personal Wireless Comm. April 95 Prague, Czech Rep. Analyzing the RTS/CTS Mechanism in the DFWMAC Media Access Protocol for Wireless LANs Jost Weinmiller*, Hagen Woesner*,
Computer Networks II Advanced Features (T )
Computer Networks II Advanced Features (T-110.5111) Bluetooth, PhD Assistant Professor DCS Research Group Based on slides previously done by Matti Siekkinen, reused with permission For classroom use only,
U S E R M A N U A L b/g PC CARD
U S E R M A N U A L 802.11b/g PC CARD Table of Content CHAPTER 1 INTRODUCTION... 1 1.1 WIRELESS LAN FEATURE FUNCTIONS... 1 1.2 REGULATORY NOTICE... 1 1.2.1 FCC Class B Statement...1 1.2.2 Canadian Regulatory
Topic: Wireless and Mobile Networks
Topic: Wireless and Mobile Networks What you will learn IEEE 802.11 Mobile IPv6 IEEE 802.11e Centralized Architectures and CAPWAP A glance at VANETs 1/77 Elements of a wireless network Coverage area network
The MAC layer in wireless networks
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?
M06:Wireless and Mobile Networks. Corinna Schmitt
M06:Wireless and Mobile Networks Corinna Schmitt corinna.schmitt@unibas.ch Acknowledgement 2016 M06 2 Background q # wireless (mobile) phone subscribers now exceeds # wired phone subscribers (5-to-1)!
HOW WI-FI WORKS AND WHY IT BREAKS WI-FI MECHANICS
HOW WI-FI WORKS AND WHY IT BREAKS WI-FI MECHANICS THE WI-FI COMMUNICATION PROCESS MECHANICS MECHANICS: HOW WI-FI COMMUNICATION WORKS WHAT WE LL BE COVERING Brief Discourse on Frame Types Discovery of Wi-Fi
CMPE 257: Wireless and Mobile Networking
CMPE 257: Wireless and Mobile Networking Katia Obraczka Computer Engineering UCSC Baskin Engineering Lecture 3 CMPE 257 Winter'11 1 Announcements Accessing secure part of the class Web page: User id: cmpe257.
Medium Access Control
Medium Access Control All material copyright 1996-2009 J.F Kurose and K.W. Ross, All Rights Reserved 5: DataLink Layer 5-1 Link Layer Introduction and services Multiple access protocols Ethernet Wireless
ISSN: International Journal of Advanced Research in Computer Engineering & Technology Volume 1, Issue 5, July 2012
Optimized MAC Protocol with Power Efficiency in Mobile Ad-hoc Network Rahul Mukherjee HOD and Assistant Professor, Electronics & Communication Department, St. Aloysius Institute of Technology (SAIT), Jabalpur,
Wireless# Guide to Wireless Communications. Objectives
Wireless# Guide to Wireless Communications Chapter 6 High Rate Wireless Personal Area Networks Objectives Define a high rate wireless personal area network (HR WPAN) List the different HR WPAN standards
Medium Access and Routing In Multi Hop Wireless Infrastructures
Electrical Engineering, Mathematics and Computer Science Medium Access and Routing In Multi Hop Wireless Infrastructures Ayman Wazwaz Master Thesis M.Sc. Telematics Project Supervisors: Dr. ir. Geert Heijenk
Wireless PCI PCMCIA Super G 108 Mbit. Manual
Wireless PCI PCMCIA Super G 108 Mbit Dear Customer, Manual thanks for choosing Hamlet. Please carefully follow the instructions for its use and maintenance and, once this item has run its life span, we
Wireless Security Protocol Analysis and Design. Artoré & Bizollon : Wireless Security Protocol Analysis and Design
Protocol Analysis and Design 1 Networks 1. WIRELESS NETWORKS 2 Networks 1. WIRELESS NETWORKS 1.1 WiFi 802.11 3 Networks OSI Structure 4 Networks Infrastructure Networks BSS : Basic Set Service ESS : Extended
A Study on Delay, Throughput and Traffic Measurement for Wi-Fi Connected Stations Based on MAC Sublayer
Original Article A Study on Delay, Throughput and Traffic Measurement for Wi-Fi Connected Stations Based on MAC Sublayer Md. Abbas Ali Khan* 1, Khalid Been Md. Badruzzaman Biplob 2 Rahman 3 and Md. Sadekur
Analyzing the Impact of DCF and PCF on WLAN Network Standards a, b and g
Analyzing the Impact of DCF and PCF on WLAN Network Standards 802.11a, 802.11b and 802.11g Amandeep Singh Dhaliwal International Science Index, Computer and Information Engineering waset.org/publication/9996677
Bluetooth. Acknowledgements. Based on Jochen Schiller slides. Supporting text
BT 1 Bluetooth FEUP PR BT 2 Acknowledgements Based on Jochen chiller slides upporting text» Jochen chiller, obile Comunications, Addison-Wesley» ection 7.5 Bluetooth BT 3 Bluetooth» Universal radio interface
IEEE ah. sub 1GHz WLAN for IoT. What lies beneath Wi-Fi HaLow. Eduard Garcia-Villegas, Elena López-Aguilera Dept. of Network Engineering
by wilgengebroed IEEE 802.11ah sub 1GHz WLAN for IoT What lies beneath Wi-Fi HaLow Eduard Garcia-Villegas, Elena López-Aguilera Dept. of Network Engineering eduardg@entel.upc.edu elopez@entel.upc.edu Contents
Wireless Technologies
Wireless Technologies Networking for Home and Small Businesses Chapter 7 Manju. V. Sankar 1 Objectives Describe wireless technologies. Describe the various components and structure of a WLAN Describe wireless
Medium Access Control (MAC) Protocols for Ad hoc Wireless Networks -IV
Medium Access Control (MAC) Protocols for Ad hoc Wireless Networks -IV CS: 647 Advanced Topics in Wireless Networks Drs. Baruch Awerbuch & Amitabh Mishra Department of Computer Science Johns Hopkins University
IEEE or ETSI BRAN HIPERLAN/2: Who will win the race for a high speed wireless LAN standard?
IEEE 802.11 or ETSI BRAN HIPERLAN/2: Who will win the race for a high speed wireless LAN standard? Andreas Hettich and Matthias Schröther Communication Networks Aachen University of Technology E-Mail:
Status of P Sub-Specification
Status of P1451.5 802.11 Sub-Specification June 7, 2004 Ryon Coleman Senior Systems Engineer 802.11 Subgroup rcoleman@3eti.com Agenda 1. IEEE 802.11 Architecture 2. Scope within the 1451 Reference Model