WLAN Design & Implementation ผศ. ดร. อนันต์ ผลเพิ่ม Asst.Prof....
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Transcript of WLAN Design & Implementation ผศ. ดร. อนันต์ ผลเพิ่ม Asst.Prof....
WLAN Design & Implementation
ผศ.ดร. อนั�นัต์ ผลเพิ่��ม Asst.Prof. Anan Phonphoem, [email protected]://www.cpe.ku.ac.th/~anan
Intelligent Wireless Network Group (IWING Lab) http://iwing.cpe.ku.ac.thComputer Engineering DepartmentKasetsart University, Bangkok, Thailand
KMITNB Jan 29, 2004
IWING LAB; Computer Engineering Department; Kasetsart University2
Outline
WLAN TechnologyConceptual Review
– WLAN Configuration– Management
PlanningDesign & Implementation Phase
IWING LAB; Computer Engineering Department; Kasetsart University3
Wireless System Path
Source: Mobile Communications International
IWING LAB; Computer Engineering Department; Kasetsart University4
Wireless Classification
WAN
WAN-MAN
MAN
Pico-Cell
MAN-LAN
PAN
LAN-PAN
0km~50km ~2km ~10m
Personal Operating Space
Courtesy of IEEE 802.15, Jan. 2001
WPANBluetooth
WLANIEEE802.11HyperLan
WWANGSM/ GPRS /
CDMA
WMANIEEE802.16
IWING LAB; Computer Engineering Department; Kasetsart University5
History and present of IEEE 802.11
IWING LAB; Computer Engineering Department; Kasetsart University6
IEEE 802.11 Family
Standards Band (GHz) Raw Throughput
802.11 2.4 2Mbps (Legacy)
802.11a 5 54Mbps
802.11b 2.4 11Mbps
802.11g 2.4 54Mbps
802.11n ?? 100 Mbps
IWING LAB; Computer Engineering Department; Kasetsart University7
IEEE 802.11 Family
Standards Descriptions
802.11c Improves interoperability
802.11d Multiple Regulatory Domains (Improve Roaming; New country)
802.11e Quality of Service (QoS); prioritizing voice or video
802.11f Inter-Access Point Protocol (IAPP)
802.11h Supports measuring and managing the 5-GHz radio signals in 802.11a
802.11i Enhanced Security (repairs WEP weakness)
802.11j Extensions for Japan
802.11k Passing specific radio frequency health and management data to higher-level management apps.
IWING LAB; Computer Engineering Department; Kasetsart University8
History: 802.11 Legacy
1997: First standard– Standard name: IEEE 802.11-1997– Updated: IEEE 802.11-1999 – Starting Point for “Standard-based WLAN”
For 2 Mbps: (fallback to 1 Mbps – Noisy): Direct sequence Spread Spectrum (DSSS) modulation
For 1-2 Mbps Frequency Hopping Spread Spectrum (FHSS)
Both operate in ISM band 2.4 GHz FHSS, DSSS, and infrared medium
IWING LAB; Computer Engineering Department; Kasetsart University9
802.11b 802.11b-1999 Range 50 – 100 m. (depends on obstacles) Omnidirectial antenna Indoor / Outdoor / Point-to-point (high-gain external
antennas) Max throughput of 11 Mbit/s (5.5, 2,1 Mbps) Attenuation: Metal, Thick walls, Water, etc. ISM Band 2.4 GHz; DSSS; CSMA/CA 14 overlapping ch. (Different ch.for different countries)
– 3 simultaneously ch. (such as 1, 6, and 11) Proprietary speed extension "802.11b+" (22, 33 and 44
Mbit/s)
IWING LAB; Computer Engineering Department; Kasetsart University10
802.11a
2001 (802.11a-1999) Max throughput of 54 Mbps (Normally around 20 Mbps) ISM Band 5 GHz (FCC may open more spectrum) 12 nonoverlapping channels,
– 8 dedicated to indoor– 4 to point to point
Not widely deployed (US. / Japan)– 802.11b popularity– Less range / More attenuation– Lack of roll back compatibility (now support a,b,and g)– In Europe considering HiperLan2
IWING LAB; Computer Engineering Department; Kasetsart University11
802.11g
3rd quarter 2003 ISM Band 2.4 GHz Max throughput of 54 Mbps (Net 24.7 Mbps) Fully backwards compatible with 802.11b Dual-band / Tri-mode
– supporting a, b, and g– A single wireless card / Access point
IWING LAB; Computer Engineering Department; Kasetsart University12
802.11 Wi-Fi
Specification defined by IEEE (not Compatibity guarantee)
A special group, Wi-Fi Alliance– Group of maufacturer– Test compatibility– Guarantees interoperability (by issue Wi-Fi
Trademark)– Start with 802.11b Dual band/Tri mode (a, b, or g)– Security standard Wi-Fi Protected Access (WPA)
IWING LAB; Computer Engineering Department; Kasetsart University13
Wireless Hot Spot
Public places – Top-rated hotels and restaurants – Colleges / Universities
In-building antenna systems to support various wireless technologies (Wi-Fi/cellular)
Wireless friendly environmental hot spot– KUWiN (Kasetsart University Wireless
Network http://kuwin.ku.ac.th) http://www.wi-fihotspotlist.com/
WLAN Review
IWING LAB; Computer Engineering Department; Kasetsart University15
WLAN Category
Wireless LANs (WLAN)– Radio Waves– Infrared Light– Carrier currents (“no new wire”)
Wireless Point-to-Point NetworksWireless WANs
IWING LAB; Computer Engineering Department; Kasetsart University16
Radio Based Wireless LANs
Advantages– No line of sights– Propagate through obstacles
Disadvantages– Interference– Security
IWING LAB; Computer Engineering Department; Kasetsart University17
WLAN Goal
Compliment wired LANs (or replace in the near future?)
Two main reasons– Increase user mobility &
productivity– Increase installation flexibility in
difficult cabling situations
IWING LAB; Computer Engineering Department; Kasetsart University18
WLAN Questions
Throughput ? Scalability ? Performance ? Best technologies ?Application support ?
– client-server / Network programs– Quality-of-service
IWING LAB; Computer Engineering Department; Kasetsart University19
Data rates and Range
Source: Proxim
IWING LAB; Computer Engineering Department; Kasetsart University20
WLAN Configurations
Independent WLANInfrastructure WLAN
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Independent WLAN
Ad HocSimplestRapid deploymentPeer-to-peerNo administration
IWING LAB; Computer Engineering Department; Kasetsart University22
Independent WLAN
Single Cell Multiple Cells
IWING LAB; Computer Engineering Department; Kasetsart University23
Independent WLAN
Can extended range by using an Access Point (acting as a repeater)
2d
IWING LAB; Computer Engineering Department; Kasetsart University24
Infrastructure WLAN
Need an Access PointConnect to the wired
LANNeed InfrastructureNeed administration
IWING LAB; Computer Engineering Department; Kasetsart University25
Infrastructure WLAN
IWING LAB; Computer Engineering Department; Kasetsart University26
Infrastructure WLAN
IWING LAB; Computer Engineering Department; Kasetsart University27
SOHO Infrastructure WLAN
Hub/Switch
ComputerServer
Access Point
Printer
IWING LAB; Computer Engineering Department; Kasetsart University28
(Large) Infrastructure WLAN
Router
Internet
Hub/Switch
LAN
Hub/Switch
LAN
IWING LAB; Computer Engineering Department; Kasetsart University29
Simple WLAN Management
Router
Internet
Hub/Switch
LAN
Hub/Switch
LAN
IWING LAB; Computer Engineering Department; Kasetsart University30
VLAN Switch Management
Router
Internet
VLAN Switch VLAN Switch
LAN
LAN
IWING LAB; Computer Engineering Department; Kasetsart University31
AP with VLAN Capability
Router
Internet
Hub/Switch
LAN
Hub/Switch
LAN
IWING LAB; Computer Engineering Department; Kasetsart University32
Mobile IP
Router
Internet
LAN
IWING LAB; Computer Engineering Department; Kasetsart University33
Mobile IP
Router
Internet
LAN
Home Agent
Foreign Agent
WLAN Planning
IWING LAB; Computer Engineering Department; Kasetsart University35
Design Requirements
To Keep in mind– Availability– Scalability– Manageability– Interoperability
IWING LAB; Computer Engineering Department; Kasetsart University36
Planning
Set Project Management PrinciplesPlanning a projectExecuting the project
IWING LAB; Computer Engineering Department; Kasetsart University37
Set Project Management Principles
Clear goal / activities / communications
Reduction of risksOn time / within budget
IWING LAB; Computer Engineering Department; Kasetsart University38
Cost of Ownership
Infrastructure costsClient device costsMonthly costs (Power & Internet Access)Management costs
– Training– Downtime costs– Support costs (Troubleshoot + repair)
IWING LAB; Computer Engineering Department; Kasetsart University39
Planning a project
Define the project scope Develop a work plan / schedule Identify resources (team/materials) Develop a budget
(labor/HW/SW/management) Define project operations (role/standard) Evaluation risks (cause of risks adjust)
IWING LAB; Computer Engineering Department; Kasetsart University40
Executing the project
Kick-off meeting (review project plan)Status checkTechnical meetingProgress report
IWING LAB; Computer Engineering Department; Kasetsart University41
Define WLAN requirements
User profile & interface
Functional (expected)
Application Information Flow Performance
(Reliability/Availability/BW/Delay)
System Interface Environmental Department support Regulation (RF) Mobility Security Budget Schedule
Design & Implementation Phase
IWING LAB; Computer Engineering Department; Kasetsart University43
Implementing a WLAN
Design a WLANPrepare for operational support Installation
Design a WLAN
IWING LAB; Computer Engineering Department; Kasetsart University44
Design & Implementation Cycle
Source: Cisco Networking Academy
IWING LAB; Computer Engineering Department; Kasetsart University45
Design Phase
Define network elementsSelect productsSite surveyVerify the designDocument the designProcure components
IWING LAB; Computer Engineering Department; Kasetsart University46
Defining Network Elements
Identify the network elements– SW (Application / Communication)– OS– LAN /WAN (media / backbone)– Wireless connection (media / data rate)– Addressing– Network management
Determining requirements– Choose standard (mature) technologies
IWING LAB; Computer Engineering Department; Kasetsart University47
Selecting Products
FunctionalityAvailabilitySupportPriceStandard compliance
IWING LAB; Computer Engineering Department; Kasetsart University48
Site Survey
Determine coverage area (Cell)Determine number of cells neededDetermine the Access Point
location
IWING LAB; Computer Engineering Department; Kasetsart University49
Environmental Consideration
Environment characteristics– Completed Open (empty floor, no desk)– Semi-Open (partitioning area)– Closed (Blocked room, high wall)
Barriers– RF penetration– Attenuations
IWING LAB; Computer Engineering Department; Kasetsart University50
RF Barriers
RF Barrier Attenuation Example
Air minimum
Wood Low Partitions
Plaster Low Office partitions
Synthetic Material Low Office patitions
Glass Low Windows
Water Medium Damp wood, aquarium
Bricks Medium Walls
Marble Medium Walls
Paper High Paper rolls
Concrete High Floors / Walls
Metal Very High Desk / partitions / elevator
IWING LAB; Computer Engineering Department; Kasetsart University51
Conducting Site Survey
Preparation PhaseExecution PhasePost survey Phase
IWING LAB; Computer Engineering Department; Kasetsart University52
Preparation Phase
Contact the authorized person Blueprint / Floor planAccess point / notebook / wireless cardPower cord extension / Walkie-Talkie
IWING LAB; Computer Engineering Department; Kasetsart University53
Execution Phase
Verify the blueprintMark permanent user locationsMark permanent roaming area Identify obstacles / interference sources Identify preliminary of APTest and Record signal strength of
selected locationsAdjust AP location
IWING LAB; Computer Engineering Department; Kasetsart University54
Post Survey Phase
Documentation– Summarize the updated floor plan– Summarize locations of AP– Summarize / Draw the coverage area– Note on restrictions and sugestions
IWING LAB; Computer Engineering Department; Kasetsart University55
Example
WC
WC
Lecture Room 1
Lecture Room 2
ComputerRoom
Lab
ControlRoom
Elv1
Elv2
Commonroom
IWING LAB; Computer Engineering Department; Kasetsart University56
Example
WC
WC
Lecture Room 1
Lecture Room 2
ComputerRoom
Lab
ControlRoom
Elv1
Elv2
Commonroom
A
B
C
D
1
2
34
5
6
8 9
10
11
12
7
IWING LAB; Computer Engineering Department; Kasetsart University57
Signal Status
IWING LAB; Computer Engineering Department; Kasetsart University58
Example
AP Pos Com. Quality Note
A 1
2
6
B 1
2
3
4
5
C 6
7
8
9
10
IWING LAB; Computer Engineering Department; Kasetsart University59
Example
AP Pos Com. Quality Note
A 1 Poor
2 V.good
6 Fair
B 1 Poor
2 Poor
3 Good
4 V.good
5 Poor
C 6 Poor
7 Poor Near microwave oven
8 Poor
9 Good
10 V.Good
IWING LAB; Computer Engineering Department; Kasetsart University60
Design Phase
Define network elementsSelect productsSite surveyVerify the designDocument the designProcure components
IWING LAB; Computer Engineering Department; Kasetsart University61
Implementing a WLAN
Design a WLANPrepare for operational support
– Training / Helpdesk– Admin / network monitoring
Installation
IWING LAB; Computer Engineering Department; Kasetsart University62
Implementing a WLAN
Design a WLANPrepare for operational supportInstallation
– Storage– HW Installation / power outlet– network connection point / wiring– testing
IWING LAB; Computer Engineering Department; Kasetsart University63
Summary
Clear Design GoalsGet support from all levelsWell planAwareness DesignCaution about the implementationDocumentation
IWING LAB; Computer Engineering Department; Kasetsart University64
References
WLAN course material, Anan Phonphoem, Computer Engineering, Kasetsart University, 2001
Guide to Designing and Implementing Wireless LANs, Mark Ciampa, Course Technology – Thomsom Learning, 2001, ISBN 0-619-03494-7
Wireless LANs: Implementing Interoperable Networks, Jim Geier, MTP, 1999, ISBN 1-57870-081-7
Principles of Wireless Networks, Kaveh Pahlavan & Prashant Krishnamurthy, Prentice Hall, 2002, ISBN 0-13-093003-2
IEEE 802.11 Standard (www.ieee.org) Wireless LAN Association (www.wlana.org) Wireless LAN Alliance (www.wlana.com)