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Wireless LAN Solution & Deployment Tjie Seng, Njauw. Fixed Communications. Mobile Communications. The Paradigm Shift. Fixed Work Area. Work where you want!. The Paradigm Shift. Tethered Network Connection. Wireless Network Connectivity Wireless LAN Products. The Paradigm Shift. - PowerPoint PPT Presentation
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1© 2000, Cisco Systems, Inc.
Wireless LAN Solution & Deployment
Tjie Seng, Njauw
2© 2000, Cisco Systems, Inc.
The Paradigm ShiftThe Paradigm Shift
Fixed Communications
Mobile Communications
3© 2000, Cisco Systems, Inc.
The Paradigm ShiftThe Paradigm Shift
Fixed Work Area
Work where you want!
4© 2000, Cisco Systems, Inc.
The Paradigm ShiftThe Paradigm Shift
Tethered NetworkConnection
Wireless Network ConnectivityWireless LAN Products
5© 2000, Cisco Systems, Inc.
Radio Frequency Technologies WLANs Product Categories Standards Based Technology
What is a Wireless LAN?
6© 2000, Cisco Systems, Inc.
Radio Frequency TechnologiesRadio Frequency Technologies
Wireless DataNetworks
Broadband PCSBroadband PCSMetricomMetricom
Local WideCoverage Area
SatelliteSatellite
Spread SpectrumWireless
LANs
Spread SpectrumWireless
LANs
Circuit & Packet DataCellular, CDPD, RAM, ARDIS
Circuit & Packet DataCellular, CDPD, RAM, ARDIS
Narrowband PCSNarrowband PCS
InfraredWireless
LANs
InfraredWireless
LANs
Narrow BandWireless LANsNarrow Band
Wireless LANs
Wireless LAN 802.11b
Dat
a R
ates
9.6 Kbps
19.6 Kbps
56 Kbps
1 Mbps
2 Mbps
4 Mbps
10 Mbps
7© 2000, Cisco Systems, Inc.
License Free ISM BandLicense Free ISM Band
ExtremelyLow
VeryLow
Low Medium High VeryHigh
UltraHigh
SuperHigh
Infrared VisibleLight
Ultra-violet
X-Rays
AudioAM Broadcast
Short Wave Radio FM BroadcastTelevision Infrared wireless LAN
Cellular (840MHz)NPCS (1.9GHz)
902-928 MHz26 MHz
Older Product
5 GHz(IEEE 802.11A)
HyperLANHyperLAN2
Future Technology
2.4 – 2.4835 GHz83.5 MHz
(IEEE 802.11B)Current Product
8© 2000, Cisco Systems, Inc.
Binary phase shift keyed (BPSK) • BPSK uses one phase to represent a binary 1 and another
to represent a binary 0 for a total of two bits of binary data. This is utilized to transmit data at 1Mbps.
Quadrature phase shift keying (QPSK). • With QPSK, the carrier undergoes four changes in phase
and can thus represent four binary bits of data. This is utilized to transmit data at 2 Mbps.
Complementary code keying (CCK) • CCK uses a complex set of functions known as
complementary codes to send more data.• One of the advantages of CCK over similar modulation
techniques is that it suffers less from multipath distortion. This is utilized to transmit data at 5.5 and 11Mbps.
Radio ModulationRadio Modulation
9© 2000, Cisco Systems, Inc.
2 Mbps DSSS350 feet radius
In Building WLANsIn Building WLANs
5.5 Mbps DSSS 175 feet radius
11 Mbps DSSS 100 feet radius
Average 802.11bAccess Point Range
10© 2000, Cisco Systems, Inc.
Direct Sequence ModulationDirect Sequence Modulation
• Each data bit becomes a string of chips (chipping sequence) transmitted in parallel across a wide frequency range
• Minimum chip rate per the FCC is 10 chips for 1 and 2MB (BPSK/QPSK) and 8 chips for 11Mb (CCK) data rates.
If the data bit was: 1001
Chipping code is : 1=00110011011 0=11001100100
Transmitted data would be:
00110011011 11001100100 11001100100 00110011011
1 0 0 1
11© 2000, Cisco Systems, Inc.
Channels- 802.11 DSChannels- 802.11 DS
• (11) 22 MHz wide stationary channels• x “chips per bit”, means each bit sent redundantly• 11 Mbps data rate• 3 non-overlapping channels• 3 Access Points can occupy same area
1 2 3 4 5 6 7 8 9 10 112400
2472241212 13
12© 2000, Cisco Systems, Inc.
Scalability With Direct SequenceScalability With Direct Sequence
Blue= 11Mb
Green=11Mb
Red=11Mb
Total Bandwidth=33MB!!!
13© 2000, Cisco Systems, Inc.
Wireless Capacity per Cell
0
5
10
15
20
25
30
35
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31
Number of Access Points
Mbp
s C
apac
ity
DS-2Mb
DS-11Mb
ScalabilityScalability
14© 2000, Cisco Systems, Inc.
Power Level & Cell SizePower Level & Cell Size
15© 2000, Cisco Systems, Inc.
In-Building Design ConsiderationsIn-Building Design Considerations
• 200 Users on the Floor• Reduce Power - 5mW• 18 Access Points• 11 Users per AP of
shared bandwidth
1
6
11
1
11 6
6
11
1
1
6
11
1
11
6
6
11
1
• 200 Users on the Floor• Full Antenna Power –
30mW• Max 3 Access Points• 67 Users per AP of
shared bandwidth
1 6 11
16© 2000, Cisco Systems, Inc.
WLAN Product CategoriesWLAN Product Categories
In-Building WLANs
Building-to-Building WLANS
17© 2000, Cisco Systems, Inc.
In-Building WLANIn-Building WLANComponentsComponents
Internet
Ethernet Backbone
18© 2000, Cisco Systems, Inc.
In-Building WLANIn-Building WLANComponentsComponents
Internet
Ethernet Backbone
Overlapping “cells” Overlapping “cells” Allow for RoamingAllow for Roaming
19© 2000, Cisco Systems, Inc.
In-Building WLANIn-Building WLANComponentsComponents
Internet
Ethernet Backbone
20© 2000, Cisco Systems, Inc.
In-Building WLANIn-Building WLANComponentsComponents
Internet
Ethernet Backbone
21© 2000, Cisco Systems, Inc.
Inline Power Inline Power
Source operating current from the Ethernet port, over the Cat 5 cable. Line power configuration is compliant with all of Cisco’s line power
enabled devices such as switches and line power patch panels. Distances up to 100 meters
Call Manager Server
VoIP Phone
AP Switch
Powered CAT5
22© 2000, Cisco Systems, Inc.
Load BalancingLoad Balancing
• AP’s configured for load sharing use different RF channels in coverage area
• Policy can be based on number of users, bit error rate, or signal strength
Channel 1
Channel 6
23© 2000, Cisco Systems, Inc.
Hot StandbyHot Standby
• AP’s co-located for hot standby use SAME RF channel in coverage area
• Standby AP acts as probe for monitoring and management
Active StandbyChannel X
Channel X
24© 2000, Cisco Systems, Inc.
Security ConsiderationsSecurity Considerations
(*#&$(*#&$*( #(*&
$*(#$#)($__%#
#$#%
40-Bit128-Bit
Encryption or WEP
25© 2000, Cisco Systems, Inc.
Centralized User-Based Centralized User-Based AuthenticationAuthentication
AuthenticatorAuthenticator(e.g. Access (e.g. Access
Point, Catalyst Point, Catalyst Switch(?))Switch(?))SupplicantSupplicant
Semi-Public Semi-Public Network /Network /Enterprise EdgeEnterprise Edge
AuthenticationAuthenticationServerServer
RADIUS
EAP Over Wireless/LAN
EAP Over Wireless/LAN
(EAPOW/EAPOL)
(EAPOW/EAPOL)
EAP Over EAP Over
RADIUSRADIUS
Extended Enterprise(Branch Office, Home, etc.)
EnterpriseIntranet
26© 2000, Cisco Systems, Inc.
ManageabilityManageabilitySite Survey
Signal Strength
Signal Quality
•Diagnostic Utilities •Simple and Graphical •Minimizes Helpdesk Calls
27© 2000, Cisco Systems, Inc.
In Building Site SurveyIn Building Site Survey
28© 2000, Cisco Systems, Inc.
•Decreases Implementation Costs A Fraction the Cost of Trenching
•High Speed ConnectionsGreater Bandwidth than T1 Lines
•Eliminates Recurring ChargesNo Monthly Leased Line Fees
•Reduces Installation DelaysNo Right of Way or Permits Required, Installation in an Afternoon
•Makes Physical Barriers IrrelevantBypass Lakes, Rivers, Freeways, Railroads
Wireless BridgesWireless Bridges
29© 2000, Cisco Systems, Inc.
Wireless AntennasWireless AntennasBridgesBridges
Patch Wall Mast MountHigh Gain
Mast Mount Yagi Mast Solid Dish
Type
Gain
ApproximateRange at 2 Mbps
ApproximateRange at 11 Mbps
Cable Length
Directional
Beam Width
8 dBi
60 H55 V
2.0 Miles
3390’
3’
Omni
5.2 dBi
360 H75 V
5000’
1580’
3’
Omni
12 dBi
360 H7 V
4.6 Miles
1.4 Miles
1’
Directional
13.5 dBi
6.5 Miles
2 Miles
1.5’
30 H25 V
Directional
21 dBi
25 Miles
11.5 Miles
2’
12.4 H12.4 V
30© 2000, Cisco Systems, Inc.
0 to 25 miles(line of sight)
Ethernet
Bridge
OptionalAntenna
Building A Building B
OptionalAntenna
Point-to-Point ConfigurationPoint-to-Point Configuration
31© 2000, Cisco Systems, Inc.
Bridge
Bridge
PCI Card
MC Hub
Bridge-Bridge, Bridge-ClientBridge-Bridge, Bridge-Client
32© 2000, Cisco Systems, Inc.
Outdoor Path ConsiderationsOutdoor Path Considerations
• Radio line of sight• Earth bulge• Fresnel Zone• Antenna and cabling• Data rate
33© 2000, Cisco Systems, Inc.
Bridge Application: Bridge Application: Wireless Campus linkWireless Campus link
U N I V E R S I T YU N I V E R S I T Y
Channel #11
Channel #6
Channel #1
34© 2000, Cisco Systems, Inc.
IEEE 802.11 IEEE 802.11 A Move Toward Standardization!A Move Toward Standardization!
• A very high-performance WLAN system Efficient MAC and high-quality radio802.11 products perform better thanproprietary systems
Client interoperability • WEP standard privacy and authentication• Standards-based migration path for system
growth• The IEEE 802.11 (July 1997) for 1 and 2Mb
DSSS• The IEEE802.11b (Sept 1999) for 11Mb DSSS
35© 2000, Cisco Systems, Inc.
WI-FI CertificationWI-FI Certification
• WECA certifies Interoperability between products.
• This provides assurance to customers of migration and integration options.
• Certified products can be found at http://www.wirelessethernet.org/
36© 2000, Cisco Systems, Inc.
Soo… What’s Next..Soo… What’s Next..
37© 2000, Cisco Systems, Inc.
Internet Mobile OfficeInternet Mobile Office• Broadband solution for the mobile business
professional that combines all of the following:
Wired and wireless connectivity Broadband speeds when on the moveAccess to critical business applicationsSecure, end-to-end VPN accessNationwide and international coverageConsolidated billing across service providersAccess to localized content
38© 2000, Cisco Systems, Inc.
TownTownClubsClubs
Airline LoungesAirline Airline
LoungesLounges
HotelsHotelsHotels
Other PublicVenues
Other PublicOther PublicVenuesVenues
ConventionCenters
ConventionConventionCentersCenters
CafesCafesCafes
AirportsAirports
CommercialBuildings
CommercialCommercialBuildingsBuildings
TownTownClubsClubs
Airline LoungesAirline Airline
LoungesLounges
HotelsHotelsHotels
Other PublicVenues
Other PublicOther PublicVenuesVenues
ConventionCenters
ConventionConventionCentersCenters
CafesCafesCafes
AirportsAirports
CommercialBuildings
CommercialCommercialBuildingsBuildings
Bringing Mobile Offices to Mobile Bringing Mobile Offices to Mobile ProfessionalsProfessionals
Enterprise
Customers
39© 2000, Cisco Systems, Inc.
Wireless Mobile Business Professionals Public Spaces
InternetT1/T3
Enterprise Network
T1/T3Airport / Public Spaces
Switch
Router
FirewallVPN
Concentrator
Service Subscriber Gateway
Settlement SystemServer
HotelsT1/T3
Wireless 802.11b Access Point
Wireless 802.11b Clients w/ VPN Client
Service Subscriber Gateway
Switch
T1/T3
Wireless 802.11b Access Point