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Kent Lundgren next level solutionsvg136b7
Wi-Fi Technology
NCC Workshop, 2003Kent Lundgren
Wi-Fi Technology
NCC Workshop, 2003Kent Lundgren
Kent Lundgren next level solutions Apr 10, 2023
2
Outline
• Introduction and Scope• Wi-Fi Protocols• Wi-Fi vs. Bluetooth• Wi-Fi vs. Cellular• Hotspot Drivers• Hotspot Players• Backhaul• WISPs• Wi-WAN Solution• Conclusions
Kent Lundgren next level solutions Apr 10, 2023
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Wi-Fi Introduction
• Simple, cheap and ubiquitous• Great solution for
– Home LAN– Office LAN– Periodic Event LAN, conferences, trade shows
• When applied to a large area Internet service business, challenges arise:– Access Points get very large in number.– Build-out, Management & Maintenance become
exponentially complex. – Internet Access operating cost dwarfs equipment cost.
Kent Lundgren next level solutions Apr 10, 2023
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Wi-Fi Market Size
The Analysys Group, 2002; Europe 2007 is Harris Estimate
0.0
10.0
20.0
30.0
40.0
2002 2003 2004 2005 2006 2007
Users growing from 600K to 21.5M in US
Revenue growing from $134M to $3B in US
U.S.
Europe
Strong User Base Translates into Strong Revenue Growth
Number of Users (millions)
Revenue ($ millions)
Kent Lundgren next level solutions Apr 10, 2023
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802.11 (Wi-Fi) Protocol Comparison802.11 802.11b 802.11g
(draft)802.11a
Standard Approved July 1997 Sept 1999 Still in Development
Sept 1999
Available Spectrum 83.5MHz 83.5MHz 83.5MHz 580MHz
Frequency of Operation 2.400-2.483GHz
2.400-2.483GHz
2.400-2.483GHz
5.150-5.350GHz
5.470-5.850GHz
Non-Overlapping Channels
3 3 3 4+ (Asia)
13 (US)
19 (Europe)
Modulation Technology FHSS
DSSS
CCK CCK,
OFDM
OFDM
Data Rate per Channel 1, 2 5.5, 11 6, 9, 12, 18,24, 36, 48, 54
6, 9, 12, 18,24, 36, 48, 54
Max UDP Throughput(1500 byte)
1.7 Mbps 7.1 Mbps 19.5 Mbps 29.2 Mbps
Max TCP/IP Throughput (1500 byte)
1.6 Mbps 5.9 Mbps 14.4 Mbps 24.4 Mbps
802.11i = temporal key integrity protocol – may replace WEP 802.11x = authentication protocol
Kent Lundgren next level solutions Apr 10, 2023
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Pluses & Minuses+ -
802.11b • Accepted Wi-Fi Standard • Millions of devices (lowest price)• Laptops shipping with Wi-Fi WLAN cards inside• Cell phones shipping with .11b devices inside
• Limited to 7.1 Mbps • Microwave ovens and cordless phones operate on 2.4 GHz• Straight 802.11b not suited outdoors primary due to hidden node issues • Only 3 co-located channels
802.11a • High speed (29.2 Mbps)• Less crowded 5 GHz radio channels• Good for Office WLANs• Since it is OFDM, it has good multi-path tolerance for reflections found in almost all indoor installations.
• Range and wall penetration not as good as 2.4 GHz frequencies• Only get higher thru-put when very close to AP• Receiver sensitivity much worse than .11b; less TX power•Cordless Phone use of this band is growing• Not good for outdoors unless modified
802.11g •High speed (19.5 Mbps)• Talks to both .11g and .11b devices in the same wireless network• Greater indoor range and wall penetration than .11a devices
• When 11b devices are present in g/b mode, thru-put suffers • Only 3 co-located channels (same for .11b)• Microwave ovens, cordless phones, TV cameras, baby monitors, etc operate on 2.4 GHz• Not suitable for outdoors
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• Do not use home-brewed 802.11a/b/g systems outdoors. Expect severe interference from those who do at 2.4 GHz.
• 802.11a’s biggest advantage, generous spectral allocation (in the US), outweighs its disadvantages.
Recommendations
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Different Markets & Roles
high power & long range
medium power & medium range
low power & short range
WPAN• BT• HomeRF
IEEE 802.11
GSM, CDMA, GPRS, etc.
x0M
x00MxKM
• Bluetooth– Designed for quick, seamless,
short-range networks– Features low power
consumption, small protocol stack,robust data & voice transfer
– Cheap price– Good choice for WPAN
(Wireless Personal Area Networks)
• 802.11– Designed for infrequent mobility,
IP-based data transmission– Medium range and high data
rate– At least 10x the price of
bluetooth– Good choice for WLAN
Kent Lundgren next level solutions Apr 10, 2023
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Wi-Fi vs. Cellular
• Cellular comes from the Telecom World– Slow standardization and long product lifecycle (decades)
• Circuit switched• Trunk lines and exchanges are digital TDM
– 2.5G/3G data networks are hybrid approaches• Circuit-switched voice• Packet data
• Wi-Fi comes from the Networking World– Rapid product life cycles – Internet is the backbone, with a wireless edge
• IP from the core to the edge• Contention-based MAC lowers client cost
– IP is the dominant networking standard, while FDDI, Token Ring, Frame Relay, ATM have had limited impact
Kent Lundgren next level solutions Apr 10, 2023
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Wi-Fi & Cellular: Voice and Data
11Fait accompli. 2nd
generation cellular voice systems have very successfully
deployed since the mid-1990s.
44Emerging, but carriers
in poor financial health, 3G handsets expensive and bulky,
demand unclear.
33Emerging. Initial
applications likely in enterprise and industry
verticals.
22In progress. WLAN
deployments increasing at 50-70%
CAGR for the next few years.
2.5/3G
802.11
Cellular
WLAN
Voice Data
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Hot Spot Drivers
• Wi-Fi CPE is [will be] “free”– Integrated into next generation PCs and PDAs– Very different from other access solutions– Access business cases normally very sensitive to CPE costs
• Mobility/Portability is a “killer” application in itself…we learned that from voice
• Early adopters are business users– They can pay– They have no other roaming “data communications “ options
• Except “3G”…. but what and where is it?– “Killer” application is remote corporate LAN access
• Adoption of 802.11a– Big speed jump, lots more spectrum
Kent Lundgren next level solutions Apr 10, 2023
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Anticipated Wi-Fi Deployment
• Phase 1 - Early deployments, isolated sites• Airports, the odd hotel, convention halls• low user density & low speed user access rates
(primarily 802.11b)
• Phase 2 - Full deployments: network build-outs, coverage driven
• Consolidations to gain coverage and broader service portfolios, fixed and mobile carriers get involved– Dependable coverage and availability– Advanced roaming services & agreements– Stable, predictable pricing
Kent Lundgren next level solutions Apr 10, 2023
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WISP WISP Hotspot OperatorHotspot Operator
AAA / RADIUS Proxy Server
VPN / AAAServer
Roaming RADIUS NETwork Server
Optional Roaming Intermediary
Broker or Settlement Services
Global Roaming AAAServices Network
Home Entity Home Entity (such as User’s Corporation (such as User’s Corporation
or Service Provider)or Service Provider)
AAA ROAMing
Server
Central Policy / Authentication
Database
Mobile / Nomadic User
AgreementAgreementAgreementAgreement
Home Entities: • Definition: “who the Mobile / Nomadic
User has a billing relationship and account with (may not be a Wireless Hot Spot Operator)”
• Examples are: Corporations, Carriers, and WISPs Themselves
HotspotsHotspots
• Maintain security association with their nomadic user (Authentication, Authorization, and Accounting)
• Additional roaming revenues from users
without having to deploy WLAN infrastructure
Hot Spot Players
Kent Lundgren next level solutions Apr 10, 2023
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WISP WISP Hotspot OperatorHotspot Operator
AAA / RADIUS Proxy Server
VPN / AAAServer
Roaming RADIUS NETwork Server
Optional Roaming Intermediary
Broker or Settlement/Clearinghouse
Global Roaming AAAServices Network
Home Entity Home Entity (such as User’s Corporation (such as User’s Corporation
or Service Provider)or Service Provider)
AAA ROAMing
Server
Central Policy / Authentication
Database
Mobile / Nomadic User
AgreementAgreementAgreementAgreement
Roaming Intermediaries:• Definition: “participate in the Authentication and
Accounting Process between multiple Hotspot Operators and various Home Entities”
• Examples are: Remote Access (dialup) Providersand Settlement (cellular) Carriers/Providers
HotspotsHotspots
• Provides Home Entities with aggregated WLAN secure hotspot locations for their users
• Provides WISP Hotspot Operators with aggregated customer base of already provisioned nomadic users
Hot Spot Players, con’t.
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WISP WISP Hotspot OperatorHotspot Operator
AAA / RADIUS Proxy Server
VPN / AAAServer
Roaming RADIUS NETwork Server
Optional Roaming Intermediary
Broker or Settlement Services
Global Roaming AAAServices Network
Home Entity Home Entity (such as User’s Corporation (such as User’s Corporation
or Service Provider)or Service Provider)
AAA ROAMing
Server
Central Policy / Authentication
Database
Mobile / Nomadic User
AgreementAgreementAgreementAgreement
WISP Hotspot Operators: • Definition: “deploys public access WLAN
networks (e.g., Wi-Fi) and public access control gateway functionality”
• Example locations: airports, restaurants, hotel rooms, company lobbies, conference rooms, apartments
HotspotsHotspots
• Providing WLAN access attracts customers
• Roaming brings additional revenues without cost of customer acquisition / provisioning
• Cost sensitive infrastructure build out
Hot Spot Players, con’t.
Kent Lundgren next level solutions Apr 10, 2023
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Hotspot Operator’s Hotspot Operator’s Network Operations CenterNetwork Operations Center
AAA / RADIUS Proxy Server
Wireless Access Point
Cell 1Cell 1
Hotspot 1Hotspot 1
Wireless Access Point
Wireless Access Point
Cell 2Cell 2
Hotspot 2Hotspot 2
VPN / AAAServer
Roaming RADIUS NETwork Server
Optional Roaming Intermediary
Broker or Settlement Services
Global Roaming AAAServices Network
Home Entity Home Entity (such as User’s Corporation (such as User’s Corporation
or Service Provider)or Service Provider)
AAA ROAMing
Server
Firewall & VPN Server
Central Policy / Authentication
Database
IPSEC or PPTP VPN
NomadicUser
Login as [email protected]
BillingBilling
Roaming Roaming Revenue Revenue $ $
Cell 2Cell 2
Wireless Access Point
Cell 1Cell 1
Hot Spot Players, con’t.
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Hot Spot Challenges
• Security
• Quality of Service
• Roaming/Billing
• Revenue Model
• Backhaul
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Typical Indoor Hot Spot Configuration
.... or wireline backhaul alternative
• Traffic is not Pier-2-Pier Within the HotSpot (as is the case with LANs)
• Aside from stat-gain, all traffic in the HotSpot is Egress/Ingress through the HotSpot BackHaul Link
• No local caching or mail serving
High Speed Backhaul is required to avoid
– traffic flattening
– poor performance of VoIP, VIDoIP, etc
– poor “user experience”
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E1/DSL Backhaul (~1Mbps)
Wifi Bandwidth (~ >10Mbps)802.11a/b blend
Hot Spot Backhaul Bottleneck
Hot Spot Internet access only as good as the backhaul
Kent Lundgren next level solutions Apr 10, 2023
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Wired vs. Wireless Backhaul
• Wired bandwidth is expensive when you can get it.• Licensed wireless is less costly, reliable, more
flexible and scales well.– Supplied by emerging Wireless Wide Area Network
(Wi-WAN) operators, aka Wireless ISPs (WISPs)
Kent Lundgren next level solutions Apr 10, 2023
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Cellular Backhaul
WISP (Wi-WAN) Market Segments
E1 / Fractional E1 Business Services
Backhaul of Wi-Fi™ Hot Spots
Residential & SOHO
MTU Building Access
LE WISP Backhaul
) ) ) ) ) ) ) ) ) ) ) )
) ) ) ) ) ) ) ) ) ) ) )
) ) ) ) ) )
) ) ) ) ) )
) ) ) ) ) ) ) ) ) ) ) )
) ) ) ) ) ) ) ) ) )
) ) )
) ) )
) )
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= MB Airlink protocol
= Proprietary WWAN protocol
= WiFi protocol
IP POP
MB BASESTATION
MB REMOTESTATION
ODU / IDU
WWAN PMPREPEATER
ACCESSPOINTS
ACCESSPOINTS
WWAN BASESTATION
10,000 METERS 1,000 METERS 50 METERS
Wi-WAN Using Modified Wi-Fi Extension Outdoors
• Licensed 3.5 GHz for reliable line-of-site backhaul• Modified Wi-Fi gives WISPs: a) better reach, b) higher
throughput, and c) solution to “hidden node” problem..
Kent Lundgren next level solutions Apr 10, 2023
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Conclusions
• Higher bandwidth and generous spectral allocations (in the US) favor 802.11a.
• Standard Wi-Fi is problematic outdoors.
• Residential market is exploding now.
• Office market will grow when security is enhanced (802.11i), boosting 802.11a.
• Hotspot market will grow as roaming, billing, authentication, revenue model, and backhaul challenges are met.
• Licensed wireless is best solution for Wi-Fi backhaul.