AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 1Submission Harry Worstell, AT&T Labs
802.11-Based WirelessTechnology
to Enhance Premises Voice and Data Services
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 2Submission Harry Worstell, AT&T Labs
1996 Congress passed the Telecommunications Act, Longdistance carriers permitted local access again
1996-1999 Local exchange companies block long distancecarriers access to their lines
1998 AT&T purchased Tele-Communications Incorporated
1999 AT&T purchased Media1
AT&T to Provide Local Broadband Access
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 3Submission Harry Worstell, AT&T Labs
Rewiring the home for broadband distribution is veryexpensive and irritates customers
Now having broadband pipes to the edge of the home, it isnecessary to extend those pipes into and through the home.
With these cable acquisitions and other broadband accessmethods, AT&T anticipates being able to offer broadband
service to ~2/3 of the U.S households over the next 4 - 5 years.
Wireless is an extremely attractive solution for premisesbroadband distribution
AT&T to Provide Local Broadband Access
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 4Submission Harry Worstell, AT&T Labs
ACCESSPORT
ETHERNET
CABLE MODEM
Cable Television Headend
Hub
ETHERNET
CALL AGENT
C M T SDNS
DHCP
Eth
erne
t
To Network
CABLE MODEM
RJ11
InternetSurfing
Client Port
Customers Home
StreamingVideo
Client Port
Streaming VideoLaptop Computer
Client Port
Client Port
Client Port
Client Port
A Wireless Access Application
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 5Submission Harry Worstell, AT&T Labs
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 6Submission Harry Worstell, AT&T Labs
Data Communications Trends
Projected Volumes For Wide AreaCommunications In US By Type OfTraffic, 1994-2005
Source: IDC, AT&T Labs, GeopartnersAnalysis
Post Year 2000: “Transition from a voice focused network supporting data,to a data focused network supporting voice”
0
200
400
600
800
1000
1994 1996 1998 2000 2002 2004
Data
Voiceband - Voice, Fax & Modem
Average BandwidthGbits /Sec
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 7Submission Harry Worstell, AT&T Labs
Spanof Coverage
for ViableEconomics
ServiceInformation Rate
Demand
ServiceConcentration
Local(In-Building/
Campus)10,0001,000100101
(Miles)
1000
100
10
1
(Erlangs/Mi )
10M
1M
100K
10K
1K
(Bits/s)
2
Public(Neighborhood/
Urban)
Mobile(Suburban/Rural) Regional
Expansion of demand for wireless serviceshas caused migration of systems toward: Higher Teledensities Better Communication Quality More Throughput/User
2000+
1990's
1980's
1970's
Wireless Service Trends
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 8Submission Harry Worstell, AT&T Labs
Phase I(1997)
Phase III(2000+)
Phase II(1998)
Unified Broadband Wireless Access
Burstiness
Isochronous(Continuous Transmission,
Constant Low Delay)
Asynchronous(Bursty Transmission,
Load-Dependent, VariableDelay )
Max
imu
m T
hro
ug
hp
ut
(Mb
/sec
)
.1
1
10
100
0 .5.01
Wireless Local LoopFree-Space Optics
1
W-A
TM
IPv6
Phase 0(Pre-1997)Cellular
W-ISDN
V.3
2W
-ISD
N
PR
OTO
CO
LS
CDPD
H/S W-LAN
PR
OTO
CO
LS
TCP
/IPv4
UD
P
W-LAN
MultimediaSatellite
Future Multimedia / Wireless Technology Convergence
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 9Submission Harry Worstell, AT&T Labs
Transport Networksand Interfaces
HumanInterfaces
AccessMediation
VHF/UHF/MicrowaveRadio Subsystems
DigitalProcessing
EnergySystems
Antennas
Semiconductor& Freq ControlDevices
Unified Broadband Communications
Accommodation of RF BehaviorCellular Reuse ArchitecturesEarly Cellular/Cordless, T/R Phones
Management of RF Behavior,Separate System SolutionsAnalog Cellular/Cordless, ISDN
Adaptation to RF Environment,Merged Public/ PrivateMulti-Mode Systems,, EthernetDigital Cellular/ Wireless LANs
(1979-1985)
1986-1992
(1993-1997)
Packet ProtocolsIntegration of Wireless//Wired Services, MultimediaMulti-Access Terminals
(1998-2002)
(2003-2008)Unified Modulation,Coding, Formats
Service-TransparencyWired/Wiireless
AdvancedCoding
Unified Broadband Communications for outdoor and indoor use is a fusion of key technologies---Some are developing, others emerging...
The maturity of the various technologies dictates intermediate solutions whose capabilities satisfy the user service value judgment (cost, utility) at a particular point in time.
Technology “Superhighway On-Ramps” for Communications Networks
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 10Submission Harry Worstell, AT&T Labs
1 3
5
7
6
9
0
2
8
Multifunctional Communicators
4
* #
Rcl Sto Clr
Pwr Vol End
Graph 1
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Wireless =Central Theme
Wireless = Part of
Service "Bundle"
Handset +
Radio
Handset +
Modem +
Messaging Pager +
Conferencing Tool +
Computer +
Data Bank +
Remote Control +
Radio
New system environments and service demands have spurredfundamental architectural and technological progress:
Wireless “Y2K” Megatrends
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 11Submission Harry Worstell, AT&T Labs
Voice
Data
Distinct Media Typesw/Special Wireless Coding
ComputerData
NetworkAddressing
Video
ImageMultimedia SourceCoding Same asWired Network
Wired-Network Compatible Source Coding
New system environments and service demands have spurredfundamental architectural and technological progress:
Wireless “Y2K” Megatrends
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 12Submission Harry Worstell, AT&T Labs
New system environments and service demands have spurredfundamental architectural and technological progress:
Wireless “Y2K” Megatrends
DataData In = Data Out,Improved Error Control
Data
Data
InterferenceNoise
Blocking
Data
Wireless Connections Equivalent to Wired
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 13Submission Harry Worstell, AT&T Labs
New system environments and service demands have spurredfundamental architectural and technological progress:
Wireless “Y2K” Megatrends
Narrow Voice-RateData Pipe
More Bits/Hz
in Multipath
Environment
Higher Radio Frequencies,
Wider Channel BW
Wide
All-Purpose
Pipe
Wide-Bandwidth Wireless Connections
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 14Submission Harry Worstell, AT&T Labs
AnalogFront-End(Band 1)
AnalogBack-End(IF BW 2)
Digital ChannelProcessing
(Std 2)
AnalogFront-End(Band 1)
AnalogBack-End(IF BW 1)
Digital ChannelProcessing
(Std 1)
AnalogFront-End(Band 2)
AnalogBack-End(IF BW 3)
Digital ChannelProcessing
(Std 3)
General-Coverage RadioTechnology
Unique Radio Design for
Each Radio Service
Band-AgileFront-End
Single Radio
Platform Designfor Multi-Band,
Multi-Mode Use
Multi-Band, Multi-Mode Radio Equipment
Wireless “Y2K” MegatrendsNew system environments and service demands have spurredfundamental architectural and technological progress:
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 15Submission Harry Worstell, AT&T Labs
Wireless “Y2K” MegatrendsNew system environments and service demands have spurredfundamental architectural and technological progress:
Distributed-Intelligence Wireless Networks
Distributed Adaptive Wireless
Network Processing & Control
Centralized Wireless
Network Processing & Control
Wire
d N
etw
ork
MT
SO
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 16Submission Harry Worstell, AT&T Labs
New system environments and service demands have spurredfundamental architectural and technological progress:
Wireless “Y2K” Megatrends
Capacity/Quality Increases Via Adaptive Antennas
Graph 1
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Graph 1
EasyLink Enabled...
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Connected...
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Graph 1
EasyLink Enabled...
Dial> 201 555 3000
Dialing...
Connected...
login: rrm
Antenna Processor
AdaptiveArray Antennasfor MaximizedFrequencyRe-Use
Omni or SectorAntennas inCenter or Edge-Excited Cells
"Beams"Replace"Cells"
R/T R/T R/T R/T R/T
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 17Submission Harry Worstell, AT&T Labs
New system environments and service demands have spurredfundamental architectural and technological progress:
Wireless “Y2K” Megatrends
Circuit-Switching
Packet-Switching
Switched-Circuit and Packet Mode Depending on Media
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 18Submission Harry Worstell, AT&T Labs
New system environments and service demands have spurredfundamental architectural and technological progress:
Wireless “Y2K” Megatrends
Open Interfaces
SS7
Closed Proprietary
Architectures
H323
CTI
IEEE802.11
MGCP
Open Interfaces Required
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 19Submission Harry Worstell, AT&T Labs
Although easy to install, W-LANs provide spot coverage, withoutthe range, reuse, contiguous coverage, and isochronous traffic-handling benefits characteristic of cellular CAIs and networkarchitectures.
W-LAN Radio Access PointsRouter
PacketNetwork
Current Indoor Wireless LANs
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 20Submission Harry Worstell, AT&T Labs
• Peer/Peer and Client/Server• Small User Population• Isolated "Cells" and User Groups• Non-Contiguous Coverage• Indoor Operation• Limited Mobility• Mostly Asynchronous Traffic• Slower than Ethernet
A
A
A
Today’s Wireless LANs
• InterNet/IntraNet • Ethernet-Compatible Speeds• Multiple RF Bands to operate
Second-Generation Wireless LANs
A
C
BA
• Larger User Population• Full Roaming/Handoff Capability• Contiguous Coverage in Dense Areas• Wider Area Coverage for Community LANs• Mobility (Follow-Me Service)• Mix of Async and Isochronous Traffic• Higher System Utilization• Enhanced Security
IEEE 802.11Fourth-Generation ofWireless Communications
Third-Generation Wireless Communications•TDMA•EDGE•Wideband CDMA
Indoor Wireless LANs Migration
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 21Submission Harry Worstell, AT&T Labs
Enhanced IEEE 802.11 MAC
Present 802.11 MAC Enhanced 802.11 MAC
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 22Submission Harry Worstell, AT&T Labs
For the past several years, AT&T Labs has been evaluating and developinghardware and software platforms. These platforms evaluate:
•Enhanced network solutions based on extensions to the IEEE 802.11 Standard
• Mixed and simultaneous Isochronous / Asynchronous traffic management
•Full Roaming/Handoff Capability
•Contiguous Coverage in Dense Areas
•Wider Area Coverage for Community LANs
•Mobility (Follow-Me Services)
•Higher System Utilization
• Enhanced security
All while maintaining the Quality-of-Service that the AT&T brand is noted
Ongoing Labs Efforts
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 23Submission Harry Worstell, AT&T Labs
Managing Multimedia Content and Throughput
Unified Protocol/MAC
The packet communication challenge: how to provideconcentration of users with various media, preserving QOS...
FDMA, TDMA, CDMA Packet (ALOHA, PRMA, etc.)
Reservation Techniques(Circuit-Switched, Control at Base)
Contention Techniques(Packet-Switched, Control at User and Base)
Knowledge base and modeling of access methods are fundamental to engineering asystem which optimizes cost, system capacity, data latency, frequency use, etc.
Hz
1
2
3
4
1234
1 2 3 4
56
5 6
Time
1,2,3,4,5,6
Time Time
431
42 3
0 1 e e 1FB
Reserved
Contending
FB
1 423
Frame
e 1 1 e21 1
1 4
35
Frame
UserUserUserUserUserUserChannel
ChannelChannelChannelChannelChannel
Slot Slot Slot Slot
Slot SlotSlot
42
e
SlotSlot Slot Slot SlotSlot Slot SlotSlot Slot
Frame
Channel
A set of users (transmitters) wish to communicate with a radio node or coaxial head-end facility (receiver)Users must share a communication channel
Problem: How to coordinate channel usage by the users so that the channel is used efficiently?
e1
Mini-Slots Bearer-SlotsMini-Slots for Payload Management
Synchronous Media ReservationsAsynchronous Media Contention ResolutionSignaling and System Control
Bearer-Slots for Payload Communication
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 24Submission Harry Worstell, AT&T Labs
Merging of Wired & Wireless
The Future.....
Telephony, Multimedia, Paging, High Speed Internet/Intranet Services
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 25Submission Harry Worstell, AT&T Labs
Conclusion
We at AT&T Labs support the IEEE 802.11 study group in their efforts toenhance the Standard with respect to adding extensions to the MAC and movethe Standard to a 4th Generation Standard that includes a wireless networkingsolution.
We encourage the Study Group / Working Group to look at enhancements thatprovides true network based solutions that will support simultaneousMultimedia, Telephony, Streaming Video, and High Speed Internet / Intranetaccess with a cellular like CAI and enhanced security.
We are pleased to be a participant in the IEEE 802.11 committee and hope tocontinue to contribute to and support the efforts of the IEEE 802.11 StandardsCommittee and this Study Group.
AT&T LabsAT&T LabsNovember, 1999 doc.: IEEE 802.11-99/251
Slide 26Submission Harry Worstell, AT&T Labs