4g - Technology, Tele-trends, And Tele

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4G Wireless Networks Technology, Tele-Trends, and Tele-Prognosis WWW2004 Emerging Applications for Wireless and Mobile Access (MobEA II) R. R. Miller Communications Technology Research AT&T Labs - Shannon Laboratory Florham Park, NJ [email protected] © AT&T 2004 Mobility Evolution – 1G 4G 4G 3G 3G 2.5G 2.5G 2G 2G • • • • • Analog PHY Large Cells Incomplete Coverage Non-Uniform Quality Call Drops © AT&T 2004 Mobility Evolution – 2G 4G 4G 3G 3G 1G 1G 2.5G 2.5G • • • • • Digital PHY, Voice Mix of Large and Smaller Cells Nearly Ubiquitous Coverage Better Quality, but not Toll MOS Backward Compatible with 1G © AT&T 2004 Mobility Evolution – 2.5G 4G 4G 3G 3G 1G 1G 2G 2G • • • • • Digital PHY, Voice + Data Large, Smaller, and Microcells Ubiquitous Coverage + Capacity Slow Packet Data Backward Compatible with 1G, 2G © AT&T 2004 Mobility Evolution – 3G 4G 4G 1G 1G 2.5G 2.5G 2G 2G • • • • • Wideband Digital PHY Smaller Cells Packet + Circuit Operation Support of “Slow” Multimedia Backward Compatible to 2.5G © AT&T 2004 Life Cycle Progression of Wireless Systems Pre-Emergent Emergent 4G Market Size 3G Growth Maturity Decline 2G 1G Critical decision point for 3rd Generation Wireless standards Time Technology Anticipated & Emerging Technology “Bandwagon” Wide Usage & Low-Cost Customer Small Selective Base of Early Adopters Fragmented & Knowledgeable Sophisticated & Entrenched Demands Competition Functionality Substantial Flexibility and Convenience Shakeout in Unstructured Market More for Lower Price Survival of the Fittest © AT&T 2004 Mobility Evolution – 4G 3G 3G 1G 1G 2.5G 2.5G 2G 2G • • • • • Broadband Digital PHY Micro & Nanocellular “Viral” Coverage Model Wired-Like Multimedia Speed Computer Network Paradigm © AT&T 2004 Techno-trends: Migration Drivers Important Migration Drivers: • Higher Capacity • Better Communication Quality • More Throughput / User © AT&T 2004 Techno-trends: Info “Half-Life” & “Inconvenience Threshold” © AT&T 2004 Techno-trends: Info “Half-Life” & “Inconvenience Threshold” © AT&T 2004 Wireless System/Technology Evolution © AT&T 2004 Blending Old and New Networks Circuit/Packet Network Unification Packet Network User Voice Network Switch/Router & Transcoder Switch/Router & Transcoder Access Transport Wireless Fiber Metallic Wireless Metallic Core Circuit Network CENTRALIZED INTELLIGENCE Existing Network Future Network Existing Network Circuit/Packet Gateway Interface DISTRIBUTED INTELLIGENCE Advanced Network User Broadband Network User User Separate Voice and Packet Networks Core Broadband Packet Network (Fiber) Coax Copper Pair Wireless Transport Coax Copper Pair Wireless Access Coax Copper Pair Wireless Premises © AT&T 2004 Moving IP Convergence into the Access Domain DSL, Cable and Wireless Access frameworks will migrate to full IP compatibility Circuit-Switching PacketSwitching, QoS Controls, and Virtual Circuits © AT&T 2004 Expanding the Wireless Access “Pipe” Narrow to Broadband Access Channels Narrow Data/Voice-Rate Pipe Wide All-Purpose Pipe • • • • More Bits Wider Channel Bandwidth Service Level Agreements Remote Quality Monitoring © AT&T 2004 Preventing “Road Kill” on the Broadband Wireless Highway Wireless Connectivity Equivalent to Wired Impairments • Interference • Noise • Blocking DATA DATA DATA High-QoS Capability • Data In = Data Out • Improved Error Control • Advanced QoS Protocols © AT&T 2004 “Flattening” the Wireless Network Distributed-Intelligence Wireless Networks Circuit-based, Centralized Control Cellular Systems MSC Network Packet-based, Distributed Control 4G WLAN Systems © AT&T 2004 “Object-Oriented” Networking Access Network Transport Network Core Network “Instant Infrastructure” with Hybrid Wired-Wireless Networks Net Node Wireless at the “Last Link” Net Node Net Node Net Node Net Node Net Node Flat, Mesh-Connected Network with Arbitrary Wired/Wireless Links © AT&T 2004 Direct Delivery and Location-Dependent Services Don’t “Find-Me”, Instead “Know Where I Am” Network Info Answer? 1 Answer? 2 3 User Terminals Answer? Info Network Registration, GPS User Terminal Multiple Addresses, Multiple Terminals Multiple Terminals, Single Address © AT&T 2004 Lowering Broadband Access Modem Cost Digital Wideband Radio Modem Wireless Digital Wideband DSL Modem Digital Wideband Cable Modem Copper Coax Digital Wideband Radio Modem Digital Wideband DSL Modem Digital Wideband Cable Modem Low Cost “Universal” Moore’s Law VLSI for High Volume MultipleApplication Use Separate Processing Techniques for Various Access Media Digital Broadband Modem Digital Broadband Modem Multi-Format Broadband Modem “Engines” © AT&T 2004 Techno-trends: Broadband/Narrowband Service Fusion Separate Service Environments Voiceband Voiceband Devices Devices Voice Data Wired Wired Access Access Devices Devices Data Data Devices Devices Cellular Cellular Devices Devices Graphics E th e DSL rnet/ /Coa Data x Voice 3G Image Video less e r i W Image Voice Data Universal Universal Broadband Broadband Access Access Networks Networks Multimedia IP-Phones Global Mobility Universal Directories PDAs PalmTops Collaboration Multisession Wireless IP Phones Personal Agents Video Image Wireless Wireless Access Access Devices Devices Voice Data WLAN WLAN Devices Devices © AT&T 2004 Techno-trends: A/V, Computing, Communication Fusion 4G Broadband Service Suite 4G can deliver compelling multimedia content to users with inexpensive clients, intelligent “edge” wireless edge switches and small cells, a better value proposition for consumers Effective Bandwidth 1G, 2G, 3G Service Suite 1 4 7 2 5 8 0 Rcl Sto Clr Pwr VolEnd Slow Packet Data Paging Messaging Low-Speed Data w/ Error Control Conventional Low-Speed PSTN Toll Telephony or FAX Quality Compressed Low-Speed Telephony Voice VideoTex 8 -32 Kb/s 56 Kb/s Data 64 Kb/s Voice Digital Voice <1 Kb/s Packet © AT&T 2004 Source Coding Unification: IP Convergence “Glue” Voice Data Signaling Common Multimedia Source Coding Uniform over All Networks Multimedia Unification Video © AT&T 2004 Emergence of the “Flat” IP Packet-Based Environment Information Services Education Services Entertainment Television Information Services Software Distribution Interactive Games Electronic Shopping FFoood odM Mar artt Application Service Providers Application Platform Internet Service Providers Network Service Providers Service Platform Broadband Wireless Access Networks Transport Network Broadband Wired Access Networks 4 Information Appliances © AT&T 2004 Techno-trends: Broadband-Induced Information Exchange Growth Video/ Image Information Form Electronics Industry HQ Speech/ Audio Entertainment Industry Medical Industry 4G Wireless H/S Data Telecom Industry Computing Industry Telephone/Fax Financial/Retail/ Manufacturing Industry Generation Library/Info Service Industry Process Store Transport Information Management Sector © AT&T 2004 Background: The IEEE Standards Organization IEEE Standards Association Standards Activities Board Sponsor 802.3 CSMA/CD Ethernet 1-100 Mbps Sponsor Local and Metropolitan Area Networks (LMSC, IEEE 802) 802.5 Token Passing Ring 802.11 Wireless WLAN 802.15 Wireless Personal Area Networks Sponsor 802.16 Wireless Broadband Access 802.18 Radio Regulatory TAG 802.19 Co-existence TAG IEEE • • • 802.11: ~500 Voting Members 300+ supporting companies www.ieee802.org/11 © AT&T 2004 802.20 MBWA AT&T’s MAC Enhancement Vision Presented to 802.11 in 1999 Enhanced 802.11 MAC Present 802.11 MAC “Migrate 802.11 from an Ethernet Cord Substitute to a Common Air Interface (like Cellular)” © AT&T 2004 Background: Project 802.11 Enhanced Security Mechanisms I MAC QoS E Enhancements MAC PHY 2.4 GHz Frequency Hopped Spread Spectrum 1 Mbps 2 Mbps (optional) 5 GHz High Throughput Radio Resource Measurements Japan Extensions 5 GHz Spectrum Managed 2.4GHz High Rate >20Mbps 2.4 GHz Direct Sequence Spread Spectrum 1 Mbps 2 Mbps Published as IEEE Standard 1997 IEEE Std. 802.11-1997 Initial capabilities in White N K J H G Wireless NetworkSG Management S ESS Mesh Inter-Access Port Protocol R Fast Roaming SC Publicity Wireless Access SG Vehicular Environment F Maintenance M SC Regulatory Updates D C SG Wireless Performance Prediction A Infra-Red 1 Mbps 2 Mbps (opt) Wireless Next Generation 5 GHz 802.11a 6, 12, 24 Mbps 9-54 Mbps (opt) International Standard ISO/IEC 8802-11: 1999 Completed additions in 1999 Green B 2.4 GHz 802.11b 5.5 Mbps 11 Mbps Reaffirmed 802.11 2003 Completed work in yellow Active 2004 work in red © AT&T 2004 Device Presence: Unlocking the Value of e-Media * From Larry Brilliant’s (Vice-Chair, Cometa) Keynote at 2003 Supercomm © AT&T 2004 Techno-trends: 4G Worldwide Spectrum Alignment 2.4 GHz US/Canada (ISM*) 83.5MHz BW Usually Termed Industrial, Scientific & Medical (ISM) 3 DSSS/CCK Clear Channels Available almost worldwide; allocations being handled through World Radio Congress (WRC) 9 Most regulations support 802.11b, with some power and indoor/outdoor usage caveats 9 9 9 9 Japan Europe (all by 2004) France1 Spain Hong Kong 5 GHz 9 300 MHz BW in U.S. (3 x 100) 9 HiperLAN has harmonized with 802.11a, opening opportunity for the first “world” WLAN access standard 9 Increased band convergence anticipated at WRC-2003 9 FCC seeking alignment of 255 MHz addl. for WLAN use (5-15-03) Australia South America2, Caribbean2 China4 2400 2440 2480 2500 US/Canada (U-NII) Study U-NII Study Japan4 Study3 Europe2 South America Hong Kong Australia 5000 1 Public 5100 consultation in progress 2 Exclusions in some countries 5200 3 5300 5400 Per China MII #2001-653, #1998-178 4 National Frequency allocations are pending 5500 5600 5700 5800 5900 U-NII = Unlicensed - National Information Infrastructure (U.S. Terminology) © AT&T 2004 Techno-trends: Moving from “Micro” to “Nano” Cells Cell size reductions continue, driven by availability of inexpensive distributed computing and self-aggregating network capabilities, resulting in full broadband service with battery economy. Maritime Mobile HF Radio Service (~300 mi) 1,000,000 100 Watts Advanced Mobile Phone Service (AMPS) (~8 mi) 100,000 Cell 10,000 Radius (Feet) MJ-MK Mobile Telephone (~60 mi) 10 Watts Cellular Expanded Service (~4 mi) Metroliner Train Telephone (~15 mi) The 3G “Sweet Spot” Cellular MicroCells (~2 mi) 1,000 100 mW .01 mi2 PCS Microcells (~0.5 mi) 100 1950 1960 1970 1980 1 Watt Mobile/ Portable Maximum Power Output 1990 30 mW WLAN Nanocells (~.06 mi) 2000 The 4G “Sweet Spot” 2010 Year © AT&T 2004 A View of Small Cell/Large Cell Illumination Two-slope model, with steeper slope as propagation falls deeper into multipath environment 40 Slope transition breakpoint moves in as base height is reduced. (~500’ for 5m pole, 3200’ for 80’ tower) 60 Path Loss, dB 80 Operation beyond transition point requires disproportionately higher power to overcome loss and to sustain sufficient fade margin (QoS) 100 120 140 160 180 0.01 Typical Suburban Environment 0.1 1 Distance from Base, Km 10 hb = 5m Base Height hb = 25m Base Height Median path loss, 5m Median path loss, 25m Client Antenna Height: 1.8m Low base height mandated by aesthetic and siting concerns makes 1000’ cells a “sweet spot” for coverage, transmit power, and link predictability/availability. © AT&T 2004 Techno-trends: Capitalizing on Small-Cell Predictability 40 60 Path Loss, dB 80 Data set representing measurements taken in particular neighborhood shown in overlay 100 120 140 hb = 5m Base Height hb = 25m Base Height Median path loss, 5m Median path loss, 25m Client Antenna Height: 1.8m 160 180 0.01 0.1 1 Distance from Base, Km 10 Takeaway: Small cells can be modeled with better accuracy © AT&T 2004 A Perspective on 3G “Reach” vs. “Rate” All things being equal, power will scale with channel bandwidth PT = L90 - Gm - Gb - Isd + SNR0 + [ -174 dBm/Hz + NF + 10 log B ] For a given distance, frequency and environment PT L90 Gm Gb Isd SNR0 -174 dBm/Hz NF 10 log B - transmit power maximum loss to achieve a given SNR0 mobile terminal antenna gain base antenna gain space diversity improvement required signal to noise ratio thermal noise noise figure 10 x log of channel bandwidth (in Hz) © AT&T 2004 Smaller Cells, Smaller Batteries For multi-megabit rates, small cell systems will remain a more practical solution for long battery life in portable devices. 100 W Impact of Current Rechargeable Battery Capacity on Continuous Transmission at Multimedia Rates Rechargeable Battery Capacity Trends Moore's Law Device Transmit Power 30 Sec 10 W 144 kbps 1.5 Mbps 6 Min 8-13 kbps 1W 0.1 W 144 kbps 8-13 kbps 11 Mbps 1.5 Mbps 144 8-13 kbps kbps Macrocellular Microcellular Nanocellular Systems Systems WLAN Systems (~8 mi. cells) (~1/2 mi. cells) (300+ ft. cells) © AT&T 2004 1 Hr 10 Hr Techno-trends: Centralized vs. Distributed Intelligence Cellular The availability of inexpensive computing platforms has allowed intelligence to be pushed further toward the network edge... 802.11 …Resulting in networks with greater resiliency, faster deployment and decreased labor to set up and maintain © AT&T 2004 Techno-trends: “Coverage-First” Transitions to “Viral Growth” 2G/3G Wide-Area Macrocells Microcells Picocells 4G Self-Aggregating Local Nanocellular Networks © AT&T 2004 Techno-trends: User Device/Service Expectations • Wireless = Central Theme • Telephone Handset + Radio • Wireless = Part of Service “Bundle” • Handset + 2-Way Pager + Internet Browser + Data Bank + Media Player + Remote Control + Geographic Locator + Radio 2G-2.5G 2.5G-3G 3G-4G • Voice = Part of the Service “Bundle”: VoIP Built-In • Full Multimedia Support and Expanded User Interface • The “Anywhere, Anytime Appliance” • Wireless Capability is a “Given” © AT&T 2004 Techno-trends: Traffic Management Evolution 4G Wireless Public WLAN ISDN © AT&T 2004 Techno-trends: Service/Transmission System Maturation Wireless “Generation” 1G 2G 2.5G 3G 4G UWB? © AT&T 2004 Techno-trends: Deployment and Service Needs First-Generation Wireless LANs F1 F1 F1 • • • • • • • • 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 IEEE 802.11 Fourth-Generation Wireless Communications F1 F1 F1 F2 Second-Generation Wireless LANs • Data-Centric Internet/Intranet • 10BT Ethernet-Compatible Speeds • Multiple RF Band Interference Control • • • • • • • • • • Larger User Population 100BT Ethernet Speeds Full Roaming/Handoff Capability Contiguous Coverage in Dense Areas Wider Area Coverage Mobility (Follow-Me Service) Data, Voice, Multimedia Higher System Utilization/Reuse Enhanced Security Automatic Radio Resource Management F1 F2 F3 F1 Third-Generation Cellular • • • • Voice-Centric 1BT Equivalent Ubiquitous Coverage Sophisticated Resource Reuse © AT&T 2004 3 3 Spatial Frequency / Time Reuse 2 1 3 1 3 3 1 1 3 3 2 1 3 3 2 2 1 1 1 = Freq 1 2 = Freq 2 3 = Freq 3 3 3 2 2 3 1 3 1 2 2 2 1 2 2 Time Domain QOS-Based Protocol 3 1 3 3 1 2 2 1 2 1 1 2 2 2 Qo S 1 Qo S 2 Qo S 3 Ac ces s Le ga cy Techno-trends: Increasing Reuse Dimensions 2 2 1 AP Time Interval 1 AP Time Interval 2 AP Time Interval 3 © AT&T 2004 Cognitive Radio and Automatic Resource Management Benefits: Graph-Coloring Algorithm -6 -5 -6 • Reduced Installation Planning • Improved Coverage • Modular Capacity Additions • Self-Healing Capability Automatic Reciprocity Measurements F2 G F3 C A F Channel/Time Assignment Optimized for Minimum Co-Channel Interference D E F4 F1 B F6 F5 F2 F1 H © AT&T 2004 Techno-trends: “Smarter” Radios Multi-Standard Access and Digital Radio Processing Technology Front-End 1st IF 2nd IF Demodulator Frequency Synthesizer Power Amp Buffer Amp Front-End 1st IF Power Amp Buffer Amp Front-End 1st IF Demodulator Frequency Synthesizer 1 1 4 2 5 3 6 8 0 # 4 2 5 3 7 * 8 0 9 7 # * 6 Rc l Sto Clr Pwr Vo l E nd 9 Rc l Sto Clr Pwr Vo l E nd 1 4 2 5 3 6 7 * 8 0 # uC Voice Processing 2G Radio Channel Processor uC Voice Processing 3G Radio Channel Processor uC Voice Processing 4G Radio Modulator 2nd IF The Problem: Channel Processor Modulator Multiple Standards Threaten to Complicate Spectrum Use and Reinforce User "Utility Belt" Device Mentality 9 Rc l Sto Clr Pwr Vo l E nd 2nd IF Demodulator Frequency Synthesizer Power Amp Buffer Amp Modulator The Solution: Create Platforms for Multi-Band, Multi-Mode Devices and Radio Ports by Utilizing High-Performance DSP Technology to Realize "Software Radio" BB Front-End WB 1st IF A/D Digital IF Engine D/A Digital IF Engine BB F requency Synthesizer 1 2 3 4 5 6 BB Power Amp WB Buffer Amp Channel Proces sor DSP Multimedia Source Coder DRP Radio (e.g.TDMA, WCDMA, WiFi) 8 9 7 0 # * Rc l Sto Clr Pwr Vo l En d RF Band of Interest Digital EQ, RAKE Engine Broa dban d An alog "Front-End" Frf I I Q Q Baseband Information LO Analog translation to low I F Fif Digitizat io n at lower IF Frequency selection via digital filterin g DSP-base d extraction of comp le x envelop e components © AT&T 2004 “Computing a Radio” with Precision RF Selectivity © AT&T 2004 Techno-trends: A DRP “Motherboard” Example An AT&T Labs 3-Carrier DRP Cellular Base Station 16” © AT&T 2004 Techno-trends: Smarter Antennas and “MIMO” Utilize independent information from multiple antenna elements to extract spatial information. Track desired signal "signature" allowing independent antenna arrivals to be correlated while interferers remain uncorrelated. Can optimize signal-to-noise ratio for a specific signal spatially-separated from interferers Digital Radio Processing to simplify extraction of multiple antenna images Multiple-Input, Multiple-Output (MIMO) Adaptive Array Antennas: “Beams” Replace “Cells” EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Graph 1 EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Graph 1 Microcell Systems (In-Building / Campus) EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Graph 1 Adaptive Null Steering/ Interference Cancellation Macrocell Systems Graph 1 EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Graph 1 Omni or Sector Antennas in Large Cells or In-Building Distributed Antennas Switched MultiSector Antenna Processor EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Graph 1 Graph 1 EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Graph 1 EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Rcvr Full Adaptive Array with Per-User Optimized Beams EasyLink Enabled... Dial> 201 555 3000 Dialing... Connected... login: rrm Benefits: Capacity enhancement More effective than diversity Can be used to combat fading, interference Particularly attractive for fixed/nomadic wireless application Dynamically-switched packets © AT&T 2004 Techno-trends: Improved Error Correction Coding Simplified Space-Time (S-T) Coding Concept Input Stream Standard Coding Standard Coding Copy A Copy B Fading, Interference Space-Time Decoding Space-Time Coding Input Stream Coded Stream A Coded Stream B Space-Time Coding Recovered Stream Recovered Stream Fading, Interference Space-Time Decoding Benefits: • Inherent Transmit and Receive Diversity • Coding Gains over Conventional Diversity Systems • Can be extended to Frequency Diversity Applications © AT&T 2004 Techno-trends: Media Access Control © AT&T 2004 A Broadband QOS Protocol Example An AT&T Labs Research-Developed QOS “Toolbox” for Premises and Local Access Systems Benefits: Multimedia Service Support (Time-Bound, Streaming, Data, etc. with Dynamic Sharing) Multi-Transport PHY Support (Simplex/Duplex and/or Long Propagation Delay PHYs) Statistical Multiplexing Support (Priority Grant, Flow Control, Traffic Adaptation) Characteristics: Unblocked Reservation/Transmission for Real-Time Traffic (No Dropped/Delayed Packets) Scheduling Algorithm for Reservation and Servicing (BW Efficiency and QOS Guarantees) Combined Unblocked and Contention Reservation for Streaming/Bursty Traffic Application to 802.11 Wireless LAN QOS Management Uses Current 802.11 Distributed Coordination Function and Control Set Establishes New Point Coordination Features (Resource Mgmt/Disciplined Superframes) Supports Current PCF Operation, Adds Contention-Free and Managed Contention Modes Responds to Performance-Based and Media-Oriented QOS Declarations Compatible with Emerging AT&T Packet Network QOS Signaling Formats © AT&T 2004 Superframe B D1 + Poll Ack + Poll MultiPoll U1 + Ack VS13 VS31 DlyAck VS28 CC S4 (NoAck) Traffic Interval CC + Ack D1 Unused Access Slot Upstream (to AP/Base) Downstream (to STA/Client) MediaPlex in Action - Reservation, Scheduling, and Polling RR RR RR Access Interval U2 Traffic Interval CFEnd RR B RR Supplementary Access Interval PCF Managed Contention Period • Disciplined Timing • Separation of Access and Bearer (and Legacy) • Controlled Contention Slotted Access • TSPECs • Polling/Reservations • Time Interval Protection © AT&T 2004 (E]DCF CSMA Period Controlling Time Resource and QoS via HCF (polling example) Applications VoIP Data Provides ProvidesTraffic TrafficSpecification Specification(TSPEC) (TSPEC) Response and Response andManagement Management: : • • QoS QoSbased basedQueuing Queuing • • TXOP TXOPbound bound • • Throughput Throughputallocation allocation • • Rate fallback Rate fallbackalgorithm algorithm • • Stream StreamSession Sessionmanagement management • • CC/RR CC/RRprocess process • • Radio RadioResource ResourceManagement Management Video TSPEC Data IEEE 802.11 MediaPlex MAC Scheduler Data TSPEC TSPECdefines definesthe the characteristics and QoS characteristics and QoS expectations expectationsofofaauniunidirectional traffic stream. directional traffic stream. Data Video VoIP Individual Streams/TSPEC Limited by: • total number of packets limits <= n or • total throughput limits <= T or • total TXOP limits <= txop Superframe Queuing Where: Number of packets (n) = Throughput (T) / norminalMSDUsize Throughput (T) = TSPEC_meanDataRate x SuperframeInterval Transmit opportunity (txop) = norminalMSDUsize x n / transmitRate Superframe Superframe Time allocated to AP#2 © AT&T 2004 Beacon AP#1 Data AP#2 Data AP#2 Data AP#2 Data AP#2 Video AP#2 CC AP#2 Beacon AP#2 Time allocated to AP#1 Data #2 Data #2 Data #1 Data #1 Data #1 RR RR CC VIDEO VIDEO VoIP #1 Time allocated to AP#2 Beacon AP#1 Data AP#2 Data AP#2 Data AP#2 Data AP#2 Video AP#2 CC AP#2 Beacon AP#2 Data #2 Data #2 Data #1 Data #1 Data #1 RR RR CC RR VIDEO VIDEO VoIP #1 Beacon AP#1 Time allocated to AP#1 MediaPlex Delivers - Actual System Measurements FTP Tests Throughput (MBps) 5.703 4.860 6 5 TCP Tests 6 4.352 4.730 4.456 4 5.431 4.743 5 4.841 4 Throughput 3 (Mbps) 2 3 2 1 1 PUT 0 GET mediaplex ad-hoc FROM STA TO AP 0 operation Data Direction FROM AP TO STA mediaplex ad-hoc mediaplex ad-hoc ad-hoc mediaplex ad-hoc vs. mediaplex UDP Tests When compared to current DCF (ad-hoc) operation, MediaPlex 6.000 5.000 provides QoS with high system Throughput 4.000 3.000 (Mbps 2.000 throughputs---even under 1.000 0.000 overload conditions---and does so with low protocol overhead. ) up - ad -h oc d own - ad -h oc m ed i a m ed i a p l ex p l ex uplink 64 1472 1024 512 256 128 Packet size dow nlink MediaPlex Ad-hoc © AT&T 2004 Comparing MAC QoS Protocol Approaches DCF (Current) Active QoS Streams H M L EDCF/EDCA (TGe) H M L HCF/HCCA (TGe) MediaPlex H M L H M L Superframe Entering Packet & Client Access Queues QoS No QoS Prioritized QoS (Mandatory) Parameterized QoS (Mandatory) Parameterized QoS HCCA + Optional Features Coordination Distributed Distributed Distributed + Point Point Legacy Support N/A Yes Yes In DCF/EDCF Interval Channel Access CSMA CSMA CSMA + Polled Access Polling & Controlled Contention Admission Control None TSPEC Acceptance/Denial TSPEC w / Admission Control TSPEC w / Point Admission Control as QoS Class SLA Mgmt. No SLA Mgmt. No SLA Management Possible SLA Mgmt SLA Management Resource Reuse CSMA CSMA Possible Resource Reuse in CC interval Synchronized Reuse Intervals © AT&T 2004 TGk: The First Step in Managing the Radio Resource Migrating Current MIBs… 802.11 NETWORK 802.1x LINK/MAC – Configuration for STA and very limited proprietary RF measurements – Widely implemented in APs, but not standardized – Very simple monitoring of global AP statistics (proprietary implementations only) – Detailed auth state for individual 1x ports – Also some per port statistics – Not widely implemented in access points today PHY Bridge MIB – Possible to get some info on which STAs are associated with an AP – Implemented in some APs – Not 802.11 specific, little MAC, and no PHY statistics To… Standardized RF Measurements and Methods • Basic measurements available to upper layers from AP and Client - Neighbor lists for AP’s Client association to AP lists Noise histograms Accurate power level measurements in dBm referenced at the antenna • Better diagnostics - Obtaining information in a standard form from all equipment • Enable better frequency planning and network optimization and performance - Automated signal/interference surveys • Enable new services - Location awareness capabilities for AP’s and Clients Radio Resource Management Study Group begun by AT&T in 2003 © AT&T 2004 Porting CelluLAN Fundamentals to 802.11 WNM Task Group Migrating Present Mechanisms… • Radio Resource Management via CSMA and backoff • Disorganized Reuse • No Coordination (except proprietary methods) • Interference growing • Channels likely to be too noisy for QoS NETWORK LINK/MAC PHY To… Disciplined DisciplinedRadio RadioResource ResourceManagement Management •• Reuse Reusevia viaspace, space,time, time,frequency frequency •• AP’s syncronized from common AP’s syncronized from commonbackbone backbone •• AP’s/Clients AP’s/Clientscommunicate communicateacross acrossRF RFchannel channel •• Discovery Discoveryprocess, process,followed followedby byself-organizing self-organizing •• Enable Auto-configuration Processes Enable Auto-configuration Processes •• Enable EnableCognitive CognitiveRadio Radiointerference interferenceavoidance avoidance Radio RadioResource ResourceManagement ManagementStudy StudyGroup Groupbegun begunby byAT&T, AT&T,final final approval approvalin inMarch, March,2004 2004(Task (TaskGroup GroupAnticipated Anticipatedin inMay, May,2004) 2004) © AT&T 2004 A Generalized Multimedia WLAN Enterprise Architecture SYSTEM SERVER Network Administration Radio Port Interport Networking 100 BaseT TCP/ IP Mobility Management Operations & Record-Keeping 100BaseT Radio Port LOCAL ETHERNET NETWORK Data Client 100 BaseT Radio Port T1, FR, ATM, OC-3, etc. 100 BaseT Telephony Client Authentication & Security NATIONAL PACKET NETWORK (FR, ATM, SONET) Radio Port Video Client © AT&T 2004 Next-Generation Services and Human Interfaces Defining the “Multimedia Modal Distance” 1960-80 1920-30 Individual Mouth/Ear Interfaces Separated from Terminal 1990-99 PCS/Videophone Era -Yesterday revisited... Flip-Phone Only Approximates Modal Operation using Miniaturized Handset Video with No Modal Distance Conventions Trimline Era -Dial/Audio Interfaces Combined 1 2 4 5 7 * 1900-1920 No Controlled Audio Interface Short-Range User/Terminal Separation 1930-60 300/500/2500-Set Era -Handset Establishes Modal Distance Dialing Interface at Terminal Cordless Era -Entire Human Interface Untethered via Radio 1980-90 3 6 8 9 0 # Rcl Sto Clr Pwr Vol End 21 st Century Communicators Multimedia Modal Distance Audio/Video Info Content Anthropomorphic Interfaces Fusion of Communication and Information Management The Challenge for Personal Wireless IP Terminals: Create a user environment as intuitive, comfortable and easy to use as today’s voice telephony model © AT&T 2004 Wireless IP Device Service Enablers Candidate Features for Next Generation Wireless IP Terminals © AT&T 2004 An Example “Combination” Device in Desktop Use An Experimental Multimedia Terminal: Desktop Mode © AT&T 2004 Using the “Combination” Device as a Portable Handset An Experimental Multimedia Wireless Terminal: Handheld Mode © AT&T 2004 WVoIP – The “New” Telephony Multimedia Infopads Transportable Nomadic Handhelds and Dual-Mode Cellular/WiFi (1Q04) Wearables Pocketables WiFi phones are becoming available now • • • • “Cellular” and “cordless” form factors Dual-mode cellular/WiFi phones announced (Motorola, Nokia..) Applications becoming available for PDAs Talk/listen time comparable to existing handsets • • • • Carrier-Grade QoS Better Radio Channel Processing – New VLSI SIP VoIP protocol additions New services Improvements Underway at AT&T Labs - Research Takeaway: WVoIP is being fueled currently by businesses converting to broadband multimedia networks © AT&T 2004 WiFi (In) Security Who thinks it’s important now: Enterprise premises WLANs Businesses using teleworking/telecommuting, ROBOs and SOHOs Government markets Why it will become more important: Increasing use of networked WiFi service will breed more hacking Introduction of telephony, image and video content will increase public sensitivity Increasing use of “hot spots” by corporate employees Digital rights management and identity/location/data security Three security schemes are available: 802.11 Wired Equivalent Privacy (usually paired with MAC address authentication) Intended for privacy, not security Part of original 802.11, based on RC4 encryption algorithm (used in packet cable) Encrypts airlink to AP only Protects user packets, not complete airlink Requires user to know WEP key to associate (usually same key used for all network APs) Already compromised – weak key management, but encryption algorithm still effective 802.11 TGi Security MAC Task Group Interlocks with WiFi Protected Access (next page) WEP RC4 with improved key administration and path to stronger encryption Sets up airlink security to each AP, not whole network Still no encryption of control frames (possible system vulnerability) Complicates handoffs, since new link cannot use same key (transfer delay) IPSEC Encrypts user session over entire network end-to-end Handles multiple tunnels simultaneously (needed for telephony control/speech) Encapsulation allows handoffs without renegotiation Allows “open” radio access network (don’t need keys to associate) Requires device software “shim” or hardware in clients © AT&T 2004 A Security Migration Plan 802.11 TGi Other Features BSS Wi-Fi Alliance WPA IBSS Pre-authentication (Wi-Fi Protected Access) Key hierarchy • Implement what is stable and bring it to market • Continue to upgrade to 802.11i Key management Cipher & Authentication Negotiation Data Privacy Protocols TKIP* CCMP+ * Temporal Key Integrity Protocol (TKIP) provides minimal level of data privacy for pre-RSN hardware conforming to the 1999 issue of 802.11 + Counter with Cipher Block Chaining Message Authentication Code Protocol (CCMP), an AES-based protocol, provides robust data privacy. Any implementation claiming to provide security shall implement CCMP © AT&T 2004 Full 802.11i Standard Adherence 802.1x Secure WiFi Roaming – What’s the Problem? • Fundamental difficulty: WiFi is a Local Area Network – Compare with GSM cellphone (a single, precisely defined Common Air Interface standard), where secure roaming was built into original design. – WiFi is not a CAI, only a substitute for Ethernet cord – WiFi service solutions evolving as wide-area applications are recognized • Heterogeneous environment – Employee’s premises vs. residential vs. other business vs. public – Overlapping service providers – Free vs. for-pay • Complex configuration profiles – – – – Network configuration: Fixed/DHCP Access authentication: 802.1x vs. Web vs. open Security settings: WEP on/off Multiple authentication steps • Handoff between dissimilar systems; re-configuration © AT&T 2004 Techno-trends: Security Moves Up the “Stack” Security Gate Example Hacker PGP Info Thieves Secure Shell Web Browser Virus Breeders IPSEC Encryption Specialists IP Authentication Identity Spoofers WEP Privacy Busters Data Link MAC Address Verification Access Crackers Physical Hop, Chip, and Jump (Frequency, Modulation, Small Cells) Sophisticated Hardware Hackers Application Presentation Session Transport Network © AT&T 2004 “Hot Spots” and VPNs as a Wide-Area Roaming Substitute Enterprise 802.11 √ Ethernet? Cellular? Semi-Public 802.11 √ Cellular? Payphone? Public 802.11 √ Cellular? Payphone? BB Kiosk? VPN VPN VPN Home 802.11 √ Bluetooth? Powerline? HPNA? Ethernet? VPN VPN © AT&T 2004 802.11 Reaches for Space Command and Control of Space Assets Through Internet-Based Technologies Demonstrated The NASA Glenn Research Center successfully demonstrated a transmission-control-protocol/ Internet-protocol- (TCP/IP) based approach to the command and control of on-orbit assets over a secure network. This is a significant accomplishment because future NASA missions will benefit by using Internet-standards-based protocols. Benefits of this Internet-based space command and control system architecture include reduced mission costs and increased mission efficiency. The demonstration proved that this communications architecture is viable for future NASA missions. This demonstration was a significant feat involving multiple NASA organizations and industry. Phillip Paulsen, from Glenn's Project Development and Integration Office, served as the overall project lead, and David Foltz, from Glenn's Satellite Networks and Architectures Branch, provided the hybrid networking support for the required Internet connections. The goal was to build a network that would emulate a connection between a space experiment on the International Space Station and a researcher accessing the experiment from anywhere on the Internet, as shown in the figure. The experiment was interfaced to a wireless 802.11 network inside the demonstration area. The wireless link provided connectivity to the Tracking and Data Relay Satellite System (TDRSS) Internet Link Terminal (TILT) satellite uplink terminal located 300 ft away in a parking lot on top of a panel van. TILT provided a crucial link in this demonstration. Leslie Ambrose, NASA Goddard Space Flight Center, provided the TILT/TDRSS support. The TILT unit transmitted the signal to TDRS 6 and was received at the White Sands Second TDRSS Ground Station. This station provided the gateway to the Internet. Coordination also took place at the White Sands station to install a Veridian Firewall and automated security incident measurement (ASIM) system to the Second TDRSS Ground Station Internet gateway. The firewall provides a trusted network for the simulated space experiment. © AT&T 2004 AV Net PC Net -----------CABLES------------- -----------CABLES------------- Narrowband MODEM Broadband MODEM The Current Fragmented Home Termination Model Phone Net Home Control Net TV VCR Audio System STB Camcorder... PC Printer Scanner... Phone Fax... Environmental Security Medical Domestic app… © AT&T 2004 The Networked Home: The Premises Premises • Broadband communication services are made more valuable if users can easily access them • People who want broadband connectivity want the service, but not disruption of their homes to get it • Installation of home networks can be a labor-intensive and costly endeavor for service providers and homeowners alike © AT&T 2004 Home Gateway Termination Model 2005+ Vision Wireless Narrowband GATEWAY Broadband IP Home QoS Networks Wireless Legacy Eqpt. Entertainment Productivity Utility Wireless Audio Video Telematics Vehicle Monitoring Etc… TV VCR Audio System Remote Control Camcorder... PC Printer Scanner... Phone Fax Environmental Security Medical Domestic apps… © AT&T 2004 Bringing Broadband Home: The Wireless IP Network Delivery Trial Cable Network Cable Modem Voice Client 802.11 Data Client 802.11 Video Client 802.11 Access Port Cable Head End Block Converter CMTS 802.11 Call Agent Layer 2 Switch MediaPlex QoS Voice Trunk Gateway Services Platform Router Customer Premises Internet House 1 Houses 2-25 PSTN FP Network Lab AT&T Firewall Server/ Database AT&T Intranet Router © AT&T 2004 Broadband 4G for The Campus and “The Burbs”: A Vision Broadband Backhaul © AT&T 2004 Field of Use for Next-Generation Systems Peak Data Rate “The Right Tool for the Right Job” Higher Rate, Less Mobility 100 4G H/S Wireless LAN Megabits per Second 5 GHz Unlicensed 10 4G Wireless LAN 2.4 GHz Unlicensed 1 3G Fixed or Pedestrian Bluetooth 3G/802.16 Wireless Various Bands Zigbee .1 PANs Wider Area, More Mobility 3G Mobile 2.4GHz 2.5G Mobile/Pedestrian Zigbee (US) Zigbee (Europe) 2G Wireless 800 MHz, 2 GHz Range 10 feet 100 feet 1 mile 10 miles © AT&T 2004 A New Concept: Multi-Tier Diffuse-Field Wireless Networks Core Fiber Backbone MAN Metro Fiber (DS3) Backbone 802.16 PTMP WMANs `` H/S Metallic (VDSL,PON) 802.11 PTMP `` Local L/S Metallic (DSL,100BT) WLANs 802.11 WLAN `` Metallic (T/R, 10BT) Prem 802.15/Zigbee WPANs `` Cord (RS-232) RFID Wireless Now Supports Multi-Tier Architectures Like Wired Networks – – – – – More Throughput, Higher Quality, Lower Cost, Edge Intelligence, QoS Each Layer Demultiplexes Throughput from Layer Above “Network of Networks” Approach, Like Internet “Mix and Match” Architectural Elements TCP/IP “Glue” Protocol Convergence Layer, Software Defined Interfaces © AT&T 2004 Wrap Up…And Thanks!