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Wireless ATM Development Scenario. 성 단 근 ( 成 檀根 ) 한국과학기술원 (KAIST). Contents. Wireless ATM ? Requirements Radio ATM : PHY, MAC, DLC Mobile ATM : Handoff, LM Testbed Systems (WATM Projects) Development Scenario Conclusions. Wireless ATM ?. Mobility. Wireless. Fixed / Wired.
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Wireless ATM Development Scenario 성 단 근 (成 檀根) 한국과학기술원 (KAIST) Communication Networks Research Lab.
Contents • Wireless ATM ? • Requirements • Radio ATM : PHY, MAC, DLC • Mobile ATM : Handoff, LM • Testbed Systems (WATM Projects) • Development Scenario • Conclusions Communication Networks Research Lab.
Wireless ATM ? Mobility Wireless Fixed / Wired Cellular-based Approach Cordless-based Approach PSTN First Gen. CT-1 Analog Analog Cellular Fast PSDN IMT-2000 Public CT-2 Cellular Slow Second Gen. Satellite mobile ISDN/ B-ISDN Digital cellular Wireless CT3 PCS ATM Movable or Still PCN Third Gen. Private (indoor) Cordless Telephone Wireless LAN (IEEE 802.11) Fixed B - ISDN UMTS / IMT-2000 W-ATM 1 10 0.1 100 Mbps Communication Networks Research Lab.
Wireless ATM as a General Concept Communication Networks Research Lab.
Mobile ATM B1. Handoff control B2. Location management for mobile terminals B3. Routing for mobile connections B4. Traffic/QOS control for mobile connections B5. Wireless network management Radio ATM A1. Radio physical layer A2. MAC for wireless channel (with QOS) A3. Data link control for wireless channel A4. Radio resource management Standardization (ATM Forum) • Working Group (June `96) • Recommendations (Dec. `98) User Plane Control Plane Mobility Control ATM Adaptation Layer Wireless ATM Layer Control Data Link Control Medium Access Control Radio Physical Layer Radio Access “R” Specification Mobility “M” Specification Communication Networks Research Lab.
Multimedia Service Classes and QoS • Service Classes • CBR (Constant Bit Rate) • VBR (Variable Bit Rate) : Real-time and NonReal-time • ABR (Available Bit Rate) • UBR (Unspecified Bit Rate) Communication Networks Research Lab.
Problems • Medium (Radio ATM) • ATM assumes reliable transmission media • e.g.) optical fiber => error correction • Efficient transmission of short cells • QoS guarantee over unreliable radio link • Mobility (Mobile ATM) • Signaling modifications to support mobility • Addressing (ATM, MAC, VCI/VPI) • Security Communication Networks Research Lab.
Physical Interface • Frequency Band • 2.4GHz band : 6-8 Mbps • 5 GHz band : 25Mbps (50 kcells/sec to the ATM Layer) • 17 GHz band : 155Mbps • 60 GHz band : 155Mbps or 622Mbps... • Unreliable Link (Error Source) • Multi-path fading (Dominant source) • High frequency and traveling speed => fading rate • Cell Size and Channel Utilization • Packet Size • > 1cell / PDU for effective utilization Communication Networks Research Lab.
MAC Protocols for Radio Access Interface • Integrate Services and Guarantee QoS • Distributed (WATM LAN) or Central • TDMA/Asymmetrical TDD with dynamic slot assignment (ATM Forum) Access Mode Circuit Mode Packet Mode CDMA Paradigm TDMA Paradigm FDMA TDMA CDMA • DSA/DSA++ • Dynamic TDMA • DQRUMA • Slotted CDMA • Multicode ? ? ? Communication Networks Research Lab.
Error Control (DLC) • Channel Error Recovery • Interleaving • Forward error control (FEC) • Dual - level FEC • Link Error Recovery • Auto Repeat reQuest (ARQ) retransmission • Go-back N • Selective repeat • FEC Communication Networks Research Lab.
Handoff Issues • Hard vs. Soft Handoff • Path Extension vs. Path Rerouting • Static COS vs. Dynamic COS Selection • Control Plane vs. User Plane Signaling • QoS Guarantee at Handoff • Different user load at base stations • Reserving capacity => waste of system resource Communication Networks Research Lab.
ATM Network WATM Project - Magic WAND • Private, Indoor, Business Customer Premises Network • Desktop, Nomadic User, Hand Portable Applications • ACTS Projects • 50Mbps @ 17GHz • TDMA/TDD • 50m Cell, 15 km/h • MASCARA • Wireless DLC • Intra-Switch Lossless Handover AP : Access Point Communication Networks Research Lab.
WATM Project - MEDIAN • High Speed Wireless Customer Premises LAN • Professional & Residential Multimedia Applications • ACTS Projects • 34 or 155Mbps @ 60 GHz • OFDM (512 Carriers) • TDMA/TDD Communication Networks Research Lab.
WATM Project - BAHAMA • Broadband Adaptive Homing ATMArchitecture • Ad-Hoc Wireless ATM LAN • PBS : ATM Switching Functionality + Wireless • Access Interfaces • AT&T Bell Lab. • 2Mbps @ 900MHz • 10Mbps @ ??? • TDMA • DQRUMA • Homing Algorithm • Broadcast Scheme Communication Networks Research Lab.
WATM Project - WATMnet • A Prototype Microcellular Wireless ATM Network • Mobility Enhanced ATM Signaling (Q.2931+) • NEC USA, C&C Research Lab. • 8Mbps @ 2.4 GHz • TDMA/TDD • p/4 QPSK • Dynamic TDMA • AAL 3/4 & 5 • Handover Switch Scheme Communication Networks Research Lab.
WATM Project - SWAN • Indoor Environments • AT&T Bell Lab. • 10-20m Cell • 625 kbps @ 2.4GHz • TDMA/TDD • FHSS modem • Token Passing MAC Communication Networks Research Lab.
WATM Project - MBS • Public and Private System, Indoor and Outdoor • All Multimedia Applications and B-ISDN Compatible • ACTS Projects • 34Mbps @ 60GHz • TDMA/FDMA/FDD • 4 and 16 OQAM • SR-ARQ • Network Handover with Server Communication Networks Research Lab.
WATM Project - SAMBA • Advance the MBS Evolution and Promote Its Standardization • Medical and Broadcast Applications • ACTS Projects • 34Mbps @ 40GHz Communication Networks Research Lab.
ATM-based multimedia network Media Server ATM`-SW Hand-held portable multimedia terminal Micro-cell/Pico-cell at public spaces like Hotel, Airport, Rail-station, Restaurant etc. WATM Project - AWA • Wireless ATM LAN and Public Networks • Dual Mode Access • ATM Services • NTT • 25-75Mbps@10-30GHz • TDMA/TDD • QPSK or p/4-QPSK • SR-ARQ Communication Networks Research Lab.
WATM Project - Summary Communication Networks Research Lab.
LM Frequency Bands Data Rates Environments Channel Coding Cell Size Modulation Multiple Access Technology Tree for Wirelss ATM Wireless ATM Radio ATM Mobile ATM Handoff MAC PHY DLC Hard vs. Soft Service Integration Buffering Mobile Tracking Extension vs. Rerouting QoS Guarantee Cell Integrity Mobile PNNI vs. LR Static vs. Dynamic COS Distributed vs. Central Transfer Delay Control vs. User Plane Utilization QoS Guarantee ARQ vs. FEC Forward vs. Backward Hybrid ARQ/FEC Communication Networks Research Lab.
WATM Scenario Communication Networks Research Lab.
WATM Scenario - Stage 1 • Design Objective • Wireless Channel Design • WATM Terminal + Base Station (BS) • Carrier frequency : 2.4 GHz, 5.2GHz, 17GHz, 60GHz, etc. • Radio Propagation Characteristic : Indoor, Outdoor • Multiple Access Scheme : TDMA, CDMA, etc. • Modulation : QPSK, OQAM, OFDM, etc. • Channel Coding : Interleaving, FEC • Antennas : Omnidirectional, Directional, Array • Cell Size and Link Utilization Communication Networks Research Lab.
WATM Scenario - Stage 2 • Design Objectives • Local mobility • Service Integration • WATM Terminal + BS + Switch • Dynamic Scheduling : DSA, DQRUMA, etc. • Services : CBR + VBR + ABR + UBR • Error Control : ARQ, FEC, ARQ/FEC • Hard handoff vs. Soft handoff • Forward handoff vs. Backward handoff Communication Networks Research Lab.
WATM Scenario - Stage 3 • Design Objectives • Network mobility • Interworking function • WATM Terminal + BS + Switch + ATM Networks • Handoff Signalling : Control Plane vs. User Plane • Path Routing : Path rerouting vs. Path Extension • QoS Guarantee During Handoff Procedures • Location Management • Interworking with Cellular, PCS, ATM LAN, etc. Communication Networks Research Lab.
Conclusions • Extension of ATM Services to Wireless Terminals • Technology Tree for WATM (Radio & Mobile ATM) • Various WATM Projects in Progress • Magic WAND, MEDIAN, BAHAMA, WATMnet, AWA, SWAN, MBS, SAMBA • WATM Scenario • Stage 1 : Wireless Link Design • Stage 2 : Service Integration and Local Mobility • Stage 3 : Network Mobility and Interworking Communication Networks Research Lab.