Contents Ⅰ Overview of WiBro Service Ⅱ WiBro Standardization Ⅲ WiBro Technology IV WiBro Business Plan in KT

I. Overview of WiBro Service (1/8) Definition “WiBro service means high speed wireless internet service which is available anytime, anywhere using portable terminal in stationary or even in mobile environment.”  WiBro: Wireless Broadband “Stationary or Mobile Environment” “Any time, Any where” “High Data Rate” “Low Tariff” ■ Seamless Service even in outdoor such as street, park and etc. ■ +1 Mbps User Data Rate (Day 1) ■ Higher Data Rate (Future) ■ Nomadic ■ Vehicular Mobility ■ Low CAPEX ■ Roaming with WLAN and CDMA Handset terminal for Notebook PCMCIA card for Notebook and PDA Handset PDA Handheld PC Notebook PC

♪ I. Overview of WiBro Service (2/8) Seamless, Ubiquitous Experience Service Concept Mobile Automobile Service Office SD MMC SIM SD MMC Seamless, Ubiquitous Experience Infra Info IC Card Personal Info Home Shop Ｅ-Tower ♪ Game DVC STB TV Map Info PC Digital Contents SD MMC Audio DVD Telephone Outdoor F - 7

High speed DSL(ADSL,VDSL ..) I. Overview of WiBro Service (3/8) Service Positioning Mobility Tariff Competitiveness Service beyond the bounds of WLAN, CDMA 1x(EV-DO), IMT2000 High 3G (IMT-2000) Data Rate Mobility 2G (IS-95, Cellular) WiBro Nomadic Portability Cordless WiBro Cordless phone WLAN DATA Rate IMT-2000 Fixed Wired Phone High speed DSL(ADSL,VDSL ..) Service Comparison Item WiBro High Speed DSL WLAN Mobile Com. Service Area Outdoor/Indoor Indoor Indoor(Hotspot) Data Rate High speed Ultra high speed Very high speed Med/Low speed Mobility High No Low Very high Contents Wired/Wireless Contents Wired Contents Wireless Contents Tariff Relatively Low Terminal Smart phone, PDA, Notebook etc. Desktop, Notebook PDA, Notebook Cellular phone, PDA

Requirement of WiBro Service I. Overview of WiBro Service (4/8) Service Class ■ Interactive Service: Best-efforts Web Browsing, Interactive Game, etc. ■ Streaming service (rtPS: Real Time Poling Service) VoD, MPEG, etc. ■ Back Ground service (nrtPS: Non Real Time Poling Service) FTP, E-MAIL, SMS, multicast/broadcast, MMS, Push etc. ■ Real Time Service (UGS: Unsolicited Grant Service) VoIP Requirement of WiBro Service ■ Provide the way to use high speed internet service not only in home but also in outdoor → Equivalent data rate to xDSL per user ■ Maximize the usage over the allocated spectrum ■ Maximize the spectral efficiency ■ Extend the service coverage ■ Reduce the cost per bit ■ Low power consumption at AT ■ Faster handoff

I. Overview of WiBro Service (5/8) Customer Needs ■ In Korea wireless internet service is mainly used for entertainment (58%), communication (email/café 17.6%) and business (9.3%). ■ CDMA 1X(EV-DO) shows poor service quality, insufficient contents despite high tariff system and WLAN has several shortcomings such as service coverage and QoS problems in spite of high speed data rate and low tariff system. ■ Customer needs of WiBro service is high speed data rate and low tariff system, which are the accelerating factor for widespread use of wireless internet. Terminal  PDA, Notebook Service  email > game … Service area  including mobile status PDA Notebook Handheld PC Smart phone Handset 42.1% School/office 59.5% 56.7% 36.3% 50.6% Bus/Subway 30.2% 28.6% Street 9.3% 8.7% Indoor Web Browsing 3.5% email Game Messenger MMS Business trip 7

Seamless, Ubiquitous Experience I. Overview of WiBro Service (6/8) Total Access (Sprint/Nextel) Work Domain Home Seamless, Ubiquitous Experience Elsewhere Portable Remote Access Services Field Service Apps Campus W- PBX Services Portable Services in Public Hot-Spots Mobile B-to-C M-Commerce Services Mobile Office (Voice and Data Apps) High BW Connectivity Video Streaming - Conferencing Apps Portable Office F - 7

Technical Consideration (Sprint/Nextel) I. Overview of WiBro Service (7/8) Technical Consideration (Sprint/Nextel) True Broadband Speeds 1 Mbps/user NLOS Operation up to 10 us delay spread High Link Budget > 160 dB High # of Simultaneous Sessions > 100 per carrier High Spectral Efficiency > 2 bps/Hz/sector Large Channel Bandwidths > 5 MHz Low Latency < 50msecs Deep Indoor Penetration 90th percentile inside IP QoS class, service, protocol, application based differentiation, VoIP Portability seamless IP session handover Mobility (Optional Parameters) inter-cell handover up to 120 km/hr IETF based L3+ standard IP based protocol support Low Power Integrated CPE/PCMCIA consumer device form factors

I. Overview of WiBro Service (8/8) Operators Vision ■ End-to-End Wireless IP Data Services Design ■ Better than 1+ Mbps Performance User Experience ■ Mobility for Data with IP QoS support Day 1 - Non real time Future - Real time ■ Integrated wireless backhaul capability ■ True International Standard and Devices Requires flexibility for bandwidth and band plans Need to support both TDD and FDD based on spectrum allocations ■ Devices examples: Desktop modem, PCMCIA card, Handset, Compact Flash Embedded into all broadband capable consumer devices ■ 10x+ competitive advantage to current 3G systems

Technical Committees (TC) Common Infrastructure II. WiBro Standardization in (1/8) TTA organization Technical Assembly (TA) Coordination Committee (CC) Strategic Planning Committee (SPC) Technical Committees (TC) Project Groups (PG) Common Infrastructure (TC1) Information Security, Internet Security, Biometrics, Welfare Communication, IC Card, SoC, Disaster Recovery, Embedded S/W Transmission (TC2) Optical Transmission, Optical Internet, Signaling, Routing Protocol, Quality of Service, VoIP, ENUM, NGN, Active Internet, Charging & Interconnection, Network Management, IPv6, LAN, DSL, Digital Home Radio Communication (TC3) Digital TV, DMB, Digital Cable, WPAN, Wireless LAN, Propagation Measurement, NGMC, LBS, Telematics, Portable Internet (WiBro) IT Application (TC4) WEB, Multimedia Application, Workflow, E-commerce, Public information, MetaData, S/W process, S/W Components. NGIS, ITS, Grid

WiBro standardization status II. WiBro Standardization (2/8) WiBro standardization status TTA has begun WiBro Standardization since June 2003. Establishment of 2 Working Groups and 2 Ad Hoc WiBro Standardization Activities & Timeline is as follows. Phase I Standardization for WiBro was finished. 3Q 2003 Definition of Service/System Requirements 4Q 2003 Preparation of the Draft Standard Definition of major system parameters Definition of items/criteria/conditions for Evaluation Collection and Evaluation of Baseline Proposals Selection of Baseline Proposal(s) 1Q 2004 Completion of Draft Standard 2Q 2004 Approval and Notification of Standard Phase II Standardization for advanced WiBro is in progress. 3Q 2004 ~2Q 2005 Harmonization with IEEE 802.16e Approval and Notification of New Standard including performance enhanced technologies such as MIMO, smart antenna etc.

Frequency Reuse Factor [bps/Hz/cell(sector)] II. WiBro Standardization (3/8) Major Decision TTA approved the Major System Parameters & Radio Access Requirements. (Jan. 31. 2004) Major System Parameters Radio Access Requirement TDD Frequency Reuse Factor Duplexing 1 OFDMA Multiple Access 10 [MHz] Channel BW Mobility ≤ 60 [Km/h] Service Coverage ≤ 1 [Km] Spectral Efficiency [bps/Hz/cell(sector)] Max. DL / UL = 6 / 2 Aver. DL / UL = 2 / 1 Handoff ≤ 150 [ms] Throughput (per user) Max. DL / UL = 3 / 1 [Mbps] Min. DL / UL = 512 / 128 [Kbps]

WiBro Network Architecture II. WiBro Standardization (4/8) WiBro Network Architecture ■ PSS (Portable Subscriber Station) - Wireless access - IP mobility, Terminal/User authentication - Multicast service, Other network interworking ■ RAS (Radio Access Station) - Wireless Access - Radio resource management/Control - Handoff support - QoS support, Downlink Multicast ■ ACR (Access Control Router) - IP routing and Mobility management - Authentication/Security - QoS, IP Multicast, Billing support - Handoff control between RASs ■ Core Network - Authentication, Billing - IP Mobility support - Other network interworking Public IP Network IP Network of Operator HA AAA ACR RAS PSS

Standardization of major technology II. WiBro Standardization (5/8) Standardization of major technology IEEE 802.20 Mobile BWA flash-OFDM iBurst HSDPA MWA W-CDMA 3GPP IEEE 802.16e Mobile IS-95B cdma2000 1x EV-DV Mobile Wireless MAN cdma2000 1x 3GPP-2 cdma2000 1x EV-DO IEEE 802.15.1: Bluetooth IEEE 802.15.3a: UWB IEEE 802.15.3 HR IEEE 802.15.4 LR Wireless PAN IEEE 802.11a; HIPERLAN/2 NWA Nomadic IEEE 802.11 IEEE 802.11b Wireless LAN IEEE 802.11g FWA IEEE 802.16 Wireless MAN Fixed IEEE 802.16a/HIPERMAN 10k 100k 1M 10M 100M 1G * Not drawn to an exact scale

II. WiBro Standardization (6/8) IEEE 802.16 Evolution 802.16-2001 (10-66GHz) 802.16 a (2-11GHz) 802.16 d Revised Amendment 802.16 e (mobility) MAC PHY MAC + new PHY drop MAC ++ new PHY + Fixed Mobile

II. WiBro Standardization (7/8) IEEE 802.16d & 802.16e ■ IEEE 802.16d ■ IEEE 802.16e Network Model - Revision to 802.16, 802.16a, 802.16c - Licensed bands, 2~11GHz - Non line of sight (Practical) - Lower component cost • Good for residential and small-business - 30Mbps in 10MHz BW ■ IEEE 802.16e - Amendment to 802.16a/c/d - Licensed bands, 2~6GHz - Non line of sight - Support vehicular mobility - Main concern on handoff and sleeping mode

Korea decided IEEE 802.16e as WiBro Standard Baseline. II. WiBro Standardization (8/8) Roadmap of WiBro standardization TTA Korea decided IEEE 802.16e as WiBro Standard Baseline. (Jul. 2004) Phase I Phase I Rev. Phase II 2004.6 2004.10 2004.4Q ~ 2005.2Q OFDMA/TDD 1024 FFT, BW: 10MHz PHY Harmonization MAC Harmonization Enhanced PHY/MAC AAS, MIMO, LDPC, H-ARQ 802.16d/e 802.16d/e IOT Profile - Profile statement (2005.1Q) - Spec Work (2005.2Q) - Completion of Spec (2005.3Q) TTA TTA IEEE 802.16e Issue 802.16e/D5 Issue 802.16e/D6 Issue 802.16e/D7 Publish 2004.9 2005.2 2005.4 2005.3Q (?)

WiBro standard baseline and spectrum allocation III. WiBro Technology (1/4) WiBro standard baseline and spectrum allocation ■ WiBro system should satisfy IEEE 802.16-2004, IEEE 802.16e D3 above standard and 5 performance criteria Min data rate under 60km/h condition in cell edge: 512kbps (DL), 128kbps (UL) Bandwidth: above 9MHz Roaming between WiBro operators Frequency reuse factor: 1 Duplex: TDD including Tx/Rx time slot synchronization between WiBro operators ■ Spectrum allocation for WiBro service 2300MHz 2327 2331.5 2358.5 2363 2390 2400MHz CH1 CH2 CH3 1st Band 2nd Band 3rd Band GB WLAN 4.5MHz 10MHz

III. WiBro Technology (2/4) Key Features ■ RF Frequency: 2.3GHz ■ Multiple Access/Duplexing: OFDMA/TDD ■ Frame length: 5 msec ■ Bandwidth: scalable from 1.25MHz to 20MHz ■ Flexible subchannelization for band selection and diversity ■ Fast AMC (Adaptive Modulation and Coding) subchannel based on uplink CQI (Channel Quality Indicator) ■ Full diversity subchannel by multiple symbol grouping ■ Cell differentiation with different PN sequences ■ Pilot tone based downlink and uplink ■ Separate ranging channel time slot ■ More efficient channel code: convolutional (or block) turbo code ■ H-ARQ in the downlink and uplink ■ Modulation level: QPSK, 16QAM, 64QAM ■ Optional AAS (Adaptive Antenna System) support

III. WiBro Technology (3/4) System Parameters Parameter Value Channel spacing 9 MHz Effective bandwidth 8.75 MHz Number of used tones 864 out of 1,024 Number of data tones 768 Number of pilot tones 96 Tone spacing 9.765625 kHz Ratio of cyclic prefix time to basic OFDM symbol time 1/8 Basic OFDMA symbol time 102.4 μs Cyclic prefix time 12.8 μs OFDMA symbol time 115.2 μs TDD frame length 5 ms Number of symbols in a frame 42 TTG+RTG 161.6 μs

Average DL Data Throughput/sector Average DL Data Throughput/cell site III. WiBro Technology (4/4) System Capacity System Capacity Item Value Note Bandwidth Channel 9MHz Effective BW = 8.75MHz Total 27MHz 3 Channels Peak DL Data Rate 20Mbps Without AAS, MIMO Average DL Data Throughput/sector 6Mbps Multi-cell environments without AAS, MIMO Average DL Data Throughput/cell site 54Mbps ( = 6Mbps x 9) Macro cell site: 3FA/3Sector Cell Radius Macro Cell : 1Km Micro Cell : 400m Pico Cell : 100m 4 / 15

Subsystems & Service management system IV. WiBro Business Plan in KT (1/4) Logis WiBro Network UsN FPGA Macro-RAS micro-RAS Contents Partner Service Center Information Center Public Offices Portable Entertainment PCMCIA Tablet ACR Voice Internet Handheld Enterprise CF SmartPhone Command Control pico-RAS/ Repeater Smart/MIMO-RAS Home Network Chipset Subsystems & Service management system Mobile Internet Telematics e-Shop ITS Bank User terminal Network Service/Contents

IV. WiBro Business Plan in KT (2/4) Deployment Policy ■ Deployment by stages within three years ■ CAPEX reduction using currently operated wired/wireless infra (Backbone/Access network) ■ Minimization of shaded zone using repeater, WLAN/CDMA interworking Daejon Seoul Inchon Gwangju Ulsan Busan Daegu 2 Stage 3 Stage 1 Stage Deployment Plan Interworking Concept Hot Zone 2G/3G WiBro Hot Spot AP AP AP AP Park Airport

IV. WiBro Business Plan in KT (3/4) Terminal Policy ■ Various terminal (Card, Chip embedded Notebook, PDA, HPC, Smart phone etc.) ■ WiBro exclusive terminal (Easy access and User friendly interface) ■ Specific WiBro terminal interworking with existing services (WLAN, CDMA, DMB) Terminal Type Roadmap Phase 1 Phase 2 Phase 3 WiBro exclusive Terminal - Card - Embedded Multimode Terminal Card, Embedded type WiBro+CDMA+GPS etc. Specific Terminal - Person/Enterprise - Intelligence converged - Service specific One Chip Notebook WiBro exclusive Portable Terminal DBDM Terminal (WiBro+ CDMA) DBDM Terminal WiBro+ WLAN WIBro+ DMB WiBro+ GPS TBTM Terminal WiBro + WLAN + CDMA WiBro+ CDMA+ DMB PDA Smart Phone

WiBro Killer Application Existing Internet Service IV. WiBro Business Plan in KT (4/4) Service Strategy WiBro Killer Application Existing Internet Service ■ Development of killer application with multimedia/convergence type Main WiBro BMs are MMS, LBS, Game, Push service, IP Multicasting. ■ WiBro service interworking with existing services Wired Web Browsing, e-Mail: Information Movie VOD: Entertainment e-Stock, e-Banking, e-Learning etc. Evolution and Development service Main MMS (Multimedia Messaging Service) Hi-Quality Video Mail/Messaging Push Service Group video chatting, Ad & Coupon Game: IP based network game LBS (Location Based Service) IP Multicasting Service High-Quality VOD, Real Time Broadcasting, Movie Multimedia Convergence Wired/Wireless Wireless SMS VOD, Game: Entertainment e-Banking: m-Commerce Interworking service Nespot (WLAN) interworking service CDMA interworking service DMB interworking service Megapass (xDSL) interworking service