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National Communications Forum: Session T-01

National Communications Forum: Session T-01. Fundamentals of Broadband Access Session: T-01 Tuesday, October 17. Judith Hellerstein, President Hellerstein & Associates 2400 Virginia Avenue NW, Suite 1023C Washington, DC 20037 Phone: (202) 333-6517 Fax: (509) 355-9792

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National Communications Forum: Session T-01

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  1. National Communications Forum: Session T-01 Fundamentals of Broadband Access Session: T-01 Tuesday, October 17 Judith Hellerstein, President Hellerstein & Associates 2400 Virginia Avenue NW, Suite 1023C Washington, DC 20037 Phone: (202) 333-6517 Fax: (509) 355-9792 Judithh@jhellerstein.com www.jhellerstein.com

  2. Outline • What is Broadband? • Technology Drivers: The Shift Towards Data • Broadband Applications • Broadband Demand • Four Access Technologies • DSL, Cable Modem, Fixed Wireless, Satellite • Benefits of Broadband Access • Download and Performance Comparison Information

  3. What is Broadband? • DSL: 386K-7 Mb • Cable: Averages at 1 Mb • Fixed Wireless: 10Mb/s - 10Gb/s • Satellite: 300K- 2Mb Need is 10x to 100x higher bit rate than today’s offerings

  4. The Internet will be THE Information andCommunication Platform for the Future

  5. Technology Drivers: The Shift Towards Data • Strong Demand for Broadband access from Residential, SOHO, and Business • High speed Internet Access • Super-fast Web browsing • Almost instantaneous file downloading • Streaming video/audio • Voice over DSL • E-commerce • Distance Learning • Content Delivery

  6. Technology Drivers: The Shift Towards Data (continued) • Educational/Health Services • Work-at-Home • Telecommuting • Telephony • Small Office / Home Office • Teleconferencing • Remote video monitoring • Intranet • Internet • Other Business Applications, e.g., Voice over DSL • Remote LAN Access through VPNs • Demand for Hosted Applications

  7. Technology Drivers: The Shift Towards Data (continued) • Entertainment • Video services • Movies • Games • Additional Voice Lines • VoDSL

  8. 2003: Broadband Demand • More than 60% of all Internet access will be through broadband:DSL, Cable or Wireless • More than half of all broadband access will be through DSL • One in four users will be in smaller markets • Strong demand in small, midsize and semi-rural markets

  9. Four Access Technologies • DSL • Cable Modems • Fixed Broadband Wireless • Satellite

  10. Standards Based Access Solutions • Benefits of using a standards-based solution • Lack of standards leads to market fragmentation, low volumes, and high cost • Promotes interoperability of technologies and devices and leads to increased customer choice • Allows the market to provide more product and supplier alternatives than possible without a standard • Helps focus industry on resolving other challenges necessary to reach mass deployment • Lowers costs to suppliers and to consumers • Increases choice of providers and greater selection of products

  11. Interoperability • Interoperability is key, both among different technologies and among equipment providers • In each of the access technologies there are groups actively working on interoperability. • DSL: DSL Forum • University of New Hampshire’s Interoperability lab • Both UNH www.iol.unh.edu/consortiums/index.html and the DSL Forum, www.dslforum.org, hold frequent plugfests to test interoperability of equipment and technology amongst a large collection of companies in the same room • Open DSL Consortium • Cable: Cable Labs • Fixed Wireless: Wireless DSL Consortium • Interoperability is a critical first step in getting to certification • Service providers need to provide deployment models so that products can be tested and certified

  12. DSL Forum • DSL Forum Interoperability Working Group and the UNH Interoperability Lab hold frequent plugfests • G8 Interoperability Group 8, Members working to develop a long term framework for accelerating interoperability and providing leadership at ongoing plugfests • Developed a framework for facilitating interoperability and driving towards certification • Testing is currently taking place on an accelerated schedule

  13. Cable Labs • A non-profit research and development consortium that represents cable TV operators. Ongoing Projects include: • Cable Modem • DOCSIS Project defined the requirements for high speed access over cable modems • Open cable • Produced a series of specifications that define all next generation set-top boxes & other digital devices used by cable operators • Created a process & the facilities to test and certify for interoperability Open cable devices • Packet cable • A process for delivering interoperable specifications for delivering advanced real-time multimedia services over two-way cable plant • In-home networking

  14. Wireless DSL Consortium • New group formed in July 2000 and composed of Fixed Broadband Wireless equipment and chip manufacturers, system integrators, and service providers whose goals are: • To define, develop, and implement a set of open interfaces for MMDS products. • Enable quality of service control to the end-user • Improve Wireless broadband coverage to non line-of-sight customers • Create protocol specifications, interoperability standards, and validation methods for testing of new standard

  15. Spectrum Compatibility and Management • Along with Interoperability, Spectrum Compatibility and Management is a crucial issue that needs to be addressed for all access technologies • Development of spectrum compatibility standards is critical for DSL and is essential to reduce cross talk and other forms of spectrum interference

  16. DSL Flavors • Eight Flavors of DSL • Each flavor is dependent on: • The distance between the end user and the central office. • The DSL equipment used • DSL functionality is determined by the chipset that is included in the flavor offered.

  17. Standards Based DSL Variants • Standards Based DSL Variants • Asymmetric and Symmetric • ADSL and G.Lite • HDSL2 and G. Shdsl • Non-standards based DSL • RADSL, SDSL, HDSL, IDSL, and VDSL • Propreitary solutions • Nortel One Meg Modem • Paradyne’s Reach DSL

  18. DSL Flavors • ADSL • The most popular DSL technology. Can be either splitter or splitterless from 384k to 7 Mb • ADSL-Lite or G.Lite • A stripped down version of ADSL that was meant for consumers that offers a lower data rate • RADSL • Simply a name given to the rate adaptive feature built into the original ADSL standard • SDSL • A symmetric technology that is vendor specific and proprietary

  19. DSL Flavors (continued) • SHDSL • Emerging ITU standard (G.shdsl) • Spectrally compatible with ADSL and other technologies • Rate adaptive form of HDSL2 • Offers superior reach over a single copper pair. • Decision expected by Feb 2001 • Speeds from 324K to 2.3 Mbps. • HDSL • A vendor specific solution used mostly as a replacement for T-1 lines. • Requires 4-wires or 2 copper pairs

  20. DSL Flavors (continued) • HDSL2 • ITU decision on standard expected by the end of 2000 • An improved version of HDSL that requires only one copper pair and no line conditioning • Can be deployed out to 24,000 feet from the central office • ANSI standard symmetric solution that is spectrally compatible with ADSL • IDSL • ISDN based low bandwidth solution (144K). • Original choice of DLECs entering into the market. • Today used mostly for loops that are too far from the Central Office or are served through a Digital Loop carrier • VDSL • Very High speed DSL that provides ultra-high bandwidth for video delivery

  21. Cable Modems • Two way Broadband service provided through local cable operators • Three main cable Internet providers • @Home • Roadrunner • High Speed Access

  22. Structure of Networks • Cable networks designed as a tree structure: Branches of the tree — the pathways into the neighborhood Leaves — identifying individual households. • Pathways or neighborhood nodes support around 500 or less homes • Nodes can be split down further to ease congestion Regional Headends Primary Hubs Secondary Hubs 10-20 neighborhood nodes Fiber rings Fiber rings

  23. Cable Modem Speeds • Two-way cable modems provide downstream data rates from 2 to 10 Mbps over a shared connection • Speeds expected to climb to between 27 Mb and 34 Mbps. • Two way cable plant must have at least 550 MHz to transmit multiple advanced video and multimedia services. • Majority of upgraded cable plants have 750 MHz, or even 860 MHz to support multimedia services, including true video-on demand.

  24. Fixed Broadband Wireless • Wireless Access refers to delivering services using radio waves rather than copper, fiber, or coax cable. • Can be used as a “last mile” technology for a network that uses coax and/or fiber cables. • Services available include • Digital info such as voice, video, and data • Broadband access similar to ADSL • Extensions of the PSTN or VPN • Wireless local loop

  25. Fixed Broadband Wireless Technology • Technology used to deliver wireless access: • Point-to-point • Point-to-multipoint • Allows high speed, high capacity two way multimedia service to be delivered quickly to consumer. • Fixed wireless access uses spectrum between 24-42 GHz • ATM air interface supports voice, data, and video services • Bandwidth shared among users in a cell • Bandwidth applications from 64K to 155 Mb

  26. Frequencies • Frequencies available for delivering broadband • Spectrum used is typically above 2 GHz • Lower frequencies — often used for mobile applicationsHigher frequencies — often used for fixed wireless access • Fixed Wireless technologies include: LMDS, MMDS, and DEMS • Fixed wireless spectrum lies between 24-42 GHz • Both Licensed and unlicensed bands are available • Unlicensed: 2.5, 5, 18, and 60 GHz bands (ex. Metricom’s Ricochet) • Licensed: 2.6, 24-26, 28-30, and 38-40 GHz bands

  27. Fixed Wireless Broadband Access: Providers and Target Markets • Teligent • Winstar • Advanced Radio Telecom • AT&T’s Project Angel • Sprint • WorldCom • Target Markets • SOHO • Small Business • Medium Business

  28. Benefits of Fixed Broadband Wireless • Provides bandwidth and access speeds equal or greater than ADSL or cable modems • Can extend the reach of fiber or coax by providing the “last mile” of the network • Fast market entry for service providers as compared to wired systems • Low startup and entry costs • Pay as you go approach: carriers only required to add equipment as the number of users grow • Operator control over facilities • Flexibility of deployment, especially in medium--high population densities where penetration rates are initially low

  29. Challenges • Overcoming line-of-sight limitations • Broadband wireless technology not as well understood as broadband wired technologies • Although spectrum is available, equipment is not readily available • Technology for the higher frequencies is just now coming to market • Lack of any high volume production of equipment needed • 155 Mb modems are only produced in low-volume, high-cost production • Technology for low-cost, high speed burst modems is available but systems have not been produced.

  30. Satellites • Geostationary (GEOs) satellites have a line of sight to almost every location • Low earth orbit (LEOs) multi satellite systems have a line of sight to every location above ground • Two way Satellite systems are just being launched • Current data access uses the Ku band of spectrum • Future broadband access will be provided through the use of the Ka band of spectrum • Broadband access through Ka spectrum have only been tried in labs and thus is untested and unproven. Best examples are Teledesic and iSky

  31. Satellite Providers • Tachyon.net offers three different levels of service • 300K, 800K, and 2Mb • Services sold through ISPs • Gilat-to-Home • Planned deployments by end of the year through VSATs • 40Mb outbound, 150K inbound (shared) • Hughes • DirectPC offers a one way broadband service

  32. Benefits of Broadband Access • High Speed “always on” connections to the Internet • Cost-effective • Less expensive to deploy than fiber, frame relay, or T-1 services • Operates over ordinary 2-wire phone lines • Does not require huge upfront costs • Users can be added incrementally • Workers no longer need to be located on site to gain access to corporate LAN • No waiting for connection or busy signals • Faster time to market

  33. Bandwidth Requirements for Broadband Applications

  34. Download Comparison

  35. Performance Comparison

  36. Conclusion • Data traffic demand is driving access market to provide high-capacity transport • Limitations of Fiber/DSL technology are driving the broadband wireless industry • Cost-effectiveness of broadband access • Great market potentials

  37. Questions, Comments, Suggestions? Judith Hellerstein, President Hellerstein & Associates 2400 Virginia Avenue NW Washington, DC 20037 Phone: (202) 333-6517 Fax: (509) 355-9792 Judith@jhellerstein.com www.jhellerstein.com Thank You

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