Wireline Technologies

Scott AndersonGabriel KiraguAaron MillerSunit Tailor

Presentation Overview

• Local Access Wired Broadband Technologies - Scott

• Carrier Backbone Transmission Networks – Sunit

• All Optical Networks – Aaron• International Networks – Gabriel

Local Access Wired Broadband Technologies

• Introduction• The Market - Small to Midsize Businesses and

Consumers• The need for more information - faster, cheaper,

better.• Dial up to slow - T1 expensive.

• Speed measured in kbps, mbps and gbps.• Works with existing physical media-reduced start up

costs.• Most businesses and households have at least one

telephone or TV cable line.

Local Access Wired Broadband Technologies

• Digital Subscriber Line(DSL)• Coaxial Cable

Terminology Primer

DSL

• Developed in 1989 for the telephone industry.• Video on Demand(VOD) was viewed as the

telephone industry’s way to compete with cable television providers.

• Originally designed to handle high downstream rates for streaming video.

• Telecommunications Reform Act of 1996. • The Internet explosion.

Broadband on Twisted Pair

• Voice, upstream, downstream.

DSL

• Working with the “local loop”(a.k.a. -”The last mile”, or “The last leg”)

Typical DSL Setup

DSL Flavors

DSL Comparison

DSL

• Uses existing twisted pair• Cost effective• Good and bad

• In 1989 FCC Estimated That U.S. had 179,822,123 Local Loops.

• Copper Corrodes• Cross talk

• Distance sensitive• Works within a proven and reliable

infrastructure(Usually)• Doesn’t work over fiber or amplified voice lines

Current Trends

• DSL subscribers estimated to be over 3,000,000 today, increasing to over 14,000,000 by 2004.

• DSL providers are provisioning at ever increasing rates and…...

• DSL providers are filing for bankruptcy at ever increasing rates.

• Examples: Covad, Inc, Rhythms Comm., NorthPoint Comm.

Independent DSL ProvidersCOVAD, INC.

• Filed Chapter 11 in August of this year.• The First Of the Independent DSL Providers.

• Dealing with Major Business Issues to Survive.• Must Change Business Plan.

• Wholesaler• Partnered with (Competitive Local Exchange Carriers

(CLECS) and Internet Service Providers(ISPs).• Acquisition Costs High.• Competition from Incumbent Local Exchange

Carriers(ILECS).• Poor service

DSL

• ILECS will continue to expand this segment. • VODSL• Increasing competition

DSL Competition

Coaxial Cable

Coaxial Cable

• Invented in 1929 and first used commercially in 1941 by AT&T.

• Designed to broadcast one signal to many receivers.

• Half-Duplex infrastructure, however providers have been replacing with Full-Duplex for two streams.

• The Internet explosion.

Broadband Cable

Typical Cable System

Cable Broadband

• 75,000,000 Cable TV Subscribers.• Over 3,500,000 Broadband users.

• Shared Bandwidth• Current technology allows a Downstream rate of

about 30-40 Mbps, Upstream about 8Mbps which can be shared with 500-2,000 users.

• Requires Signal amplification• Some providers have up to 6, increasing likelihood of

mechanical failure

Cable Broadband

• Investing heavily in Fiber.• Reduces signal amplifier needs.

• Fiber being placed close to the user(Node).

Typical HFC Network

Narad Networks

“In my mind true broadband begins at100 Mbps.”

CEO Dev Gupta

Narad Networks

• In business since July 2000, initial funding of $49,000,000.

• Optic Network Switches at the fiber node level.• First generation solution offered 1 fiber per node (200-500

homes) with 100 Mbps drops.• Second Generation will offer a 50 home node 200 Mbps drops.

• Software operating system that handles creation, management and billing interconnection.

• Voice over Internet Protocol(VOIP).• Network Storage

Sources

www.paradyne.com “The DSL Sourcebook” www.zdnet.com “How ADSL works” www.privateline.com “Telecommunications Fundamentals” www.dsl.net www.ericsson.com “Cable Modems-Broadband Highway to the Home” www.dslreports.com www.howstuffworks.com www.xchangemag.com “GHDSL Hits the Streets” www.cabledatanews.com www.business2.com “Covad-Is DSL Headed for a Meltdown?” www.dslforum.org www.broadbandweek.com www. sbdepot.com “The Downfall of DSL Providers” www.dslprime.com www.networkmagazine.com “The Last Mile Today” www.2wire.com www.netaction.org “Are DSL Users Satisfied with their Service?” www.wired.com “DSL Behind the Broadband Race” www.nswc.navy.mil “Cable Modems and Hybrid Fiber Coaxial Systems” www. Covad.com www.novadnetworks.com PWC “Technology Forecast: 2001-2003 PCMagazine November 7, 2000 “Know your DSL” www.sanfrancisco.bcentral.com “Covad to File for Bankruptcy”

Carrier Backbone Transmission Networks

Market Growth Impact on Carrier Backbone Networks

• Excessive bandwidth demand boost in the bandwidth capacity.• DSL and Cable Modems to the masses• Explosion in corporate and residential reliance on the

Internet

• Voice-centric --------> Data-centric US Network Traffic Data Traffic Overtakes Voice

Traffic

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Options for Increasing Carrier Bandwidth

• Increase the Bit Rate• Time-Division Multiplexing (TDM)

• Increase the Number of Wavelengths• Wavelength Division Multiplexing (WDM)

Line and Network Speeds (Gbits/s)

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Optical (WDM)

TDM

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Time Division Multiplexing• TDM increases the capacity of the transmission

link by increasing the number of bits transmitted per second

• SONET / SDH• Standards for Optical transport of TDM

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Transm ission link(2.5 G bps x 3 = 7.5 G bps)

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TDM

• Bi-directional line-switched rings (BLSRs)

TDM

• SONET / SDH Drawbacks• No Priority algorithms• Multiplexing Hierarchy is a rigid one• Slots for input is reserved even when there is no data

to send• Can not carry multiple protocols without a common

signal format• Inefficiency in carrying data traffic.

Bit RateEthernet

10 Base-T (10 M bps)

100 Base-T (100 M bps)

1000 Base-T (1000 M bps)

SONET/SDH Signal

STS-1

STS-3/STM -1

STS-48/STM -16

51.8540 M bps

155.520 M bps

2488.32 M bps

W asted Bandwidth

80.709%

35.699%

59.812%

Metropolitan Area Optical Alternatives

• 10 Gbps Ethernet and Resilient Packet Rings• The inherent bandwidth waste by BLSR • Early trials were conducted by running 10 Gbps

Ethernet on OC-192 rings without SONET protection switching.

• IEEE802.17 - Resilient Packet Rings Group, Internet protocol Over Packet Transport Rings

• Cisco’s Dynamic Packet Transport - Layer 3 route restoration network

• destination stripping• replace all SONET Automatic Protection Switching with

Intelligent Protection Switching• Fairness algorithm (SRP-fa) is used to avoid congestion

Wavelength Division Multiplexing (WDM)• WDM assigns incoming optical signals to specific

frequencies of light within a certain frequency band.

• DWDM spaces the wavelengths more closely than WDM and therefore has a greater overall capacity.

Independent b it ra tes and form ats

W D M

DWDM

• SONET with DWDM• SONET multiplexing equipment can be avoided

altogether by interfacing directly to DWDM equipment from ATM and packet switches.

• DWDM Eliminates Regenerators

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DW DM Transm ission - 10 G bps

Conventional TDM Transm ission - 10 G bps

Improvements in DWDM Systems

• Wavelength Switching• Lucent’s Ultra-Dense Wavelength Division Multiplexin

g (UDWDM) Systems, which offers 100 Or more wavelengths

• Tunable filters• Optical switches• Wavelength converters• Tunable lasers• Integration with packet switching equipment

DWDM

• Advantages• Capital cost savings when expanding bandwidth• Enables incremental growth of bandwidth• Reduced time needed to install additional bandwidth

• Limitations• Depending on the type of fiber in place, the fiber’s

optical characteristics might limit the ability to use DWDM

• System performance and configurations are vendor dependent

• Standards for DWDM do not yet exist

Other Advances in Optical Communications

• Capacity Improvements• L band (1,570nm to 1,620nm) with or instead of the C

band(1,530nm to 1,562nm), S band (1,450nm to 1,520nm) will available in 2002 and 2003.

• Lucent announced several 40 Gbps component products, including an optical receiver in 1999 and 2000.

• Corning introduced its third-generation Leaf fiber in August 2000 which reduces the amount of polization mode dispersion by 50 % over second generation Leaf fiber.

• Inside of a fiber optic cable can carry more fibers. New cable designs can hold up to 1,152 fibers.

Other Advances in Optical Communications• Range Improvements

• EDFAs - Erbium-doped fiber amplifierS• These requires depositing the rare earth element

erbium in to the fiber itself by a process called doping.• Extend the reach of an optical signal to thousands of

kilometers without using electronic regenerators and used in most newly installed transoceanic cable systems

• Raman amplification• The transmission fiber is pumped with very high optical

power (by adding light unrelated to the signal).• Corning offer Raman amplification with EDFAs to

increase the range of terrestrial transmissions and transoceanic fiber optic links.

Main players in Optical Networks

• Lucent• Nortel Networks

References• Technology Forecast: 2001-2003

Mobile Internet: Unleashing the power of Wireless• http://www.lucent.com/products/category/0,,CTID+2006

-LOCL+1,00.html• http://www126.nortelnetworks.com/products/index.html• http://www.cisco.com/warp/public/cc/pd/rt/12000/dptlc/i

ndex.shtml• http://www.techfest.com/networking/wan/sonet.htm• http://www.cisco.com/univercd/cc/td/doc/product/mels/d

wdm/• http://www.lucent.com/knowledge/documentdetail/0,14

94,inContentId+8815-inLocaleId+1,00.html

References• http://www.lucent.com/minds/trends/trends_v4n2/page3

.html• http://www126.nortelnetworks.com/products/mt150251_

tunable_filter.html• http://www.corning.com/photonictechnologies/publicpag

es/news&events/pr/daisy0916_pr.htm• http://www126.nortelnetworks.com/products/ml20_vcsel

_tunable_laser_tu.html• http://www.corning.com/photonictechnologies/

publicpages/photonicsoverview/productleadership.htm• http://www.corning.com/photonictechnologies/

publicpages/news&events/pr/pr031201.html

All Optical Networks

What is an All-Optical Network?

• Optical fibers connecting locations many miles apart that carry information in the form of on-off flashes of laser light.

• Speed depends upon how fast the laser flashes on and off.

• The average speed is 10 Gigabits per second.• Used to connect countries and major cities

throughout the world.

Problems with current Electrical to Optical Networks

• Complexity• Transforming an optical signal to an electrical signal

• Increase expense• The price is high to perform the conversion

• Reduced bandwidth• It takes time to perform the conversion

Advantages of All-Optical Network

• Greater Throughput• Increased amount of data traveling down the wire

• Better price/performance• The increased performance justifies the price

• Smaller physical footprint• Smaller in size

• Better bandwidth utilization• Multiple channels can be used by a single optical line

All Optical Networks, INC

• Founded in 2000• Focused on providing the telecommunications

industry with the highest performance possible for the transmission, routing, and storage of information in optical networks

• http://www.alloptical.net/

Technological Developments

• Optical add-drop multiplexers (OADMs)• Allows the signal to remain in the optical photon

form• Reduces the complexity of conversion

• Optical cross-connects (OXCs)• Route network traffic to the proper destinations• Again reduces the complexity of conversion

Inside an optical cross-connect

Optical cross-connect example

Marconi

• One of the worlds leading telecommunications companies in the world.

• Present in 140 countries• 4.5 billion dollar turnover• http://www.marconi.com

Optical Internetworking Forum (OIF)

• Formed by Cisco Systems and Ciena Corporation on April 20, 1998

• An open forum focused on accelerating the deployment of optical networks

• Provides a venue for people interested in working together to resolve issues and develop specifications

• http://www.oiforum.com

Optical Internetworking Forum (OIF)

• Developed five specifications for optical networks:

• System Packet Interface 3 – a router interface at 622 Mbsp and 2 Gbsp based on packet over SONET

• System Packet Interface 4 – a router interface at 10 Gbsp based on packet over SONET

• System Framer Interface – electrical interface and clock specification

• Very Short Reach Interface – 12 fiber 850nm• Very Short Reach Interface – 1 fiber 1310nm

Tends within Optical Networks

• SONET/SDH interfaces on switches and routers• All-optical label swapping

• A new signaling and traffic-engineering approach for photonic packet switching

• ITU 100 Ghz grid• Increases from 50 Ghz• Allows larger wavelengths to travel through the

network

References• http://www.alloptical.net• http://www.lightreading.com• http://www.marconi.com• http://optical-networks.com/nov01_abstracts.html• Technology Forecast: 2001-2003,

PriceWaterhouseCoopers, PWC Technology Center, Menlo Park, CA, April 2001