Dynamic Spectrum Managementthe path to Gbps DSLs/ future of copper

FCCVia video conferenceNovember 19, 2009

111/19/09

John M. CioffiProf Emeritus, Stanford U

Chairman and CEO, ASSIA Inc.

Broadband is DSL !

• DSL is largest fraction (over 70% of broadband)– And growing faster (even fiber connects are VDSL)– It costs a lot less

11/19/09 FCC 2

360M in 2012

Many are FTTBWith VDSL to customer

Source: Point Topic

How Fast is Copper?

• 10 Gbase-T is 2.5 Gbps/pair – at 100m on category 6 twisted pair

11/19/09 FCC 3

• 150Mbps – 500Mbps DSLs demonstrated– 100m on category 3 twisted pair

• Ubiquitous100Mbps to 1 Gbps DSLs?– Dynamic Spectrum Management (DSM)

• Soon, cheap, and energy efficient

• And, a lot of signal processing

4

Technical Challenges in DSL

• Changing environment– with daily DSL usage patterns– with daily appliance usage patterns– with customer adds and drops– with construction in the community

Crosstalk

Core Network

DSLAM

Radio Interference

Copper Impairments

In-home Interference Noise and interference

● interference from in-home sources● interference from outside sources● interference from other DSL lines● wiring problems (in-home and outside)

11/19/09 FCC

5

Basic DSM functions today

• DSM Improves– Operations cost– Data rate versus Length– Power consumption

Diagnostics Loop

Diagnostics● copper● DSL

Upgrade ident.

OSS, customer care

Reprofiling Loop

Automatic line repair

● QoS target● rate target

Daily collection from all lines

DSLAccessNetwork

FCC

FCC 6

DSM Unlocks xDSL Potential

25

50

75

100

125

2009 2010 2011 2012

DSM I- single line data & control

DSM II- multi-line data, single line control

DSM III & G.vector- multi-line data & control

DSL Potential

DSM server/software

- stability- diagnostics

- mgmt of power, - apps, crosstalk

- vectored- xalk cancel

CPE Noise Cancellation

- active noise cancellation- premises-based diagnostics- standards compatible, but independent

Date

Mbps

DSM Level 1 Example (23M+ today)

3%

47%

29%

19%

Dnstrm Rates Before DSM

14%

24%

21%

19%

11%

13%

Dnstrm Rates After DSM

Above 14.5Mbps

12~14Mbps

10~12Mbps

7~10Mbps

5.7~7Mbps

Below 5.7Mbps

40%

23%

16%

13%

8%

Stability Before DSM

61%

29%

3%1%5%

Stability After DSM

CV<=50 and Retrain<=0CV<=250 and Retrain<=1CV<=1000 and Retrain<=2CV<=5000 and Retrain<=3Others

• DSM Level 1 is deployed on– 17M lines in USA

• Will approach 30M by YE2010– 6M DSLs in Europe

• Will exceed 15M by YE2010

11/19/09 FCC 7

17a 998 Downstream - worst case data rate - 50 users

0

25

50

75

100

125

150

175

200

225

250

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

Loop Length (Meters)

Dow

nstr

eam

Dat

a Ra

te (

Mbp

s)

non-bonded 47 cancel min Bonded 47 cancel min Non-bonded 0 cancel min

Level 3 DSM: ITU G.993.5 VDSL2+

Vectoring - 1 pair

Bonding+Vectoring

Single-pair,No vectoring

• 100-pair Telco cable, 4x25-pair binders (NIPP-NAI model)• Does not include Telco cross-box, so gains may be larger!

EuropeResidential

North AmericaResidential

11/19/09 FCC 8

Bonding “GDSL” – 4-pair drop

7766

5544

3322

1100

0 100 200 300 400 500 600 700 800 900 10000.5

1

1.5

2

Cable Length in meters

Dat

a R

ate

in G

bps

Symmetric Data Rate vs Cable Length for 4 twisted pairs as a MIMO Channel 35 MHz band plan, 21 dBm aggregate power (US and DS combined), -150 to -140 dBm/Hz linear noise increase, Coding gain 6 dB

Bit cap = 20

1.0G

1.5G

3000’1500’

• Up to 7 channels• 30MHz

11/19/09 FCC 9

The DSM Opportunity• Dynamic Spectrum Management (DSM)

– Path to 100+ Mbps VDSLs and/or ADSL2+ • DSM Level 1 – line stability in use now worldwide• DSM Level 2 – politeness (higher speeds, lower power) - beginning• DSM Level 3 – “G.vector” – 100+ Mbps VDSLs

– Bonding of multiple lines, etc.

• DSL is global wire-line revenue growth vehicle • Major opportunity for new services triple/quadruple play• Video (IPTV, video-phone, You Tube)• Dual-Wifi (and/or Femto-cells) fed by DSL

Level 11$/line-mo Level 2

3$/line-mo Level 3> 10$/line-mo

11/19/09 FCC 10