trends in hybrid fiber-copper access … · ftth (ct: 100m for 100m by 2015) ... alcatel-lucent...

COPYRIGHT © 2014 ALCATEL-LUCENT. ALL RIGHTS RESERVED.

Jochen Maes, Broadband Innovation, Bell Labs Alcatel-Lucent Keynote @ IEEE Globecom Standards Workshop, 2014

TRENDS IN HYBRID FIBER-COPPER ACCESS NETWORKS

2


1988

1989

1988

FTTH THE NEXT BIG THING SINCE DECADES

Kudelka

Delays and unexpected cost increase due to • Difficulties in mobilizing a large workforce • Delays in finalizing agreements among parties involved • Network turned out less fiber-ready than expected

3


REALITY: GRADUAL EXPANSION OF THE FIBER NETWORK

Fiber Copper

ADSL2+

VDSL2

Vectored VDSL2

G.fast

≈ 10−20 Mb/s

≈ 20−50 Mb/s

≈ 100−150 Mb/s

≈ 0.5−1 Gb/s

< 5 km

< 2 km

< 1 km

< 250 m

Time

Vectoring

Vectoring

XG-FAST ≈ 5−10 Gb/s < 50 m

Vectoring

Leverage legacy network for rapid nation-wide service upgrades

4


BROADBAND OVER A HYBRID FIBER-COPPER NETWORK

1

10

100

1000

10000

1995 2000 2005 2010 2015 2020

ADSL ADSL2

ADSL2+ VDSL(2) 8b

VDSL2 17a + bonding

+ vectoring

G.fast 106MHz

G.fast 212MHz

+ bonding & vectoring

1 Mb/s

10 Mb/s

100 Mb/s

1 Gb/s

10 Gb/s XG-FAST


DRIVERS FOR BANDWIDTH

Applications

Competition

Regional incentives

6


ACCESS NETWORKS AROUND THE GLOBE CONTINUOUSLY NEED TO TRANSFORM TO KEEP UP WITH BANDWIDTH DEMANDS

Australia NBN 100M for 90% by 2020

China 12th 5-year plan FTTH (CT: 100M for 100M by 2015)

India National Backbone Broadband for 90% by 2013

EU Digital Agenda 30M for all, 100M for 50% by 2020

Connecting America FCC National BB plan

100M for 100M by 2020

New Zealand UFB 100M for 75% by 2020 Brasil Plano Nacional

100 Mb/s tier driven by national incentives


GRADUAL FIBER DEPLOYMENT

CO deployment FTTCab

CO CO mini DSLAM

passive cross-connect

cabinet

8


VDSL2 VECTORING CONCEPT

COPPER PAIRS INTERFERE WITH EACH OTHER, REDUCING

BITRATES

Vectoring performance

Vectoring = noise cancellation headphones for your copper plant

9


G.VECTOR: CROSS-WHISPERING

0 5 10 15 20 25 30-160

-140

-120

-100

-80

-60

Frequency (MHz)

Rec

eive

d po

wer

(dB

m/H

z)

99% worst case model

SNR Received signal

Received crosstalk

Modem noise floor

Transmitter Channel Receiver

Non

-vec

tore

d Ve

ctor

ed

XTALK Noise cloud

Transmit signal Receive

signal

10


12 2011

6 2012

9 2012

12 2012

3 2013

6 2013

9 2013

12 2013

3 2014

6 2014

9 2014

12 2014

3 2012

BBWF 2012 6 CUSTOMER 20+ TRIALS

90K VECTORING LINES

BBWF 2013 17 CUSTOMER

55+ TRIALS 2.4M VECTORING LINES

1st nationwide VDSL2 vectoring activation

connects 1st user with VDSL2 vectoring

ALU 1st to announce vectoring product

9 2011

ADSL since B 1998

VDSL2 since M 2005

Vectoring since E 2011

ALCATEL-LUCENT SHIPMENTS [MIO LINES]

VECTORING IS ON THE RISE HELPS OPERATORS GET MORE FROM THEIR DSL COPPER NETWORKS

BBWF 2014 25+ CUSTOMER

65+ TRIALS 9.4M VECTORING LINES


GRADUAL FIBER DEPLOYMENT CONTINUES

CO deployment FTTCab FTTdp

CO CO mini DSLAM

CO micro node

passive cross-connect

cabinet

12


G.FAST: CROSS-SHOUTING

• Channel no longer diagonally dominant • Power constraints must be met • Alternatives to linear zero-forcing become interesting

0 20 40 60 80 100 120 140 160 180 200-140

-130

-120

-110

-100

-90

-80

-70

Frequency (MHz)

Rec

eive

d po

wer

(dB

m/H

z)

SNR

Received signal Received crosstalk

Modem noise floor

Transmitter Channel Receiver

XTALK Transmit signal Receive

signal

Transmit signal above PSD mask

=

3

2

1

333231

232221

131211

3

2

1

uuu

PPPPPPPPP

xxx

Precoder Transmit signal

User signal

Power of user signal

Power on line

M. Guenach, et al., IEEE Globecom 2014

13


VECTOR 2.0

Large crosstalk Impact: gain scaling,

discontinuous operation, non-linear precoding.

Aggregate data rate Flexible (dynamic?) allocation to

down or up

0 50 100 150 200 2500

200

400

600

800

1000

1200

1400

1600

1800

2000

2200

Loop length (m)A

ggre

gate

dat

a ra

te (M

b/s)

2.3 to 211.9 MHz no XT 2.3 to 105.9 MHz no XT17.7 to 105.9 MHz no XT17.7 to 105.9 MHz with XT

The numbers are in • Trials show huge impact of crosstalk • And huge benefit of Vector 2.0 • High variability in cable quality, both single

user and crosstalk

Rate/reach • G.fast cable model (CAD55) • One 99% worst case crosstalker

MEASURED SIMULATED


FTTDP ARCHITECTURE

G.fast transceiver

Power extraction

60 Vdc Power insertion

DPU power supply unit

G.fast transceiver

Power source

Aggregation

Passive splitter DPU

CPE

DPU

DPU can be powered from the customer premises ETSI TM6 101548 CPE powered network equipment

ITU-T 150 Mb/s vectored VDSL2 17a (250 Mb/s with 30a) 1 Gb/s G.fast

1 to 48 users per remote network equipment

(X)GPON, P2P, copper backhaul BBF WT-301 FTTdp

15


REVERSE POWERING

•Persistent Management Agent (PMA) •DPU with dying gasp •Distribution point managed using Yang data modeling language of the NETCONF L2 protocol

DPU

Management element

PMA

NETCONF YANG

Reverse power

Single line power use

Maximum power use

power that can be delivered with reverse powering

power consumption as function of # active lines

A B

G.fast gateway Subtending node

DPU

unused copper pairs

fiber

Forward Reverse

Local

Max power injected at CPE

Loop length

Max power received at access node

example line

DISCLAIMER: indicative figures,

not product specification

C

Timmers et al., IEEE ICC 2012 – workshop from reasearch to standards

17


652 MBit/s US+DS TRAFFIC (74m in-house cable)

Source: A1 in cooperation with ALU

18


G.fast on twisted pair in overlay with VDSL2 17a G.fast equally works on coax!

G.fast end frequ configured to 65 MHz to avoid interference with CATV signal

Source: BT Labs in cooperation with ALU Source: test by ALU in operator lab

G.FAST GIVES HUNDREDS OF MBIT/S OVER LEGACY TWISTED PAIRS ALSO WORKS ON COAX

19


G.FAST OFFERS CONTROL OVER UP/DOWN BIT RATE RATIO

• G.fast makes use of Time Division Duplexing allowing a flexible configuration of the upstream / downstream ratio

• All G.fast lines in the same cable need to be synchronized, with the same up/down split

- In presence of crosstalk

DS DS US

MUS MDS

time

TDD frame (e.g. 750µs)

US US

Source (bit rate figure): Orange Labs in cooperation with ALU

20


Bit rate loss may increase if multiple bridged taps

bridged tap 2m, 10m, 20m

100m

Source: ChuangHwa Telecom Labs (CHT-TL) in cooperation with ALU

BT length DS loss US lossno 0% 0%

20m -6% -5%10m -6% -4%2m -13% -8%

G.FAST ALLOWS FOR END-USER SELF-INSTALLATION SOME (MODEST) BIT RATE LOSS IN CASE OF BRIDGED TAPS IN-HOUSE

21


G.FAST ALLOWS CO-EXISTENCE WITH VDSL2 AND RADIO SERVICES

• ITU-T G.9700 specifies power spectral density (PSD) mask requirements for G.fast and a set of tools to reduce the transmit PSD mask for compliance with:

- Regional requirements

- Operator requirements e.g. spectrum compatibility and coexistence with other xDSL access and home network technologies

- Radio services

- EMC requirements

G.fast start frequency (e.g. 23 MHz) for compatibility with VDSL2 in same cable

E.g. spectral notches or tone masking for protecting sensitive radio bands

DS bit rate loss due to skipping bands: ~10% (e.g. 558 Mb/s 500 Mb/s)

Source (PSD figure): BT Labs in cooperation with ALU

22


GRADUAL EXPANSION OF THE FIBER NETWORK

Fiber Copper

ADSL2+

VDSL2

Vectored VDSL2

G.fast

≈ 10−20 Mb/s

≈ 20−50 Mb/s

≈ 100−150 Mb/s

≈ 0.5−1 Gb/s

< 5 km

< 2 km

< 1 km

< 250 m

Time

Vectoring

Vectoring

XG-FAST ≈ 5−10 Gb/s < 50 m

Vectoring

23


HOMES PASSED FIBER NETWORK HOMES CONNECTED COPPER NETWORK

Aggregation

SDN control

PMA

Fiber backhaul

Distribution Point Unit • Single or very few subscribers • Very close to end user

Reverse powering • User doesn’t need to power shared hardware • Short cables have low resistive loss

Multiple pairs per subscriber • No/little inter-user crosstalk • High intra-user crosstalk

24


over 2 pairs

over 1 pair

CAT5e

CAT5e

operator cable

operator cable

Single pair

LEOPARD XG-FAST PLATFORM WORLD RECORD SPEEDS

W. Coomans et al., IEEE Globecom 2014, workshop From Research to Standards.

2 pairs available

25


SPEED UP ADOPTION OF ULTRA BROADBAND SERVICES THROUGH HYBRID FIBER-COPPER NETWORKS

FTT… NODE CURB MANHOLE POLE DRIVEWAY FRONTDOOR BUILDING

>200 METER >100 SUBSCRIBERS <200 METER

10s OF SUBCRIBERS 10s OF METERS 1 SUBSCRIBER

XG-FAST G.fast VDSL2 VECT

trends in hybrid fiber-copper access … · ftth (ct: 100m for 100m by 2015) ... alcatel-lucent...

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