gerard kuyt

InternationalElectrotechnicalCommission

Trends in FTTH / FITH Optical Fibre & Cable and associated standardization

Gerard Kuyt*, Alain Bertaina, Martin Davies

Prysmian Group

*) ITU-T Editor Rec. G.652 + G.657Chairman of IEC SC86A

FTTH Conference 2013 – LondonWorkshop: Standardization


2

Contents:Introduction ITU-T SG15 / IEC SC86A

Evolution optical fibre technology

�� Overview ITU-T Recs. & IEC Fibre Standards

Constraints in FTTH Access & MDU

�� Rec. G.657 BI-SMF

Solutions for Access / Drop & MDU cabling

�� Examples FTTH Roll-out Cost Saving (Out-/Indoor)�� References to associated standardization

Current Discussions in Standardization

Conclusions

FTTH Conference 2013, London, 2013-02-19

Trends in FTTH / FITH Optical Fibre & Cable and associated standardization


3

Introduction ITU-T SG15 / IEC SC86A

ITU-T SG15Optical transport networks and access network infrastructures


SC86BInterconnecting

Devices & Passive

Components

SC86 Fibre Optic Systems

& Active Devices

WG3

Opt. Cables

TC86

Fibre Optics

SC86A

Fibres & Cables

WG1

Opt. Fibres

IEC TC86/SC86A


4

Evolution Optical Fibre Technology

Dispersion-modified single-

mode fibres

DSF: G.653

3rd Phase

65 70 75 80 85 90 95 2000 05 10

1966

Kao’Prediction

1970

20 dB/kmbreakthrough

WDM systems (DWDM, CWDW)

Advent of OFA

1989

Multimode fibresMM-Fibre

SIMM-Fibre

GIMM-Fibre G.651

SMF: G.652.DDispersion-unshifted single-

mode fibres

Sin

gle

-mode

fibre

s

SIMM: Step-Index multimode fibreGIMM: Graded-Index multimode fibreCSF: Cutoff shifted single-mode fibreBIF: Bend-Insensitive single-mode fibreNZDSF: Non-zero dispersion shifted SMFN-NZDSF: New NZDSFDCF: Dispersion compensating SMF

BIF: G.657

G.651.1

SMF: G.652.A

CSF: G.654

1st Phase

2nd Phase

DCF: -----

NZDSF: G.655

4th Phase

N-NZDSF: G.656

5th Phase

Credit to Dr. Ohashi, Osaka Prefecture University

Internet bubble

Single channel systems



5

Evolution Optical Fibre Technology

Optical communication resulted in ‘silent’ revolution: the global information age (internet, social media), turning the world into a ‘village’


8 What’s the next step? Space Division Multiplexing?

Source: OFC’12, S. Bigo, Alcatel-Lucent Bell Labs


6

Current Single-Mode Fibre Categories

ITU-T Recs. G.65x / IEC Bx

ITU-T Description (cabled fibre) CreatedLast

editionTables IEC Fibre category (60793-2-50)

G.652.AG.652.BG.652.C

G.652.D

G.653.A B2_a

G.653.B B2_b

G.654.A -G.654.B B1.2_bG.654.C B1.2_cG.654.D -G.655.A -

G.655.B -

G.655.C B4_c

G.655.D B4_d

G.655.E B4_e

G.657.A1 B6_a1

G.657.A2 B6_a2

G.657.B2 B6_b2

G.657.B3 B6_b3

Bending loss insensitive fibre

G.652Characteristics of a single-mode

optical fibre and cable1984

G.656G.656

Characteristics of a bending loss

insensitive single mode optical

fibre and cable for the access

network

G.657 2006 Nov. 2012

G.655

G.654

Nov. 2009

Characteristics of a fibre and cable

with non-zero dispersion for

wideband optical transport

2004 July 2010

G.653

1988

July 2010Characteristics of a dispersion-

shifted single-mode optical fibre

and cable

1988

Characteristics of a cut-off shifted

single-mode optical fibre and cable

Characteristics of a non-zero

dispersion-shifted single-mode

optical fibre and cable

1996 Nov. 2009

Oct. 2012

B5

Dispersion unshifted fibre

Dispersion unshifted fibre, extended

band

Dispersion shifted fibre

Dispersion unshifted, Loss-minimize,

Cut-off shifted fibre

Non-zero dispersion shifted fibre

Wideband non-zero-dispersion shifted

fibre

B1.1

B1.3



7

IEC SC86A Fibre Cables Standards (60794)


60794-1-1

Generic General

SpecificationsTest methods

60794-1-2 60794-1-21 60794-1-22 60794-1-23

Cross ref table General Mechanical Environmental Cable elements Electrical

Sectional

Specifications

Family

Specifications60794-3-10 60794-3-20 60794-3-30 60794-3-40 60794-3-50 60794-3-60 60794-4-10 60794-4-20 60794-5-10 60794-5-20

Gas pipe Outdoor Outdoor

Cables OPGW ADSS microducts fibre units &

cables and cables microducts

Product and Detail

Specifications

Technical Reports

TR 62470 TR 62362 TR 62691 TR62690

Measurement Guide for

of COF between installation

cables and ducts

(NWP)Breakout

cable w ith

connectors

(NWP)

Guide for

Drop Cable

(NWP)

60794-2-22

60794-2

Indoor cables

60794-3

Outdoor cables

60794-4

Cables along overhead lines

60794-3-21

Premises

cabling

coastal appl.

Sewer

Cables

Aerial

cables

Cables: lakes

river crossings

60794-2-10

Simplex &

Duplex

cables

60794-2-20

Multi-fibre

cables

Cables w ith

plastic

60794-3-12

Premises

cabling

60794-3-11

Duct or

buried

cables

Duct, buried

or lashed

cables

60794-2-30

Ribbon

cables

60794-2-11

Premises

cabling

60794-2-21

Premises

cabling

60794-2-31

Premises

cabling

60794-2-41

Buffered

A4 fibres

cables with

A4 fibres

60794-1-2

60794-1-20

60794-2-51

Sim/Duplex

cables for

patchcords

60794-2-42

Sim/Duplex

fibres

60794-2-50

Sim/Duplex

cables for

patchcords

60794-2-40

60794-1-24

MICE

belongs to

ISO/IEC JTC1

SC25

Guide for

hydrogen

Drinking

water pipe

Microduct cabling (blowing)

60794-5

TR62690 TR62763

Guide for

MDU Cable


8FTTH Conference 2013, London, 2013-02-19

Standardization is NOT a goal in itself…

Standardization is supporting Trade & Commerce�� Essential, also for FTTH appl.

So, let’s look at the facts & figures behind all these fibre & cable types ……


9

Facts & Figures: Fibre Type Split Source CRU International August 2012

Current Single-Mode Fibre Types


G.652

A/B

11%

G.652

C/D

88%

G.655

&

G.656

1%

2012

G.652

A/B

7%

G.652

C/D

92%

G.655 &

G.656

1%

2017

Market (in km) split per fibre type; ultra-dominant G.652 family

Inside G.652, almost all the volume at G.652 C/D grade

G.657 volumes, heavily growing, not yet tracked separately


10

In 2012 demand: 240 Mfkm installed (+14% growth)

Key drivers for fibre consumption: FTTx and mobile backhaul

2 billions kilometers deployed since 90’s, 50’000 times the Earth perimeter!



Cabled fibre per application [million-km]

World Fibre Consumption

0

50

100

150

200

250

Others

Cable Operators

Local & Metro

Long distance

FTTx

Submarine

0

50

100

150

200

250

Other Metro

Mobile backhaul

Source CRU International


Internet bubble


11

Significant volume increase for G.657 bend-insensitive SM-fibre consumption worldwide

Driven by the boost of indoor deployments and lately outdoor roll-outs



Growth G657 BI-SMFFibre demand(in ’000s of km)

0

2.000

4.000

6.000

8.000

10.000

12.000

14.000

16.000

10 mm

7.5 mm

5 mm


~5% Total global SMF volume


12

�� Bends, indoor installation, higher density, smaller footprint… �� Fibre must offer improved tolerance to handling constraints

More compact connectivity

Corners, staples,…

Retractable modules

Constraints in FTTH Access & MDU


Riser Cable Basement Box

Termination Device

Distr. Cable

Floor Box

Riser Shaft

Access: High fibre count / compact cables (e.g. 720 fibres)


13

Future proof installation:Need for bend-insensitive SMF

PON Evolutions & Band Usage



14

Dec. 2006: G.657 edition #1Access: G.657.A: compliant with G.652.D

Building: G.657.B: not full compliance G.652.D

Low bending losses at low bend radii

Short distances

Nov. 2009: publication of edition #2Two extra sub-categories:

Access: G.657.A1 + G.657.A2

Building: G.657.B2 + G.657.B3

Oct. 2012: publication of edition #3Strong improvement G.657.B:

New Chrom.Disp + PMD specs

Deletion 6.3um MFD (spec as G.652.D)

All bands 1260 – 1625nm

G.657.B nearly same as G.652.D

System compatible with G.652.D�� More acceptable for operators


ITU-T Rec. G.657”Characteristics of a bending loss insensitive single mode optical fibre and cable for the access network”


15

A1, A2, B2, B3 sub-categories: maintaining A and B structure

Most bend resistant fibres:

G.657.A2 � Rmin = 7.5mm � G.652.D compliant

G.657.B3 � Rmin = 5mm � G.652.D compatible

Structure edition #3 (10/2012)

ITU-T Rec. G.657 / 2012

G.652G.657 A1

G.657 A2 / B2

G.657 B3



16

Large weight for civil works and installation in deployment costsversus passive material cost and active equipment cost

Any improvement in deployment and installation techniques is a dominating factor to reduce the Total Cost of Ownership (TCO) of an FTTH network

Examples FTTH Roll-out Cost Saving


CO active eq'ts

26%

Subs active

eq'ts

16%

Passive

Material

12%Deployment

46%

Source FTTH Business Guide (FTTH Council Europe)

Example


17

For P2P networks high fibre count cables are required with minimal outer cable diameter:

Minimum impact of crowded ducts (large cities) � E.g. 720 fibre count cables

� Recent standardization update: 200 µm coated fibres (G.657.A2 also microbend insensitve)

�� IEC SC86A: 60793-2-50 Ed4 (2012-12)

� Micro-module technique (Flextube) / Reduced thickness

OSP: Compact Access Cables (G.657.A2)


Fibre Core

‘Regular’ 250µm coating

Coating Secondary LayerCoating Primary Layer

Cladding

‘Compact’ 200µm coating

Same standardized glass dimensions (fibre core & cladding)

Reduced size protective coating (primary & secondary)

Smaller fibre size. Higher density.

Cross section

reduced by 70%


18

For P2P networks high fibre count cables are required with minimal outer diameter:

Minimum impact of crowded ducts (large cities) � E.g. 720 fibre count cables

� Recent standardization update: 200 µm coated fibres

� 720 fibre cable O.D.: from 21mm to ~15mm

Lower duct renting fees

Greener applications � Less raw material and civil works

G.657.A2 (IEC: B6_a2) support such compact cables

IEC 60794-3 (Outdoor cable) in revision to include micro-modules

OSP: Compact Access Cables (G.657.A2)

Inner duct

diameter



19

Outdoor cables with low friction coefficient fibre modules

Window-cuts made at multiple points along cable length � individual modules cut and retracted back to previous window-cut

Fibre modules pushed or blown into microducts to reach a termination or distribution point (typically in customer premises)

Direct buried cables- reference -

100

Rela

tive c

ost

co

mp

ari

so

n (

%)

80

60

40

20

0Direct buried micro-ducts

Retractable cables

Labor cost

Materials cost

Modeling of retractable solutionshows TCO reduction up to 10-20%

Retractable cables part of IEC TR 62762 Drop cable (u.d.)

OSP: Retractable Solutions


1 OPEN

4 PUSH/BLOW

2 CUT

3 PULL


Indoor cable equipped with bend-loss reduced G.657.B (IEC B6_b) fibres support low-loss building installations at the end of the Access Network� Necessary due to limited

optical link budgets

Indoor: Bend-Insensitive fibres (G.657.B)3mm stapledindoor cable w. G.657.B2 fibre:

• 89 staples

• 15 angles 90°

• 1550 nm

• Attenuation:max. 0,05 dB


21

Retractable riser cablesfrom distribution point to top floor, containing individual modules with fibre units or fibre bundles�� Example in France

Window and module-cutson a higher floor:� at lower targeted floor

modules can be retracted and rerouted (up to 20m away)

IEC TR 62763 “Guide to Multi-Dwelling Unit Fibre Optic Cable Networks “ being drafted

Drop cablesSubscriber #1

Subscriber #2

Subscriber #3

ISP #1 ISP #2 ISP #3 ISP #4

Multi-operator

branching area

Indoor: Retractable Solutions


MDU cables


22

Pre-connectorizedRiser Cables

Each micro-module(riser cable) dedicated to one subscriber

Each group of connectors dedicated to one operator

Fanout #1

Fanout #2LSZH tube

Indoor: Pre-Connectorised Solutions



“Drop Cable” vs “MDU Cable”�� Definition of a “Drop Cable”

Closes the gap between distribution cables (starting at the Network Access Point (NAP)) and the single user´s home, Multi Dwelling Units (MDUs), or other premises.

Aerial, duct or direct buried cables, as well as indoor / outdoor cables and cables to be installed on facades.

Ends either outside or insidethe building. So, indoor / outdoor cables maybe needed providing appropriate fire protection.

IEC TR 62762 draft in preparation

23FTTH Conference 2013, London, 2013-02-19

�� Definition of an “MDU Cable”

Provides connection from where the drop cable enters the building to the single user´s apartment.

Indoor cable

Does not include residential property cabling that may be present in the customer’s home.

IEC TR 62763 draft in preparation

Definitions may change as the IEC documents develop!


24

IEC TR 62762 draft Drop Cable

IEC TR 62763 draft MDU Cable

Splice loss G.652 / G.657 fibres

Uni-directional OTDR

MFD specs


Current Discussions in Standardization


25

…. Uni-directional OTDR testing


Discussions: splicing FTTH Fibres

G652 �� G657 G657 �� G652

MFD G652 > MFD G657

FTTH: often uni-directional OTDR cable plant commissioning

OTDR is not directly measuring loss, but instead back-scattered optical power, inversely proportional to MFD of fibre

Uni-directional OTDR traces may show “gainers” or “losers” when MFDs of connected fibres differ (e.g. G652 vs G657)

True splice loss is computed by averaging the power transition height acquired in both directions (cancelling “gainers / losers”)


26



Which splice spec to use for uni-directional OTDR?

It should be wider than that for official bi-directional OTDR

Let’s assume 0.45 dB

Let’s study the following 4 cases with different median MFD

Nominal MFD1310

& Tolerance

G.652 G.657 Delta nom.

MFD

CASE A 9.0

0.4 µm

8.8

0.4 µm

0.2 µm

CASE B 9.2

0.4 µm

8.8

0.4 µm

0.4 µm

CASE C 9.0

0.4 µm

8.6

0.4 µm

0.4 µm

CASE D 9.2

0.4 µm

8.6

0.4 µm

0.6 µm



27



WhichPulse width : 20 ns; 1550 nmLaunching from the G.652 to the G.657 fibers

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

-0.80 -0.70 -0.60 -0.50 -0.40 -0.30 -0.20 -0.10 0.00 0.10 0.20

Contribution to Raleygh Scattering mismatch (dB) to the unidirectional OTDR reading

Cumumated Distribution

CASE A CASE B CASE C CASE D

45%

~5%

0.2%

Assuming perfect splice:% spices of apparent

gain higher than -0.45dB when launching

for G652 to G.657

Lowest risk for rework in

Case A with smallest MFD

difference


G652: 9.2 ± 0.4 umG657: 8.6 ± 0.4 um

G652: 9.0 ± 0.4 umG657: 8.8 ± 0.4 um


28



WhichPulse width : 20 ns; 1550 nmLaunching from the G.657 to the G.652 fibers

Lowest risk for rework in

Case A with smallest MFD

difference

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

-0.20 -0.10 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80

Rayleigh Backward Scattering Mismatch (dB)

Cumumated Distribution

CASE A CASE B CASE C CASE D

45%

~5%

0.2%

Assuming perfect splice:% spices of apparent

loss higher than 0.45dB when launching

for G657 to G.652


G652: 9.2 ± 0.4 umG657: 8.6 ± 0.4 um

G652: 9.0 ± 0.4 umG657: 8.8 ± 0.4 um



Smallest chance on large uni-directional OTDR mismatch when MFD differences between fibres are minimized

Proposals for reducing current wide MFD range:

Current MFD G652/G657: median range: 8.6 – 9.5 µm / Tol. ±0.6 µm

New proposal: median range: 8.8 – 9.2 µm / Tol. ±0.4 µm


8.0 8.5 9.0 9.5 10.0 µm

Current MFD spec

Suggested MFD spec


For supporting FTTH applications Optical Fibre & Cable standards have been developed and are subject of constant revision following the latest trends:

ITU-T Recommendation G.657

IEC Standard 60793-2-50, category B6

IEC Standard series 60794-2 (Indoor) / 60794-3 (Outdoor)

�� In close harmonization between ITU-T and IEC

New documents are in development:

IEC TR 62762 draft Drop Cable

IEC TR 62763 draft MDU Cable

New issues need further discussion:

Uni-directional OTDR commissioning

MFD specifications G652 and G657 fibres

Conclusions


31

Thank you for your attention

Questions?

[email protected]


gerard kuyt

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