characterizing opex in next generation fiber-to-the...

Materials Systems Laboratory

Characterizing OpEx in Next Generation Fiber-to-the-Home Access Networks:

Thomas Rand-NashDr. Richard RothProf. Rajeev Ram

Prof. Randolph Kirchain


Optical Broadband Working GroupI. Within Broadband Working Group in the

Communications Futures Program

II. OBBWG MIT Research ParticipantsMaterials Systems Laboratory (MSL)Center for Integrated Photonics (CIPS)

III. Corporate Working Group Members

IV. Other Participating Companies


Optical Broadband Working Group Goals

I. Understand how the technical status of optical components influences future FTTx architectures

II. Investigation of where optical components are headed including timing and cost issues

III. How technology and cost development path will influence network deployment strategies


Fiber to the Home: Proposed Network Solutions

Metro Edge

Optical Access Network

WDM-PON

QuickTime™ and a decompressor

are needed to see this picture.

QuickTime™ and a decompressor

are needed to see this picture.

GPON

LR -PON

M etro C o re

Central Office SplitterCentral Office

AWG/Splitter

Central OfficeAmplifier

Splitter

Materials Systems Laboratory5

Increasing Data Services Requirements

• Continued Increasing Data Bandwidth Demand•Demand for Video

• DSL Unlikely to Meet Longer Term Needs

Competition

Regulatory

• Entertainment Video

• Changing Regulatory Environment

Cost Improvements• Reduced Costs (Actives & Passives)• Reduced Maintenance Costs

FTTx Opportunities


Modeling Activities


Modeling Activity Overview

DemandDemographics

TechnologicalConstraints

OperatingContext

Central OfficeSiting

SplitterSiting

Fiber PlantSiting

Network ModelInputs

Network DesignModel

NetworkDesign

ComponentCosts

LaborCosts

Resource Costs

NetworkConstraints

Network Cost Models

NetworkCapEx

NetworkOpEx


Modeling Advantages

I. Ability to capture impacts of technological changeII. No comprehensive OpEx models exist

Only one paper published on topicWant to predict network operational characteristics

III. Enables a large solution spaceNot tied to legacyCan model next-gen components


Network Design Model

Each red dot represents:

-Number of locations passed

-Total data


Network Design Model


Model Validation


Network Design Model Validation:

I. Characterize key input parameters/constraints:Re-create coverage region demographics:

• Populations• Data demands• Geographic coverage region

Incorporate network architecture parameters:• Splitter strategies• Multiplexing strategy• Data transfer rates

II. Compare outputs required to satisfy constraints:• Total fiber plant route lengths• Splitter sites/number


Network Design Model: ValidationScenario (1) BT (1) MIT (2) Corning (2) MIT

Homes Passed 7353 7228 71331 71176

Splitter Strategy Non-Cascaded1x32

Cascaded1x4 1x8

Data Rate (Gbps) 2.5 2.5

Reach (km) 12 20

Central Offices 1 3

Route Length (km) 758 717 10357 10658

Stage 1 Splitters 263 294 2634 2607

Stage 2 Splitters N/A N/A 10658 10283

Model Inputs

Model Outputs


Analysis


Network Cost ModelsI. CapEx model: Maps component, labor, &

resource costs to network design II. OpEx model: Maps component reliability, &

operational labor/resource costs to network design

“Bottom-up” approach utilizes industry component failure modes, mode rates, costs

• FIT data• Reliability modeling

“Top-down” data provides observed component failure modes, mode rates, rents, energy etc.

• Carrier field data• Municipality field data


OpEx Analysis Involves Multiple Parameters

Intrinsic Failure Modes

Failure Mode FIT Rate Data

Material Repair/Replace Costs

Extrinsic Failure Modes

Observed FIT Rate Data

Man-hours to Repair/Replace

Resource Costs

Power Costs

Rents

Administrative Labor

Model Input Parameters:Network Components:ONT

Fiber

Splitters

OLT

Connectors

Splices

Non-OLT Central Office

Industry Data (Bottom-up)Field Data (Top-Down)


Scenarios ModeledScenario (3)Base Case (4)Long Range (5)High Split

Homes Passed 61711

Penetration Modeled 30%

Data Rate (Gbps) 2.5

Power Margin (dB) 3

Splitter Loss (dB) 3.5 per log(N)

Fiber Loss (dB) 0.3 per km

Splitter Strategy 1x4 1x8 1x4 1x8 1x4 1x32Reach (km) 5 20 20

Central Offices 4 1 1

ONT Rx Type: PIN APD APD

Rx Sensitivity (dBm) -25 -31 -31

OLT Tx Power (dBm) -3 -3 +3


$0

$200

$400

$600

$800

$1,000

$1,200

$1,400

(3) (4) (5)

Cap

Ex p

er

Su

bsc

rib

er

COFiberHardwa

(3) 5km (4) 20km (5) 20km1x4,1x8 1x4,1x8 1x4,1x32

BC LR HS

CapEx

CapEx By Network Component

22% Savings4.5% Savings

Total$1282

Total$1001

Total$1225


$0

$10

$20

$30

$40

$50

$60

$70

$80

$90

(3) (4) (5)

An

nu

al O

pEx p

er

Su

bsc

rib

er

COFiber Hardware

OpEx By Network Component

(3) 5km (4) 20km (5) 20km1x4,1x8 1x4,1x8 1x4,1x32

OpEx

52% Savings 62% Savings

BC LR HS

Total$77.59 Total

$29.70

Total$37.38


Annual OpEx Savings per Sub vs. Base Case

$0.73$0.09

$39.39

62% Savings($47.89)

52% Savings($40.21)

High Split Count vs. Base CaseLonger Reach vs. Base Case

$3.90$0.40

$43.59


OpEx By Network Cost Driver

$29.5

$14.3 $11.5

$36.3

$9.07

$10.7

$11.0

$9.64

$5.07

$0

$10

$20

$30

$40

$50

$60

$70

$80

$90

3 4 5

An

nu

al

Op

Ex p

er

Su

bsc

rib

er

MaterialsPower/RenLabor

Total$29.70

Total$37.38

Total$77.59

(3) 5km (4) 20km (5) 20km1x4,1x8 1x4,1x8 1x4,1x32


Future Work: Short Term

I. Model additional link budgetsII. Continue OpEx data collection

Component reliabilitiesReal-World network failure statistics

III. Move to incorporate backhaul costsIV. Develop optoelectronic reliability model

• Predict/characterize next-gen component failure modes• Predict/characterize failure rates• Characterize network failure cost effects


Thank You

Questions?

characterizing opex in next generation fiber-to-the...

Documents