2020 © ADTRAN, Inc.

ADTRAN Investor Overview

November 17, 2020

Needham Virtual Security, Networking and Communications Conference

Safe Harbor StatementDuring the course of this meeting, ADTRAN representatives expect to make forward-looking statements, which reflect management’s best judgment, based on factors currently known. However, these statements involve risks and uncertainties, as detailed in our Annual Report on Form 10-K for the year ending on December 31, 2019, and on Form 10-Q for the quarter ending September 30, 2020. These risks and uncertainties could cause actual results to differ materially from those in the forward-looking statements, which may be made during this meeting.

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ADTRAN at a Glance

• Founded in 1985 • Publicly traded since 1994 (NASDAQ: ADTN)• Headquartered in Huntsville, Alabama• U.S. and European engineering, manufacturing,

and support• $530M Revenue (2019)• More than a million units shipped annually• Thousands of customers in over 60 countries

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We are a leading global provider of networking equipment, software and services.

O U R U N I Q U E A P P R O A C H ,

U N M A T C H E D D O M A I N E X P E R T I S E

A N D I N N O V A T I V E P L A T F O R M S ,

M A K E Y O U R N E T W O R K T H E W A Y I T S H O U L D B E .

OUR VISIONTo enable a fully connected world where the power

to communicate is available to everyone, everywhere.

B R I N G I N G T H E W O R L D T O G E T H E R

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Fiber Access & Fiber Extension

Connected Home &Business

Global Services & Support

OUR BUSINESS FOCUS.Your Network. The Way It Should Be.

Access solutions with highest capacity and

lowest latency

Control and insight into service delivery

experience

Cost-effectively and in a timely manner meet

broadband deployment guidelines

SOLUTIONS FOCUSAD T RAN P O RT FO LI O

Connected Home and BusinessBroadband Access

Fiber Access Systems Fiber Extension Solutions Connected Home Connected Business

Cloud-based E2E Service Insight and Optimization

Service Automation

Service Automation & Optimization

FINANCIAL REPORTINGADTRAN operates in two business segments:

(1) Network Solutions includes hardware and software products.

(2) Services & Support includes a portfolio of services that complement our products.

Three revenue categories span across these two segments:(1) Access & Aggregation is focused on solutions that are

used by service providers to connect their network infrastructure to subscribers.

(2) Subscriber Solutions & Experience is concentrated on subscriber solutions in the home and/or business.

(3) Traditional & Other Products encompasses prior-generation technologies, products and services.

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DEMAND DRIVERSCloud solution providers are driving the demand for

bandwidth intensive applications with simple and easy, user-driven interfaces.

ConnectedDevices

StreamingVideo

CloudGaming

B R I N G I N G T H E W O R L D T O G E T H E R

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DEMAND CATALYSTCOVID-19 has created unprecedented

demand to close the digital divide.

Connect with Friends/Family

Work FromHome

Telemedicine

B R I N G I N G T H E W O R L D T O G E T H E R

COVID-19

On-lineLearning

20 - 40% increasebroadband traffic

Entertainment

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Govt Regulations and Policies

5G & CableBuildout

Govt Subsidies, VC Investment

INVESTMENT DRIVERSEvolution of government funding programs, regulatory broadband policies

investment community guide operators’ network investment strategies..

B R I N G I N G T H E W O R L D T O G E T H E R

Gig

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Funding TTMObligations

Trade Barriers

Network SecurityConcerns

INVESTMENT CATALYSTProviding a technically advanced alternative to incumbent suppliers as national operators

look to limit capital expenditure and supply chain risk.

B R I N G I N G T H E W O R L D T O G E T H E R

Supply ChainIntegrity

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Reduce OpEx

Increase ARPU

Retain / Expand Market Share

OPERATOR IMPERATIVESCommunications solution providers are investing in their

networks to promote increased subscriber ARPU, retention and acquisition while streamlining their operations.

B R I N G I N G T H E W O R L D T O G E T H E R

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Reduce OpEx

Increase ARPU

Retain / Expand Market Share

MARKET DYNAMICSB R I N G I N G T H E W O R L D T O G E T H E R

ADTRAN OPPORTUNITYMonetizing the connected home and business while expanding network capabilities

and modernizing access architectures.

Network Evolution& Service Velocity

Connected Home& Business

Broadband Capacity & Coverage

ConnectedDevices

StreamingVideo

CloudGaming

Regulation, Policies

5G & CableBuildout

Govt Subsidies, VC Investment

DEMAND INVESTMENT IMPERATIVES

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THE OPPORTUNITYMonetizing the connected home and business while expanding network capabilities

and modernizing access architectures.

Network Evolution& Service Velocity

2021 – 2025 5yr SAM

Connected Home& Business

2021 – 2025 5yr SAM

Broadband Access

2021 – 2025 5yr SAM

B R I N G I N G T H E W O R L D T O G E T H E R

$32B $18B $14B5 % C A G R3 % C A G R 1 % C A G R

Source: IHS/Dell’OroSource: Dell’Oro/GlobalData Source: TBR

B R I N G I N G T H E W O R L D T O G E T H E R

THE NETWORK

Fiber Access

Fiber Extension

Enterprise

Rural/Remote

60 GHz FWA

Gfast

Mobile

Multi-Dwelling

Single Family

GPONXGS-PON

End to End Network Control, Visibility, Automation & Optimization

LTE-based FWA

Open and Disaggregated

Platforms

XGS-PON

Integrated, Optimized Platforms

Fiber Access

ConnectedHome

Business Networking

Cloud Services and Network

Management

N x 100GE

N x 100GE

GPON

GPONXGS-PON

Aggregation andTransport

Aggregation andTransport

Outside Plant (OSP)

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B r o a d b a n d A c c e s s I n n o v a t i o n

FIBER ACCESS & FIBER EXTENSION

Your Network. The Way It Should Be.

Broadband Capacity & Coverage

Retain / Expand Market Share

Broadband Access Innovation

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Integrated, Optimized

Open, Disaggregated

Remote, Distributed

Regional, Municipal High Scale, Urban Rural, Cable MSO

MAXIMIZING THE MARKETProviding distinct and differentiated value for

each fiber access customer segment.

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CONNECTED HOME &SUBSCRIBER CLOUD

Your Network. The Way It Should Be.

Subscriber Experience

IncreaseARPU

Connected Home& Business

S U B S C R I B E R E X P E R I E N C E

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RESIDENTIAL & ENTERPRISE CONNECTIVITY

Wi-Fi GatewaysMultiple WAN options, Mesh Wi-Fi 6

GPON & XGS-PON ONTsIndoor, outdoor, pluggable

Enterprise WAN ConnectivityCE NIDs, Routers, IPBGs, SD-WAN

Enterprise LAN ConnectivityCloud-managed switches & access points

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Reduce OpEx

GLOBAL SERVICES& SUPPORT

Your Network. The Way It Should Be.

S E R V I C E D E L I V E R Y E V O L U T I O N

Network Migration& Service Velocity

Service Delivery Evolution

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ADTRANGlobal

Services

Hardware-centricOne-time ProjectsCopper-basedClosed, ProprietaryIncumbent Providers

Software-centricReoccurring ServicesFiber-basedOpen, Multi-vendorAlternative Providers

SERVICE DELIVERY EVOLUTION

Acknowledgment: The innovator's dilemma 1997

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Network audit and consultation, solution

integration, and resident engineering

Design, deployment & integration

servicesCopper to Fiber,

Fixed Wireless

Hardware and software support, spares and repair services. Priority

support and training

ADTRAN GLOBAL SERVICES

Implementation Maintenance Professional Managed Cloud

Subscriber, network& business cloud

services

Security, capacity monitoring,

inventory and NOC services

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B R I N G I N G T H E W O R L D T O G E T H E R

CUSTOMER DIVERSITY & OPERATOR SCALE

Increasing customer diversity inclusive of large operator scale to achieve more linear financial results and sustainable growth.

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REGIONAL, MUNICIPAL PROVIDERSMust launch new services, markets rapidly • Turnkey design, integration, activation • Pre-tested, pre-integrated solution

Have limited technical resources• Best in Class mesh Wi-Fi 6• In-home visibility and network ops SW tools

Desire long term suppler relationship• Right-sized, regionally market focused supplier• Complete gigabit broadband portfolio

spanning access, home and business

OU R U NI QU E AP P R OAC H , U NMAT C H E D D OMAI N E X P E R I E NC E , I NNOV AT I V E P L A T F O R M S

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Total Access 500010G Fiber Access Platform

Combo PON

LTE-based Fixed Wireless

Rural

SFU Wi-FI6 Mesh

GPON

SMB

Switches, Routers

Business Wi-Fi

End to end network visibility, analytics and optimization

ADTRAN Mosaic Software Suite

U.S. RSP MARKET MOMENTUM

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GLOBAL NETWORK OPERATORS

Plan broadband network modernization• Only deployable SD-Access reference

architectures• Complete gigabit broadband portfolio

(Urban, Rural, MDU)

Require supply chain diversity • Tier I access experience; next gen category leader• World-class supply chain capacity, continuity

Top 20 garner 60% of global wallet share• Provide sustainable long term revenue streams

OU R U NI QU E AP P R OAC H , U NMAT C HE D D OMAI N E X P E R I E NC E , I NNOV AT I V E P LA T F OR MS

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Market Capture and Customer

Loyalty

OperationalSimplification

Supply Chain Diversity and

Security

GLOBAL TIER 1 MARKET MOMENTUM

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NetworkEvolution

Subscriber Experience

Broadband AccessInnovation

B R I N G I N G T H E W O R L D T O G E T H E R

OUR STRATEGYOur unique approach, unmatched domain expertise

and innovative platforms, make your network they way they should be.

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2020 – A Pivotal Year for BroadbandI N D US T RY L AN D S CAPE

Technology Transition

Architectural Changes

Broadband Policies

New Market Entrants

Vendor Disruption

Ramp of 10G PON, Gfast,

fixed wireless, and mesh

Wi-Fi 6

European Gigabit society,

EECC regulations

favoring disruptors,

RDOF/CAF, …

Influence of SDN, NFV,

disaggregation and open source on

target architectures

Low capital cost and

regulation favoring

munis, co-ops and

alternative operators

Vendor concerns,

vendor consolidation

and supply chain

diversification

Pandemic

Leap forward in bandwidth

utilization, especially in

the upstream; work from

home is the new norm

Even without the pandemic, 2020 was set up to be a generationally significant year in broadband access, setting the stage for the future.

B R I N G I N G T H E W O R L D T O G E T H E R

Your Network.The Way It Should Be.

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