ADTRAN, INC. EQUITY DEFERRALPROGRAM FOR EMPLOYEES Restated effective October 1, 2011 CONTENTS

Exhibit 10.3 (p)

ADTRAN, INC. EQUITY DEFERRAL PROGRAM FOR EMPLOYEES

Restated effective October 1, 2011

CONTENTS

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ARTICLE 1

Preamble

ADTRAN, Inc. hereby restates the portion of the ADTRAN, Inc. Equity Deferral Program for Employees and Directors (“EDP”) that covers Employees. The EDP was originally adopted, effective June 1, 2010, as one of several programs offered under the ADTRAN, Inc. Deferred Compensation Plan. As part of this restatement, the EDP is being spun-off from the ADTRAN, Inc. Deferred Compensation Plan and split into two separate plans for Employees and Directors. This Plan shall be named the ADTRAN, Inc. Equity Deferral Program for Employees. This Plan spinoff shall be effective October 1, 2011.

This Plan is intended to be unfunded, maintained primarily for the purpose of providing deferred compensation for a select group of management or highly compensated employees of the employees of the Employer in compliance with all applicable laws (including Code section 409A), and operated and interpreted in accordance with these intentions.

ARTICLE 2

Definitions

Whenever the following capitalized terms are used in this Plan, they shall have the meaning specified below unless the context clearly indicates to the contrary.

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provided that this Plan is not aggregated with a plan subject to Code section 409A in which the Director Participant participates as an employee of the Employer or a Related Employer or in which the Employee Participant participates as a director (or a similar position with respect to a non-corporate entity) of the Employer or a Related Employer, as applicable, pursuant to Treasury Regulations section 1.409A-1(c)(2)(ii).

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ARTICLE 3

Eligibility

3.1 Date of Participation. An Employee will become a Participant on the date the Employer designates in writing (which writing is hereby incorporated herein) that such Participant is eligible to participate in the Plan. Such designation will include the effective date of such participation.

All Participants who timely submit properly-completed election forms may defer Employer Stock and/or Performance Shares as described in this Plan. The Administrator shall establish the enrollment procedure, which may include electronic documents and online submission.

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ARTICLE 4

Participant Deferrals

4.1 Deferrals. To the extent allowed by the Administrator, each Participant may elect pursuant to this Plan to defer into his or her Account up to 100% of the Employer Stock and/or Performance Shares that would otherwise be payable to him or her under one or more equity incentive programs sponsored by ADTRAN, Inc., after any tax or other required deductions.

In no event may the Participant, directly or indirectly, elect such a cancellation. A cancellation pursuant to this subsection (b) shall apply only to Employer Stock and Performance Shares not yet earned.

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4.2 Irrevocability of Deferral Elections. Except as provided in Section 4.1(b), a Participant’s election to defer Employer Stock and/or Performance Shares is irrevocable for the Plan Year to which it relates.

4.3 Distribution Elections. Deferral Contributions made with respect to a Plan Year, if any, and associated investment earnings or losses, shall be distributed at the time and in the form set forth in Article 8 of this Plan.

ARTICLE 5

Participant Accounts

5.1 Accounts. The Administrator may establish and maintain for each Participant an Account and one or more separate subaccounts, as determined by the Administrator (collectively, “Account”), which shall be credited with the Participant’s Deferral Contributions.

ARTICLE 6

Investment of Accounts

6.1 Crediting of Deferred Compensation. Each Participant’s Account shall be credited with shares of ADTRAN, Inc. common stock equal to the number of shares of Employer Stock and Performance Shares that such Participant has elected to defer under Article 4 and which would otherwise have been paid to the Participant.

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6.3 No Actual Investment. Notwithstanding any other provision to the contrary, the investments described in this Plan are to be used for measurement purposes only, and the crediting or debiting of amounts to a Participant’s Account shall not be considered or construed in any manner as an actual investment of his or her Account in any investment fund or ADTRAN, Inc. common stock. In the event that the Employer, in its own discretion, decides to invest funds in any one or more investments or in ADTRAN, Inc. common stock, no Participant shall have any rights in or to such investments themselves. Without limiting the foregoing, a Participant’s Account shall at all times be a bookkeeping entry only and shall not represent any investment made on the Participant’s behalf by the Employer (even though the funds credited to a Participant’s Account are held in the Trust as described in Section 10.6); the Participant shall at all times remain an unsecured creditor of the Employer.

ARTICLE 7

Right to Benefits

7.1 Vesting. Each Participant’s interest in his or her Account attributable to his or her Deferral Contributions shall be 100% vested and non-forfeitable at all times.

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7.2 Death. A Participant may designate a Beneficiary or Beneficiaries to receive his or her Account upon the Participant’s death, or change any prior designation of Beneficiary or Beneficiaries, by giving notice to the Administrator on a form designated by the Administrator. If more than one person is designated as the Beneficiary, their respective interests shall be as indicated on the designation form.

Immediately following the death of the Participant, a copy of the death certificate or other sufficient documentation must be filed with and approved by the Administrator. If upon the death of the Participant there is, in the opinion of the Administrator, no designated Beneficiary for part or all of the Participant’s Account, such amount will be paid to his surviving spouse or, if none, to his estate (such spouse or estate shall be deemed to be the Beneficiary for purposes of the Plan). If a Beneficiary dies after benefits to such Beneficiary have commenced, but before they have been completed, and, in the opinion of the Administrator, no person has been designated to receive such remaining benefits, then such benefits shall be paid to the deceased Beneficiary’s estate.

ARTICLE 8

Distribution of Accounts

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8.2 Notice to Trustee. The Administrator will provide direction to the Trustee, as provided in the Trust agreement, whenever any Participant or Beneficiary is entitled to receive benefits under the Plan. The Administrator’s notice shall indicate the form, amount and frequency of benefits that such Participant or Beneficiary shall receive.

8.3 Unforeseeable Emergency Withdrawals. Notwithstanding anything herein to the contrary, a Participant may apply to the Administrator to withdraw some or all of his Account if such withdrawal is made on account of an Unforeseeable Emergency as determined by the Administrator in accordance with the requirements of and subject to the limitations provided in Treasury Regulations section 1.409A-3(i)(3).

8.4 Applicable Taxes. The Employer may withhold applicable taxes from the Participant’s cash or in-kind compensation, in a manner and at times determined by the Employer. If necessary, the Administrator may reduce the Participant’s Account as applicable, in order to comply with this Section. While this Plan is intended to provide tax deferral for Participants, this Plan is not a guarantee that the intended tax deferral will be achieved. Participants are solely responsible and liable for the satisfaction of all taxes and penalties that may arise in connection with this Plan (including any taxes arising under Code section 409A). Neither the Employer nor its affiliates nor any of their directors, officers or employees shall have any obligation to indemnify or otherwise hold any Participant harmless from any such taxes.

ARTICLE 9

Amendment and Termination.

9.1 Amendment by Employer. ADTRAN, Inc. reserves the authority to amend the Plan in its discretion. Any such amendment notwithstanding, no Participant’s Account shall be reduced by such amendment below the amount to which the Participant would have been entitled if he had voluntarily left the service of the Employer immediately prior to the date of the change.

9.2 Termination. ADTRAN, Inc. has no obligation or liability whatsoever to maintain the Plan for any length of time and may terminate the Plan at any time without any liability hereunder for any such discontinuance or termination. Such termination shall comply with Treasury Regulations section 1.409A-3(j)(ix) and other applicable guidance.

ARTICLE 10

Miscellaneous Provisions

10.1 Limitation of Rights. Neither the establishment of the Plan and the Trust, nor any amendment thereof, nor the creation of any fund or account, nor the payment of any benefits, will be construed as giving to any Participant or other person any legal or equitable right against the Employer, Administrator or Trustee, except as provided herein; in no event will the terms of employment or service of any individual be modified or in any way affected hereby. The doctrine of substantial performance shall have no application to Participants or any other persons entitled to payments under the Plan.

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10.2 Nonalienability of Benefits. The benefits provided hereunder will not be subject to alienation, assignment, garnishment, attachment, execution or levy of any kind, either voluntarily or involuntarily, and any attempt to cause such benefits to be so subjected will not be recognized, except to such extent as may be required by law and as provided pursuant to a domestic relations order (defined in Code section 414(p)(1)(B)), as determined by the Administrator. Pursuant to a domestic relations order, payments may be accelerated to a time sooner, and pursuant to a schedule more rapid, than the time and schedule applicable in the absence of the domestic relations order, provided that such payment pursuant to such order is not made to the Participant and provided further that this provision shall not be construed to provide the Participant discretion regarding whether such payment time or schedule will be accelerated.

10.3 Facility of Payment. In the event the Administrator determines, on the basis of medical reports or other evidence satisfactory to the Administrator, that the recipient of any benefit payments under the Plan is incapable of handling his affairs by reason of minority, illness, infirmity or other incapacity, the Administrator may disburse such payments, or direct the Trustee to disburse such payments, as applicable, to a person or institution designated by a court which has jurisdiction over such recipient or a person or institution otherwise having the legal authority under state law for the care and control of such recipient. The receipt by such person or institution of any such payments shall be complete acquittance therefor, and any such payment to the extent thereof, shall discharge the liability of the Trust for the payment of benefits hereunder to such recipient.

10.4 Plan Records. The Administrator shall maintain the records of the Plan on a calendar-year basis.

10.5 USERRA. Notwithstanding anything herein to the contrary, the Administrator shall permit any Participant election and make any payments hereunder required by the Uniformed Services Employment and Reemployment Rights Act of 1994, as amended, 38 USC 4301-4334.

10.6 Funding. The Employer may create one of more Trust(s)with one or more Trustee(s). Although the principal of each Trust and any earnings thereon shall be held separate and apart from other funds of Employer and shall be used exclusively for the uses and purposes of Participants and there Beneficiaries as set forth therein, neither the Participants nor their Beneficiaries shall have any preferred claim on, or any beneficial ownership in, any assets of the Trust prior to the time such assets are paid to the Participants or their Beneficiaries as benefits and all rights created under this Plan shall be unsecured contractual rights of Participants and their Beneficiaries against the Employer. Any assets held in a Trust will be subject to the claims of the Employer’s general creditors under federal and state law in the event of insolvency or bankruptcy as defined in the Trust.

10.7 Governing Law. All disputes relating to or arising from this Plan shall be governed by ERISA and to the extent applicable the internal substantive laws (and not the laws of conflicts of laws) of the State of Alabama, to the extent not preempted by the United States federal law. If any provision of this Plan is held by a court of competent jurisdiction to be invalid and unenforceable, the remaining provisions shall continue to be fully effective.

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ARTICLE 11

Plan Administration

11.1 Powers and Responsibilities of the Administrator. The Administrator has the full power and the full responsibility to administer the Plan in all of its details, subject, however, to the applicable requirements of ERISA. The Administrator’s powers and responsibilities include, but are not limited to, the following:

All decisions of the Administrator with respect to the operation, interpretation, or administration of this Plan or a Participant’s Account, all actions taken by the Administrator, and all determinations made by the Administrator shall be final and binding upon all participants, the Employer, and any interested persons.

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The Plan Administrator shall provide the claimant with written notification of the Plan’s benefit determination on review. In the case of an adverse benefit determination, the notification shall set forth, in a manner calculated to be understood by the claimant — the specific reason or reasons for the adverse determinations, reference to the specific Plan provisions on which the benefit determination is based, a statement that the claimant is entitled to receive, upon the claimant’s request and free of charge, reasonable access to, and copies of, all documents, records, and other information relevant to the claim for benefits.

11.3 Indemnification by the Employer: Liability Insurance. The Employer shall pay or reimburse any of the Employer’s officers, directors, administrators, subcommittee members, delegates, or employees who are fiduciaries with respect to the Plan for all expenses incurred by such persons with respect to, and shall indemnify and hold them harmless from, all claims, liability and costs (including reasonable attorneys’ fees) arising out of the good faith performance of their duties under this Plan. The Employer may obtain and provide for any such person, at the Employer’s expense, liability insurance against liabilities imposed on such person by law.

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IN WITNESS WHEREOF ADTRAN, Inc. has caused this restatement of the Plan executed this 11^th day of October, 2011.

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APPENDIX A

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