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                                                                     EXHIBIT 4.3


                             DIGI INTERNATIONAL INC.
                          EMPLOYEE STOCK PURCHASE PLAN


         1. PURPOSE AND SCOPE OF PLAN. The purpose of this Digi International
Inc. Employee Stock Purchase Plan (the "Plan") is to provide the employees of
Digi International Inc. (the "Company") with an opportunity to acquire a
proprietary interest in the Company through the purchase of its Common Stock
and, thus, to develop a stronger incentive to work for the continued success of
the Company. The Plan is intended to be an "employee stock purchase plan" within
the meaning of Section 423(b) of the Internal Revenue Code of 1986, as amended,
and shall be interpreted and administered in a manner consistent with such
intent.

         2. DEFINITIONS.

         2.1. The terms defined in this section are used (and capitalized)
elsewhere in this Plan:

                  (a) "Affiliate" means any corporation that is a "parent
         corporation" or "subsidiary corporation" of the Company, as defined in
         Sections 424(e) and 424(f) of the Code or any successor provision, and
         whose participation in the Plan has been approved by the Board of
         Directors.

                  (b) "Board Of Directors" means the Board of Directors of the
         Company.

                  (c) "Code" means the Internal Revenue Code of 1986, as amended
         from time to time.

                  (d) "Committee" means three or more Disinterested Persons
         designated by the Board of Directors to administer the Plan under
         Section 13.

                  (e) "Common Stock" means the common stock, par value $.01 per
         share (as such par value may be adjusted from time to time), of the
         Company.

                  (f) "Company" means Digi International Inc.

                  (g) "Compensation" means the gross cash compensation
         (including wage, salary, commission, bonus, and overtime earnings) paid
         by the Company or any Affiliate to a Participant in accordance with the
         terms of employment.

                  (h) "Disinterested Persons" means a member of the Board of
         Directors who is considered a disinterested person within the meaning
         of Exchange Act Rule 16b-3 or any successor definition.





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                  (i) "Eligible Employee" means any employee of the Company or
         an Affiliate who has been employed for at least 90 days and whose
         customary employment is at least 20 hours per week; provided, however,
         that "Eligible Employee" shall not include any person who would be
         deemed for purposes of Section 423(b)(3) of the Code, to own stock
         possessing 5% or more of the total combined voting power or value of
         all classes of stock of the Company.

                  (j) "Exchange Act" means the Securities Exchange Act of 1934,
         as amended from time to time.

                  (k) "Fair Market Value" of a share of Common Stock as of any
         date means, if the Company's Common Stock is listed on a national
         securities exchange or traded in the national market system, the mean
         between the high and low sale prices for such Common Stock on such
         exchange or market on said date, or, if no sale has been made on such
         exchange or market on said date, on A-1 the last preceding day on which
         any sale shall have been made. If such determination of Fair Market
         Value is not consistent with the then current regulations of the
         Secretary of the Treasury applicable to plans intended to qualify as an
         "employee stock purchase plan" within the meaning of Section 423(b) of
         the Code, however, Fair Market Value shall be determined in accordance
         with such regulations. The determination of Fair Market Value shall be
         subject to adjustment as provided in Section 14.

                  (l) "Participant" means an Eligible Employee who has elected
         to participate in the Plan in the manner set forth in Section 4.

                  (m) "Plan" means this Digi International Inc. Employee Stock
         Purchase Plan, as amended from time to time.

                  (n) "Purchase Period" means each quarter of the Company's
         fiscal year. The first Purchase Period will be the quarter that starts
         April 1, 1996 and ends June 30, 1996.

                  (o) "Recordkeeping Account" means the account maintained in
         the books and records of the Company recording the amount withheld from
         each Participant through payroll deductions made under the Plan.

         3. SCOPE OF THE PLAN. Shares of Common Stock may be sold by the Company
to Eligible Employees commencing April 1, 1996, as hereinafter provided, but not
more than 1,250,000 shares of Common Stock (subject to adjustment as provided in
Section 14) shall be sold to Eligible Employees pursuant to this Plan. All sales
of Common Stock pursuant to this Plan shall be subject to the same terms,
conditions, rights and privileges. The shares of Common Stock delivered by the
Company pursuant to this Plan may be acquired shares having the status of any
combination of authorized but unissued shares, newly issued shares, or treasury
shares.

         4. ELIGIBILITY AND PARTICIPATION. To be eligible to participate in the
Plan for a given Purchase Period, an employee must be an Eligible Employee on
the first day of such





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Purchase Period. An Eligible Employee may elect to participate in the Plan by
filing an enrollment form with the Company before the first day of such Purchase
Period that authorizes regular payroll deductions from Compensation beginning
with the first payday in such Purchase Period and continuing until the Eligible
Employee withdraws from the Plan, modifies his or her authorization, or ceases
to be an Eligible Employee, as hereinafter provided.

         5. AMOUNT OF COMMON STOCK EACH ELIGIBLE EMPLOYEE MAY PURCHASE.

         5.1. Subject to the provisions of the Plan, each Eligible Employee
shall be offered the right to purchase on the last day of the Purchase Period
the number of shares of Common Stock (including fractional shares) that can be
purchased at the price specified in Section 5.2 with the entire credit balance
in the Participant's Recordkeeping Account; provided, however, that the Fair
Market Value (determined on the first day of any Purchase Period) of shares of
Common Stock that may be purchased by a Participant during such Purchase Period
shall not exceed the excess, if any, of (i) $25,000 over (ii) the Fair Market
Value (determined on the first day of the relevant Purchase Period) of shares of
Common Stock previously acquired by the Participant in any prior Purchase Period
during such calendar year. Notwithstanding the foregoing, no Eligible Employee
shall be granted an option to acquire shares of Common Stock under this Plan
which permits the Eligible Employee's rights to purchase shares of Common Stock
under this Plan and all employee stock purchase plans of the Company and the
Affiliates to accrue at a rate which exceeds $25,000 of Fair A-2 Market Value
(determined at the time such option is granted) for each calendar year in which
such option is outstanding at any time. If the purchases by all Participants
would otherwise cause the aggregate number of shares of Common Stock to be sold
under the Plan to exceed the number specified in Section 3, however, each
Participant shall be allocated at a ratable portion of the maximum number of
shares of Common Stock which may be sold.

         5.2. The purchase price of each share of Common Stock sold pursuant to
this Plan will be the lesser of (a) or (b) below: (a) 85% of the Fair Market
Value of such share on the first day of the Purchase Period. (b) 85% of the Fair
Market Value of such share on the last day of the Purchase Period.

         6. METHOD OF PARTICIPATION.

         6.1. The Company shall give notice to each Eligible Employee of the
opportunity to purchase shares of Common Stock pursuant to this Plan and the
terms and conditions for such offering. Such notice is subject to revision by
the Company at any time prior to the date of purchase of such shares. The
Company contemplates that for tax purposes the first day of a Purchase Period
will be the date of the offering of such shares.

         6.2. Each Eligible Employee who desires to participate in the Plan for
a Purchase Period shall signify his or her election to do so by signing an
election form developed by the Committee. An Eligible Employee may elect to have
any whole percent of Compensation





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withheld, but not exceeding ten percent (10%) per pay period. An election to
participate in the Plan and to authorize payroll deductions as described herein
must be made before the first day of the Purchase Period to which it relates and
shall remain in effect unless and until such Participant withdraws from this
Plan, modifies his or her authorization, or terminates his or her employment
with the Company, as hereinafter provided.

         6.3. Any Eligible Employee who does not make a timely election as
provided in Section 6.2, shall be deemed to have elected not to participate in
the Plan. Such election shall be irrevocable for such Purchase Period.

         7. RECORDKEEPING ACCOUNT.

         7.1. The Company shall maintain a Recordkeeping Account for each
Participant. Payroll deductions pursuant to Section 6 will be credited to such
Recordkeeping Accounts on each payday.

         7.2. No interest will be credited to a Participant's Recordkeeping
Account.

         7.3. The Recordkeeping Account is established solely for accounting
purposes, and all amounts credited to the Recordkeeping Account will remain part
of the general assets of the Company.

         7.4. A Participant may not make any separate cash payment into the
Recordkeeping Account.

         8. RIGHT TO ADJUST PARTICIPATION OR TO WITHDRAW.

         8.1. A Participant may, at any time during a Purchase Period, direct
the Company to make no further deductions from his or her Compensation or to
adjust the amount of such deductions. Upon either of such actions, future
payroll deductions with respect to such Participant shall cease or be adjusted
in accordance with the Participant's direction. A-3

         8.2. Any Participant who stops payroll deductions may not thereafter
resume payroll deductions during such Purchase Period.

         8.3. At any time before the end of a Purchase Period, any Participant
may also withdraw from the Plan. In such event, all future payroll deductions
shall cease and the entire credit balance in the Participant's Recordkeeping
Account will be paid to the Participant, without interest, in cash within 15
days. A Participant who withdraws from the Plan will not be eligible to reenter
the Plan until the next succeeding Purchase Period.

         8.4. Notification of a Participant's election to adjust or terminate
deductions, or to withdraw from the Plan, shall be made by the filing of an
appropriate notice to such effect with the Company.





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         9. TERMINATION OF EMPLOYMENT. If the employment of a Participant is
terminated for any reason, including death, disability, or retirement, the
entire balance in the Participant's Recordkeeping Account will be applied to the
purchase of shares as provided in Section 10.1 as of the last day of the
Purchase Period in which the Participant's employment terminated; except that if
such Participant so requests prior to the last day of such Purchase Period, the
Company shall refund in cash within 15 days all amounts credited to his or her
Recordkeeping Account.

         10. PURCHASE OF SHARES.

         10.1. As of the last day of the Purchase Period, the entire credit
balance in each Participant's Recordkeeping Account will be used to purchase
shares (including fractional shares) of Common Stock (subject to the limitations
of Section 5) unless the Participant has filed an appropriate form with the
Company in advance of that date (which either elects to purchase a specified
number of shares which is less than the number described above or elects to
receive the entire credit balance in cash). Any amount in a Participant's
Recordkeeping Account that is not used to purchase shares pursuant to this
Section 10.1 will be refunded to the Participant.

         10.2. Shares of Common Stock acquired by each Participant shall be held
in a general account maintained for the benefit of all Participants.

         10.3. Certificates for the number of whole shares of Common Stock,
determined as aforesaid, purchased by each Participant shall be issued and
delivered to him or her only upon request of the Participant or his or her
representative directed to the Company. No Certificates for fractional shares
will be issued. Instead, Participants will receive a cash distribution
representing any fractional shares.

         10.4. Dividends with respect to a Participant's shares held in the
general account will, at the election of the Participant, either be paid to the
Participant in cash or reinvested in additional shares of Common Stock. If a
Participant fails to make such an election, all dividends with respect to the
Participant's shares held in the general account will automatically be
reinvested to purchase additional shares of Common Stock.

         10.5. Each Participant will be entitled to vote all shares held for the
benefit of such Participant in the general account.

         11. RIGHTS AS A STOCKHOLDER. A Participant shall not be entitled to any
of the rights or privileges of a stockholder of the Company with respect to such
shares, including the right to receive any dividends which may be declared by
the Company, until (i) he or she actually has paid the purchase price for such
shares and (ii) either the shares have been credited to his or her account or
certificates have been issued to him or her, both as provided in Section 10. A-4

         12. RIGHTS NOT TRANSFERABLE. A Participant's rights under this Plan are
exercisable only by the Participant during his or her lifetime, and may not be
sold, pledged,



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assigned or transferred in any manner other than by will or the laws of descent
and distribution. Any attempt to sell, pledge, assign or transfer the same shall
be null and void and without effect. The amounts credited to a Recordkeeping
Account may not be assigned, transferred, pledged or hypothecated in any way,
and any attempted assignment, transfer, pledge, hypothecation or other
disposition of such amounts will be null and void and without effect.

         13. ADMINISTRATION OF THE PLAN. This Plan shall be administered by the
Committee, which is authorized to make such uniform rules as may be necessary to
carry out its provisions. The Committee shall determine any questions arising in
the administration, interpretation and application of this Plan, and all such
determinations shall be conclusive and binding on all parties.

         14. ADJUSTMENT UPON CHANGES IN CAPITALIZATION. In the event of any
change in the Common Stock of the Company by reason of stock dividends,
split-ups, corporate separations, recapitalizations, mergers, consolidations,
combinations, exchanges of shares and the like, the aggregate number and class
of shares available under this Plan and the number, class and purchase price of
shares available but not yet purchased under this Plan, shall be adjusted
appropriately by the Committee.

         15. REGISTRATION OF CERTIFICATES. Stock certificates will be registered
in the name of the Participant, or jointly in the name of the Participant and
another person, as the Participant may direct on an appropriate form.

         16. AMENDMENT OF PLAN. The Board of Directors may at any time amend
this Plan in any respect which shall not adversely affect the rights of
Participants pursuant to shares previously acquired under the Plan, except that,
without stockholder approval on the same basis as required by Section 19.1, no
amendment shall be made (i) to increase the number of shares to be reserved
under this Plan, (ii) to decrease the minimum purchase price, (iii) to withdraw
the administration of this Plan from the Committee, or (iv) to change the
definition of employees eligible to participate in the Plan.

         17. EFFECTIVE DATE OF PLAN. This Plan shall consist of an offering
commencing April 1, 1996, and ending June 30, 1996, and continuing on a
quarterly basis thereafter. All rights of Participants in any offering hereunder
shall terminate at the earlier of (i) the day that Participants become entitled
to purchase a number of shares of Common Stock equal to or greater than the
number of shares remaining available for purchase or (ii) at any time, at the
discretion of the Board of Directors, after 30 days' notice has been given to
all Participants. Upon termination of this Plan, shares of Common Stock shall be
issued to Participants in accordance with Section 10, and cash, if any,
remaining in the Participant's Recordkeeping Accounts shall be refunded to them,
as if the Plan were terminated at the end of a Purchase Period.

         18. GOVERNMENTAL REGULATIONS AND LISTING. All rights granted or to be
granted to Eligible Employees under this Plan are expressly subject to all
applicable laws and regulations and to the approval of all governmental
authorities required in connection with the




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authorization, issuance, sale or transfer of the shares of Common Stock reserved
for this Plan, including, without limitation, there being a current registration
statement of the Company under the Securities Act of 1933, as amended, covering
the shares of Common Stock purchasable on the last day of the Purchase Period
applicable to such shares, and if such a registration statement shall not then
be effective, the term of such Purchase Period shall be extended until the first
business day after the effective date of such a registration A-5 statement, or
post-effective amendment thereto. If applicable, all such rights hereunder are
also similarly subject to effectiveness of an appropriate listing application to
a national securities exchange or a national market system, covering the shares
of Common Stock under the Plan upon official notice of issuance.

         19. MISCELLANEOUS.

         19.1. This Plan shall be submitted for approval by the stockholders of
the Company prior to June 30, 1996. If not so approved prior to such date, this
Plan shall terminate on June 30, 1996.

         19.2. This Plan shall not be deemed to constitute a contract of
employment between the Company and any Participant, nor shall it interfere with
the right of the Company to terminate any Participant and treat him or her
without regard to the effect which such treatment might have upon him or her
under this Plan.

         19.3. Wherever appropriate as used herein, the masculine gender may be
read as the feminine gender, the feminine gender may be read as the masculine
gender, the singular may be read as the plural and the plural may be read as the
singular.

         19.4. The Plan, and all agreements hereunder, shall be construed in
accordance with and governed by the laws of the State of Minnesota.

         19.5. Delivery of shares of Common Stock or of cash pursuant to this
Plan shall be subject to any required withholding taxes. A person entitled to
receive shares of Common Stock may, as a condition precedent to receiving such
shares, be required to pay the Company a cash amount equal to the amount of any
required withholdings.