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                                                                     Exhibit 4.3



                                     WARRANT

                    TO PURCHASE 25,000 SHARES OF COMMON STOCK
                                       OF
                               VICOM INCORPORATED


         THIS WARRANT AND THE SECURITIES ISSUABLE UPON EXERCISE OF THIS WARRANT
         HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE "1933
         ACT") OR UNDER ANY STATE SECURITIES OR "BLUE SKY" LAWS ("BLUE SKY
         LAWS"). NO TRANSFER, SALE, ASSIGNMENT, PLEDGE, HYPOTHECATION OR OTHER
         DISPOSITION OF THIS WARRANT OR THE SECURITIES ISSUABLE UPON EXERCISE OF
         THIS WARRANT OR ANY INTEREST THEREIN MAY BE MADE EXCEPT (a) PURSUANT TO
         AN EFFECTIVE REGISTRATION STATEMENT UNDER THE 1933 ACT AND ANY
         APPLICABLE BLUE SKY LAWS OR (b) IF THE CORPORATION HAS BEEN FURNISHED
         WITH AN OPINION OF COUNSEL FOR THE HOLDER, WHICH OPINION AND COUNSEL
         SHALL BE REASONABLY SATISFACTORY TO THE CORPORATION, TO THE EFFECT THAT
         NO REGISTRATION IS REQUIRED BECAUSE OF THE AVAILABILITY OF AN EXEMPTION
         FROM REGISTRATION UNDER THE 1933 ACT AND APPLICABLE BLUE SKY LAWS.


                 THIS CERTIFIES THAT, for good and valuable consideration James
L. Mandel (the "Holder"), or the Holder's registered assigns, is entitled to
subscribe for and purchase from Vicom Incorporated, a Minnesota corporation (the
"Corporation"), at any time after December 28, 1999, to and including December
27, 2004, 25,000 (Twenty Five Thousand) fully paid and nonassessable shares of
the Common Stock of the Corporation at the price of $2.00 per share (the
"Warrant Exercise Price"), subject to the anti-dilution provisions of this
Warrant.

                 The shares which may be acquired upon exercise of this Warrant
are referred to herein as the "Warrant Shares." As used herein, the term
"Holder" means the Holder, any party who acquires all or a part of this Warrant
as a registered transferee of the Holder, or any record holder or holders of the
Warrant Shares issued upon exercise, whether in whole or in part, of the
Warrant. The term "Common Stock" means the common stock, no par value per share,
of the Corporation.

                 This Warrant is subject to the following provisions, terms and
conditions:

         1.      EXERCISE; TRANSFERABILITY.

                 (a)  The rights represented by this Warrant may be exercised
by the Holder hereof, in whole or in part (but not as to a fractional share of
Common Stock), by written notice of exercise (in the form attached hereto)
delivered to the Corporation at the principal office of the Corporation prior to
the expiration of this Warrant and accompanied or preceded by the surrender

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of this Warrant along with a check in payment of the Warrant Exercise Price for
such Warrant Shares.

                 (b)  Except as provided in Section 7 hereof, this Warrant may
not be sold, transferred, assigned, hypothecated or divided into two or more
Warrants of smaller denominations, nor may any Warrant Shares issued pursuant to
exercise of this Warrant be transferred.

         2.      EXCHANGE AND REPLACEMENT.  Subject to Sections 1 and 7 hereof,
this Warrant is exchangeable upon the surrender hereof by the Holder to the
Corporation at its office for new Warrants of like tenor and date representing
in the aggregate the right to purchase the number of Warrant Shares purchasable
hereunder, each of such new Warrants to represent the right to purchase such
number of Warrant Shares (not to exceed the aggregate total number purchasable
hereunder) as shall be designated by the Holder at the time of such surrender.
Upon receipt by the Corporation of evidence reasonably satisfactory to it of the
loss, theft, destruction, or mutilation of this Warrant, and, in case of loss,
theft or destruction, of indemnity or security reasonably satisfactory to it,
and upon surrender and cancellation of this Warrant, if mutilated, the
Corporation will make and deliver a new Warrant of like tenor, in lieu of this
Warrant. This Warrant shall be promptly canceled by the Corporation upon the
surrender hereof in connection with any exchange or replacement. The Corporation
shall pay all expenses, taxes (other than stock transfer taxes), and other
charges payable in connection with the preparation, execution, and delivery of
Warrants pursuant to this Section 2.

         3.      ISSUANCE OF THE WARRANT SHARES.

                 (a)  The Corporation agrees that the Warrant Shares shall be
and are deemed to be issued to the Holder as of the close of business on the
date on which this Warrant shall have been surrendered and the payment made for
such Warrant Shares as aforesaid. Subject to the provisions of paragraph (b) of
this Section 3, certificates for the Warrant Shares so purchased shall be
delivered to the Holder within a reasonable time after the rights represented by
this Warrant shall have been so exercised, and, unless this Warrant has expired,
a new Warrant representing the right to purchase the number of Warrant Shares,
if any, with respect to which this Warrant shall not then have been exercised
shall also be delivered to the Holder.

                 (b)  Notwithstanding the foregoing, however, the Corporation
shall not be required to deliver any certificate for Warrant Shares upon
exercise of this Warrant except in accordance with exemptions from the
applicable securities registration requirements or registrations under
applicable securities laws. Nothing herein shall obligate the Corporation to
effect registrations under federal or state securities laws. If registrations
are not in effect and if exemptions are not available when the Holder seeks to
exercise the Warrant, the Warrant exercise period will be extended, if need be,
to prevent the Warrant from expiring, until such time as either registrations
become effective or exemptions are available, and the Warrant shall then remain
exercisable for a period of at least 30 calendar days from the date the
Corporation delivers to the Holder written notice of the availability of such
registrations or exemptions. The Holder agrees to execute such documents and
make such representations, warranties, and


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agreements as may be required solely to comply with the exemptions relied upon
by the Corporation, or the registrations made, for the issuance of the Warrant
Shares.

         4.      COVENANTS OF THE CORPORATION.  The Corporation covenants and
agrees that all Warrant Shares will, upon issuance, be duly authorized and
issued, fully paid, non-assessable and free from all taxes, liens and charges
with respect to the issue thereof. The Corporation further covenants and agrees
that during the period within which the rights represented by this Warrant may
be exercised, the Corporation will at all times have authorized and reserved
for the purpose of issue or transfer upon exercise of the subscription rights
evidenced by this Warrant a sufficient number of shares of Common Stock to
provide for the exercise of the rights represented by this Warrant.

         5.      ANTI-DILUTION ADJUSTMENTS.  The provisions of this Warrant are
subject to adjustment as provided in this Section 5.

                 (a)     The Warrant Exercise Price shall be adjusted from time
to time such that in case the Corporation shall hereafter:

                         (i)  pay any dividends on any class of stock of the
         Corporation payable in Common Stock or securities convertible into
         Common Stock;

                         (ii)  subdivide its then outstanding shares of Common
         Stock into a greater number of shares; or

                         (iii)  combine outstanding shares of Common Stock, by
         reclassification or otherwise;

then, in any such event, the Warrant Exercise Price in effect immediately prior
to such event shall (until adjusted again pursuant hereto) be adjusted
immediately after such event to a price (calculated to the nearest full cent)
determined by dividing (A) the number of shares of Common Stock outstanding
immediately prior to such event, multiplied by the then existing Warrant
Exercise Price, by (B) the total number of shares of Common Stock outstanding
immediately after such event (including in each case the maximum number of
shares of Common Stock issuable in respect of any securities convertible into
Common Stock), and the resulting quotient shall be the adjusted Warrant Exercise
Price per share. An adjustment made pursuant to this Subsection shall become
effective immediately after the record date in the case of a dividend or
distribution and shall become effective immediately after the effective date in
the case of a subdivision, combination or reclassification. If, as a result of
an adjustment made pursuant to this Subsection, the Holder of any Warrant
thereafter surrendered for exercise shall become entitled to receive shares of
two or more classes of capital stock or shares of Common Stock and other capital
stock of the Corporation, the Board of Directors (whose determination shall be
conclusive) shall determine the allocation of the adjusted Warrant Exercise
Price between or among shares of such classes of capital stock or shares of
Common Stock and other capital stock. All calculations under this Subsection
shall be made to the nearest cent or to the nearest 1/100 of a share, as the
case may be. In the event that at any time as a result of an adjustment made


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pursuant to this Subsection, the holder of any Warrant thereafter surrendered
for exercise shall become entitled to receive any shares of the Corporation
other than shares of Common Stock, thereafter the Warrant Exercise Price of such
other shares so receivable upon exercise of any Warrant shall be subject to
adjustment from time to time in a manner and on terms as nearly equivalent as
practicable to the provisions with respect to Common Stock contained in this
Section.

                 (b)  Upon each adjustment of the Warrant Exercise Price
pursuant to Section 5(a) above, the Holder of each Warrant shall thereafter
(until another such adjustment) be entitled to purchase at the adjusted Warrant
Exercise Price the number of shares, calculated to the nearest full share,
obtained by multiplying the number of shares specified in such Warrant (as
adjusted as a result of all adjustments in the Warrant Exercise Price in effect
prior to such adjustment) by the Warrant Exercise Price in effect prior to such
adjustment and dividing the product so obtained by the adjusted Warrant Exercise
Price.

                 (c)  In case of any consolidation or merger to which the
Corporation is a party other than a merger or consolidation in which the
Corporation is the continuing corporation, or in case of any sale or conveyance
to another corporation of the property of the Corporation as an entirety or
substantially as an entirety, or in the case of any statutory exchange of
securities with another corporation (including any exchange effected in
connection with a merger of a third corporation into the Corporation), there
shall be no adjustment under Subsection (a) of this Section 5 but the Holder of
each Warrant then outstanding shall have the right thereafter to convert such
Warrant into the kind and amount of shares of stock and other securities and
property which he would have owned or have been entitled to receive immediately
after such consolidation, merger, statutory exchange, sale, or conveyance had
such Warrant been converted immediately prior to the effective date of such
consolidation, merger, statutory exchange, sale, or conveyance and, in any such
case, if necessary, appropriate adjustment shall be made in the application of
the provisions set forth in this Section with respect to the rights and
interests thereafter of any Holders of the Warrant, to the end that the
provisions set forth in this Section shall thereafter correspondingly be made
applicable, as nearly as may reasonably be, in relation to any shares of stock
and other securities and property thereafter deliverable on the exercise of the
Warrant. The provisions of this Subsection shall similarly apply to successive
consolidations, mergers, statutory exchanges, sales or conveyances.

                 (d)  Upon any adjustment of the Warrant Exercise Price, then
and in each such case, the Corporation shall give written notice thereof, by
first-class mail, postage prepaid, addressed to the Holder as shown on the books
of the Corporation, which notice shall state the Warrant Exercise Price
resulting from such adjustment and the increase or decrease, if any, in the
number of shares of Common Stock purchasable at such price upon the exercise of
this Warrant, setting forth in reasonable detail the method of calculation and
the facts upon which such calculation is based.

         6.      NO VOTING RIGHTS.  This Warrant shall not entitle the Holder to
any voting rights or other rights as a shareholder of the Corporation.


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         7.      NOTICE OF TRANSFER OF WARRANT OR RESALE OF THE WARRANT SHARES.

                 (a)  Subject to the sale, assignment, hypothecation, or other
transfer restrictions set forth in Section 1 hereof, the Holder, by acceptance
hereof, agrees to give written notice to the Corporation before transferring
this Warrant or transferring any Warrant Shares of such Holder's intention to do
so, describing briefly the manner of any proposed transfer. Promptly upon
receiving such written notice, the Corporation shall present copies thereof to
the Corporation's counsel. If in the opinion of such counsel the proposed
transfer may be effected without registration or qualification (under any
federal or state securities laws), the Corporation, as promptly as practicable,
shall notify the Holder of such opinion, whereupon the Holder shall be entitled
to transfer this Warrant or to dispose of Warrant Shares received upon the
previous exercise of this Warrant, all in accordance with the terms of the
notice delivered by the Holder to the Corporation; provided that an appropriate
legend may be endorsed on this Warrant or the certificates for such Warrant
Shares respecting restrictions upon transfer thereof necessary or advisable in
the opinion of counsel and satisfactory to the Corporation to prevent further
transfers which would be in violation of Section 5 of the 1933 Act and
applicable state securities laws; and provided further that the prospective
transferee or purchaser shall execute such documents and make such
representations, warranties, and agreements as may be required solely to comply
with the exemptions relied upon by the Corporation for the transfer or
disposition of the Warrant or Warrant Shares.

                 (b)  If, in the opinion of the Corporation's counsel, the
proposed transfer or disposition of this Warrant or such Warrant Shares
described in the written notice given pursuant to this Section 7 may not be
effected without registration or qualification of this Warrant or such Warrant
Shares, the Corporation shall promptly give written notice thereof to the
Holder, and the Holder will limit its activities in respect to such transfer or
disposition as, in the opinion of such counsel, are permitted by law.

         8.      FRACTIONAL SHARES.  Fractional shares shall not be issued upon
the exercise of this Warrant, but in any case where the holder would, except for
the provisions of this Section, be entitled under the terms hereof to receive a
fractional share, the Corporation shall, upon the exercise of this Warrant for
the largest number of whole shares then called for, pay a sum in cash equal to
the sum of (a) the excess, if any, of the Market Price of such fractional share
over the proportional part of the Warrant Exercise Price represented by such
fractional share, plus (b) the proportional part of the Warrant Exercise Price
represented by such fractional share. For purposes of this Section, the term
"Market Price" with respect to shares of Common Stock of any class or series
means the last reported sale price or, if none, the average of the last reported
closing bid and asked prices on any national or regional securities exchange or
quoted in the National Association of Securities Dealers, Inc.'s Automated
Quotations System ("Nasdaq"), or if not listed on a national or regional
securities exchange or quoted in Nasdaq, the average of the last reported
closing bid and asked prices as reported by Metro Data Corporation, Inc. or the
Electronic Bulletin Board of the National Association of Securities Dealers,
Inc. from quotations by market makers in such Common Stock on the
Minneapolis-St. Paul local over-the-counter market, or if no quotations in such
Common Stock are available, the fair market value of the shares as determined in
good faith by the Board of Directors of the Corporation.


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         9.      REGISTRATION RIGHTS.

                 (a)  INCIDENTAL REGISTRATION.  If the Corporation at any time
within five (5) years from the date of this Warrant proposes to register under
the 1933 Act any of its securities on Forms S-1, S-2, SB-2, or S-3, or on any
successor or similar form of Registration Statement (EXCEPT with respect to the
first public offering of securities by the Corporation pursuant to a
registration statement filed under the 1933 Act after the date of this Warrant),
it will give written notice to all Holders of this Warrant, any Warrants issued
pursuant to Section 2 and/or Section 3(a) hereof, and any Warrant Shares of its
intention to do so, and on the written request of any such Holder given within
twenty (20) calendar days after receipt of any such notice (which request shall
specify the Warrant Shares intended to be sold or disposed of by such Holder),
the Corporation will use its best efforts to cause all such Warrant Shares, the
Holders of which shall have requested the registration or qualification thereof,
to be included in such registration statement proposed to be filed by the
Corporation; provided, however, that if a greater number of Warrant Shares is
offered for participation in the proposed offering than in the reasonable
opinion of the managing underwriter of the proposed offering (which opinion
shall be in writing and delivered to the Holders) can be accommodated without
adversely affecting the proposed offering, then the amount of Warrant Shares
proposed to be offered by such Holders for registration, as well as the number
of securities of any other selling shareholders participating in the
registration, shall not be included or shall be proportionately reduced to a
number deemed satisfactory by the managing underwriter. With respect to each
inclusion of securities in a registration statement pursuant to this Section
9(a), the selling Holders shall pay the fees and disbursements of special
counsel and accountants for the selling Holders, and underwriting discounts or
commissions and transfer taxes applicable to the selling Holders' shares, and
the Corporation shall pay all other costs and expenses of the registration,
including but not limited to all registration, filing and NASD fees, printing
expenses, fees and disbursements of counsel and accountants for the Corporation,
all internal expenses, and legal fees and disbursements and other expenses of
complying with state securities laws of any jurisdictions in which the
securities to be offered are to be registered or qualified. Holders who elect to
include their Warrants Shares in a registration pursuant to this Section 9(a)
shall participate in the registered offering on the same terms as the
Corporation.

                 (b)  DEMAND REGISTRATION.  Further, on a one-time basis only,
during the period commencing on the date of this Warrant and ending five (5)
years after the date of this Warrant, provided that the Corporation then is
eligible to use a Registration Statement on Form S-3 or any equivalent form of
short-form registration statement for the registration of the sale of the
Warrant Shares pursuant to the 1933 Act, upon request by the Holder or Holders,
the Corporation will promptly take all necessary steps to register under the
1933 Act on Form S-3 or equivalent form of short-form registration statement and
under the securities laws of such states as the holders may reasonably request,
such number of Warrant Shares issued and to be issued upon exercise of the
Warrants requested by such Holders in their request to the Corporation. After a
demand for registration has been made by a Holder or Holders of the requisite
number of Warrants or Warrant Shares, the Corporation will give written notice
of the demand registration to all Holders of Warrants or Warrant Shares and, on
the written request of any such Holder given within twenty (20) calendar days
after receipt of any such notice (which request shall specify the Warrant Shares


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intended to be sold or disposed of by such Holder), the Corporation will cause
all such Warrant Shares, the Holders of which shall have requested the
registration or qualification thereof, to be included in such demand
registration statement. Notwithstanding anything in this Warrant to the
contrary, the Corporation shall not be obligated to register the Warrant Shares
under this Section 9(b) unless Holders who hold more than fifty percent (50%) of
the total number of Warrants issued as part of the Series of Warrants and of any
shares acquired upon exercise of such Warrants request such registration. With
respect to a demand registration statement pursuant to this Section 9(b), the
selling Holders shall pay the fees and disbursements of special counsel and
accountants for the selling Holders, and underwriting discounts or commissions
and transfer taxes applicable to the selling Holders' shares, and the
Corporation shall pay all other costs and expenses of the registration,
including but not limited to all registration, filing and NASD fees, printing
expenses, fees and disbursements of counsel and accountants for the Corporation,
all internal expenses, and legal fees and disbursements and other expenses of
complying with state securities laws of any jurisdictions in which the
securities to be offered are to be registered or qualified. The Corporation
shall keep effective and maintain any registration, qualification, notification,
or approval specified in this Section 9(b) for such period as may be reasonably
necessary for such Holder or Holders of such Warrant Shares to dispose thereof
and from time to time shall amend or supplement the prospectus used in
connection therewith to the extent necessary in order to comply with applicable
law. The Corporation need not maintain the effectiveness of any such
registration, qualification, notification or approval, whether or not at the
request of the Holders, more than six (6) months following the effective date
thereof.

                 (c)  COOPERATION.  Upon the exercise of registration rights
pursuant hereto, each holder agrees to supply the Corporation with such
information as may be required by the Corporation to register or qualify the
shares to be registered.

         10.     REDEMPTION.  The Warrants may be redeemed by the Corporation,
in whole or in part, at a redemption price of $0.01 per Warrant (subject to
appropriate adjustment as determined by the Corporation's Board of Directors in
the event of the occurrence of the events described in Sections 5(a)(i), (ii)
and (iii)) upon notice of such redemption given by the Corporation not less than
thirty (30) days prior to the date fixed for redemption mailed to the holders of
Warrants at their last registered addresses. The Corporation shall be entitled
to redeem the Warrants as provided in this Section 10 only if the closing bid
price of the Common Stock exceeds $4.00 per share (subject to appropriate
adjustment as determined by the Corporation's Board of Directors in the event of
the occurrence of the events described in Sections 5(a)(i), (ii) and (iii)) for
any ten (10) consecutive trading days prior to such notice. If notice of
redemption shall have been given to the Holders, the exercise rights of the
Warrants identified for redemption shall expire at the close of business on such
date of redemption, unless extended by the Corporation.


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                  IN WITNESS WHEREOF, Vicom Incorporated has caused this Warrant
to be signed by its duly authorized officer and this Warrant to be dated
___________, 199__.



                                                 Vicom Incorporated



                                                 -------------------------------
                                                 Chief Executive Officer



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   (To Be Executed by the Registered Holder in Order to Exercise the Warrant)


To:    Vicom Incorporated


The undersigned hereby irrevocably elects to exercise the attached Warrant to
purchase for cash, ________________ of the shares issuable upon the exercise of
such Warrant, and requests that certificates for such shares (together with a
new Warrant to purchase the number of shares, if any, with respect to which this
Warrant is not exercised) shall be issued in the name of:


                             NAME:           __________________________________

                             SOC. SEC. or
                             TAX I.D. NO.    __________________________________


                             ADDRESS:        __________________________________


                                             __________________________________



Date: _________, 19___.                      __________________________________
                                             Signature *



   *     The signature on the Notice of Exercise of Warrant must correspond to
         the name as written upon the face of the Warrant in every particular
         without alteration or enlargement or any change whatsoever. When
         signing on behalf of a corporation, partnership, trust or other entity,
         please indicate your position(s) and title(s) with such entity.

<PAGE>

                                 ASSIGNMENT FORM

   (To be Executed by the Registered Holder in Order to Transfer the Warrant)


To:    Vicom Incorporated


       FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and transfers
unto ___________________________ the right to purchase the securities of Vicom
Incorporated, Inc. to which the within Warrant relates and appoints ___________,
attorney, to transfer said right on the books of Vicom, Incorporated with full
power of substitution in the premises.


Dated: _________________.                   ______________________________
                                            (Signature)

                                            Address:

                                            ______________________________


                                            ______________________________