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                                                                     Exhibit 4.2

                                                           Certificate No. W-___

                                    WARRANT

                 TO PURCHASE __________ 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
_______________ (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 ___________, 199_, to and including
____________, 200_, ___________ (____________) fully paid and nonassessable
shares of the Common Stock of the Corporation at the price of $3.00 per share
(the "Warrant Exercise Price"), subject to the antidilution 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 part of a series of
Warrants (the "Series") issued in connection with a private placement by the
Corporation pursuant to the Corporation's Confidential Private Placement
Memorandum dated December 9, 1998.

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

         1. EXERCISE; TRANSFERABILITY.

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                  (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 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


                                      -2-
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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 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, nonassessable 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

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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 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,


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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 the 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
three (3) 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, 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 three (3) 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




                                     -9-

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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.

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                                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:

                                            ---------------------------------

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