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                                                                     Exhibit 4.9


                               VICOM, INCORPORATED

                           CERTIFICATE OF DESIGNATION
                                     OF THE
                  RELATIVE RIGHTS, RESTRICTIONS AND PREFERENCES
                                                        OF
               14% CLASS D CUMULATIVE CONVERTIBLE PREFERRED STOCK

     Pursuant to Section 302A.401 of the Minnesota Business Corporations Act

                                   ----------

     The undersigned, as the Chief Executive Officer of Vicom, Incorporated, a
Minnesota corporation (the "Corporation"), hereby certifies that on the 17th day
of November, 2000, the following resolutions were adopted by the Board of
Directors of the Corporation for the purpose of designating a portion of the
Corporation's authorized but unissued capital stock as Preferred Stock and
establishing a fourth class of Preferred Stock designated as "14% Class D
Cumulative Convertible Preferred Stock":


     "RESOLVED, that pursuant to authority granted to and vested in the Board of
Directors by the laws of the State of Minnesota and the Corporation's Articles
of Incorporation, as amended and restated, the Board of Directors hereby
establishes the following classes of capital stock:

     A.   Two Hundred Fifty Thousand (250,000) shares of the Corporation's
          authorized but unissued capital stock shall be Preferred Stock, with
          no par value per share, designated as "14% Class D Cumulative
          Convertible Preferred Stock";

     B.   The remaining balance of the Corporation's authorized but unissued
          capital stock shall be undesignated as to class or series.

     FURTHER RESOLVED, that the 14% Class D Cumulative Convertible Preferred
     Stock shall have the relative right, restrictions and preferences set forth
     in Appendix A attached hereto."

     IN WITNESS WHEREOF, I have hereunder subscribed my name this 17th day of
     November, 2000.

                                                     /s/James L. Mandel
                                                     -------------------------
                                                     Chief Executive Officer


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                                   APPENDIX A


                               VICOM, INCORPORATED

               14% CLASS D CUMULATIVE CONVERTIBLE PREFERRED STOCK


     The total number of shares of all classes of capital stock which the
Corporation is authorized to issue is Fifty Million (50,000,000). The shares of
capital stock of the Corporation shall include a class of preferred stock
consisting of Two Hundred Seventy-five Thousand (275,000) shares, which shall be
designated 8% Class A Cumulative Convertible Preferred Stock with no par value
per share ("Class A Preferred"), and a second class of preferred stock
consisting of Sixty Thousand (60,000) shares, which shall be designated 10%
Class B Cumulative Convertible Preferred Stock with no par value per share
("Class B Preferred") a third class of Preferred Stock consisting of 250,000
shares, which shall be designated as 10% Class C ("Class C") Cumulative
Convertible Preferred Stock, and a fourth class of Preferred Stock consisting of
two hundred fifty thousand (250,000) shares which shall be designated 14% Class
D Cumulative Convertible Preferred Stock. The balance of the Corporation's
authorized but unissued capital stock shall be undesignated capital stock. The
rights, preferences, privileges, restrictions and other matters relating to the
Class D Preferred Stock are as follows:

     1. Dividends. Holders of the Class D Preferred shall be entitled to
     receive, when and as declared by the Board of Directors out of funds
     legally available therefor, cumulative cash dividends at the rate set forth
     below in paragraph 1A. For purposes of calculating the dividends payable on
     the Class D Preferred, each share of Class D Preferred shall be valued at
     $10.00 per share approximately adjusted for stock dividends, stock splits,
     reverse stock splits, and other subdivisions and combinations of Class D
     Preferred (such per share price, as it may be adjusted, for the Class D
     Preferred is referred to herein as the "Dividend Price"). All dividends
     payable pursuant to this Section 1 shall be referred to as "Preferred
     Dividends."

          A. Class D Preferred. The holders of shares of Class D Preferred shall
          be entitled to receive, when and as declared by the Board of Directors
          of the Corporation out of assets of the Corporation legally available
          for payment thereof, cumulative cash dividends on the Dividend Price
          then in effect for the Class D Preferred at the per annum rate,
          computed on the basis of actual days over a 365-day year, of fourteen
          percent (14%) per annum. Such dividends shall be payable upon
          declaration quarterly on March 31, June 30, September 30 and December
          31 of each year, commencing for any share of Class D Preferred on the
          first of such dates to occur after that share is issued.

          B. Accrual; Payment. The Preferred Dividends on the Class D Preferred
          shall accrue cumulatively on a daily basis from and as of the date of
          original issuance of the Class D Preferred until such time as the
          Class D Preferred are redeemed or converted, whether or not declared
          and whether or not any funds of the Corporation are legally available
          for the payment of dividends. Preferred Dividends shall be payable to
          holders of record of the Class D Preferred as they appear on the books
          of the Corporation on the record date determined by the Board of
          Directors. Preferred Dividends payable for the initial dividend period
          shall be based on the amount of dividends accrued since the date of
          issuance of the Class D Preferred.

     2. Dividend Priorities. No dividend payments shall be paid or declared and
set apart for payment on any other shares of stock of the Corporation, whether
common or preferred, for any period, and no other shares of the Corporation,
whether common or preferred, shall be redeemed or purchased by the Corporation,
unless all Preferred Dividends have been paid or contemporaneously are declared
and paid on the Class D Preferred for such period. Except as provided in
Section1 above, holders of the Class D Preferred shall not be entitled to any
dividends, whether payable in cash, property or stock, in excess of the full
Preferred Dividends for any period. No interest, or sum of money in lieu of
interest, shall be payable in respect of any Preferred Dividend payments or
payment which may be in arrears. If at any time

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the Corporation pays less than the total amount of the Preferred Dividends then
accrued with respect to the Class D Preferred, such payment shall be distributed
ratably among the holders of Class D Preferred based upon the aggregate accrued
but unpaid dividends on the shares of Class D Preferred held by each such holder
on the record date fixed by the Board of Directors for the payment of such
dividend. The Board of Directors, in its discretion, may declare and pay
dividends on the common stock or capital stock of the Corporation, provided that
all accumulated Preferred Dividends on the Class D Preferred for the current and
all previous dividend periods have been paid in full. In the event that, for a
given year, the dividends declared on the common stock of the Corporation
exceed, on a per share basis, the year to date per share Preferred Dividends
accrued, declared and paid on the Class D Preferred, the Class D Preferred shall
participate in and shall receive a pro rate share of the excess amount. Such
allocation shall be adjusted as appropriate to account for any change in the
capitalization of the Corporation occurring after the date hereof, whether
resulting from a recapitalization, stock dividend, stock split, reverse stock
split or otherwise.

   3. Liquidation Preferences.

     A. Upon any liquidation, dissolution or winding up of the Corporation,
whether voluntary or involuntary, the holders of the shares of Class D Preferred
shall be entitled, after payment or provision for all debts and liabilities of
the Corporation and before any distribution or payment is made upon any other
shares of capital stock of the Corporation, to be paid an amount per share equal
to the sum of (i) $10.00 per share (appropriately adjusted for stock dividends,
stock splits, reverse stock splits, and other subdivisions and combinations of
Class D Preferred (such per share price, as adjusted, for the Class D Preferred
is referred to herein as the "Preferred Price") plus (ii) accrued and unpaid
Preferred Dividends due under Section 1 above. (Such total sum of the amounts
payable referred to in clauses (i) and (ii) being sometimes referred to herein
as the "Preferential Amount".) If upon such liquidation, dissolution or winding
up of the Corporation, whether voluntary or involuntary, the assets to be
distributed among the holders of Class D Preferred shall be insufficient to
permit payment to the holders of Class D Preferred of the amount distributable
as aforesaid, then all of the assets of the Corporation remaining to be so
distributed ratably (a) first among the holders of the shares of Class D
Preferred so that the same percentage of the Preferred Price for each share of
Class D Preferred is paid with respect to each such share, until the full amount
of the Preferred Price has been paid; and (b) then among the holders of the
shares of Class D Preferred so that the same percentage of the Preferred
Dividends for each share of Class D Preferred is paid with respect to each such
share, until the full amount of the Preferred Dividends has been paid.

     B. Upon any such liquidation, dissolution or winding up of the Corporation,
after the holders of Class D Preferred shall have been fully paid in full the
amounts to which they shall be entitled, the remaining net assets of the
Corporation may be distributed pro rate to the holders of shares of common stock
of the Corporation; provided that in the event that, upon liquidation and
dissolution of the Corporation, the amounts distributed to the holders of the
shares of common stock of the Corporation exceed, on a per share basis, the
amount of the Preferential Amount, the holders of the Class D Preferred shall
participate in and shall receive a pro rate share of the excess.

     C. Written notice of such liquidation, dissolution or winding up, stating a
payment date, the amount of the Preferential Amount and the place where said
Preferential Amount shall be payable, shall be delivered in person, mailed by
certified or registered mail, return receipt requested, or sent by telecopier or
telex, not less than twenty (20) business days prior to the payment date stated
therein, to the holders of record of Class D Preferred, such notice to be
addressed to each such holder at its address as shown by the records of the
Corporation. The consolidation or merger of the Corporation into or with any
other securitie4s or other consideration issued or paid or caused to be issued
or paid by any such entity or affiliate thereof, and the sale, lease,
abandonment, transfer or other disposition by the Corporation of all or
substantially all its assets, shall be deemed to be a liquidation, dissolution
or winding up of the Corporation within the meaning of the provisions of this
Section


   4. Voting Rights. The Class D Preferred are non-voting, except as may
otherwise be required by law.

   5. Conversions. The holders of shares of Class D Preferred shall have the
following conversion rights:

     A. Right to Convert. Subject to the terms and conditions of this Section 5,
the holder of any share of shares of Class

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D Preferred shall have the right, at his or her option at any time, to convert
any such share or shares of Class D Preferred (except that upon any liquidation
of the Corporation the right of conversion shall terminate at the close of
business on the business day prior to the date fixed for payment of the amount
distributable on Class D Preferred into two and one-half (2 1/2) fully paid and
nonassessable shares of the Corporation's common stock, no par value per share
(the "Common Stock"), or, in case an adjustment has taken place pursuant to the
further provisions of this Section 5, then by the conversion ratio as last
adjusted and in effect at the date any share of shares of Class D Preferred are
surrendered for conversion (such ratio, or such ratio as last adjusted, being
referred to as the "Conversion Ratio"). Such rights of conversion shall be
exercised by the holder thereof by giving written notice that the holder elects
to convert a stated number of shares of Class D Preferred into Common Stock and
by surrender of a certificate or certificates for the shares so to be converted
to the Corporation at its principal office (or such other office or agency of
the Corporation as the Corporation may designate by notice in writing to the
holders of Class D Preferred) at any time during its usual business hours on the
date set forth in such notice, together with a statement of the name or names
(with address) in which the certificate or certificates for shares of Common
Stock shall be issued.

     B. Issuance of Certificates; Time Conversion Effected. Promptly after the
receipt of the written notice referred to in paragraph 5A and surrender of the
certificate or certificates for the share of shares of Class D Preferred to be
converted, the Corporation shall issue and deliver, or cause to be issued and
delivered, to the holder, registered in such name or names as such holder may
direct, a certificate or certificates for the number of whole shares of Common
Stock issuable upon the conversion of such share of shares of Class D Preferred.
The extent permitted by law, such conversion shall be deemed to have been
effected and the Conversion Ratio shall be determined as of the close of
business on the date on which such written notice shall been received by the
Corporation and the certificate or certificates for such share or shares shall
have been surrendered as aforesaid, and at such time the rights of the holder of
such share of shares of Class D Preferred shall cease, and the person or persons
in whose name or names any certificate for shares of Common Stock shall be
deemed to have become the holder and holders of record of the shares represented
thereby.

     C. Fractional Shares; Dividends; Partial Conversion. No fractional shares
shall be issued upon conversion of Class D Preferred into Common Stock and no
payment or adjustment shall be made upon any conversion on account of any cash
dividends on the Common Stock issued upon such conversion. At the time of each
conversion, the Corporation shall pay in cash an amount equal to all dividends
declared pursuant to Section 1 above and unpaid on the shares of Class D
Preferred surrendered for conversion to the date upon which such conversion is
deemed to take place as provided in paragraph 5B. In case the number of shares
of Class D Preferred represented by this certificate or certificates surrendered
pursuant to Paragraph 5A exceeds the number of shares converted the Corporation
shall, upon the conversion, execute and deliver to the holder, at the expense of
the Corporation, a new certificate of certificates for the number of shares of
Class D Preferred represented by the certificate or certificates surrendered
which are not to be converted. If any fractional share of Common Stock would,
except for the provisions of the first sentence of this paragraph 5C, be
delivered upon such conversion, the Corporation, in lieu of delivering such
fractional share, shall pay to the holder surrendering Class D Preferred for
conversion an amount in cash equal to the current market price of such
fractional share as determined in good faith by the Board of Directors of the
Corporation.

     D. Stock Dividends; Subdivision or Combination of Common Stock. In case the
Corporation shall, after the date on which the Class D Preferred are first
issued by the Corporation (the "Original Issue Date"), at any time subdivide (by
any stock split, stock dividend or otherwise) its outstanding shares of Common
Stock into a greater number of shares, the Conversion Ratio in effect
immediately prior to such subdivision shall be proportionately increased, and,
conversely, in case the outstanding shares of Common Stock shall be combined
into a smaller number of shares, the Conversion Ratio in effect immediately
prior to such combination shall be proportionately reduced.

     E. Reorganization or Reclassification. If any capital reorganization or
reclassification of the capital stock of the Corporation shall be effected after
the Original Issue Date in such a way that holders of Common Stock shall be
entitled to receive stock, securities or assets with respect to or in exchange
for Common Stock, then, as a condition of such reorganization or
reclassification, lawful and adequate provisions shall be made whereby each
holder of a share or shares of Class D Preferred shall thereupon have the right
to receive, upon the basis and upon the terms and conditions specified herein
and in lieu of the shares of Common Stock immediately theretofore receivable
upon the conversion of such share of shares of Class D Preferred, such shares of
stock, securities or assets as may be issued or payable with respect to or in
exchange for a number of outstanding share of such Common Stock equal to the
number of shares of such Common Stock immediately theretofore receivable upon
such conversion had such reorganization or reclassification not taken place,

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and in any such case appropriate provisions shall be made with respect to the
rights and interest of such holder to that end that the provisions (including,
without limitation, provisions for adjustments of the Conversion Ratio) shall
thereafter be applicable, as nearly as may be, in relation to any shares of
stock, securities or assets thereafter deliverable upon the exercise of such
conversion rights.

     F. Notice of Adjustment. Upon any adjustment of the Conversion Ratio, then
and in each such case the Corporation shall give written notice thereof, by
delivery in person, certified or registered mail, return receipt requested,
telecopier or telex, addressed to each holder of shares of Class D Preferred at
the address of such holder as shown on the books of the Corporation, which
notice shall state the Conversion Ratio resulting from such adjustment, setting
forth in reasonable detail the method upon which such calculation is based.

     G. Other Notices. In case at any time:

          (1) the Corporation shall declare any dividend upon its Common Stock
     payable in stock or make any other distribution to the holders of its
     Common Stock;

          (2) the Corporation shall offer for subscription pro rate to the
     holders of its Common Stock any additional shares of stock of any class or
     other rights;

          (3) there shall by any capital reorganization or reclassification of
     the capital stock of the Corporation, or a consolidation merger of the
     Corporation with or into another entity or entities, or a sale, lease,
     abandonment, transfer or other disposition of all or substantially all its
     assets; or

          (4) there shall be a voluntary or involuntary dissolution, liquidation
     or winding up of the Corporation;

then, in any one or more of said cases, the Corporation shall give, by delivery
in person, certified or registered mail, return receipt requested, telecopier or
telex, addressed to each holder of any shares of Class D Preferred at the
address of such holder as shown on the books of the Corporation, (a) at least 20
days' prior written notice of the date on which the books of the Corporation
shall close or a record shall be taken for such dividend, distribution or
subscription righ5ts or for determining rights to vote in respect of any such
reorganization, reclassification, consolidation, merger, disposition,
dissolution, liquidation or winding up and (b) in the case of any such
reorganization, reclassification, consolidation, merger, disposition,
dissolution, liquidation or winding up, at least 20 days' prior written notice
of the date when the same shall take place. Such notice in accordance with the
foregoing clause (a) shall also specify, in the case of any such dividend,
distribution or subscription rights, the date on which the holders of Common
Stock shall be entitled thereto and such notice in accordance with the foregoing
clause (b) shall also specify the date on which the holders of Common Stock
shall be entitled to exchange their Common Stock for securities or other
property deliverable upon such reorganization, reclassification, consolidation,
merger, disposition, dissolution, liquidation or winding up, as the case may
be..

     H. Stock to be Reserved. The Corporation will at all times reserve and keep
available out of its authorized Common Stock, solely for the purpose of issuance
upon the conversion of Class D Preferred as herein provided, such number of
shares of Common Stock as shall then be issuable upon the conversion of all
outstanding shares of Class D Preferred. The Corporation covenants that all
shares of Common Stock which shall be so issued shall by duly and validly issued
and fully paid and non assessable and free from all transfer taxes, liens and
charges with respect to the issue thereof. The Corporation will take all such
action as may be necessary to assure that all such shares of Common Stock may be
so issued without violation of any applicable law or regulation, of if any
requirement of any national securities exchange upon which the Common Stock may
be listed.

     I. No Reissuance of Class D Preferred. Shares of Class D Preferred which
are converted into shares of Common Stock as provided herein shall not be
reissued.

     J. Issue Tax. The issuance of certificates of shares of Common Stock upon
conversion of Class D Preferred shall be made without charge to the holders
thereof for any issuance tax in respect thereof, provided that the Corporation
shall not be required to pay any tax which may be payable in respect of any
transfer involved in the issuance

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and delivery of any certificate in a name other than that of the holder of Class
D Preferred which is being converted.

     K. Closing of Books. Except as required by an underwriter in connection
with a public offering, the Corporation will at no time close its transfer books
against the transfer of any Class D Preferred or of any shares of Common Stock
issued or issuable upon the conversion of any shares of Class D Preferred in any
manner which interferes with the timely conversion of such Class D Preferred
except as may otherwise be required to comply with applicable securities laws.

   6. Redemption. The Corporation shall have the right to redeem the
outstanding shares of Class D Preferred, in whole or part, at a redemption price
of $10.00 per share (appropriately adjusted for stock dividends, stock splits,
reverse stock splits, and other subdivisions and combinations of Class D
Preferred) plus any earned and unpaid Preferred Dividends, on not less than
thirty (30) calendar days' notice ("Corporate Notice") to the holders of the
Class D Preferred. The Corporation shall be entitled to redeem the Class D
Preferred as provided in this Paragraph 6 only if the closing price of the
Common Stock exceeds $4.00 per share (appropriately adjusted for stock
dividends, stock splits, reverse stock splits and other subdivisions and
combinations of Common Stock) for any ten (10) consecutive trading days prior to
the date of the Corporate Notice. Upon receipt of the Corporate Notice, the
holders of the Class D Preferred to be redeemed will have the option to convert
each share of Class D Preferred and Class B Preferred into two and one-half (2
1/2) shares of Common Stock (subject to adjustment as set forth in Section 5
above) until the close of business on the date fixed for redemption, unless
extended by the Corporation in its sole discretion. All shares of Class D
Preferred called for redemption which are not so converted will be redeemed.
Each holder of shares of Class D Preferred to be redeemed shall surrender the
certificate or certificates representing such shares to the Corporation at the
place designated in the Corporate Notice, and thereupon the applicable
redemption price for such shares as set forth in this Section 6 shall be paid to
the order of the person whose name appears on such certificate or certificates
and each surrendered certificate shall be canceled and retired. Holders of Class
D Preferred shall not have the right to require the Corporation to redeem their
shares of Class D Preferred.


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