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                                                                     EXHIBIT 4.3





                  CERTIFICATE OF DESIGNATIONS, PREFERENCES AND
             RELATIVE RIGHTS OF SERIES A CONVERTIBLE PREFERRED STOCK
                                       OF
                               BROADBANDNOW, INC.
                                December 16, 1999


                         Pursuant to Section 151 of the
                General Corporation Law of the State of Delaware

         BroadbandNOW, Inc. (the "CORPORATION"), a corporation organized and
existing under the General Corporation Law of the State of Delaware, does hereby
certify that, pursuant to authority conferred upon the Board of Directors of the
Corporation by ARTICLE III of its Certificate of Incorporation, as amended
(hereinafter referred to as the "CERTIFICATE OF INCORPORATION"), and pursuant to
the provisions of Section 151 of the General Corporation Law of the State of
Delaware, the Board of Directors, by unanimous written consent dated as of
December 16, 1999, duly approved and adopted the following resolution (the
"RESOLUTION"):

         RESOLVED, that, pursuant to the authority vested in the Board of
Directors of the Corporation by ARTICLE III of its Certificate of Incorporation,
the Board of Directors does hereby create, authorize and provide for the
issuance of Series A Preferred Stock, $0.001 par value, with a liquidation
preference of $18.80 per share, consisting of Six Million Nine Hundred Thousand
(6,900,000) shares, having the designations, preferences, relative,
participating, optional and other special rights and the qualifications,
limitations and restrictions thereof that are set forth in the Certificate of
Incorporation and in this Resolution as follows:

     1. NUMBER OF SHARES. The shares of the initial series of preferred stock
shall be designated "Series A Convertible Preferred Stock" (the "PREFERRED
STOCK"), and the number of shares of the Preferred Stock which may be issued
shall be Six Million Nine Hundred Thousand (6,900,000). The Board of Directors
may authorize the issuance of up to 4,893,617 shares of the 6,900,000 authorized
shares of the Preferred Stock (i) in consideration for cash payments to the
Corporation or (ii) upon consummation of the merger of BBNW Merger Sub, Inc., a
Texas corporation ("MERGER SUB"), with and into I 3S, Inc., a Texas corporation
("I 3S TEXAS") to the former I 3S Texas holders of shares of preferred stock
upon the conversion of such shares into shares of Preferred Stock or the right
to receive Preferred Stock pursuant to the terms of said merger. The remaining
2,006,383 shares of Preferred Stock may only be issued by the Corporation as
in-kind dividends on previously issued shares of the Preferred Stock in
accordance with SUBSECTION 2.1.1 below.


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     2. PREFERRED STOCK. The  designations,  preferences,  limitations,
relative rights and privileges in respect of the Preferred Stock are as follows:

         2.1 DIVIDENDS.

                  2.1.1 The holders of Preferred Stock shall be entitled to
receive semi-annual dividends, out of funds legally available therefor, at a
rate per share (the "DIVIDEND RATE") equal to the greater of (a) $1.504 per
annum per share (said dividend to be appropriately adjusted for stock divisions,
dividends, combinations, recapitalizations and reclassifications), or (b) if a
dividend (other than a dividend payable in shares of Common Stock) is declared
during such semi-annual period on the Common Stock (or any class thereof),
subject to the approval or consent of the holders of the Preferred Stock as
provided in SECTION 2.2 hereof, an amount per share equal to the aggregate
amount of dividends declared with respect to that number of shares of the Common
Stock into which the Preferred Stock then outstanding shall then be convertible
pursuant to SECTION 2.5 hereof, divided by the number of shares of the Preferred
Stock then outstanding. Such dividends shall be fully cumulative, prior and in
preference to any declaration or payment of any dividend or other distribution
on any other class or series of capital stock of the Corporation but shall be
payable only when, as and if declared by the Board of Directors of the
Corporation out of funds legally available for the payment of dividends.
Payments of dividends shall be made in arrears, at the election of the
Corporation, (i) in cash or (ii) in kind in the form of additional shares of
Preferred Stock, provided, however, that all accrued but unpaid dividends on the
Preferred Stock must be paid, in arrears, in cash, before payment of any cash
dividends on any other series or class of capital stock of the Corporation.

         Semi-annual dividend periods (each a "SEMI-ANNUAL DIVIDEND PERIOD")
shall commence on January 1 and July 1, in each year, except that the first
Semi-annual Dividend Period shall commence on the date of issuance of the
Preferred Stock, and shall end on and include the day immediately preceding the
first day of the next Semi-annual Dividend Period. Dividends on the shares of
Preferred Stock shall be payable on January 1 and July 1 of each year (a
"DIVIDEND PAYMENT DATE"), commencing July 1, 1999; provided, however, that no
obligation to pay a dividend shall exist until such dividends are declared by
the Board of Directors. Each such dividend shall be paid to the holders of
record of the Preferred Stock as they shall appear on the stock register of the
Corporation on such record date, not exceeding 45 days preceding such Dividend
Payment Date, as shall be fixed by the Board of Directors of the Corporation or
a duly authorized committee thereof.

         If, on any Dividend Payment Date, all accrued and unpaid dividends
provided for in this SECTION 2.1 are not paid to the holders of the Preferred
Stock (whether declared or undeclared), whether in cash or in additional shares
of Preferred Stock, then such dividends shall cumulate with additional dividends
thereon, compounded semi-annually, at the dividend rate applicable to the
Preferred Stock as provided in this SECTION 2.1, for each succeeding full
Semi-annual Dividend Period during which such dividends shall remain unpaid. In
the event the Corporation elects to pay dividends in additional shares of
Preferred Stock, the Corporation shall on the Dividend Payment Date deliver to
the holders certificates representing such shares.


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         Notwithstanding anything to the contrary in this Certificate of
Designation, in the event any conversion (including into Class A Common Stock),
redemption or liquidation occurs as of a date other than on a Dividend Payment
Date, the holder of Preferred Stock shall be paid, out of funds legally
available therefor, a pro rata dividend equal to the dividend payable for that
Semi-annual Dividend Period multiplied by a fraction, the numerator of which is
the number of days that have elapsed since the last Dividend Payment Date and
the denominator of which is the number of days in the Semi-annual Dividend
Period in which the conversion, redemption or liquidation occurs.

         If the Corporation elects to pay a dividend on the Preferred Stock in
kind in the form of additional shares of Preferred Stock, the Corporation shall
issue and deliver to each holder of the shares of Preferred Stock in lieu of,
and in full satisfaction of, any dividends not paid in cash, additional shares
of Preferred Stock with an aggregate Liquidation Preference equal to the
dividend not paid in cash, with any fractional share owing such holder of shares
of Preferred Stock to be held by the Corporation and paid in the form of a whole
share when any fractional shares owed to such holder of the shares of Preferred
Stock equal at least one whole share and any such fractional shares thereafter
to be held and accounted for by the Corporation in accordance with generally
accepted accounting principles until paid as a whole share or shares.

                  2.1.2 The amount of any dividends accrued on any share of the
Preferred Stock on any Dividend Payment Date shall be deemed to be the amount of
any unpaid dividends accumulated thereon to and including such Dividend Payment
Date, whether or not earned or declared. The amount of dividends accrued on any
share of the Preferred Stock on any date other than a Dividend Payment Date
shall be deemed to be the sum of (i) the amount of any unpaid dividends
accumulated thereon to and including the last preceding Dividend Payment Date,
whether or not earned or declared, and (ii) an amount determined by multiplying
(x) the Dividend Rate by (y) a fraction, the numerator of which shall be the
number of days from the last preceding Dividend Payment Date to and including
the date on which such calculation is made and the denominator of which shall be
the full number of days in such Semi-annual Dividend Period.

                  2.1.3 Immediately prior to authorizing or making any
distribution in redemption or liquidation with respect to the Preferred Stock
(other than a purchase or acquisition of Preferred Stock pursuant to a purchase
or exchange offer made on the same terms to holders of all outstanding Preferred
Stock), the Board of Directors shall, to the extent of any funds legally
available therefor, declare a dividend in cash on the Preferred Stock payable on
the distribution date in an amount equal to any accrued and unpaid dividends on
the Preferred Stock as of such date.

                  2.1.4 In the event there have been any accrued and unpaid
dividends on the Preferred Stock at the time of the consummation of an Approved
Offering, the Corporation shall first pay in cash all accrued and unpaid
dividends (together with any dividends calculated through the date of
consummation of the Approved Offering) on the Preferred Stock from the proceeds
from the Approved Offering.


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                  2.1.5 Except as provided under SUBSECTION 2.1.6 or SECTION
2.4, the Corporation shall not declare or pay any dividend or make any other
distribution on any shares of Parity Stock or Junior Stock (other than dividends
payable in Parity Stock or Junior Stock, as the case may be, to holders thereof)
or purchase, redeem or otherwise acquire for consideration any shares of Parity
Stock or Junior Stock, unless all aggregate accrued dividends on all outstanding
shares of Preferred Stock shall have been paid for all past periods.

                  2.1.6 If any dividends shall have been declared but not paid
in full or funds set apart for payment in full on the payment date for such
dividends on the outstanding shares of the Preferred Stock and any Parity Stock
that is equal in rank as to dividends, then, to the extent any dividends are
thereafter paid or set apart for payment on the outstanding shares of the
Preferred Stock or such Parity Stock, the money for such payment or so set aside
shall be shared ratably by the holders of the outstanding shares of the
Preferred Stock and the holders of the outstanding Parity Stock in proportion to
the respective unpaid dividends.

                  2.1.7 All accumulated and unpaid dividends on the Series A
Convertible Preferred Stock of I 3S Texas that, upon the merger of Merger Sub
with and into I 3S Texas, are to be cancelled and converted into the right to
receive an equal number of shares of Preferred Stock, shall be deemed to be
accumulated and unpaid dividends on such shares of Preferred Stock. Dividends on
each outstanding share of Preferred Stock shall accumulate from the date of
original issuance of the share of the preferred stock of I 3S Texas in exchange
for which such share of Preferred Stock is originally issued.

         2.2 VOTING RIGHTS.

                  2.2.1 The holders of Preferred Stock shall have no voting
rights whatsoever, except as set forth below in SUBSECTION 2.2.2 or as otherwise
existing under applicable law.

                  2.2.2 So long as any shares of Preferred Stock are
outstanding, the Corporation shall not, without first obtaining the approval (by
vote or written consent) of the holders of at least a majority of the shares of
Preferred Stock then outstanding, voting as a separate class, take any action
to:

                           2.2.2.1 approve an agreement or plan of merger or
consolidation or conversion under which the Corporation is to merge or
consolidate with or into any other corporation or convert into any other
business entity;

                           2.2.2.2 approve any sale or transfer of all or
substantially all of the assets of the Corporation;

                           2.2.2.3 create, authorize or issue any share of any
series or class of Prior Stock or Parity Stock, including the issuance of any
debt securities, stock or other security convertible into any class or series of
Prior Stock or Parity Stock;


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                           2.2.2.4 repurchase, redeem or retire any shares of
Preferred Stock or Parity Stock except pursuant to any provision of this
Certificate of Designation;

                           2.2.2.5 repurchase, redeem or retire any shares of
Common Stock or Junior Stock;

                           2.2.2.6 amend, alter or repeal any of the provisions
of the Certificate of Incorporation or this Certificate of Designation, if such
amendment, alteration or repeal would adversely affect any privilege,
preference, right or power of the Preferred Stock or the holders thereof;

                           2.2.2.7 increase or decrease the authorized number of
shares of Preferred Stock; or

                           2.2.2.8 authorize or pay any dividend or other
distribution (other than dividends payable to the holders of Preferred Stock as
contemplated by SUBSECTION 2.1.1 and dividends on the Class A Common Stock
payable in additional shares of Class A Common Stock) with respect to the
Preferred Stock or the Common Stock.

                  2.2.3 In addition to the special voting rights provided in
SUBSECTION 2.2.2 above, the holders of the Preferred Stock shall also have the
right to vote as a separate class on any matter if required by the General
Corporation Law of the State of Delaware or any successor statute.

        2.3 PREEMPTIVE RIGHTS. The holders of the Preferred Stock shall have the
preemptive right to subscribe for any and all issuances of (i) Common Stock or
other equity securities of the Corporation; (ii) options to purchase or rights
to subscribe for Common Stock or other equity securities of the Corporation;
(iii) securities convertible into or exchangeable for Common Stock or other
equity securities of the Corporation; and (iv) options to purchase or rights to
subscribe for such convertible or exchangeable securities; provided that, the
holders of the Preferred Stock shall not have a preemptive right to subscribe
for (i) Compensatory Securities (as adjusted to provide for any dividends, stock
distributions, splits, combinations or recapitalization), (ii) securities to be
issued in connection with a merger, an acquisition or an offering for property
interests (other than cash or new deferred payment obligations), (iii)
securities to be issued upon the conversion of previously outstanding
convertible securities, (iv) securities to be issued pursuant to SECTION 2.1 and
(v) securities to be issued in an Approved Offering, or where the preemptive
rights have been waived by a majority of the Preferred Stock then outstanding.
In the event the Corporation shall propose to issue any securities with respect
to which the holders of the Preferred Stock have the preemptive rights set forth
above, the Corporation shall first make an offering of Preferred Stock in
accordance with the following provisions.

                  2.3.1 The Corporation shall deliver a notice by certified mail
(the "PREEMPTION NOTICE") to the holders of Preferred Stock stating (i) its bona
fide intention to offer such shares or other securities, (ii) the number of such
shares or other securities to be offered, and (iii) the price and all material
terms, if any, upon which it proposes to offer such shares or


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other securities. Such notice shall be given at the addresses of the holders as
reflected in the Corporation's stock transfer records.

                  2.3.2 Within 20 calendar days after receipt of the Preemption
Notice, each holder of Preferred Stock may elect to purchase or obtain, at the
price and on the terms specified in the Preemption Notice, up to that portion of
such shares or other securities which equals the proportion that the number of
shares of Common Stock owned or issuable upon conversion and exercise of all
convertible and exercisable securities then held by such holder, including the
Preferred Stock, bears to the total number of shares of Common Stock then
outstanding (assuming full conversion and exercise of all convertible or
exercisable securities). The Corporation shall promptly, in writing, inform each
holder of Preferred Stock that purchases all the shares or other securities
available to it (each a "FULLY-EXERCISING HOLDER") of any other holder's failure
to do likewise.

                  2.3.3 The Corporation may, during the 90-day period following
the expiration of the period provided in SUBSECTION 2.3.2 above, offer the
remaining unsubscribed portion of the shares to any person or persons at a price
not less than, and upon terms no more favorable to the offeree than those
specified in the Preemption Notice. If the Corporation does not enter into an
agreement for the sale of the shares within such period, or if such agreement is
not consummated within 90 days of the execution thereof, the right provided
hereunder shall be deemed to be revived and such shares shall not be offered
unless first offered to the holders of Preferred Stock in accordance herewith.

         2.4 LIQUIDATION RIGHTS.

                  2.4.1 In the event of a Liquidation, the holders of Preferred
Stock shall be entitled to receive, out of the assets of the Corporation legally
available for distribution to stockholders and before any payment shall be made
or any assets distributed to the holders of Junior Stock, an amount per share
equal to the sum in cash of (i) $18.80 (the "LIQUIDATION PREFERENCE"), plus (ii)
on a per share basis, an amount equal to all dividends, if any, accumulated and
unpaid, whether or not declared or earned, as of the date of the final
distribution to the holders of the Preferred Stock. If the Corporation at any
time after the Issuance Date effects a subdivision of the outstanding Preferred
Stock, the Liquidation Preference for the Preferred Stock in effect immediately
before the subdivision shall be proportionately decreased, and conversely, if
the Corporation at any time after the Issuance Date effects a combination of the
Preferred Stock, the Liquidation Preference for the Preferred Stock in effect
immediately before the combination shall be proportionately increased. Any such
adjustment to the Liquidation Preference shall become effective at the time the
subdivision or combination becomes effective.

                  2.4.2 After payment to the holders of Preferred Stock of the
amounts set forth in SUBSECTION 2.4.1 above, the remaining assets of the
Corporation shall first be distributed to the holders of Class B Common Stock
and Class C Common Stock in accordance with ARTICLE III of the Certificate of
Incorporation, and then the holders of the Corporation's Common Stock shall be
entitled to share in all of the remaining assets and funds of the Corporation
ratably in proportion to the number of shares of Common Stock then outstanding.


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                  2.4.3 If, upon any Liquidation, the assets to be distributed
among the holders of Preferred Stock and any Parity Stock that is of equal rank
as to distributions of assets shall be insufficient to permit payment to such
holders of the full amounts to which they shall be entitled, the holders of
Preferred Stock and such Parity Stock shall share ratably in any such
distribution of assets in accordance with the percentage which would be payable
if all such amounts were paid in full.

                  2.4.4 The Corporation shall provide written notice to each
holder of Preferred Stock at least 20 days prior to any event of Liquidation or
a Change of Control.

                  2.4.5 By giving written notice to the Corporation prior to any
Liquidation or Change of Control, the holders of Preferred Stock may, at their
option, elect to forego their Liquidation Preference, and have their shares of
Preferred Stock converted into Class A Common Stock immediately prior to the
event of Liquidation or Change of Control pursuant to SUBSECTION 2.5.2 hereof.

                  2.4.6 Except with respect to holders that elect to convert
their shares of Preferred Stock into Class A Common Stock, for purposes of this
SECTION 2.4, the holders of a majority of the Preferred Stock may elect to have
treated as a Liquidation: (i) the consolidation or merger of the Corporation
with or into any other corporation or any other reorganization of the
Corporation, unless the stockholders of the Corporation immediately prior to any
such transaction are holders of a majority of the voting securities of the
surviving or acquiring corporation immediately thereafter (and for purposes of
this calculation equity securities which any stockholder or the Corporation
owned immediately prior to such merger or consolidation as a stockholder of
another party to the transaction shall be disregarded); or (ii) the sale or
other transfer in a single transaction or a series of related transactions of
all or substantially all of the assets of the Corporation.

         2.5 CONVERSION RIGHTS OF PREFERRED STOCK.

                  2.5.1 Automatic Conversion. Upon the occurrence of an Approved
Offering, each share of Preferred Stock shall immediately and automatically be
converted into such number of fully paid and nonassessable shares of Class A
Common Stock equal to the product of (A) the number of shares of Preferred Stock
held by such stockholder, multiplied by (B) the number determined by dividing
the then current Liquidation Preference by the then current Conversion Price.
The Corporation shall give not less than (i) ten (10) days prior written notice
to each holder of Preferred Stock of the estimated date of such Approved
Offering and (ii) three (3) days prior written notice of the actual date of the
Approved Offering. The Corporation and the holders of the Preferred Stock shall
carry out the exchange procedures set forth under SUBSECTION 2.5.3 as soon as
practicable on or after the consummation of the Approved Offering, it being
acknowledged by the Corporation that no holder shall be required to give the
notice otherwise required in SUBSECTION 2.5.2.

                  2.5.2 Optional Conversion. A holder of shares of Preferred
Stock may, at his option, at any time and from time to time, convert all or any
part of the shares of Preferred Stock beneficially owned by such holder into
such number of fully paid nonassessable shares of


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Class A Common Stock equal to the product of (A) the number of shares of
Preferred Stock held by such stockholder, multiplied by (B) the number
determined by dividing the then current Liquidation Preference by the then
current Conversion Price, by giving written notice to the Corporation and
delivering the certificates evidencing the Preferred Stock in accordance with
SUBSECTION 2.5.3 below. Such notice shall specify the date and place for the
consummation of the conversion (hereinafter such date, or the date of conversion
under SUBSECTION 2.5.1 above, or such other date as may be fixed by the mutual
agreement of the Corporation and such holder as the date for the particular
conversion, is referred to as the "CONVERSION DATE").

                  2.5.3 Exchange of Stock Certificates. Following a conversion
pursuant to SUBSECTION 2.5.1 or 2.5.2 above, each holder of shares of Preferred
Stock shall surrender such holder's certificates evidencing such shares, at the
principal office of the Corporation or at such other place as the Corporation
shall designate, and shall thereupon be entitled to receive certificates
evidencing the number of shares of Class A Common Stock into which such shares
of Preferred Stock have been converted. The Corporation, on the Conversion Date,
in exchange for the foregoing, will deliver to such holder or holders of the
Preferred Stock to be converted a certificate or certificates for the number of
shares of Class A Common Stock to which such holder shall be entitled as
aforesaid. Upon the Conversion Date, each holder of shares of Preferred Stock to
be converted into shares of Class A Common Stock shall be deemed to be the
holder of record of the Class A Common Stock issuable upon such conversion,
notwithstanding that the certificates representing such shares of Preferred
Stock shall not have been surrendered at the office of the Corporation, that
notice from the Corporation regarding the conversion shall not have been
received by any holder of shares of Preferred Stock, or that the certificates
evidencing such shares of Class A Common Stock shall not have been actually
delivered to such holder.

                  2.5.4 Dividends. No adjustment to the Conversion Price shall
be made for cash dividends declared but unpaid on any shares of the Preferred
Stock that shall be converted or for cash dividends on any Common Stock that
shall be issued upon such conversion, but all cash dividends declared and unpaid
on such shares of the Preferred Stock as of the Conversion Date shall constitute
a debt of the Corporation payable to the converting holder, and no cash dividend
shall be paid upon the Common Stock until such debt shall be paid or sufficient
funds set apart for the payment thereof.

                  2.5.5 Adjustments to Conversion Price.

                           2.5.5.1 Adjustment for Subdivisions and Combinations.
If the Corporation at any time or from time to time after the Issuance Date
effects a subdivision of the outstanding Class A Common Stock into a larger
number of shares, the Conversion Price for the Preferred Stock then in effect
immediately before that subdivision shall be proportionately decreased, and
conversely, if the Corporation at any time or from time to time after the
Issuance Date combines the outstanding shares of Class A Common Stock into a
smaller number of shares, the Conversion Price for the Preferred Stock then in
effect immediately before the combination shall be proportionately increased.
Any adjustment under this PARAGRAPH 2.5.5.1 shall become effective at the time
the subdivision or combination becomes effective.


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                           2.5.5.2 Adjustment for Certain Dividends and
Distributions. In the event the Corporation at any time or from time to time
after the Issuance Date declares or makes a dividend or other distribution with
respect to the Class A Common Stock payable in additional shares of Class A
Common Stock, then and in each such event the then current Conversion Price for
the Preferred Stock shall be decreased effective as of the date the additional
shares of Class A Common Stock are issued by multiplying the then current
Conversion Price for the Preferred Stock by a fraction (A) the numerator of
which is the total number of shares of Class A Common Stock issued and
outstanding immediately prior to the issuance of the additional shares of Class
A Common Stock and (B) the denominator of which is the total number of shares of
Class A Common Stock issued and outstanding immediately after the issuance of
the additional shares of Class A Common Stock.

                           2.5.5.3 Adjustment for Other Dividends and
Distributions. In the event the Corporation at any time or from time to time
after the Issuance Date declares or makes a dividend or other distribution with
respect to the Class A Common Stock payable in securities of the Corporation
other than additional shares of Class A Common Stock, then in each such event
provision shall be made so that the holders of Preferred Stock shall receive
upon conversion thereof, in addition to the number of shares of Class A Common
Stock receivable thereupon, the amount of securities of the Corporation that
they would have received had their Preferred Stock been converted into Class A
Common Stock prior to the effective date of the issuance of such other
securities.

                           2.5.5.4 Adjustment for Recapitalization,
Reclassification or Other Change. If the Class A Common Stock issuable upon the
conversion of the Preferred Stock is changed into the same or a different number
of shares of any other class or classes of stock, whether by recapitalization,
reclassification or other change (other than a subdivision or combination of
shares, a stock dividend or distribution, or a reorganization, provided for
elsewhere in this SUBSECTION 2.5.5) or into other securities or property, then
in each such event provision shall be made so that the holders of Preferred
Stock shall receive upon conversion thereof the kind and amount of stock and
other securities and property that they would have received had their Preferred
Stock been converted into Class A Common Stock immediately prior to such
recapitalization, reclassification or change, all subject to further adjustment
as provided herein.

                           2.5.5.5 Adjustment for Reorganizations. If at any
time or from time to time there is a capital reorganization of the Class A
Common Stock (other than a recapitalization, reclassification or other change
provided for elsewhere in this SUBSECTION 2.5.5), then in each such event,
provision shall be made so that the holders of Preferred Stock shall receive
upon conversion thereof, the kind and amount of stock and other securities and
property that they would have received had their Preferred Stock been converted
into Class A Common Stock immediately prior to such reorganization, all subject
to further adjustment as provided herein. In any such case, appropriate
adjustment shall be made in the application of the provisions of this SUBSECTION
2.5.5 with respect to the rights of holders of the Preferred Stock after the
reorganization to the end that the provisions of this SUBSECTION 2.5.5
(including adjustment of the Conversion Price for such Preferred Stock then in
effect and number of shares



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purchasable upon conversion of such Preferred Stock) shall be applicable after
that event and be as nearly equivalent to the provisions hereof as may be
practicable.

                           2.5.5.6 Minimum Adjustment. Except as hereinafter
provided, no adjustment of the Conversion Price hereunder shall be made if such
adjustment results in a change of the Conversion Price then in effect of less
than 0.1%. Any adjustment of less than 0.1% shall be carried forward and shall
be made at the time of and together with any subsequent adjustment which,
together with the adjustment or adjustments so carried forward, amounts to 0.1%
or more of the Conversion Price then in effect. However, upon conversion of the
Preferred Stock, the Corporation shall make all necessary adjustments not
theretofore made to the Conversion Price up to and including the date of such
conversion.

                  2.5.6 Notice of Adjustments. Whenever the Conversion Price or
the amount of Class A Common Stock or other securities deliverable upon the
conversion of the Preferred Stock shall be adjusted pursuant to the provisions
hereof, the Corporation shall forthwith file, at its principal executive office
and with any transfer agent or agents for its Preferred Stock and Class A Common
Stock, a statement, signed by an authorized officer of the Corporation, stating
the newly adjusted Conversion Price and adjusted amount of its Class A Common
Stock or other securities deliverable per share of the Preferred Stock
calculated to the nearest one one-hundredth and setting forth in reasonable
detail the method of calculation and the facts requiring such adjustment and
upon which such calculation is based and shall mail such certificate, by first
class mail, postage prepaid, to each registered holder of the Preferred Stock at
the holder's address as shown in the Corporation's books.

                  2.5.7 Reservation of Common Stock. The Corporation shall at
all times reserve and keep available out of its authorized but unissued Class A
Common Stock the full number of shares of Class A Common Stock deliverable upon
the conversion of all the then outstanding shares of Preferred Stock and shall
take all such action and obtain all such permits or orders as may be necessary
to enable the Corporation lawfully to issue such Class A Common Stock upon the
conversion of the Preferred Stock.

                  2.5.8 No Fractional Shares. No fractions of shares of Class A
Common Stock shall be issued upon conversion. If more than one share of
Preferred Stock shall be converted at any one time by the same holder, the
number of full shares of Class A Common Stock issuable upon conversion thereof
shall be computed on the basis of the aggregate number of shares of Preferred
Stock so surrendered. In lieu of any fractional shares that would otherwise be
issuable upon conversion of any shares of Preferred Stock, the Corporation shall
when, as and if funds are legally available therefor pay cash equal to such
fraction multiplied by the fair market value of a share of Class A Common Stock
as determined by the Board of Directors.

                  2.5.9 Consolidation, Mergers. In case of any consolidation or
merger of the Corporation with or into another corporation, or in case of any
sale or conveyance to another corporation of all or substantially all of the
assets of the Corporation, the holder of each share of the Preferred Stock then
outstanding shall have the right thereafter, so long as such holder's conversion
right hereunder shall exist, to convert such share of the Preferred Stock into
the kind and amount of shares of stock and other securities and property
receivable upon such


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consolidation, merger, sale or conveyance by the holder of the number of shares
of Class A Common Stock of the Corporation into which such share of the
Preferred Stock might have been converted immediately prior to such
consolidation, merger, sale or conveyance, and the Corporation shall cause
proper provision to be made in the Articles or Certificate of Incorporation of
the resulting or surviving corporation or otherwise to protect such conversion
right.

                  2.5.10 Payment of Taxes. The Corporation shall pay all issue
taxes, if any, incurred in connection with the issuance of its Class A Common
Stock or other securities or properties on conversion of any shares of the
Preferred Stock, but the Corporation shall not pay any transfer or other taxes
incurred by reason of the issuance of such Class A Common Stock or other
securities or properties in names other than those in which the share or shares
of the Preferred Stock surrendered for conversion may stand.


                  2.5.11 Adjustments to Remain Effective. Any adjustment of the
Conversion Price herein provided shall remain in effect until further adjustment
of the Conversion Price is required hereunder.

         2.6 REDEMPTION.

                  2.6.1 Mandatory Redemption at Election of Preferred Stock. The
Corporation shall be obligated to redeem and shall promptly redeem all of the
shares of Preferred Stock, upon written request by the holders of a majority of
the issued and outstanding shares of Preferred Stock after the occurrence of a
Triggering Event, for an amount per share equal to (i) the Liquidation
Preference, plus (ii) on a per share basis, an amount equal to all dividends, if
any, accumulated and unpaid, whether or not declared or earned (including any
dividends thereon calculated through the date of redemption) (the "MANDATORY
REDEMPTION OBLIGATION").

                  2.6.2 Failure to Make Payment. If and so long as the Mandatory
Redemption Obligation with respect to Preferred Stock shall not fully be
discharged, the Corporation shall not, directly or indirectly, declare or pay
any dividend or make any distributions on, or purchase, redeem or retire, or
satisfy any mandatory or optional redemption, sinking fund or other similar
obligation in respect of, any Parity Stock or Junior Stock or warrants, rights
or options exercisable for any such Parity Stock or Junior Stock (other than
dividends or distributions payable in a particular class or series of such
Parity Stock or Junior Stock, as the case may be, to holders thereof), except
that the Corporation may redeem Parity Stock that is also subject to mandatory
redemption provisions at such time on a pro rata basis with any required
redemption of the Series A Preferred Stock based on the relative required
redemption payment amounts.

         2.7 RIGHT OF FIRST REFUSAL. The Preferred Stock shall be "Required
Preferred Stock" for purposes of SUBSECTION 3.1.10 of the Corporation's
Certificate of Incorporation.


         2.8 CERTAIN DEFINITIONS. For purposes of this Certificate of
Designation, the following terms have the following meanings:


<PAGE>   12


          "APPROVED OFFERING" shall mean the consummation of the first
     underwritten public offering of Common Stock of the Corporation pursuant to
     a registration statement filed with the Securities and Exchange Commission
     under the Securities Act of 1933, as amended (or any successor provision),
     with a concurrent listing on the New York Stock Exchange, the American
     Stock Exchange, or the Nasdaq Stock Market, Inc. at an initial offering
     price of at least $20.00 per share (subject to adjustment for subsequent
     stock divisions, stock combinations and stock dividends with respect to the
     Common Stock) that results in gross proceeds to the Corporation (before
     deduction of underwriting discounts and expenses of sale) of not less than
     $30,000,000.

          "CHANGE OF CONTROL" shall mean the occurrence of any of the events
     described in Subsection 2.4.6.

          "COMPENSATORY SECURITIES" shall mean shares of Common Stock, rights,
     options or warrants granted or awarded by the Corporation, with the
     approval of its Board of Directors, to employees or directors of the
     Corporation as compensation for service to the Corporation in any such
     capacities, if such rights, options or warrants are granted at an exercise
     price or value not less than the fair market value of a share as of the
     date of grant and do not exceed an aggregate of 6,000,000 shares of Class A
     Common Stock (as adjusted to provide for any dividends, stock
     distributions, splits, combinations or recapitalizations).

          "COMMON STOCK" shall mean, collectively, the Class A Common Stock, the
     Class B Common Stock and the Class C Common Stock of the Corporation.

          "CONVERSION PRICE" shall mean the price at which shares of the Class A
     Common Stock shall be deliverable upon conversion of the Preferred Stock as
     adjusted from time to time as herein provided. The Conversion Price for the
     Preferred Stock shall initially be $18.80 per share.

          "ISSUANCE DATE" shall mean the actual initial date of issuance of the
     Preferred Stock.

          "JUNIOR STOCK" shall mean all Common Stock and all other shares of
     stock of any other class of the Corporation, whether or not presently
     authorized, ranking as to redemption, conversion, payment of dividends or
     distribution of assets junior to the Preferred Stock.

          "LIQUIDATION" shall mean any voluntary and involuntary liquidation,
     dissolution or winding up of the Corporation (including without limitation
     a liquidation or reorganization under Chapter 11 of the United States
     Bankruptcy Code, as amended and as may hereinafter be amended).

          "PARITY STOCK" shall mean all stock of the Corporation, whether or not
     presently authorized, ranking, as to redemption, conversion, payment of
     dividends or distribution of assets, on a parity with the Preferred Stock.


<PAGE>   13


          "PRIOR STOCK" shall mean all stock ranking, as to redemption,
     conversion, payment of dividends or distribution of assets, prior to the
     Preferred Stock.

          "STOCK PURCHASE AGREEMENTS" shall mean those certain Stock Purchase
     Agreements by and among I(3)S Funding I, L.L.C. ("FUNDING"), Blue Ridge
     Investors Limited Partnership ("BLUE RIDGE"), Spotswood Capital, LLC
     ("SPOTSWOOD"), the Corporation, James R. Price, Gary A. Dobbins, Clay C.
     Scott, Jr., Charles Bo Price and George Venner dated as of April 4, 1997,
     March 31, 1998 (as amended June 30, 1998), and December 30, 1998,
     respectively, whereby Funding purchased an aggregate of 4,979,777 shares of
     Class B Common Stock, and dated as of July 10, 1998 and December 30, 1998,
     respectively, whereby Blue Ridge and Spotswood each purchased 1,037,232
     shares of Class C Common Stock, all of which were further amended as of the
     Issuance Date.

          "TRIGGERING EVENT" shall mean the earlier to occur of (x) June 15,
     2004, (y) a Change of Control, or (z) the sale of a majority of the assets
     of the Corporation.

          2.9 PROHIBITION AGAINST REISSUANCE OF SHARES OF PREFERRED STOCK. Any
shares of Preferred Stock that are repurchased or otherwise acquired by the
Corporation or shares of Preferred Stock canceled upon conversion of the
Preferred Stock into shares of Class A Common Stock may not be reissued by the
Corporation."



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         IN WITNESS WHEREOF, and in accordance with Section 151 of the General
Corporation Law of the State of Delaware, the undersigned has executed this
Certificate of Designation as of the date first above written.

                                     BROADBANDNOW, INC.


                                     By:
                                         ---------------------------------------
                                           Name:
                                                 -------------------------------
                                           Title:
                                                  ------------------------------