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                                                                  Exhibit 10.25

                           FIRSTWORLD COMMUNICATIONS, INC.

                                STOCK OPTION AGREEMENT

     Capitalized terms used herein but not otherwise defined herein, shall have
the meanings assigned to such terms in that certain Employment Agreement, dated
as of October 1, 1998, by and between the Company (as defined below) and Sheldon
S. Ohringer (the "EMPLOYMENT AGREEMENT").

1.   NOTICE OF STOCK OPTION GRANT

     (a)  NOTICE:

     Sheldon S. Ohringer
     c/o FirstWorld Communications
     9333 Genesee Avenue, Suite 200
     San Diego, CA  92121

     The undersigned optionee ("OPTIONEE") has been granted an option to
purchase (the "STOCK OPTION") Series B Common Stock, par value $.0001 per share
(the "COMMON STOCK"), of FirstWorld Communications, Inc. (the "COMPANY"),
subject to the terms and conditions of this Stock Option Agreement, as follows. 

     Date of Grant:                     10/1/98

     Vesting Commencement Date:         10/1/98

     Exercise Price per Share:          $6.00 (as adjusted pursuant to Section
                                        2(c) below)

     Total Number of Shares Granted:    2,805,000 (as adjusted pursuant to
                                        Section 2(c) below)
     
     Total Exercise Price:              $16,830,000 (as adjusted pursuant to
                                        Section 2(c) below)
     
     Type of Option:                    Nonstatutory Stock Option

     Term/Expiration Date:              9/30/05

     (b)  VESTING SCHEDULE:

     This Stock Option shall be exercisable, in whole or in part, according to
the following vesting schedule:
     
          (i)   with respect to one-third (1/3) of the Shares purchasable
     thereunder, on the Commencement Date (as defined in the Employment
     Agreement);

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          (ii)  with respect to one-third (1/3) of the Shares purchasable
     thereunder, on the first anniversary of the Commencement Date; and
          
          (iii) with respect to the remaining one-third (1/3) of the Shares
     purchasable thereunder, on the second anniversary of the Commencement Date;
          
PROVIDED, HOWEVER, that immediately prior to the effectiveness of a Change of
Control (as defined below) of the Company, all of the Shares subject to the
Stock Option shall immediately vest; and FURTHER PROVIDED, HOWEVER, if the
Company has a market capitalization of at least $1.2 billion (as adjusted as
described below) for a period of twenty (20) consecutive trading days at any
time during a three year period beginning on October 1, 1998 and ending on
September 30, 2001, then all of the Shares subject to the Stock Option shall
immediately vest.
     
     For the purposes hereof, a "Change in Control" of the Company means the
occurrence of one of the following events:

          (1)  the sale, lease, transfer, conveyance or other disposition, in
     one or a series of related transactions, of all or substantially all of the
     assets of the Company and its subsidiaries, taken as a whole, to any person
     (as such term is defined in Section 3(a)(9) of the Securities Exchange Act
     of 1934, as amended (the "EXCHANGE ACT")) or group (as such term is defined
     in Section 13(d)(3) of the Exchange Act and Section 14(d)(2) of the
     Exchange Act);

          (2)  the adoption of a plan relating to the liquidation or dissolution
     of the Company; or

          (3)  any person (as defined above) or group (as defined above) other
     than the Permitted Holders (as defined below) is or becomes the Beneficial
     Owner (as defined below), directly or indirectly, of 50% or more of the
     total voting stock or total common equity of the Company, including by way
     of merger, consolidation or otherwise.

     For the purposes hereof, the term "Permitted Holders" means (a) Donald L.
Sturm, Colorado Spectra 1, LLC, a Colorado limited liability company ("SPECTRA
1"), Colorado Spectra 2, LLC, a Colorado limited liability company ("SPECTRA
2"), Colorado Spectra 3, LLC, a Colorado limited liability company ("SPECTRA
3"), Enron Capital & Trade Resources Corp., a Delaware corporation ("ENRON"),
and any other person which any of the foregoing entities directly or indirectly
controls, or is under common control with, or is controlled by (other than the
Company and its subsidiaries) and (b) any child, stepchild, spouse, sibling,
son-in-law, daughter-in-law, brother-in-law or sister-in-law (including adoptive
relationships) of Donald L. Sturm (or any entity all of the beneficial ownership
interests of which are owned by such a relative) to whom membership interests in
Spectra 1, Spectra 2 or Spectra 3 are distributed to upon the death of Donald L.
Sturm.  The term "Beneficial Owner" means a beneficial owner as defined in Rules
13d-3 and 13d-5 under the Exchange Act (or any successor rules), including (but
not limited to) the provisions of such rules that a person shall be deemed to
have beneficial ownership of all securities that such person has a right to
acquire within 60 days; PROVIDED that a person will not be deemed a beneficial
owner of, or to own beneficially, any securities if such beneficial ownership
(1) arises solely as a result of a revocable proxy delivered in response to a
proxy or consent

                                       2

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solicitation made pursuant to, and in accordance with, the Exchange Act and 
(2) is not also then reportable on Schedule 13D or Schedule 13G (or any 
successor schedule) under the Exchange Act.  The term "controls," as used 
with respect to any person, means the possession, directly or indirectly, of 
the power to direct or cause the direction of the management or policies of 
such person, whether through the ownership of voting securities or voting 
interests or otherwise.
     
     For the purposes hereof, market capitalization of $1.2 billion assumes
60,000,000 fully diluted shares of Common Stock (regardless of whether
60,000,000 shares of Common Stock are actually trading as of any period of
determination) and a market price of $20.00 per share (subject to adjustment as
described in the following sentence).  If the number of fully diluted shares of
Common Stock is greater than or less than 60,000,000 shares of Common Stock, the
target market capitalization shall be proportionately adjusted; PROVIDED THAT
the $20.00 per share market price would not be so adjusted, except to the extent
required to appropriately reflect any subdivision (by any stock split, stock
dividend, recapitalization or otherwise), combination (by reverse stock split or
otherwise) or other adjustment in the number of outstanding shares of the
Company as determined on a fully diluted basis made without the receipt of
consideration to the Company after October 1, 1998.
     
     (c)  TERMINATION PERIOD:

     Optionee acknowledges that he (or his estate) will have ninety (90) days
from the Date of Termination (as defined in the Employment Agreement) to
exercise all Shares of Common Stock vested under the Stock Option as of the Date
of Termination.  In no event may Optionee exercise this Option after the
"Term/Expiration Date" set forth in Section 1(a) above.
     
2.   AGREEMENT

          (a)  GRANT OF OPTION.  The Board of Directors of the Company (the
     "BOARD") hereby grants to the Optionee the Stock Option to purchase the
     number of Shares set forth in the Notice of Grant, at the exercise price
     per share set forth in the Notice of Grant (the "EXERCISE PRICE"), and
     subject to the terms and conditions hereof.
     
          This Stock Option is not intended to qualify as an Incentive Stock
     Option as defined in Section 422 of the Code; therefore, this Stock Option
     shall be treated as a Nonstatutory Stock Option ("NSO").

          (b)  EXERCISE OF OPTION.

               (1)  RIGHT TO EXERCISE.  This Stock Option is exercisable during
          its term in accordance with the vesting schedule set out in the Notice
          of Grant and the applicable provisions of this Stock Option Agreement.
     
               (2)  METHOD OF EXERCISE.  This Stock Option is exercisable by
          delivery of an exercise notice, in the form attached as EXHIBIT A (the
          "EXERCISE NOTICE"), which shall state the election to exercise the
          Stock Option, the number of Shares with respect to which the Stock
          Option is being exercised, and such other representations and
          agreements as may be required by the Company. The Exercise

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          Notice shall be accompanied by payment of the aggregate Exercise Price
          as to all Shares being exercised thereby.  This Stock Option shall be 
          deemed to be exercised upon receipt by the Company of such fully 
          executed Exercise Notice accompanied by the aggregate Exercise Price.
     
               No Shares shall be issued pursuant to the exercise of a Stock
          Option unless such issuance and such exercise complies with applicable
          laws. Assuming such compliance, for income tax purposes the Shares
          shall be considered transferred to the Optionee on the date on which
          the Stock Option is exercised with respect to such Shares.

          (c)  ADJUSTMENT TO EXERCISE PRICE AND NUMBER OF SHARES.  In order to
     prevent dilution of the rights granted to Optionee under the Stock Option,
     the number of shares of Common Stock subject to the Stock Option and the
     Exercise Price of such Common Stock shall be subject to adjustment from
     time to time as provided in this Section 2(c).

               (1)  SUBDIVISION OR COMBINATION OF STOCK.

                    (A)  If at any time or from time to time after the
               Commencement Date the Company shall subdivide (by stock split,
               stock dividend or otherwise) its outstanding shares of common
               stock, the Exercise Price in effect immediately prior to such
               subdivision shall, concurrently with the effectiveness of such
               subdivision, be proportionately decreased.  In the event the
               outstanding shares of common stock shall be combined or
               consolidated, by reclassification or otherwise, into a lesser
               number of shares of common stock, the Exercise Price then in
               effect shall, concurrently with the effectiveness of such
               combination or consolidation, be proportionately increased.

                    (B)  Upon each adjustment of the Exercise Price as provided
               in Section 2(c)(1)(A), Optionee thereafter shall be entitled to
               purchase, at the Exercise Price resulting from such adjustment,
               the number of shares of Common Stock (calculated to the nearest
               whole share) obtained by multiplying the Exercise Price in effect
               immediately prior to such adjustment by the number of shares
               purchasable pursuant hereto immediately prior to such adjustment
               and dividing the product thereof by the Exercise Price resulting
               from such adjustment.

               (2)  OTHER DISTRIBUTIONS.

                    (A)  In case the Company shall after the Commencement Date
               distribute to the holders of its common stock evidences of its
               indebtedness or assets (excluding regular cash dividends or
               distributions and dividends or distributions referred to in
               Section 2(c)(1) above) in connection with a split-up, spin-off or
               otherwise, then in each such case the Exercise Price in effect
               thereafter shall be determined by multiplying the Exercise Price
               in 

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               effect immediately prior thereto by a fraction, the numerator
               of which shall be the total number of shares of common stock
               outstanding multiplied by the Fair Market Value (as defined in
               Section 2(c)(5) below) per share of common stock prior to such
               distribution, less the fair market value (as determined by the
               Board) of said assets or evidences of indebtedness so
               distributed, and the denominator of which shall be the total
               number of shares of common stock outstanding multiplied by the
               Fair Market Value per share of common stock prior to the
               distribution.  Such adjustment shall be made successively
               whenever such a record date is fixed.  Such adjustment shall be
               made whenever any such distribution is made and shall become
               effective immediately after the record date for the determination
               of stockholders entitled to receive such distribution.

                    (B)  Upon each adjustment of the Exercise Price as provided
               in Section 2(c)(2)(A), Optionee thereafter shall be entitled to
               purchase, at the Exercise Price resulting from such adjustment,
               the number of shares of Common Stock (calculated to the nearest
               whole share) obtained by multiplying the Exercise Price in effect
               immediately prior to such adjustment by the number of shares
               purchasable pursuant hereto immediately prior to such adjustment
               and dividing the product thereof by the Exercise Price resulting
               from such adjustment.

               (3)  No adjustment in the Exercise Price and/or the number of
          shares subject to the Stock Option shall be made if such adjustment
          would result in a change in (i) the Exercise Price of less than one
          cent ($0.01) per share or (ii) the number of shares represented by the
          Stock Option of less than one share (the "ADJUSTMENT THRESHOLD
          AMOUNT").  Any adjustment not made because the Adjustment Threshold
          Amount is not satisfied shall be carried forward and made, together
          with any subsequent adjustments, at the earlier of such time as (a)
          the aggregate amount of all such adjustments is at least equal to the
          Adjustment Threshold Amount or (b) the shares of Common Stock subject
          to the Stock Option are acquired.

               (4)  Upon the occurrence of each adjustment or readjustment of
          the Exercise Price pursuant to this Section 2(c), the Company promptly
          shall compute such adjustment or readjustment in accordance with the
          terms hereof and prepare and furnish to Optionee a certificate setting
          forth such adjustment or readjustment, showing in detail the facts
          upon which such adjustment or readjustment is based.

               (5)  "Fair Market Value" of a share of common stock as of a given
          date shall be: (i) the average closing sale price of a share of common
          stock on the principal exchange on which the common stock is then
          trading, if any, over the last ten trading days prior to such date,
          or, if shares were not traded during such period, over the next
          preceding ten trading day period during which a sale occurred; (ii) if
          the common stock is not traded on an exchange but is quoted on Nasdaq
          or a successor quotation system, (1) the average closing sale price
          over the last ten trading days (if the common stock is then quoted on
          the Nasdaq National Market or the Nasdaq SmallCap 

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          Market) or (2) the mean between the closing representative bid and 
          asked prices (in all other cases) for a share of the common stock over
          the last ten trading days prior to such date, or, if shares were not 
          traded during such period, then over the next preceding ten trading 
          day period during which a sale occurred, as reported by Nasdaq or such
          successor quotation system; (iii) if the common stock is not publicly 
          traded on an exchange and not quoted on Nasdaq or a successor 
          quotation system, the mean between the closing bid and asked prices 
          for a share of common stock over the last ten trading days prior to 
          such date, or, if shares were not traded during such period, then over
          the next preceding ten trading day period during which a sale 
          occurred, as determined in good faith by the Board; or (iv) if the 
          common stock is not publicly traded, the fair market value of a share 
          of common stock established by the Board acting in good faith.

               (6)  Prior to the consummation of any recapitalization,
          reorganization, reclassification, consolidation, merger or other
          transaction which is effected in such a way that holders of common
          stock are entitled to receive (either directly or upon subsequent
          liquidation) stock, securities or assets with respect to or in
          exchange for such securities (each an "ORGANIC CHANGE"), the Company
          shall make appropriate provision to ensure that Optionee shall have
          the right to acquire and receive upon Optionee's acquisition of the
          shares of Common Stock subject to the Stock Option subsequent to such
          consummation, in lieu of or in addition to (as the case may be) the
          shares of Common Stock subject to the Stock Option, such shares of
          stock, securities or assets as Optionee would be entitled to receive
          if the shares of Common Stock subject to the Stock Option had been
          acquired immediately prior to such Organic Change.  In any such case,
          the Company shall make appropriate provision with respect to
          Optionee's rights and interests to insure that the provisions of this
          Section 2(c) shall thereafter be applicable to the Stock Option.  The
          Company shall not effect any such Organic Change unless, prior to the
          consummation thereof, the successor entity (if other than the Company)
          resulting from such Organic Change (including a purchaser of all or
          substantially all of the Company's assets) assumes by written
          instrument the obligation to deliver to Optionee such shares of stock,
          securities or assets as, in accordance with the foregoing provisions,
          Optionee may be entitled to acquire upon acquisition of the shares of
          Common Stock subject to the Stock Option.

          (d)  LOCK-UP PERIOD.  Optionee hereby agrees that, if so requested by
     the Company or any representative of the underwriters (the "MANAGING
     UNDERWRITER") in connection with any registration of the offering of any
     securities of the Company under the Securities Act, Optionee shall not sell
     or otherwise transfer any Shares or other securities of the Company during
     the 180-day period (or such other period as may be requested in writing by
     the Managing Underwriter and agreed to in writing by the Company) (the
     "MARKET STANDOFF PERIOD") following the effective date of the registration
     statement of the Company filed under the Securities Act.  Such restriction
     shall apply only to the first registration statement of the Company to
     become effective under the Securities Act that includes securities to be
     sold on behalf of the Company to the public in an underwritten public
     offering under the Securities Act.  The Company may impose stop-transfer
     instructions with respect to securities subject to the foregoing
     restrictions until the end of such Market Standoff Period.

                                       6

<PAGE>

          (e)  METHOD OF PAYMENT.  Payment of the aggregate Exercise Price shall
     be by any of the following, or a combination thereof, at the election of
     the Optionee:

               (1)  cash or check;

               (2)  consideration received by the Company under a formal
          cashless exercise program adopted by the Company; or

               (3)  surrender of other Shares which, (i) in the case of Shares
          acquired upon exercise of an option, have been owned by the Optionee
          for more than six (6) months on the date of surrender and (ii) have a
          Fair Market Value (as defined in Section 2(c)(5) above) on the date of
          surrender equal to the aggregate Exercise Price of the Shares being
          exercised thereby.

          (f)  RESTRICTIONS ON EXERCISE.

               (1)  This Stock Option may not be exercised if the issuance of
          such Shares upon such exercise or the method of payment of
          consideration for such Shares would constitute a violation of any
          Applicable Law (as defined below).

               For the purposes hereof, "Applicable Laws" means the requirements
          relating to the administration of stock option plans under U.S. state
          corporate laws, U.S. federal and state securities laws, the Internal
          Revenue Code of 1986, as amended, and any stock exchange or quotation
          system on which the Common Stock is listed or quoted.

               (2)  Upon any exercise of the Stock Option, Optionee agrees that
          he will hold at least 40% of the shares acquired pursuant to such
          Stock Option exercise for at least one year from the date of such
          Stock Option exercise; PROVIDED, HOWEVER, that the foregoing
          requirement will not apply from and after (i) a Change in Control (as
          defined above) of the Company or (ii) a merger, consolidation or other
          transaction in which the Company is not the surviving entity and in
          which all of the Company's stockholders receive cash or other
          consideration for their shares as a result of such merger,
          consolidation or other transaction.  In addition, in connection with a
          merger, consolidation or other transaction in which the Company is not
          the surviving entity and in which all of the Company's stockholders
          receive stock for their shares as a result of such merger,
          consolidation or other transaction, the period during which Optionee
          held the restricted shares of the Company will be added to the time
          Optionee holds the shares acquired in connection with such merger,
          consolidation or other transaction for purposes of determining the one
          year holding period for the restricted shares.

               In connection with all Stock Option exercises, certificates
          representing an aggregate of 40% of the shares acquired pursuant to
          such exercise shall be endorsed conspicuously as follows:

                                       7

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               "BY THE TERMS OF AN EMPLOYMENT AGREEMENT, CERTAIN RESTRICTIONS
          HAVE BEEN PLACED ON THE TRANSFER OF THE SECURITIES REPRESENTED BY THIS
          CERTIFICATE.  THE CORPORATION WILL FURNISH A COPY OF SUCH AGREEMENT TO
          THE HOLDER OF THIS CERTIFICATE WITHOUT CHARGE UPON REQUEST TO THE
          CORPORATION AT ITS PRINCIPAL PLACE OF BUSINESS OR REGISTERED OFFICE."

               In addition, the Company will be entitled to issue "stop-
          transfer" orders to its transfer agent (the "TRANSFER AGENT") with
          respect to the Common Stock that bears the endorsement set forth
          above.  At the conclusion of each applicable one-year period, the
          Company will cause the Transfer Agent to remove the above legend from
          the shares bearing such legend and which were restricted from transfer
          during the prior one-year period pursuant to this Section 2(f)(2).

          (g)  NON-TRANSFERABILITY OF OPTION.  This Stock Option may not be
     transferred in any manner otherwise than by will or by the laws of descent
     or distribution and may be exercised during the lifetime of Optionee only
     by Optionee.  The terms of this Stock Option Agreement shall be binding
     upon the executors, administrators, heirs, successors and assigns of the
     Optionee.
          
          (h)  TERM OF OPTION.  This Stock Option may be exercised only within
     the term set out in the Notice of Grant, and may be exercised during such
     term only in accordance with the terms of this Stock Option.
          
          (i)  TAX CONSEQUENCES.  Set forth below is a brief summary as of the
     date of this Stock Option of some of the federal tax consequences of
     exercise of this Stock Option and disposition of the Shares.  THIS SUMMARY
     IS NECESSARILY INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO
     CHANGE.  THE OPTIONEE SHOULD CONSULT A TAX ADVISER BEFORE EXERCISING THIS
     STOCK OPTION OR DISPOSING OF THE SHARES.  
     
               (1)  EXERCISE OF NONSTATUTORY STOCK OPTION.  There may be a
          regular federal income tax liability upon the exercise of a
          Nonstatutory Stock Option.  The Optionee will be treated as having
          received compensation income (taxable at ordinary income tax rates)
          equal to the excess, if any, of the Fair Market Value of the Shares on
          the date of exercise over the Exercise Price.  If Optionee is an
          employee or a former employee, the Company will be required to
          withhold from Optionee's compensation or collect from Optionee and pay
          to the applicable taxing authorities an amount in cash equal to a
          percentage of this compensation income at the time of exercise, and
          may refuse to honor the exercise and refuse to deliver Shares if such
          withholding amounts are not delivered at the time of exercise. 
     
               (2)  DISPOSITION OF SHARES.  In the case of an NSO, if Shares are
          held for at least one year, any gain realized on disposition of the
          Shares will be treated as long-term capital gain for federal income
          tax purposes.  

                                       8

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          (j)  ENTIRE AGREEMENT; GOVERNING LAW.  The Employment Agreement and
     this Stock Option Agreement constitute the entire agreement of the parties
     with respect to the subject matter hereof and supersede in their entirety
     all prior undertakings and agreements of the Company and Optionee with
     respect to the subject matter hereof, and may not be modified adversely to
     the Optionee's interest except by means of a writing signed by the Company
     and Optionee.  This agreement is governed by the internal substantive laws,
     but not the choice of law rules, of California.  
          
          (k)  NO GUARANTEE OF CONTINUED EMPLOYMENT.  OPTIONEE ACKNOWLEDGES AND
     AGREES THAT THE VESTING OF SHARES PURSUANT TO THE VESTING SCHEDULE HEREOF
     IS NOT EARNED THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS STOCK
     OPTION OR ACQUIRING SHARES HEREUNDER.  OPTIONEE FURTHER ACKNOWLEDGES AND
     AGREES THAT THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE
     VESTING SCHEDULE SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED
     PROMISE OF CONTINUED ENGAGEMENT AS AN EMPLOYEE OF THE COMPANY.

     Optionee has reviewed this Stock Option in its entirety, has had an
opportunity to obtain the advice of counsel prior to executing this Stock Option
Agreement and fully understands all provisions of the Stock Option.  Optionee
hereby agrees to accept as binding, conclusive and 
final all decisions or interpretations of the Board upon any questions arising
under this Stock Option.  Optionee further agrees to notify the Company upon any
change in the residence address indicated below.  


OPTIONEE:                                    FIRSTWORLD COMMUNICATIONS, INC.,
                                             a Delaware corporation

/s/ Sheldon S. Ohringer                      /s/ David Gandini
----------------------------------           -----------------------------------
SHELDON S. OHRINGER                          Name: David Gandini
                                             Title: Executive Vice President


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

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

----------------------------------
Residence Address

Date:   October 1, 1998

                                       9

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                                      EXHIBIT A

                                   EXERCISE NOTICE

FirstWorld Communications
9333 Genesee Avenue, Suite 200
San Diego, California  92121

Attention:  Chief Financial Officer

1)   EXERCISE OF OPTION.  Effective as of today, ____________ ___, _____, the
     undersigned ("OPTIONEE") hereby elects to exercise Optionee's option to
     purchase (the "OPTION") ___________ shares of the Series B Common Stock,
     par value $.0001 per share (the "SHARES"), of FirstWorld Communications,
     Inc., a Delaware corporation (the "COMPANY"), under and pursuant to the
     Stock Option Agreement dated October 1, 1998 (the "OPTION AGREEMENT").

2)   DELIVERY OF PAYMENT.  Optionee herewith delivers to the Company the full
     purchase price of the Shares, as set forth in the Option Agreement.

3)   REPRESENTATIONS OF OPTIONEE.  Optionee acknowledges that Optionee has
     received, read and understood the Option Agreement and agrees to abide by
     and be bound by its terms and conditions.

4)   RIGHTS AS STOCKHOLDER.  Until the issuance of the Shares (as evidenced by
     the appropriate entry on the books of the Company or of a duly authorized
     transfer agent of the Company), no right to vote or receive dividends or
     any other rights as a stockholder shall exist with respect to the Shares
     acquired hereby, notwithstanding the exercise of the Option.  The Shares
     shall be issued to the Optionee as soon as practicable after the Option is
     exercised.

5)   COMPANY'S RIGHT OF FIRST REFUSAL.  Before any Shares held by Optionee or
     any transferee (either being sometimes referred to herein as the "HOLDER")
     may be sold or otherwise transferred (including transfer by gift or
     operation of law), the Company or its assignee(s) shall have a right of
     first refusal to purchase the Shares on the terms and conditions set forth
     in this Section (the "RIGHT OF FIRST REFUSAL").

     a)   NOTICE OF PROPOSED TRANSFER.  The Holder of the Shares shall deliver
          to the Company a written notice (the "NOTICE") stating:  (i) the
          Holder's bona fide intention to sell or otherwise transfer such
          Shares; (ii) the name of each proposed purchaser or other transferee
          ("PROPOSED TRANSFEREE"); (iii) the number of Shares to be transferred
          to each Proposed Transferee; and (iv) the bona fide cash price or
          other consideration for which the Holder proposes to transfer the
          Shares (the "OFFERED PRICE"), and the Holder shall offer the Shares at
          the Offered Price to the Company or its assignee(s).

                                      A-1

<PAGE>

     b)   EXERCISE OF RIGHT OF FIRST REFUSAL.  At any time within thirty (30)
          days after receipt of the Notice, the Company and/or its assignee(s)
          may, by giving written notice to the Holder, elect to purchase all,
          but not less than all, of the Shares proposed to be transferred to any
          one or more of the Proposed Transferees, at the purchase price
          determined in accordance with subsection (c) below.

     c)   PURCHASE PRICE.  The purchase price ("PURCHASE PRICE") for the Shares
          purchased by the Company or its assignee(s) under this Section shall
          be the Offered Price.  If the Offered Price includes consideration
          other than cash, the cash equivalent value of the non-cash
          consideration shall be determined by the Board of Directors of the
          Company (the "BOARD") in good faith.

     d)   PAYMENT.  Payment of the Purchase Price shall be made, at the option
          of the Company or its assignee(s), in cash (by check), by cancellation
          of all or a portion of any outstanding indebtedness of the Holder to
          the Company (or, in the case of repurchase by an assignee, to the
          assignee), or by any combination thereof within 30 days after receipt
          of the Notice or in the manner and at the times set forth in the
          Notice.

     e)   HOLDER'S RIGHT TO TRANSFER.  If all of the Shares proposed in the
          Notice to be transferred to a given Proposed Transferee are not
          purchased by the Company and/or its assignee(s) as provided in this
          Section, then the Holder may sell or otherwise transfer such Shares to
          that Proposed Transferee at the Offered Price or at a higher price,
          PROVIDED that such sale or other transfer is consummated within 60
          days after the date of the Notice, that any such sale or other
          transfer is effected in accordance with any applicable securities laws
          and that the Proposed Transferee agrees in writing that the provisions
          of this Section shall continue to apply to the Shares in the hands of
          such Proposed Transferee.  If the Shares described in the Notice are
          not transferred to the Proposed Transferee within such period, a new
          Notice shall be given to the Company, and the Company and/or its
          assignees shall again be offered the Right of First Refusal before any
          Shares held by the Holder may be sold or otherwise transferred.

     f)   EXCEPTION FOR CERTAIN FAMILY TRANSFERS.  Anything to the contrary
          contained in this Section notwithstanding, the transfer of any or all
          of the Shares during the Optionee's lifetime or on the Optionee's
          death by will or intestacy to the Optionee's immediate family or a
          trust for the benefit of the Optionee's immediate family shall be
          exempt from the provisions of this Section.  "Immediate Family" as
          used herein shall mean spouse, lineal descendant or antecedent,
          father, mother, brother or sister.  In such case, the transferee or
          other recipient shall receive and hold the Shares so transferred
          subject to the provisions of this Section, and there shall be no
          further transfer of such Shares except in accordance with the terms of
          this Section.

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<PAGE>

     g)   TERMINATION OF RIGHT OF FIRST REFUSAL.  The Company's Right of First
          Refusal shall terminate immediately as to all Shares upon the
          occurrence of the first to occur of the following events:

          i)   The acquisition of the Company by another entity by means of the
               merger or consolidation of the Company with or into another
               corporation in which the stockholders of the Company own less
               than 50% of the voting securities of the surviving entity;

          ii)  The sale of all or substantially all of the assets of the
               Company; or

          iii) The date of the first sale of Common Stock of the Company to the
               general public pursuant to a registration statement filed with
               and declared effective by the Securities and Exchange Commission
               under the Securities Act of 1933, as amended.

6)   TAX CONSULTATION.  Optionee understands that Optionee may suffer adverse
     tax consequences as a result of Optionee's purchase or disposition of the
     Shares.  Optionee represents that Optionee has consulted with any tax
     consultants Optionee deems advisable in connection with the purchase or
     disposition of the Shares and that Optionee is not relying on the Company
     for any tax advice.

7)   RESTRICTIVE LEGENDS AND STOP-TRANSFER ORDERS.

     a)   LEGENDS.  Optionee understands and agrees that the Company shall cause
          the legends set forth below or legends substantially equivalent
          thereto, to be placed upon any certificate(s) evidencing ownership of
          the Shares together with any other legends that may be required by the
          Company or by state or federal securities laws:

          THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
          RESTRICTIONS ON TRANSFER AND A RIGHT OF FIRST REFUSAL HELD BY THE
          ISSUER OR ITS ASSIGNEE(S) AS SET FORTH IN THE EXERCISE NOTICE
          BETWEEN THE ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A
          COPY OF WHICH MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF THE
          ISSUER.  SUCH TRANSFER RESTRICTIONS AND RIGHT OF FIRST REFUSAL
          ARE BINDING ON TRANSFEREES OF THESE SHARES.

     b)   REFUSAL TO TRANSFER.  The Company shall not be required (i) to
          transfer on its books any Shares that have been sold or otherwise
          transferred in violation of any of the provisions of this Agreement or
          (ii) to treat as owner of such Shares or to accord the right to vote
          or pay dividends to any purchaser or other transferee to whom such
          Shares shall have been so transferred.

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<PAGE>

8)   SUCCESSORS AND ASSIGNS.  The Company may assign any of its rights under
     this Agreement to single or multiple assignees, and this Agreement shall
     inure to the benefit of the successors and assigns of the Company.  Subject
     to the restrictions on transfer herein set forth, this Agreement shall be
     binding upon Optionee and his or her heirs, executors, administrators,
     successors and assigns.

9)   INTERPRETATION.  Any dispute regarding the interpretation of this Agreement
     shall be submitted by Optionee or by the Company forthwith to the Board (or
     a committee thereof) which shall review such dispute at its next regular
     meeting.  The resolution of such a dispute by the Board (or a committee
     thereof) shall be final and binding on all parties.

10)  GOVERNING LAW.  This Agreement is governed by the internal substantive
     laws, but not the choice of law rules, of California.

11)  ENTIRE AGREEMENT.  The Employment Agreement and the Option Agreement are
     incorporated herein by reference.  This Agreement, the Employment Agreement
     and the Option Agreement constitute the entire agreement of the parties
     with respect to the subject matter hereof and supersede in their entirety
     all prior undertakings and agreements of the Company and Optionee with
     respect to the subject matter hereof, and may not be modified adversely to
     the Optionee's interest except by means of a writing signed by the Company
     and Optionee.


Submitted by:                                Accepted by:

OPTIONEE:                                    FIRSTWORLD COMMUNICATIONS, INC.
                                             a Delaware corporation


SHELDON S. OHRINGER
                                             -----------------------------------
----------------------------------           Name:
Signature                                         ------------------------------
                                             Title:
                                                   -----------------------------
                                             Address:
Address:
                                             9333 Genesee Avenue, Suite 200
----------------------------------           San Diego, California  92121

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

                                             -----------------------------------
                                             Date Received




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