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                                                                     Exhibit 4.1



                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                            NEON COMMUNICATIONS, INC.



FIRST: The name of the Corporation is: NEON Communications, Inc.

SECOND: The address of its registered office in the State of Delaware is
Corporation Trust Center, 1209 Orange Street, in the City of Wilmington, County
of New Castle. The name of its registered agent at such address is The
Corporation Trust Company.

THIRD: The nature of the business or purposes to be conducted or promoted by the
Corporation is as follows:

To engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of Delaware.

FOURTH: The total number of shares of all classes of stock which the Corporation
shall have authority to issue is 62,000,000 shares, consisting of (i) 60,000,000
shares of Common Stock, $0.01 par value per share ("Common Stock"), and (ii)
2,000,000 shares of Preferred Stock, $0.01 par value per share ("Preferred
Stock") which may be issued from time to time in one or more series as set forth
in Part B of this Article FOURTH.

The following is a statement of the designations and the powers, privileges and
rights, and the qualifications, limitations or restrictions thereof in respect
of each class of capital stock of the Corporation.

A. COMMON STOCK

         1. GENERAL. The voting, dividend and liquidation rights of the holders
of the Common Stock are subject to and qualified by the rights of the holders of
the Preferred Stock of any series as may be designated by the Board of Directors
upon any issuance of the Preferred Stock of any series.

         2. VOTING. The holders of the Common Stock are entitled to one vote for
each share held at all meetings of stockholders. There shall be no cumulative
voting. The number of authorized shares of Common Stock may be increased or
decreased (but not below the number of shares thereof then outstanding) by the
affirmative vote of the holders of a majority of the stock of the Corporation
entitled to vote, irrespective of the provisions of Section 242(b)(2) of the
General Corporation Law of Delaware.

         3. DIVIDENDS. Dividends may be declared and paid on the Common Stock
from funds lawfully available therefor as and when determined by the Board of
Directors and subject to any preferential dividend rights of any then
outstanding Preferred Stock.

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         4. LIQUIDATION. Upon the dissolution or liquidation of the Corporation,
whether voluntary or involuntary, holders of Common Stock will be entitled to
receive all assets of the Corporation available for distribution to its
stockholders, subject to any preferential rights of any then outstanding
Preferred Stock.

B. PREFERRED STOCK

Preferred Stock may be issued from time to time in one or more series, each of
such series to have such terms as stated or expressed herein and in the
resolution or resolutions providing for the issue of such series adopted by the
Board of Directors of the Corporation as hereinafter provided. Any shares of
Preferred Stock which may be redeemed, purchased or acquired by the Corporation
may be reissued except as otherwise provided by law. Different series of
Preferred Stock shall not be construed to constitute different classes of shares
for the purposes of voting by classes unless expressly provided.

Authority is hereby expressly granted to the Board of Directors from time to
time to issue the Preferred Stock in one or more series, and in connection with
the creation of any such series, by resolution or resolutions providing for the
issue of the shares thereof, to determine and fix such voting powers, full or
limited, or no voting powers, and such designations, preferences and relative
participating, optional or other special rights, and qualifications, limitations
or restrictions thereof, including without limitation thereof, dividend rights,
conversion rights, redemption privileges and liquidation preferences, as shall
be stated and expressed in such resolutions, all to the full extent now or
hereafter permitted by the General Corporation Law of Delaware. Without limiting
the generality of the foregoing, the resolutions providing for issuance of any
series of Preferred Stock may provide that such series shall be superior or rank
equally or be junior to the Preferred Stock of any other series to the extent
permitted by law. Except as otherwise provided in this Amended and Restated
Certificate of Incorporation, no vote of the holders of the Preferred Stock or
Common Stock shall be a prerequisite to the designation or issuance of any
shares of any series of the Preferred Stock authorized by and complying with the
conditions of this Amended and Restated Certificate of Incorporation, the right
to have such vote being expressly waived by all present and future holders of
the capital stock of the Corporation.

FIFTH: The Corporation shall have a perpetual existence.

SIXTH: In furtherance of and not in limitation of powers conferred by statute,
it is further provided:

         1. Election of directors need not be by written ballot.

         2. The Board of Directors is expressly authorized to adopt, amend or
repeal the By-Laws of the Corporation.

SEVENTH: Except to the extent that the General Corporation Law of Delaware
prohibits the elimination or limitation of liability of directors for breaches
of fiduciary duty, no director of the Corporation shall be personally liable to
the Corporation or its stockholders for monetary damages for any breach of
fiduciary duty as a director, notwithstanding any provision of law imposing such
liability. No amendment to or repeal of this provision shall apply to or have
any


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effect on the liability or alleged liability of any director of the Corporation
for or with respect to any acts or omissions or such director occurring prior to
such amendment.

EIGHTH: The Corporation shall, to the fullest extent permitted by Section 145 of
the General Corporation Law of Delaware, as amended from time to time, indemnify
each person who was or is a party or is threatened to be made a party to any
threatened, pending or completed action, suit or proceeding, whether civil,
criminal, administrative or investigative, by reason of the fact that he or she
is or was, or has agreed to become, a director or officer of the Corporation, or
is or was serving, or has agreed to serve, at the request of the Corporation, as
a director, officer or trustee of, or in a similar capacity with, another
corporation, partnership, joint venture, trust or other enterprise (including
any employee benefit plan) (all such persons being referred to hereafter as an
"Indemnitee"), or by reason of any action alleged to have been taken or omitted
in such capacity, against all expenses (including attorneys' fees), judgments,
fines and amounts paid in settlement actually and reasonably incurred by or on
behalf of an Indemnitee in connection with such action, suit or proceeding and
any appeal therefrom.

As a condition precedent to his or her right to be indemnified, the Indemnitee
must notify the Corporation in writing as soon as practicable of any action,
suit, proceeding or investigation involving him for which indemnity will or
could be sought. With respect to any action, suit, proceeding or investigation
of which the Corporation is so notified, the Corporation will be entitled to
participate therein at its own expense and/or assume the defense thereof at its
own expense, with legal counsel reasonably acceptable to the Indemnitee.

In the event that the Corporation does not assume the defense of any action,
suit, proceeding or investigation of which the Corporation receives notice under
this Article, the Corporation shall pay in advance of the final disposition of
such matter any expenses (including attorneys' fees) incurred by an Indemnitee
in defending a civil or criminal action, suit, proceeding or investigation or
any appeal therefrom; PROVIDED, HOWEVER, that the payment of such expenses
incurred by an Indemnitee in advance of the final disposition of such matter
shall be made only upon receipt of any undertaking by or on behalf of the
Indemnitee to repay all amounts so advanced in the event that it shall
ultimately be determined that the Indemnitee is not entitled to be indemnified
by the Corporation as authorized in this Article, which undertaking shall be
accepted without reference to the financial ability of the Indemnitee to make
such repayment; and FURTHER, PROVIDED that no such advancement of expenses shall
be made if it is determined that (i) the Indemnitee did not act in good faith
and in a manner he reasonably believed to be in, or not opposed to, the best
interests of the Corporation, or (ii) with respect to any criminal action or
proceeding, the Indemnitee had reasonable cause to believe his conduct was
unlawful.

The Corporation shall not indemnify an Indemnitee seeking indemnification in
connection with a proceeding (or part thereof) initiated by such Indemnitee
unless the initiation thereof was approved by the Board of Directors of the
Corporation. In addition, the Corporation shall not indemnify an Indemnitee to
the extent such Indemnitee is reimbursed from the proceeds of insurance, and in
the event the Corporation makes any indemnification payments to an Indemnitee
and such Indemnitee is subsequently reimbursed from the proceeds of insurance,
such Indemnitee shall promptly refund such indemnification payments to the
Corporation to the extent of such insurance reimbursement.

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All determinations hereunder as to the entitlement of an Indemnitee to
indemnification or advancement of expenses shall be made in each instance by (a)
a majority vote of the directors of the Corporation consisting of persons who
are not at that time parties to the action, suit or proceeding in question
("disinterested directors"), whether or not a quorum, (b) a majority vote of a
quorum of the outstanding shares of stock of all classes entitled to vote for
directors, voting as a single class, which quorum shall consist of stockholders
who are not at that time parties to the action, suit or proceeding in question,
(c) independent legal counsel (who may, to the extent permitted by law, be
regular legal counsel to the Corporation), or (d) a court of competent
jurisdiction.

The indemnification rights provided in this Article (i) shall not be deemed
exclusive of any other rights to which an Indemnitee may be entitled under any
law, agreement or vote of stockholders or disinterested directors or otherwise,
and (ii) shall inure to the benefit of the heirs, executors and administrators
of the Indemnitees. The Corporation may, to the extent authorized from time to
time by its Board of Directors, grant indemnification rights to other employees
or agents of the Corporation or other persons serving the Corporation and such
rights may be equivalent to, or greater or less than, those set forth in this
Article.

NINTH: The Corporation reserves the right to amend, alter, change or repeal any
provision contained in this Amended and Restated Certificate of Incorporation,
in the manner now or hereafter prescribed by statute and this Amended and
Restated Certificate of Incorporation, and all rights conferred upon
stockholders herein are granted subject to this reservation.

TENTH: This Article is inserted for the management of the business and for the
conduct of the affairs of the Corporation.

         1. NUMBER OF DIRECTORS. The exact number of directors shall be fixed
from time to time by, or in the manner provided in, the Corporation's By-Laws.

         2. ELECTION OF DIRECTORS. Elections of directors need not be by written
ballot except as and to the extent provided in the By-Laws of the Corporation.

         3. TERMS OF OFFICE. Each director shall serve for a term ending on the
date of the first annual meeting following the annual meeting at which such
director was elected; PROVIDED, that the term of each director shall be subject
to the election and qualification of his or her successor and to his or her
earlier death, resignation or removal.

         4. QUORUM; ACTION AT MEETING. A majority of the total number of the
whole Board of Directors shall constitute a quorum at all meetings of the Board
of Directors. In the event one or more of the directors shall be disqualified to
vote at any meeting, then the required quorum shall be reduced by one for each
such director so disqualified; provided, however, that in no case shall less
than one-third of the number fixed pursuant to Section 1 above constitute a
quorum. In the absence of a quorum at any such meeting, a majority of the
directors present may adjourn the meeting from time to time without further
notice other than announcement at the meeting, until a quorum shall be present.
At any meeting of the Board of Directors at which a quorum is present, the vote
of a majority of those present shall be sufficient to take any action, unless a
different


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vote is specified by law, by the By-Laws of the Corporation or by this Amended
and Restated Certificate of Incorporation.

         5. REMOVAL. Directors of the Corporation may be removed only for cause
by the affirmative vote of the holders of at least seventy-five percent (75%) of
the shares of the capital stock of the Corporation issued and outstanding and
entitled to vote.

         6. VACANCIES. Any vacancy in the Board of Directors, however occurring,
including a vacancy resulting from an enlargement of the board, shall be filled
only by a vote of a majority of the directors then in office, although less than
a quorum, or by a sole remaining director. A director elected to fill a vacancy
shall be elected to hold office until the next election of directors, subject to
the election and qualification of his or her successor and to his or her earlier
death, resignation or removal.

         7. STOCKHOLDER NOMINATIONS AND INTRODUCTION OF BUSINESS, ETC. Advance
notice of stockholder nominations for election of directors and other business
to be brought by stockholders before a meeting of stockholders shall be given in
the manner provided by the By-Laws of the Corporation.

ELEVENTH. Stockholders of the Corporation may not take any action by written
consent in lieu of a meeting. Notwithstanding any other provisions of law, the
Amended and Restated Certificate of Incorporation or the By-Laws of the
Corporation, and notwithstanding the fact that a lesser percentage may be
specified by law, the affirmative vote of the holders of at least seventy-five
percent (75%) of the shares of capital stock of the Corporation issued and
outstanding and entitled to vote shall be required to amend or repeal, or to
adopt any provision inconsistent with, this Article ELEVENTH.

TWELFTH. Special meetings of stockholders may be called at any time only by the
Chairman of the Board of Directors, the President or the Board of Directors.
Business transacted at any special meeting of stockholders shall be limited to
matters relating to the purpose or purposes stated in the notice of meeting.
Notwithstanding any other provision of law, this Amended and Restated
Certificate of Incorporation or the By-Laws of the Corporation, and
notwithstanding the fact that a lesser percentage may be specified by law, the
affirmative vote of the holders of at least seventy-five percent (75%) of the
shares of capital stock of the Corporation issued and outstanding and entitled
to vote shall be required to amend or repeal, or to adopt any provision
inconsistent with, this Article TWELFTH.

THIRTEENTH. In addition to any other considerations which the Board of Directors
may lawfully take into account in determining whether to take or to refrain from
taking corporate action on any matter, including proposing any matter to the
stockholders of the Corporation, the Board of Directors may take into account
the interests of creditors, customers, employees and other constituencies of the
Corporation and its subsidiaries and the effect thereof upon communities in
which the Corporation and its subsidiaries do business. Notwithstanding any
other provision of law, this Amended and Restated Certificate of Incorporation
or the By-Laws of the Corporation, and notwithstanding the fact that a lesser
percentage may be specified by law, the affirmative vote of the holders of at
least seventy-five percent (75%) of the shares of


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capital stock of the Corporation issued and outstanding and entitled to vote
shall be required to amend or repeal, or to adopt any provision inconsistent
with, this Article THIRTEENTH.

FOURTEENTH. In furtherance and not in limitation of the powers conferred by law
or in this Amended and Restated Certificate of Incorporation, the Board of
Directors (and any committee of the Board of Directors) is expressly authorized
to take such action or actions as the Board or such committee may determine to
be reasonably necessary or desirable to (a) encourage any person to enter into
negotiations with the Board of Directors and management of the Corporation with
respect to any transaction which may result in a change in control of the
Corporation which is proposed or initiated by such person, or (b) contest or
oppose any such transaction which the Board of Directors or such committee
determines to be unfair, abusive or otherwise undesirable with respect to the
Corporation and its business, assets or properties or the stockholders of the
Corporation, including, without limitation, the adoption of such plans or the
issuance of such rights, options, capital stock, notes, debentures or other
evidence of indebtedness or other securities of the Corporation, which rights,
options, capital stock, notes, debentures or other evidences of indebtedness and
other securities (i) may be exchangeable for or convertible into cash or other
securities on such terms and conditions as may be determined by the Board of
Directors (or any such committee) and (ii) may provide for the treatment of any
holder or class of holders thereof designated by the Board of Directors (or any
such committee) in respect of the terms, conditions, provisions and rights of
such securities which is different from, and unequal to, the terms, conditions,
provisions and rights applicable to all other holders thereof. Notwithstanding
any other provision of law, this Amended and Restated Certificate of
Incorporation or the By-Laws of the Corporation, and notwithstanding the fact
that a lesser percentage may be specified by law, the affirmative vote of the
holders of at least seventy-five percent (75%) of the shares of capital stock of
the Corporation issued and outstanding and entitled to vote shall be required to
amend or repeal, or to adopt any provision inconsistent with, this Article
FOURTEENTH.

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         IN WITNESS WHEREOF, the Corporation has caused its corporate seal to be
affixed hereto and this Certificate of Incorporation to be signed by its
President this 13th day of September, 2000.

                                               NEON COMMUNICATIONS, INC.



                                               By: /s/ VICTOR COLANTONIO
                                                   ----------------------------
                                                   Victor Colantonio, President