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                            CERTIFICATE OF AMENDMENT

                                     TO THE

                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                                 NET2PHONE, INC.

         NET2PHONE, INC., a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware (hereinafter the
"Corporation"), DOES HEREBY CERTIFY THAT:

         1. The Corporation's Certificate of Incorporation was initially filed
    with the Secretary of State of the State of Delaware on October 10, 1997 and
    was amended and restated on May 14, 1999.

         2. At a meeting of the Board of Directors of the Corporation,
    resolutions were duly adopted setting forth proposed amendments to the
    Amended and Restated Certificate of Incorporation, declaring said amendments
    to be advisable and calling a meeting of the stockholders of the Corporation
    for consideration thereof. The resolutions setting forth the proposed
    amendments are attached hereto as Exhibit A and incorporated herein by
    reference.

         3. Thereafter, pursuant to a resolution of the Board of Directors, a
    special meeting of the stockholders of the Corporation was duly called and
    held, upon notice in accordance with Section 222 of the General Corporation
    Law of the State of Delaware, at which meeting the necessary number of
    shares as required by statute were voted in favor of the amendments.

         4. Said amendments were duly adopted in accordance with the provisions
    of Section 242 of the General Corporation Law of the State of Delaware.

         IN WITNESS WHEREOF, Net2Phone, Inc. has caused this Certificate of
    Amendment to be signed and attested by its duly authorized officer, this 7th
    day of July, 2000.

                                  NET2PHONE, INC.

                                  By:    /s/ Glenn Williams
                                     ----------------------

                                  Name:  Glenn Williams
                                         --------------

                                  Title: General Counsel and Corporate Secretary
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                                    EXHIBIT A

                     RESOLUTIONS OF THE BOARD OF DIRECTORS

                               OF NET2PHONE, INC.

         1. RESOLVED, that the first sentence of the Preamble of ARTICLE FOURTH
to the Corporation's Amended and Restated Certificate of Incorporation be
amended and restated to read as follows:

         "ARTICLE FOURTH: The aggregate number of shares of all classes of
         capital stock which the Corporation shall have the authority to issue
         is 247,924,250 shares, consisting of (a) 200,000,000 shares of common
         stock, par value $0.01 per share ("Common Stock"), (b) 37,924,250
         shares of Class A common stock, par value $0.01 per share (the "Class A
         Stock" and, together with the Common Stock, the "Common Shares"), and
         (c) 10,000,000 shares of preferred stock, par value $0.01 per share
         ("Preferred Stock")."

         2. RESOLVED, that the first sentence of ARTICLE FOURTH, Paragraph
1(h)(1) to the Corporation's Amended and Restated Certificate of Incorporation
be amended and restated as follows:

         "Following issuance of the Series A Preferred and for so long as shares
         of Series A Preferred remain outstanding, the holders of the Series A
         Preferred, voting as a separate class, shall be entitled to elect 2
         directors (the "Series A Directors")."

         3. RESOLVED, that the first sentence of ARTICLE FIFTH to the
Corporation's Amended and Restated Certificate of Incorporation be amended and
restated as follows:

         "The business and affairs of the Corporation shall be managed by or
         under the direction of a Board of Directors consisting of not less than
         five (5) and not more than thirteen (13) directors, the exact number of
         which shall be fixed from time to time by the Board of Directors."



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