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                                                                     EXHIBIT 3.1

                             AMENDED AND RESTATED

                         CERTIFICATE OF INCORPORATION

                                      OF

                                 NEW RES, INC.


     This Amended and Restated Certificate of Incorporation of New RES, Inc., a
corporation incorporated under the General Corporation Law of the State of
Delaware (the "Corporation") on May 30, 1997, has been duly adopted and
executed in accordance with the provisions of Sections 103, 242 and 245 of the
General Corporation Law of the State of Delaware.  The undersigned, being an
authorized officer of the Corporation, hereby certifies that:

     FIRST:  The name of the Corporation is New RES, Inc.

     SECOND: The address of the registered office of the Corporation in the
State of Delaware is c/o The Corporation Trust Company, Corporation Trust
Center, 1209 Orange Street, City of Wilmington, County of New Castle, State of
Delaware 19801.  The name of the registered agent of the Corporation in the
State of Delaware at such address is The Corporation Trust Company.

     THIRD:  The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware, as from time to time amended.

     FOURTH: The total number of shares of stock which the Corporation shall
have authority to issue is 510,000,000 shares of capital stock, classified as
(i) 10,000,000 shares of preferred stock, par value $0.001 per share 
("Preferred Stock"), and (ii) 500,000,000 shares of common stock, par value 
$0.001 per share ("Common Stock").

     1.  Provisions Relating to Preferred Stock.

     Shares of Preferred Stock may be issued from time to time in one or more
series, the shares of each series to
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have 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, as shall be
stated and expressed in a resolution or resolutions providing for the issue of
such series adopted by the Board of Directors of the Corporation.  The Board of
Directors of the Corporation is hereby expressly authorized to establish and
designate series of Preferred Stock, to fix the number of shares constituting
each series, and to fix the designations and the powers, rights, preferences,
and relative, participating, optional or other special rights and
qualifications, limitations and restrictions of the shares of each series and
the variations of the relative designations, powers, rights, preferences and
relative, participating, optional or other special rights and qualifications,
limitations and restrictions as between series, and to increase (but not above
the total number of authorized shares of such class) and to decrease (but not
below the number of shares thereof then outstanding) the number of shares
constituting each series.

     2.  Provisions Relating to Common Stock.

     (a) Each share of Common Stock of the Corporation shall have identical
rights and privileges in every respect. The holders of shares of Common Stock
shall be entitled to vote upon all matters submitted to a vote of the
stockholders of the Corporation and shall be entitled to one vote for each share
of Common Stock held.

     (b) Subject to the prior rights and preferences, if any, applicable to
shares of Preferred Stock or any series thereof, the holders of shares of Common
Stock shall be entitled to receive such dividends (payable in cash, stock or
otherwise) as may be declared thereon by the Board of Directors at any time and
from time to time out of any funds of the Corporation legally available 
therefor.

     (c) In the event of any voluntary or involuntary liquidation, dissolution
or winding-up of the Corporation, after distribution in full of the preferential
amounts, if any, to be distributed to the holders of shares of Preferred Stock
or any series thereof, the holders of shares of Common Stock shall be entitled
to receive all of the remaining assets of the Corporation available for
distribution to its stockholders, ratably in proportion to the number of shares
 

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of Common Stock held by them.  A liquidation, dissolution or winding-up of the
Corporation, as such terms are used in this Paragraph (c), shall not be deemed
to be occasioned by or to include any consolidation or merger of the Corporation
with or into any other corporation or corporations or other entity or a sale,
lease, exchange or conveyance of all or a part of the assets of the Corporation.

     FIFTH:  In furtherance and not in limitation of the powers conferred by
law, subject to any limitations contained elsewhere in this Amended and Restated
Certificate of Incorporation, bylaws of the Corporation may be adopted, amended
or repealed by a majority of the Board of Directors of the Corporation, but any
bylaws adopted by the Board of Directors may be amended or repealed by the
stockholders entitled to vote thereon.  Election of directors need not be by
written ballot.

     SIXTH:  (a)  A director of the Corporation shall not be personally liable
either to the Corporation or to any stockholder for monetary damages for breach
of fiduciary duty as a director, except (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, or (ii) for acts or
omissions which are not in good faith or which involve intentional misconduct or
knowing violation of the law, or (iii) for any matter in respect of which such
director shall be liable under Section 174 of Title 8 of the General Corporation
Law of the State of Delaware or any amendment thereto or successor provision
thereto, or (iv) for any transaction from which the director shall have derived
an improper personal benefit.  Neither amendment nor repeal of this paragraph
(a), nor the adoption of any provision of this Amended and Restated Certificate
of Incorporation inconsistent with this paragraph (a) shall eliminate or reduce
the effect of this paragraph (a) in respect of any matter occurring, or any
cause of action, suit or claim that, but for this paragraph (a), would accrue or
arise, prior to such amendment, repeal or adoption of an inconsistent provision.

     (b) The Corporation shall indemnify any person who was or is a party or is
threatened to be made a party to, or testifies in, any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative in nature, by reason of the

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fact that such person is or was a director, officer, employee or agent of the
Corporation, or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, employee benefit plan, trust or other enterprise, against expenses
(including attorneys' fees), judgments, fines and amounts paid in settlement
actually and reasonably incurred by such person in connection with such action,
suit or proceeding to the full extent permitted by law, and the Corporation may
adopt bylaws or enter into agreements with any such person for the purpose of
providing for such indemnification.

     (c) To the extent that a director or officer of the Corporation has been
successful on the merits or otherwise in defense of any action, suit or
proceeding referred to in paragraph (b) of this Article, or in defense of any
claim, issue or matter therein, such person shall be indemnified against
expenses (including attorneys' fees) actually and reasonably incurred by such
person in connection therewith.

     (d) Expenses incurred by an officer, director, employee or agent in
defending or testifying in a civil, criminal, administrative or investigative
action, suit or proceeding may be paid by the Corporation in advance of the
final disposition of such action, suit or proceeding upon receipt of an
undertaking by or on behalf of such director or officer to repay such amount if
it shall ultimately be determined that such director or officer is not entitled
to be indemnified by the Corporation against such expense as authorized by this
Article, and the Corporation may adopt bylaws or enter into agreements with such
persons for the purpose of providing for such advances.

     IN WITNESS WHEREOF, the undersigned has duly executed this Amended and
Restated Certificate of Incorporation on this 9th day of October, 1997.


                                                New RES, Inc.

                                                By: /s/ John J. McLaine
                                                   -----------------------------
                                                Name:  John J. McLaine
                                                Title:  Executive Vice 
                                                        President and Secretary

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                           CERTIFICATE OF AMENDMENT
                          TO THE AMENDED AND RESTATED
                         CERTIFICATE OF INCORPORATION
                                      OF
                                 NEW RES, INC.


     New RES, Inc., a corporation organized and existing under the laws of the
State of Delaware (the "Corporation"), does hereby certify as follows:

     1.  The name of the Corporation is New RES, Inc. and the original
Certificate of Incorporation of the Corporation was filed with the office of the
Secretary of State of the State of Delaware on May 30, 1997.

     2.  This Certificate of Amendment to the Corporation's Amended and Restated
Certificate of Incorporation has been duly adopted and executed in accordance
with the provisions of Sections 103 and 242 of the General Corporation Law of
the State of Delaware (the "DGCL").

     3.  The text of paragraph First of the Corporation's Amended and Restated
Certificate of Incorporation is hereby amended and restated in its entirety to
read as follows:

     FIRST:  The name of the Corporation (hereinafter referred to as the
     "Corporation") is

             EXCEL Communications, Inc.

     4.  The holders of all of the shares of the common stock, par value $0.00l
per share, of the Corporation which are outstanding and entitled to vote on the
amendment set forth above have signed a Unanimous Written Consent pursuant to
Section 228 of the DGCL adopting such amendment.
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     IN WITNESS WHEREOF, the Corporation has caused this Certificate of 
Amendment to be signed by a duly authorized officer this 14th day of October,
1997.

                                        NEW RES, INC.


                                        By: /s/ JOHN J. MCLAINE
                                           -------------------------------------
                                        Name: John J. McLaine
                                        Title: President and
                                                Chief Operating Officer

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