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                              AMENDED AND RESTATED

                                     BYLAWS

                                       OF

                                 RCN CORPORATION

                                    * * * * *

                                    ARTICLE I

                                     OFFICES

                  Section 1. Registered Office. The registered office shall be
in the City of Wilmington, County of New Castle, State of Delaware.

                  Section 2. Other Offices. The Corporation may also have
offices at such other places both within and without the State of Delaware as
the Board of Directors may from time to time determine or the business of the
Corporation may require.

                  Section 3. Books. The books of the Corporation may be kept
within or without of the State of Delaware as the Board of Directors may from
time to time determine or the business of the Corporation may require.

                                   ARTICLE II

                            MEETINGS OF STOCKHOLDERS

               Section 1. Time and Place of Meetings. All meetings of
stockholders shall be held at such place, either within or without the State of
Delaware, on such date and at such time as may be determined from time to time
by the Board of Directors (or the Chairman in the absence of a designation by
the Board of Directors).

               Section 2. Annual Meetings. Annual meetings of stockholders,
commencing with the year 1998, shall be held to elect directors and transact
such other business as may properly be brought before the meeting.

               Section 3. Special Meetings. Special meetings of stockholders may
be called by the Board of Directors, the Chairman or the Chief Executive Officer
of the Corporation and may not be called by any other person. Notwithstanding
the foregoing, whenever holders of one or more classes or series of Preferred
Stock shall have the right, voting separately as a class or series, to elect
directors, such holders may call, pursuant to the terms of the resolution or
resolutions adopted by the Board of Directors pursuant to Article Fourth of the
certificate of incorporation, special meetings of holders of such Preferred
Stock.
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               Section 4. Notice of Meetings and Adjourned Meetings; Waivers of
Notice; Business at Meetings. (a) Whenever stockholders are required or
permitted to take any action at a meeting, a written notice of the meeting shall
be given which shall state the place, date and hour of the meeting, and, in the
case of a special meeting, the purpose or purposes for which the meeting is
called. Unless otherwise provided by the General Corporation Law of the State of
Delaware as the same exists or may hereafter be amended ("Delaware Law"), such
notice shall be given not less than 10 nor more than 60 days before the date of
the meeting to each stockholder of record entitled to vote at such meeting.
Unless these bylaws otherwise require, when a meeting is adjourned to another
time or place (whether or not a quorum is present), notice need not be given of
the adjourned meeting if the time and place thereof are announced at the meeting
at which the adjournment is taken. At the adjourned meeting, the Corporation may
transact any business which might have been transacted at the original meeting.
If the adjournment is for more than 30 days, or after the adjournment a new
record date is fixed for the adjourned meeting, a notice of the adjourned
meeting shall be given to each stockholder of record entitled to vote at the
meeting.

               (b) A written waiver of any such notice signed by the person
entitled thereto, whether before or after the time stated therein, shall be
deemed equivalent to notice. Attendance of a person at a meeting shall
constitute a waiver of notice of such meeting, except when the person attends
the meeting for the express purpose of objecting, at the beginning of the
meeting, to the transaction of any business because the meeting is not lawfully
called or convened.

               (c) Business transacted at any special meeting of stockholders
shall be limited to the purposes stated in the notice.

               Section 5. Quorum. Unless otherwise provided under the
certificate of incorporation or these bylaws and subject to Delaware Law, the
presence, in person or by proxy, of the holders of a majority of the outstanding
capital stock of the Corporation entitled to vote at a meeting of stockholders
shall constitute a quorum for the transaction of business. A quorum, once
established, shall not be broken by the withdrawal of enough votes to leave less
than a quorum. If, however, such quorum shall not be present or represented at
any meeting of the stockholders, the stockholders entitled to vote thereat,
present in person or by proxy, shall have the power to adjourn the meeting from
time to time, in the manner provided in Section 4, until a quorum shall be
present or represented.

               Section 6. Voting. (a) Unless otherwise provided in the
certificate of incorporation and subject to Delaware Law, each stockholder shall
be entitled to one vote for each outstanding share of capital stock of the
Corporation held by such stockholder. Unless otherwise provided in Delaware Law,
the certificate of incorporation or these bylaws, the affirmative vote of a
majority of the total number of votes of the shares of capital stock of the
Corporation present, in person or by proxy, at a meeting of stockholders and
entitled to vote on the subject matter shall be the act of the stockholders,
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other than with respect to the election of directors. Except as otherwise
provided in the certificate of incorporation and these bylaws, directors shall
be elected by a plurality of the votes cast at the meeting and entitled to vote
on the election of directors.

               (b) Each stockholder entitled to vote at a meeting of
stockholders or to express consent or dissent to a corporate action in writing
without a meeting may authorize another person or persons to act for him by
proxy, but no such proxy shall be voted or acted upon after one year from its
date, unless the proxy provides for a longer period.

               Section 7. No Action by Consent. Any action required or permitted
to be taken at any annual or special meeting of stockholders may be taken only
upon the vote of stockholders entitled to vote thereon at an annual or special
meeting duly noticed and called in accordance with Delaware Law and may not be
taken by written consent of stockholders without a meeting.

               Section 8. Organization. At each meeting of stockholders, the
Chairman, if one shall have been elected, (or in his absence or if one shall not
have been elected, the Chief Executive Officer) shall act as chairman of the
meeting. The Secretary (or in his absence or inability to act, the person whom
the chairman of the meeting shall appoint secretary of the meeting) shall act as
secretary of the meeting and keep the minutes thereof.

               Section 9. Order of Business. The order of business at all
meetings of stockholders shall be as determined by the chairman of the meeting.

               Section 10. Notice of Business. At any meeting of the
stockholders, only such business shall be conducted as shall have been brought
before the meeting (a) by or at the direction of the Board of Directors or (b)
in the case of an annual meeting of stockholders, by any stockholder of the
Corporation who is a stockholder of record at the time of giving of the notice
provided for in this Section 10, who shall be entitled to vote at such meeting
and who complies with the notice procedures set forth in this Section 10. For
business to be properly brought before an annual meeting of stockholders by a
stockholder, the stockholder must have given timely notice thereof in writing to
the secretary of the Corporation. To be timely, a stockholder's notice shall be
delivered to or mailed and received at the principal executive offices of the
Corporation not less than 60 days nor more than 90 days prior to the meeting;
provided, however, that in the event that less than 70 days' notice or prior
public disclosure of the date of the meeting is given or made to stockholders,
notice by the stockholder to be timely must be so received not later than the
close of business on the 10th day following the day on which such notice of the
date of the meeting or such public disclosure was given or made, whichever first
occurs. A stockholder's notice to the secretary shall set forth as to each
matter the stockholder proposes to bring before the meeting (a) a brief
description of the business desired to be brought before the meeting and the
reasons for conducting such business at the meeting, (b) the name and address,
as they appear on the Corporation's books, of the stockholder proposing such
business, (c) the class and number of shares of the Corporation which are
beneficially owned by the stockholder and (d) any material interest of the
stockholder in such business. Notwithstanding anything in the bylaws to the
contrary, no business shall
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be conducted at a stockholder meeting except in accordance with the procedures
set forth in this Section 10, and no business shall be brought by a stockholder
before a special meeting of stockholders. The chairman of the meeting shall, if
the facts warrant, determine and declare to the meeting that business was not
properly brought before the meeting and in accordance with the provisions of the
bylaws, and if he should so determine, he shall so declare to the meeting and
any such business not properly brought before the meeting shall not be
transacted. Notwithstanding the foregoing, provisions of this Section 10, a
stockholder shall also comply with all applicable requirements of the Securities
Exchange Act of 1934, and the rules and regulations thereunder with respect to
the matters set forth in this Section 10.

               Section 11. Nomination of Directors. Only persons who are
nominated in accordance with the procedures set forth in these bylaws shall be
eligible to serve as directors. Nominations of persons for election to the Board
of Directors of the Corporation may be made at a meeting of stockholders (a) by
or at the direction of the Board of Directors or (b) by any stockholder of the
Corporation who is a stockholder of record at the time of giving of notice
provided for in this Section 11, who shall be entitled to vote for the election
of directors at the meeting and who complies with the notice procedures set
forth in this Section 11. Such nominations, other than those made by or at the
direction of the Board of Directors, shall be made pursuant to timely notice in
writing to the secretary of the Corporation. To be timely, a stockholder's
notice shall be delivered to or mailed and received at the principal executive
offices of the Corporation not less than 60 days nor more than 90 days prior to
the meeting; provided, however, that in the event that less than 70 days' notice
or prior public disclosure of the date of the meeting is given or made to
stockholders, notice by the stockholder to be timely must be so received not
later than the close of business on the 10th day following the day on which such
notice of the date of the meeting or such public disclosure was given or made,
whichever first occurs. Such stockholder's notice shall set forth (a) as to each
person whom the stockholder proposes to nominate for election or reelection as a
director all information relating to such person that is required to be
disclosed in solicitations of proxies for election of directors, or is otherwise
required, in each case pursuant to Regulation 14A under the Securities Exchange
Act of 1934 (including such person's written consent to being named in the proxy
statement as a nominee and to serving as a director if elected); and (b) as to
the stockholder giving the notice (i) the name and address, as they appear on
the Corporation's books, of such stockholder, (ii) the class and number of
shares of the Corporation which are beneficially owned by such stockholder,
(iii) a description of all arrangements or understandings between such
stockholder and each proposed nominee and any other person or persons (including
their names and addresses) pursuant to which the nomination(s) are to be made by
such stockholder and (iv) any other information relating to such stockholder
that is required to be disclosed in solicitations of proxies for election of
directors, or is otherwise required, in each case pursuant to Section 14A under
the Securities Exchange Act of 1934. At the request of the Board of Directors,
any person nominated by the Board of Directors for election as a director shall
furnish to the secretary of the Corporation that information required to be set
forth in a stockholder's notice of nomination which pertains to the nominee. No
person shall be eligible to serve as a director of the Corporation unless
nominated in accordance with the procedures set
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forth in this bylaw. The chairman of the meeting shall, if the facts warrant,
determine and declare to the meeting that a nomination was not made in
accordance with the procedures prescribed by the bylaws, and if he should so
determine, he shall so declare to the meeting and the defective nomination shall
be disregarded. Notwithstanding the foregoing provisions of this Section 11, a
stockholder shall also comply with all applicable requirements of the Securities
Exchange Act of 1934, and the rules and regulations thereunder with respect to
the matters set forth in this Section.

                                   ARTICLE III

                                    DIRECTORS

               Section 1. General Powers. Except as otherwise provided in
Delaware Law or the certificate of incorporation, the business and affairs of
the Corporation shall be managed by or under the direction of the Board of
Directors.

               Section 2. Number, Classes, Term of Office, etc. The Board of
Directors shall consist of not less than three nor more than twenty-four
directors, with the exact number of directors to be determined from time to time
solely by resolution adopted by the affirmative vote of a majority of the entire
Board of Directors. The directors shall be divided into three classes,
designated Class I, Class II and Class III. Each class shall consist, as nearly
as may be possible, of one-third of the total number of directors constituting
the entire Board of Directors. Except as otherwise provided in the certificate
of incorporation, each director shall serve for a term ending on the date of the
third annual meeting of stockholders next following the annual meeting at which
such director was elected. Notwithstanding the foregoing, each director shall
hold office until such director's successor shall have been duly elected and
qualified or until such director's earlier death, resignation or removal.
Directors need not be stockholders.

               Section 3. Quorum and Manner of Acting. Unless the certificate of
incorporation or these bylaws require a greater number, 50% of the total number
of directors serving as directors shall constitute a quorum for the transaction
of business, and the affirmative vote of a majority of the directors present at
a meeting at which a quorum is present shall be the act of the Board of
Directors. When a meeting is adjourned to another time or place (whether or not
a quorum is present), notice need not be given of the adjourned meeting if the
time and place thereof are announced at the meeting at which the adjournment is
taken. At the adjourned meeting, the Board of Directors may transact any
business which might have been transacted at the original meeting. If a quorum
shall not be present at any meeting of the Board of Directors, the directors
present at such meeting may adjourn the meeting, from time to time, without
notice other than announcement at the meeting, until a quorum shall be present.

               Section 4. Time and Place of Meetings. The Board of Directors
shall hold its meetings at such place, either within or without the State of
Delaware, and at such time as may be determined from time to time by the Board
of Directors (or the Chairman in the absence of a determination by the Board of
Directors).
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               Section 5. Annual Meeting. The Board of Directors shall meet for
the purpose of electing officers and transacting other business, as soon as
practicable after each annual meeting of stockholders, on the same day and at
the same place where such annual meeting shall be held. Notice of such meeting
need not be given. In the event such annual meeting is not so held, the annual
meeting of the Board of Directors may be held at such place either within or
without the State of Delaware, on such date and at such time as shall be
specified in a notice thereof given as hereinafter provided in Section 7 of this
Article III or in a waiver of notice thereof signed by any director who chooses
to waive the requirement of notice.

               Section 6. Regular Meetings. After the place and time of regular
meetings of the Board of Directors shall have been determined and notice thereof
shall have been once given to each member of the Board of Directors, regular
meetings may be held without further notice being given.

               Section 7. Special Meetings. Special meetings of the Board of
Directors may be called by the Chairman, the Chief Executive Officer or the
President and shall be called by the Chairman, the Chief Executive Officer, the
President or the Secretary on the written request of three directors. Notice of
special meetings of the Board of Directors shall be given to each director at
least three days before the date of the meeting in such manner as is determined
by the Board of Directors.

         Section 8. Waiver of Notice. Whenever any notice is required by law,
the certificate of incorporation or these bylaws to be given to any director or
member of a committee, a waiver thereof in writing, signed, by the person or
persons entitled to said notice, whether before or after the time stated
therein, shall be deemed equivalent to notice. Attendance of a person at a
meeting shall constitute a waiver of notice of such meeting, except where the
person attends the meeting for the express purpose of objecting, at the
beginning of the meeting, to the transaction of any business because the meeting
is not lawfully called or convened.

               Section 9. Committees. The Board of Directors shall elect from
the directors an executive committee, a compensation committee and an audit
committee and may, by resolution passed by a majority of the whole Board,
designate one or more other committees, each committee to consist of one or more
of the directors of the Corporation. Each committee shall keep regular minutes
of its meetings and report the same to the Board of Directors when required. The
specific powers and duties of the executive committee, the compensation
committee and the audit committee are set forth below:

              (a) The executive committee shall consist of not less than 3 and
                  not more than 6 members as shall be determined by the Board of
                  Directors in addition to the Chairman, who by virtue of his
                  office shall be a member of the executive committee and
                  chairman thereof. To the fullest extent permitted by Delaware
                  Law, the executive committee shall
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                  have all the powers of the Board of Directors in the
                  management of the business and affairs of the Corporation at
                  all times when the Board of Directors is not in session.

              (b) The compensation committee shall consist of such number of
                  members as shall be determined by the Board of Directors,
                  shall make recommendations to the Board of Directors regarding
                  compensation and benefits and shall have such other duties as
                  determined by the Board of Directors.

              (c) The audit committee shall consist of such number of members as
                  shall be determined by the Board of Directors, shall make
                  recommendations to the Board of Directors regarding the
                  auditing of the Corporation's books and records, the audit
                  process and the Corporation's independent public accountants
                  and shall have such other duties as determined by the Board of
                  Directors. None of the members of the audit committee shall be
                  directly involved in the supervision or management of the
                  financial affairs of this Corporation or any of its
                  subsidiaries.

               Section 10. Action by Consent. Unless otherwise restricted by the
certificate of incorporation or these bylaws, any action required or permitted
to be taken at any meeting of the Board of Directors or of any committee thereof
may be taken without a meeting, if all members of the Board or committee, as the
case may be, consent thereto in writing or by electronic transmission, and the
writing or writings or electronic transmission or transmissions are filed with
the minutes of proceedings of the Board or committee. Such filing shall be in
paper form if the minutes are maintained in paper form and shall be in
electronic form if the minutes are maintained in electronic form.

               Section 11. Telephonic Meetings. Unless otherwise restricted by
the certificate of incorporation or these bylaws, members of the Board of
Directors, or any committee thereof, may participate in a meeting of the Board
of Directors, or such committee, as the case may be, by means of conference
telephone or other communications equipment by means of which all persons
participating in the meeting can hear each other, and such participation in a
meeting shall constitute presence in person at the meeting.

               Section 12. Resignation. Any director may resign at any time by
giving written notice to the Board of Directors or to the Secretary of the
Corporation. The resignation of any director shall take effect upon receipt of
notice thereof or at such later time as shall be specified in such notice; and
unless otherwise specified therein, the acceptance of such resignation shall not
be necessary to make it effective.

               Section 13. Vacancies. Unless otherwise provided in the
certificate of incorporation, vacancies on the Board of Directors resulting from
death, resignation, removal or otherwise and newly created directorships
resulting from any increase in the
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number of directors may be filled solely by a majority of the directors then in
office (even if less than a quorum) or by the sole remaining director. Each
director so elected shall hold office for a term that shall coincide with the
term of the Class to which such director shall have been elected. If there are
no directors in office, then an election of directors may be held in accordance
with Delaware Law. Unless otherwise provided in the certificate of
incorporation, when one or more directors shall resign from the Board, effective
at a future date, a majority of the directors then in office, including those
who have so resigned, shall have the power to fill such vacancy or vacancies,
the vote thereon to take effect when such resignation or resignations shall
become effective, and each director so chosen shall hold office as provided in
the filling of other vacancies.

               Section 14. Removal. No director may be removed from office by
the stockholders except for cause with the affirmative vote of the holders of
not less than a majority of the total voting power of all outstanding securities
of the corporation then entitled to vote generally in the election of directors,
voting together as a single class.

                  Section 15. Compensation. Unless otherwise restricted by the
certificate of incorporation or these bylaws, the Board of Directors shall have
authority to fix the compensation of directors, including fees and reimbursement
of expenses.

               Section 16. Preferred Directors. Notwithstanding anything else
contained herein, whenever the holders of one or more classes or series of
Preferred Stock shall have the right, voting separately as a class or series, to
elect directors, the election, term of office, filling of vacancies, removal and
other features of such directorships shall be governed by the terms of the
resolutions adopted by the Board of Directors pursuant to the certificate of
incorporation applicable thereto, and such directors so elected shall not be
subject to the provisions of Sections 2, 13 and 14 of this Article III unless
otherwise provided therein.

                                   ARTICLE IV

                                    OFFICERS

               Section 1. Principal Officers. The principal officers of the
Corporation shall be a Chairman, a Chief Executive Officer, a President, a
President of Technology, one or more Vice Presidents, a Treasurer and a
Secretary who shall have the duty, among other things, to record the proceedings
of the meetings of stockholders and directors in a book kept for that purpose.
The Corporation may also have such other principal officers, including one or
more Controllers, as the Board may in its discretion appoint. One person may
hold the offices and perform the duties of any two or more of said offices,
except that no one person shall hold the offices and perform the duties of
President and Secretary.

               Section 2. Election and Term of Office. The principal officers of
the Corporation shall be elected annually by the Board of Directors at the
annual meeting thereof. Each such officer shall hold office until his successor
is elected and qualified, or
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until his earlier death, resignation or removal. Any vacancy in any office shall
be filled in such manner as the Board of Directors shall determine.

               Section 3. Subordinate Officers. In addition to the principal
officers enumerated in Section 1 of this Article IV, the Corporation may have
one or more Assistant Treasurers, Assistant Secretaries and Assistant
Controllers and such other subordinate officers, agents and employees as the
Board of Directors may deem necessary, each of whom shall hold office for such
period as the Board of Directors may from time to time determine. The Board of
Directors may delegate to any principal officer the power to appoint and to
remove any such subordinate officers, agents or employees.

                  Section 4. Removal. Any officer may be removed, with or
without cause, at any time, by resolution adopted by the Board of Directors.

               Section 5. Resignations. Any officer may resign at any time by
giving written notice to the Board of Directors (or to a principal officer if
the Board of Directors has delegated to such principal officer the power to
appoint and to remove such officer). The resignation of any officer shall take
effect upon receipt of notice thereof or at such later time as shall be
specified in such notice; and unless otherwise specified therein, the acceptance
of such resignation shall not be necessary to make it effective.

               Section 6. Chairman. The Chairman shall preside at all meetings
of the Board of Directors and of shareholders, shall be responsible for the
observation by the Corporation of these by-laws and shall have such other duties
as shall be set forth in the resolution of the Board by which the appointment of
the Chairman is made.

               Section 7. Chief Executive Officer. The Chief Executive Officer
shall have general supervision over the business and operations of the
Corporation and may perform any act and execute any instrument for the conduct
of such business and operations. In the Chairman's absence, the Chief Executive
Officer shall preside at all meetings of the Board and of the shareholders.

               Section 8. Powers and Duties of Other Officers. The other
officers of the Corporation shall have such powers and perform such duties
incident to each of their respective offices and such other duties as may from
time to time be conferred upon or assigned to them by the Board of Directors.

                                    ARTICLE V

                               GENERAL PROVISIONS

               Section 1. Fixing the Record Date. (a) In order that the
Corporation may determine the stockholders entitled to notice of or to vote at
any meeting of stockholders or any adjournment thereof, the Board of Directors
may fix a record date, which record date shall not precede the date upon which
the resolution fixing the record date is adopted by the Board of Directors, and
which record date shall not be more than 60 nor less than
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10 days before the date of such meeting. If no record date is fixed by the Board
of Directors, the record date for determining stockholders entitled to notice of
or to vote at a meeting of stockholders shall be at the close of business on the
day preceding the day on which notice is given, or, if notice is waived, at the
close of business on the day preceding the day on which the meeting is held. A
determination of stockholders of record entitled to notice of or to vote at a
meeting of stockholders shall apply to any adjournment of the meeting; provided
that the Board of Directors may fix a new record date for the adjourned meeting.

               (b) In order that the Corporation may determine the stockholders
entitled to receive payment of any dividend or other distribution or allotment
of any rights or the stockholders entitled to exercise any rights in respect of
any change, conversion or exchange of stock, or for the purpose of any other
lawful action, the Board of Directors may fix a record date, which record date
shall not precede the date upon which the resolution fixing the record date is
adopted, and which record date shall be not more than 60 days prior to such
action. If no record date is fixed, the record date for determining stockholders
for any such purpose shall be at the close of business on the day on which the
Board of Directors adopts the resolution relating thereto.

               Section 2. Dividends. Subject to limitations contained in
Delaware Law and the certificate of incorporation, the Board of Directors may
declare and pay dividends upon the shares of capital stock of the Corporation,
which dividends may be paid in cash, in property or in shares of the capital
stock of the Corporation.

                  Section 3. Fiscal Year. The fiscal year of the Corporation
shall commence on January 1 and end on December 31 of each year.

               Section 4. Corporate Seal. The corporate seal shall have
inscribed thereon the name of the Corporation, the year of its organization and
the words "Corporate Seal, Delaware". The seal may be used by causing it or a
facsimile thereof to be impressed, affixed or otherwise reproduced.

               Section 5. Voting of Stock Owned by the Corporation. The Board of
Directors may authorize any person, on behalf of the Corporation, to attend,
vote at and grant proxies to be used at any meeting of stockholders of any
corporation (except this Corporation) in which the Corporation may hold stock.

               Section 6. Amendments. These bylaws or any of them, may be
altered, amended or repealed, or new bylaws may be made, by the Board of
Directors or by the affirmative vote of the holders of not less than 66 2/3% of
the total voting power of all outstanding securities of the Corporation then
entitled to vote generally in the election of directors, voting together as a
single class.