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                                                                     EXHIBIT 2.1

                               AGREEMENT OF MERGER

                                       OF

                                    ACQUIROR

                                       AND

                                     TARGET


        This Agreement of Merger, dated as of the 2nd day of June, 1999 ("Merger
Agreement"), between Cisco Systems, Inc., a California corporation ("Acquiror"),
and Amteva Technologies, Inc., a Virginia corporation ("Target").

                                    RECITALS

        A.      Target was incorporated in the State of Virginia on August 16,
1995 and on the date hereof has outstanding 5,386,958 shares of Common Stock
("Target Common Stock"), and 1,484,000 shares of Series A Preferred Stock,
404,727 shares of Series B Preferred Stock and 2,253,828 shares of Series C
Preferred Stock (collectively the "Target Preferred Stock," and together with
the shares of Target Common Stock, the "Target Shares").

        B.      Acquiror and Target have entered into an Agreement and Plan of
Reorganization (the "Agreement and Plan of Reorganization") providing for
certain representations, warranties, covenants and agreements in connection with
the transactions contemplated hereby. This Merger Agreement and the Agreement
and Plan of Reorganization are intended to be construed together to effectuate
their purpose.

        C.      The Boards of Directors of Target and Acquiror deem it advisable
and in their mutual best interests and in the best interests of the shareholder
of Target, that Target be acquired by Acquiror through a merger ("Merger") of
Target with and into Acquiror.

        D.      The Boards of Directors of Acquiror and Target and the
shareholders of Target have approved the Merger.

                                   AGREEMENTS

                The parties hereto hereby agree as follows:

        1.      Target shall be merged with and into Acquiror, and Acquiror
shall be the surviving corporation.

        2.      The Merger shall become effective at such time (the "Effective
Time") as this Merger Agreement and the officers' certificate of Target is filed
with the Secretary of State of the State of California pursuant to Section 1103
of the Corporations Code of the State of California.

        3.      At the Effective Time of the Merger (i) all shares of Target
Common Stock that are owned directly or indirectly by Target shall be cancelled,
and no securities of Acquiror or other consideration shall be delivered in
exchange therefor, (ii) each of the issued and outstanding shares of Target
Common Stock, Target Series A Preferred Stock and Target Series B and Series C
Preferred Stock (other than shares, if any, held by persons who have not voted
such shares for approval of the Merger and with respect to which such persons
shall become entitled to exercise dissenters' rights in accordance with the
Corporations Code of the State of California, referred to hereinafter as
"Dissenting Shares") shall be converted automatically into and exchanged for
0.104902, 0.135063 and 0.160197, respectively of a share of Acquiror Common
Stock; provided, however, that no more than 1,518,164 shares of Common Stock of
Acquiror shall be issued in such exchange (including Acquiror Common Stock
reserved



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for issuance upon exercise of Target options assumed by Acquiror). Those shares
of Acquiror Common Stock to be issued as a result of the Merger are referred to
herein as the "Acquiror Shares".

        4.      Any Dissenting Shares shall not be converted into Acquiror
Common Stock but shall be converted into the right to receive such consideration
as may be determined to be due with respect to such Dissenting Shares pursuant
to the law of the State of Virginia. If after the Effective Time any Dissenting
Shares shall lose their status as Dissenting Shares, then as of the occurrence
of the event which causes the loss of such status, such shares shall be
converted into Acquiror Common Stock in accordance with Section 3.

        5.      Notwithstanding any other term or provision hereof but subject
to the proviso in the second sentence of Section 3, no fractional shares of
Acquiror Common Stock shall be issued, but in lieu thereof each holder of Target
Shares who would otherwise, but for rounding as provided herein, be entitled to
receive a fraction of a share of Acquiror Common Stock shall receive from
Acquiror an amount of cash equal to the per share market value of Acquiror
Common Stock (deemed to be $111.71) multiplied by the fraction of a share of
Acquiror Common Stock to which such holder would otherwise be entitled. The
fractional share interests of each Target shareholder shall be aggregated, so
that no Target shareholder shall receive cash in an amount greater than the
value of one full share of Acquiror Common Stock.

        6.      The conversion of Target Common Stock and Target Preferred Stock
into Acquiror Common Stock as provided by this Merger Agreement shall occur
automatically at the Effective Time of the Merger without action by the holders
thereof. Each holder of Target Common Stock and Target Preferred Stock shall
thereupon be entitled to receive shares of Acquiror Common Stock in accordance
with the Agreement and Plan of Reorganization.

        7.      At the Effective Time of the Merger, the separate existence of
Target shall cease, and Acquiror shall succeed, without other transfer, to all
of the rights and properties of Target and shall be subject to all the debts and
liabilities thereof in the same manner as if Acquiror had itself incurred them.
All rights of creditors and all liens upon the property of each corporation
shall be preserved unimpaired, provided that such liens upon property of Target
shall be limited to the property affected thereby immediately prior to the
Effective Time of the Merger.

        8.      This Merger Agreement is intended as a plan of reorganization
within the meaning of Section 368 of the Internal Revenue Code of 1986, as
amended.

                9.      (a)     The Amended and Restated Articles of
Incorporation of Acquiror in effect immediately prior to the Effective Time
shall be the Amended and Restated Articles of Incorporation of the Surviving
Corporation unless and until thereafter amended.

                        (b)     The Bylaws of Acquiror in effect immediately
prior to the Effective Time shall be the Bylaws of the Surviving Corporation
unless and until amended or repealed as provided by applicable law, the Articles
of Incorporation of the Surviving Corporation and such Bylaws.

                        (c)     The directors and officers of Acquiror
immediately prior to the Effective Time shall be the directors and officers of
the Surviving Corporation.

                10.     (a)     Notwithstanding the approval of this Merger
Agreement by the shareholders of Target, this Merger Agreement shall terminate
forthwith in the event that the Agreement and Plan of Reorganization shall be
terminated as therein provided.

                        (b)     In the event of the termination of this Merger
Agreement as provided above, this Merger Agreement shall forthwith become void
and there shall be no liability on the part of Target or Acquiror or their
respective officers or directors, except as otherwise provided in the Agreement
and Plan of Reorganization.

                        (c)     This Merger Agreement may be signed in one or
more counterparts, each of which shall be deemed an original and all of which
shall constitute one agreement.


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                        (d)     This Merger Agreement may be amended by the
parties hereto any time before or after approval hereof by the shareholders of
Target, but, after such approval, no amendments shall be made which by law
require the further approval of such shareholders without obtaining such
approval. This Merger Agreement may not be amended except by an instrument in
writing signed on behalf of each of the parties hereto.



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                IN WITNESS WHEREOF, the parties have executed this Merger
Agreement as of the date first written above.


                                        ACQUIROR



                                        By: /s/ John T. Chambers
                                           -------------------------------------
                                           John T. Chambers, President


                                        By: /s/ Larry R. Carter
                                           -------------------------------------
                                           Larry R. Carter, Secretary


                                        TARGET



                                        By: /s/ L. Dean Dodrill
                                           -------------------------------------
                                           L. Dean Dodrill, President


                                        By: /s/ Robert M. Tuck
                                           -------------------------------------
                                           Robert M. Tuck, Secretary



