
<PAGE>   1
    As filed with the Securities and Exchange Commission on October 8, 1999
                                                      Registration No. 333-_____

================================================================================
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                              ---------------------

                                    FORM S-8
                             REGISTRATION STATEMENT

                                      Under
                           The Securities Act of 1933

                              ---------------------

                               CISCO SYSTEMS, INC.
             (Exact name of registrant as specified in its charter)

                CALIFORNIA                          77-0059951
      (State or other jurisdiction       (IRS Employer Identification No.)
    of incorporation or organization)

             170 WEST TASMAN DRIVE, SAN JOSE, CALIFORNIA 95134-1706
               (Address of principal executive offices) (Zip Code)

                 STRATUMONE COMMUNICATIONS, INC. 1997 STOCK PLAN

                              ---------------------
                            (Full title of the Plan)

                                JOHN T. CHAMBERS
                 PRESIDENT, CHIEF EXECUTIVE OFFICER AND DIRECTOR
                               CISCO SYSTEMS, INC.
             170 WEST TASMAN DRIVE, SAN JOSE, CALIFORNIA 95134-1706
                     (Name and address of agent for service)

                                 (408) 526-4000
          (Telephone number, including area code, of agent for service)

                         CALCULATION OF REGISTRATION FEE
<TABLE>
<CAPTION>
=========================================================================================================================
                                                                   Proposed               Proposed
                Title of                                           Maximum                Maximum
               Securities                      Amount              Offering               Aggregate           Amount of
                  to be                        to be                Price                 Offering           Registration
               Registered                   Registered(1)         per Share (2)           Price (2)              Fee
               ----------                   -------------         -------------           ---------          ------------
<S>                                         <C>                       <C>                 <C>                   <C>
  StratumOne Communications, Inc. 1997
  Stock Plan
  Common Stock                              963,659 Shares            $6.24             $6,013,232.16         $1,672.00
=========================================================================================================================
</TABLE>


(1)      This Registration Statement shall also cover any additional shares of
         Registrant's Common Stock which become issuable under the StratumOne
         Communications, Inc. 1997 Stock Plan by reason of any stock dividend,
         stock split, recapitalization or other similar transaction effected
         without the Registrant's receipt of consideration which results in an
         increase in the number of the Registrant's outstanding shares of Common
         Stock.

(2)      Calculated solely for purposes of this offering under Rule 457(h) of
         the Securities Act of 1933, as amended, on the basis of the weighted
         average exercise price of the outstanding options.



<PAGE>   2




                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference

                  Cisco Systems, Inc. (the "Registrant") hereby incorporates by
reference into this Registration Statement the following documents previously
filed with the Securities and Exchange Commission (the "Commission"):

         (a)      The Registrant's Annual Report on Form 10-K for the fiscal
                  year ended July 31, 1999 filed with the Commission on
                  September 28, 1999, pursuant to Section 13 of the Securities
                  Exchange Act of 1934, as amended (the "1934 Act");

         (b)      The Registrant's Current Reports on Form 8-K filed with the
                  Commission on August 13, 1999, as amended on Form 8-K/A on
                  August 13, 1999, August 26, 1999 and September 27, 1999;

         (c)      The Registrant's Registration Statement No. 000-18225 on Form
                  8-A filed with the Commission on January 11, 1990, together
                  with Amendment No. 1 on Form 8-A/A filed with the Commission
                  on February 15, 1990, and including any other amendments or
                  reports filed for the purpose of updating such description, in
                  which there is described the terms, rights and provisions
                  applicable to the Registrant's Common Stock, and;

         (d)      The Registrant's Registration Statement No. 000-18225 on Form
                  8-A filed with the Commission on June 11, 1998, including any
                  amendments or reports filed for the purpose of updating such
                  description, in which there is described the terms, rights and
                  provisions applicable to the Registrant's Preferred Stock
                  Purchase Rights.

                  All reports and definitive proxy or information statements
filed pursuant to Section 13(a), 13(c), 14 or 15(d) of the 1934 Act after the
date of this Registration Statement and prior to the filing of a post-effective
amendment which indicates that all securities offered hereby have been sold or
which de-registers all securities then remaining unsold shall be deemed to be
incorporated by reference into this Registration Statement and to be a part
hereof from the date of filing of such documents. Any statement contained in a
document incorporated or deemed to be incorporated by reference herein shall be
deemed to be modified or superseded for purposes of this Registration Statement
to the extent that a statement contained herein or in any subsequently filed
document which also is deemed to be incorporated by reference herein modifies or
supersedes such statement. Any such statement so modified or superseded shall
not be deemed, except as so modified or superseded, to constitute a part of this
Registration Statement.

Item 4.  Description of Securities

                  Not Applicable.

Item 5.  Interests of Named Experts and Counsel

                  Not Applicable.

Item 6.  Indemnification of Directors and Officers

                  Section 317 of the California Corporations Code authorizes a
court to award, or a corporation's Board of Directors to grant indemnity to
directors and officers in terms sufficiently broad to permit indemnification
(including reimbursement of expenses incurred) under certain circumstances for
liabilities arising under the Securities Act of 1933, as amended, (the "1933
Act"). The Registrant's Restated Articles of Incorporation, as amended, and
Amended and Restated Bylaws provide for indemnification of its directors,
officers, employees and other agents to the maximum extent permitted by the
California Corporations Code. In addition, the Registrant has entered into
Indemnification Agreements with each of its directors and officers.



                                      II-1
<PAGE>   3

Item 7.  Exemption from Registration Claimed

                  Not Applicable.

Item 8.  Exhibits

Exhibit Number             Exhibit

   4                       Instruments Defining the Rights of Stockholders.
                           Reference is made to Registrant's Registration
                           Statements No. 000-18225 on Form 8-A, together with
                           the amendments and exhibits thereto, which are
                           incorporated herein by reference pursuant to Items
                           3(c) and 3(d).

   5                       Opinion and consent of Brobeck, Phleger & Harrison
                           LLP.

   23.1                    Consent of PricewaterhouseCoopers LLP, Independent
                           Accountants.

   23.2                    Consent of Brobeck, Phleger & Harrison LLP is
                           contained in Exhibit 5.

   24                      Power of Attorney. Reference is made to page II-4 of
                           this Registration Statement.

   99.1                    StratumOne Communications, Inc. 1997 Stock Plan.

   99.2                    StratumOne Communications, Inc. 1997 Stock Plan-Form
                           of Stock Option Agreement.

   99.3                    StratumOne Communications, Inc. 1997 Stock Plan-Form
                           of Stock Option Agreement-Early Exercise.

   99.4                    StratumOne Communications, Inc. 1997 Stock Plan-Form
                           of Restricted Stock Purchase Agreement.

   99.5                    Form of Stock Option Assumption Agreement

Item 9.  Undertakings

                  A. The undersigned Registrant hereby undertakes: (1) to file,
during any period in which offers or sales are being made, a post-effective
amendment to this Registration Statement: (i) to include any prospectus required
by Section 10(a)(3) of the 1933 Act, (ii) to reflect in the prospectus any facts
or events arising after the effective date of this Registration Statement (or
the most recent post-effective amendment thereof) which, individually or in the
aggregate, represent a fundamental change in the information set forth in this
Registration Statement and (iii) to include any material information with
respect to the plan of distribution not previously disclosed in this
Registration Statement or any material change to such information in this
Registration Statement; provided, however, that clauses (1)(i) and (1)(ii) shall
not apply if the information required to be included in a post-effective
amendment by those clauses is contained in periodic reports filed by the
Registrant pursuant to Section 13 or Section 15(d) of the 1934 Act that are
incorporated by reference into this Registration Statement; (2) that for the
purpose of determining any liability under the 1933 Act each such post-effective
amendment shall be deemed to be a new registration statement relating to the
securities offered therein and the offering of such securities at that time
shall be deemed to be the initial bona fide offering thereof; and (3) to remove
from registration by means of a post-effective amendment any of the securities
being registered which remain unsold at the termination of the StratumOne
Communications, Inc. 1997 Stock Plan.

                  B. The undersigned Registrant hereby undertakes that, for
purposes of determining any liability under the 1933 Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
1934 Act that is incorporated by reference into this Registration Statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.

                  C. Insofar as indemnification for liabilities arising under
the 1933 Act may be permitted to directors, officers or controlling persons of
the Registrant pursuant to the indemnification provisions summarized in Item 6
or otherwise, the Registrant has been advised that, in the opinion of the
Commission, such indemnification is against public policy as expressed in the
1933 Act and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by the
Registrant of expenses incurred or paid by a director, officer, or controlling
person of the Registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, the Registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the 1933 Act and
will be governed by the final adjudication of such issue.



                                      II-2
<PAGE>   4




                                   SIGNATURES

                  Pursuant to the requirements of the Securities Act of 1933, as
amended, the Registrant certifies that it has reasonable grounds to believe that
it meets all of the requirements for filing on Form S-8, and has duly caused
this Registration Statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of San Jose, State of California on this
8th day of October, 1999.

                               CISCO SYSTEMS, INC.


                               By: /s/John T. Chambers
                                   -------------------------------------
                                   John T. Chambers
                                   President, Chief Executive Officer
                                   and Director

                                POWER OF ATTORNEY

                  KNOW ALL PERSONS BY THESE PRESENTS, that each person whose
signature appears below constitutes and appoints John T. Chambers and Larry R.
Carter, and each of them, as such person's true and lawful attorneys-in-fact and
agents, with full power of substitution and resubstitution, for such person and
in such person's name, place and stead, in any and all capacities, to sign any
and all amendments (including post-effective amendments) to this Registration
Statement, and to file same, with all exhibits thereto, and other documents in
connection therewith, with the Securities and Exchange Commission, granting unto
said attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be done
in connection therewith, as fully to all intents and purposes as such person
might or could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them, or their or his or her
substitutes, may lawfully do or cause to be done by virtue thereof.

                  Pursuant to the requirements of the Securities Act of 1933, as
amended, this Registration Statement has been signed below by the following
persons on behalf of the Registrant and in the capacities and on the dates
indicated:

<TABLE>
<CAPTION>

Signature                                       Title                                              Date
<S>                                             <C>                                           <C>
/s/John T. Chambers                             President, Chief Executive                    October 8, 1999
----------------------------------------        Officer and Director
John T. Chambers                                (Principal Executive Officer)



/s/Larry R. Carter                              Senior Vice President, Finance                October 8, 1999
----------------------------------------        and Administration, Chief Financial
Larry R. Carter                                 Officer and Secretary
                                                (Principal Financial and Accounting
                                                Officer)


/s/John P. Morgridge                            Chairman of the Board and                     October 8, 1999
----------------------------------------        Director
John P. Morgridge


/s/Donald T. Valentine                          Vice Chairman of the Board and                October 8, 1999
----------------------------------------        Director
Donald T. Valentine
</TABLE>



                                      II-3
<PAGE>   5

<TABLE>
<CAPTION>

<S>                                             <C>                                           <C>
/s/James F. Gibbons                             Director                                      October 8, 1999
----------------------------------------
James F. Gibbons


/s/Robert L. Puette                             Director                                      October 8, 1999
----------------------------------------
Robert L. Puette


                                                Director
----------------------------------------
Masayoshi Son


/s/Steven M. West                               Director                                       October 8, 1999
----------------------------------------
Steven M. West


/s/Edward R. Kozel                              Director                                      October 8, 1999
----------------------------------------
Edward R. Kozel


                                                Director
----------------------------------------
Carol A. Bartz


/s/James C. Morgan                              Director                                      October 8, 1999
----------------------------------------
James C. Morgan


/s/Mary Cirillo                                 Director                                      October 8, 1999
----------------------------------------
Mary Cirillo


/s/Arun Sarin                                   Director                                      October 8, 1999
----------------------------------------
Arun Sarin
</TABLE>



                                      II-4
<PAGE>   6



                                  EXHIBIT INDEX

Item 8.  Exhibits

Exhibit Number             Exhibit

   4                       Instruments Defining the Rights of Stockholders.
                           Reference is made to Registrant's Registration
                           Statements No. 000-18225 on Form 8-A, together with
                           the amendments and exhibits thereto, which are
                           incorporated herein by reference pursuant to Items
                           3(c) and 3(d).

   5                       Opinion and consent of Brobeck, Phleger & Harrison
                           LLP.

   23.1                    Consent of PricewaterhouseCoopers LLP, Independent
                           Accountants.

   23.2                    Consent of Brobeck, Phleger & Harrison LLP is
                           contained in Exhibit 5.

   24                      Power of Attorney. Reference is made to page II-4 of
                           this Registration Statement.

   99.1                    StratumOne Communications, Inc. 1997 Stock Plan.

   99.2                    StratumOne Communications, Inc. 1997 Stock Plan-Form
                           of Stock Option Agreement.

   99.3                    StratumOne Communications, Inc. 1997 Stock Plan-Form
                           of Stock Option Agreement-Early Exercise.

   99.4                    StratumOne Communications, Inc. 1997 Stock Plan-Form
                           of Restricted Stock Purchase Agreement.

   99.5                    Form of Stock Option Assumption Agreement



