<PAGE>   1

     As filed with the Securities and Exchange Commission February 8, 2000
                                                      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)


                       INTERNET ENGINEERING GROUP, L.L.C.

                     1999 EQUITY OPTION/EQUITY ISSUANCE 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)

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

<TABLE>
<CAPTION>
                                           CALCULATION OF REGISTRATION FEE
==============================================================================================================================
                                                                     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>
Internet Engineering Group, L.L.C.          599,126 Shares            $28.61            $17,140,994.86          4,525.23
   1999 Equity Option/Equity
   Issuance Plan
Common Stock (par value $0.01)
==============================================================================================================================
</TABLE>

(1)      This Registration Statement shall also cover any additional shares of
         Registrant's Common Stock which become issuable under the Internet
         Engineering Group, L.L.C. 1999 Equity Option/Equity Issuance 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, as amended on Form 10-K405/A filed with
                  the Commission on February 3, 2000, 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 filed
                  with the Commission on August 13, 1999, August 26, 1999,
                  September 27, 1999, October 20, 1999, November 4, 1999,
                  November 17, 1999, December 15, 1999, as amended on Form 8-K/A
                  filed with the Commission on February 3, 2000, and December
                  22, 1999;

         (c)      The Registrant's Quarterly Report on Form 10-Q for the fiscal
                  quarter ended October 30, 1999, filed with the Commission on
                  December 14, 1999, as amended on Form 10-Q/A filed with the
                  Commission on February 3, 2000;

         (d)      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;

         (e)      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



                                      II-1
<PAGE>   3

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.

Item 7.  Exemption from Registration Claimed

         Not Applicable.

Item 8.  Exhibits

<TABLE>
<CAPTION>
Exhibit Number      Exhibit
--------------      -------
<S>                 <C>
   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(d) and 3(e).
   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-3 of this
                    Registration Statement.
   99.1             Internet Engineering Group, L.L.C. 1999 Equity Option/Equity
                    Issuance Plan.
   99.2             Internet Engineering Group, L.L.C.- Form of Equity Option
                    Agreement.
   99.3             Form of Option Assumption Agreement.
</TABLE>

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 Internet
Engineering Group, L.L.C. 1999 Equity Option/Equity Issuance 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 February, 2000.


                             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                   February 8, 2000
---------------------------------      Officer and Director
John T. Chambers                       (Principal Executive Officer)


/s/ Larry R. Carter                    Senior Vice President, Finance               February 8, 2000
---------------------------------      and Administration, Chief Financial
Larry R. Carter                        Officer and Secretary
                                       (Principal Financial and Accounting
                                       Officer)


/s/  John P. Morgridge                 Chairman of the Board and                    February 8, 2000
---------------------------------      Director
John P. Morgridge


/s/  Donald T. Valentine               Vice Chairman of the Board and               February 8, 2000
---------------------------------      Director
Donald T. Valentine
</TABLE>



                                      II-3
<PAGE>   5

<TABLE>
<S>                                    <C>                                          <C>
/s/  James F. Gibbons                  Director                                     February 8, 2000
---------------------------------
James F. Gibbons


/s/  Steven M. West                    Director                                     February 8, 2000
---------------------------------
Steven M. West


/s/ Edward R. Kozel                    Director                                     February 8, 2000
---------------------------------
Edward R. Kozel


/s/   Carol A. Bartz                   Director                                     February 8, 2000
---------------------------------
Carol A. Bartz


/s/ James C. Morgan                    Director                                     February 8, 2000
---------------------------------
James C. Morgan


/s/  Mary Cirillo                      Director                                     February 8, 2000
---------------------------------
Mary Cirillo


/s/  Arun Sarin                        Director                                     February 8, 2000
---------------------------------
Arun Sarin
</TABLE>



                                      II-4
<PAGE>   6


                                 EXHIBIT INDEX



<TABLE>
<CAPTION>
Exhibit Number      Exhibit
--------------      -------
<S>                 <C>
   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(d) and 3(e).
   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-3 of this
                    Registration Statement.
   99.1             Internet Engineering Group, L.L.C. 1999 Equity Option/Equity
                    Issuance Plan.
   99.2             Internet Engineering Group, L.L.C.- Form of Equity Option
                    Agreement.
   99.3             Form of Option Assumption Agreement.
</TABLE>
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 19011}]
{"company-data": {"conformed-name": "CISCO SYSTEMS INC", "cik": "0000858877", "assigned-sic": "3576", "irs-number": "770059951", "state-of-incorporation": "CA", "fiscal-year-end": "0731"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-96367", "film-number": "526637"}, "business-address": {"street1": "170 WEST TASMAN DRIVE", "city": "SAN JOSE", "state": "CA", "zip": "95134-1706", "phone": "4085264000"}, "mail-address": {"street1": "225 WEST TASMAN DRIVE", "city": "SAN JOSE", "state": "CA", "zip": "95134-1706"}}
1

     As filed with the Securities and Exchange Commission February 8, 2000
                                                      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)

                       INTERNET ENGINEERING GROUP, L.L.C.

                     1999 EQUITY OPTION/EQUITY ISSUANCE 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
==============================================================================================================================
                                                                     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
------------------------------------------------------------------------------------------------------------------------------
Internet Engineering Group, L.L.C.          599,126 Shares            $28.61            $17,140,994.86          4,525.23
   1999 Equity Option/Equity
   Issuance Plan
Common Stock (par value $0.01)
==============================================================================================================================
(1)      This Registration Statement shall also cover any additional shares of
         Registrant's Common Stock which become issuable under the Internet
         Engineering Group, L.L.C. 1999 Equity Option/Equity Issuance 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.
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, as amended on Form 10-K405/A filed with
                  the Commission on February 3, 2000, 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 filed
                  with the Commission on August 13, 1999, August 26, 1999,
                  September 27, 1999, October 20, 1999, November 4, 1999,
                  November 17, 1999, December 15, 1999, as amended on Form 8-K/A
                  filed with the Commission on February 3, 2000, and December
                  22, 1999;

         (c)      The Registrant's Quarterly Report on Form 10-Q for the fiscal
                  quarter ended October 30, 1999, filed with the Commission on
                  December 14, 1999, as amended on Form 10-Q/A filed with the
                  Commission on February 3, 2000;

         (d)      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;

         (e)      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

                                      II-1
3

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.

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(d) and 3(e).
   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-3 of this
                    Registration Statement.
   99.1             Internet Engineering Group, L.L.C. 1999 Equity Option/Equity
                    Issuance Plan.
   99.2             Internet Engineering Group, L.L.C.- Form of Equity Option
                    Agreement.
   99.3             Form of 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 Internet
Engineering Group, L.L.C. 1999 Equity Option/Equity Issuance 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
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 February, 2000.

                             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:
Signature                              Title                                              Date
---------                              -----                                              ----
/s/ John T. Chambers                   President, Chief Executive                   February 8, 2000
---------------------------------      Officer and Director
John T. Chambers                       (Principal Executive Officer)

/s/ Larry R. Carter                    Senior Vice President, Finance               February 8, 2000
---------------------------------      and Administration, Chief Financial
Larry R. Carter                        Officer and Secretary
                                       (Principal Financial and Accounting
                                       Officer)

/s/  John P. Morgridge                 Chairman of the Board and                    February 8, 2000
---------------------------------      Director
John P. Morgridge

/s/  Donald T. Valentine               Vice Chairman of the Board and               February 8, 2000
---------------------------------      Director
Donald T. Valentine
II-3
5
/s/  James F. Gibbons                  Director                                     February 8, 2000
---------------------------------
James F. Gibbons

/s/  Steven M. West                    Director                                     February 8, 2000
---------------------------------
Steven M. West

/s/ Edward R. Kozel                    Director                                     February 8, 2000
---------------------------------
Edward R. Kozel

/s/   Carol A. Bartz                   Director                                     February 8, 2000
---------------------------------
Carol A. Bartz

/s/ James C. Morgan                    Director                                     February 8, 2000
---------------------------------
James C. Morgan

/s/  Mary Cirillo                      Director                                     February 8, 2000
---------------------------------
Mary Cirillo

/s/  Arun Sarin                        Director                                     February 8, 2000
---------------------------------
Arun Sarin
II-4
6

                                 EXHIBIT INDEX
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(d) and 3(e).
   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-3 of this
                    Registration Statement.
   99.1             Internet Engineering Group, L.L.C. 1999 Equity Option/Equity
                    Issuance Plan.
   99.2             Internet Engineering Group, L.L.C.- Form of Equity Option
                    Agreement.
   99.3             Form of Option Assumption Agreement.