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                                    EXHIBIT 5

             OPINION AND CONSENT OF BROBECK, PHLEGER & HARRISON LLP


                                January 24, 2001


Cisco Systems, Inc.
170 West Tasman Drive
San Jose, California 95134-1706

            Re:  Cisco Systems, Inc. - Registration Statement for Offering of
                 1,392,884 Shares of Common Stock

Dear Ladies and Gentlemen:

               We have acted as counsel to Cisco Systems, Inc., a California
corporation (the "Company"), in connection with the registration on Form S-8
(the "Registration Statement") under the Securities Act of 1933, as amended, of
1,392,884 shares of the Company's common stock reserved for issuance under the
PixStream, Incorporated Key Employee Stock Option Plan as assumed by the Company
(the "PixStream Plan").

               This opinion is being furnished in accordance with the
requirements of Item 8 of Form S-8 and Item 601(b)(5)(i) of Regulation S-K.

               We have reviewed the Company's charter documents and the
corporate proceedings taken by the Company with respect to the assumption of
the PixStream Plan and the options outstanding thereunder in connection with the
Company's acquisition of PixStream, Incorporated. Based on such review, we are
of the opinion that, if, as and when the shares of the Company's common stock
are issued and sold (and the consideration therefor received) pursuant to the
provisions of option agreements for the outstanding options assumed under the
PixStream Plan and in accordance with the Registration Statement, such shares
will be duly authorized, legally issued, fully paid and nonassessable.

               We consent to the filing of this opinion letter as Exhibit 5 to
the Registration Statement.

               This opinion letter is rendered as of the date first written
above and we disclaim any obligation to advise you of facts, circumstances,
events or developments which hereafter may be brought to our attention and which
may alter, affect or modify the opinion expressed herein. Our opinion is
expressly limited to the matters set forth above and we render no opinion,
whether by implication or otherwise, as to any other matters relating to the
Company, the PixStream Plan or the shares of the Company's common stock issuable
thereunder.


                                        Very truly yours,

                                        /s/ BROBECK, PHLEGER & HARRISON LLP

                                        BROBECK, PHLEGER & HARRISON LLP



