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                                                                    EXHIBIT 23.5
 
                        CONSENT OF DAIN RAUSCHER WESSELS
 
     We hereby consent to the use of our opinion dated April 12, 1999 as
Appendix D to the Proxy Statement/Prospectus included in the Registration
Statement on Form S-4 relating to the merger of a wholly-owned subsidiary of
Cisco Systems, Inc. with and into GeoTel Communications Corporation and to the
references to our firm name in such Proxy Statement/Prospectus in each place it
appears therein. In giving such consent, we do not admit that we come within the
category of persons whose consent is required under Section 7 of the Securities
Act of 1933, as amended, or the rules and regulations of the Securities and
Exchange Commission thereunder, nor do we admit that we are experts with respect
to any part of such Registration Statement within the meaning of the term
"experts" as used in the Securities Act of 1933, as amended, or the rules and
regulations of the Securities and Exchange Commission thereunder.
 
                                               /s/ DAIN RAUSCHER WESSELS
                                          --------------------------------------
                                          DAIN RAUSCHER WESSELS,
                                          A division of Dain Rauscher
                                          Corporation
 
May 13, 1999
