EXHIBIT (A)5
                          Offer to Purchase for Cash

                    All Outstanding Shares of Common Stock

                                      of

                              RAMP NETWORKS, INC.

                                      at

                          $5.80 Net Per Share in Cash

                                      to

                          BLACKBIRD ACQUISITION, INC.
                      a direct wholly owned subsidiary of

                               NOKIA CORPORATION


  THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK
  CITY TIME, ON TUESDAY, JANUARY 16, 2001 UNLESS THE OFFER IS EXTENDED.


                                                              December 15, 2000

To Our Clients:

   Enclosed for your consideration are an Offer to Purchase, dated December
15, 2000 (the "Offer to Purchase"), and a related Letter of Transmittal
(which, together with the Offer to Purchase and any amendments or supplements
thereto, collectively constitute the "Offer") in connection with the offer by
BLACKBIRD ACQUISITION, INC., a Delaware corporation ("Purchaser") and a direct
wholly owned subsidiary of NOKIA CORPORATION, a public limited liability
company incorporated under the laws of the Republic of Finland ("Parent"), to
purchase all the shares of common stock, par value $0.001 per share ("Shares")
of RAMP NETWORKS, INC., a Delaware corporation (the "Company"), that are
issued and outstanding for $5.80 per share (such amount being the "Per Share
Amount"), net to the seller in cash, upon the terms and subject to the
conditions set forth in the Offer to Purchase.

   We are (or our nominee is) the holder of record of Shares held for your
account. A tender of such Shares can be made only by us as the holder of
record and pursuant to your instructions. The endorsed Letter of Transmittal
is furnished to you for your information only and cannot be used by you to
tender Shares held by us for your account.

   We request instructions as to whether you wish to have us tender on your
behalf any or all Shares held by us for your account, upon the terms and
subject to the conditions set forth in the Offer.

   Your attention is invited to the following:

  1. The tender price is $5.80 per Share, net to you in cash (subject to
     applicable withholding taxes), without interest thereon.

  2. The Offer is being made for all outstanding Shares.

  3. The Board of Directors of the Company has unanimously determined that
     the Merger Agreement and the transactions contemplated thereby,
     including each of the Offer and the Merger, are fair to, and in the best
     interests of, the holders of Shares, has approved the Merger Agreement
     and the transactions contemplated thereby, including each of the Offer
     and the Merger, and has recommended that holders of Shares accept the
     Offer and tender their Shares pursuant to the Offer.


  4. The Offer and withdrawal rights will expire at 12:00 Midnight, New York
     City time, Tuesday, January 16, 2001, unless the Offer is extended.

  5. The Offer is conditioned upon, among other things, (i) there having been
     validly tendered and not withdrawn prior to the expiration of the Offer
     at least the number of Shares that shall constitute 51% of the then
     outstanding shares on a fully diluted basis (including, without
     limitation, all Shares issuable upon the conversion of any convertible
     securities or upon the exercise of any vested options, warrants, or
     rights), and (ii) any applicable waiting period under the Hart-Scott-
     Rodino Antitrust Improvements Act of 1976, as amended, having expired or
     been terminated prior to the expiration of the Offer.

  6. Tendering stockholders will not be obligated to pay brokerage fees or
     commissions or, except as otherwise provided in Instruction 6 of the
     Letter of Transmittal, stock transfer taxes with respect to the purchase
     of Shares by Purchaser pursuant to the Offer.

   If you wish to have us tender any or all of your Shares, please so instruct
us by completing, executing and returning to us the instruction form contained
in this letter. An envelope in which to return your instructions to us is
enclosed. If you authorize the tender of your Shares, all such Shares will be
tendered unless otherwise specified in your instructions. Your instructions
should be forwarded to us in ample time to permit us to submit a tender on
your behalf prior to the expiration of the Offer.

   The Offer is being made solely by the Offer to Purchase and the related
Letter of Transmittal and is being made to holders of Shares. Purchaser is not
aware of any jurisdiction where the making of the Offer is prohibited by any
administrative or judicial action pursuant to any valid state statute. If
Purchaser becomes aware of any valid state statute prohibiting the making of
the Offer or the acceptance of Shares pursuant thereto, Purchaser will make a
good faith effort to comply with such state statute. If, after such good faith
effort, Purchaser cannot comply with such state statute, the Offer will not be
made to (nor will tenders be accepted from or on behalf of) the holders of
Shares in such state. In any jurisdiction where the securities, blue sky or
other laws require the Offer to be made by a licensed broker or dealer, the
Offer shall be deemed to be made on behalf of Purchaser by one or more
registered brokers or dealers licensed under the laws of such jurisdiction.

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          Instructions with Respect to the Offer to Purchase for Cash

                            All Outstanding Shares

                                      of

                              RAMP NETWORKS, INC.

   The undersigned acknowledge(s) receipt of your letter and the enclosed
Offer to Purchase, dated December 15, 2000, and the related Letter of
Transmittal (which, together with the Offer to Purchaser and any amendments or
supplements thereto, collectively constitute the "Offer") in connection with
the offer by BLACKBIRD ACQUISITION, INC., a Delaware corporation and a direct
wholly owned subsidiary of NOKIA CORPORATION, a public limited liability
company incorporated under the laws of the Republic of Finland, to purchase
all the shares of common stock, par value $0.001 per share ("Shares"), of RAMP
NETWORKS, INC., a Delaware corporation, that are issued and outstanding, at a
price of $5.80 per share, net to the seller in cash (subject to applicable
withholding taxes), without interest thereon.

   This will instruct you to tender the number of Shares indicated below (or,
if no number is indicated below, all Shares) that are held by you for the
account of the undersigned, upon the terms and subject to the conditions set
forth in the Offer.

    NUMBER OF SHARES TO BE                              SIGN HERE
           TENDERED:                      -------------------------------------

                                          -------------------------------------
SHARES/1/: ____________________                       Signature(s)

                                          -------------------------------------
                                          -------------------------------------
                                              Please type or print names(s)
                                          -------------------------------------
                                          -------------------------------------
                                          -------------------------------------
                                              Please type or print address
                                          -------------------------------------
                                             Area Code and Telephone Number
                                          -------------------------------------
                                            Taxpayer Identification or Social
                                                     Security Number


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/1/Unless otherwise indicated, it will be assumed that all of your Shares held
  by us for your account are to be tendered.

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