UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                 SCHEDULE 13G/A


                    Under the Securities Exchange Act of 1934
                               (Amendment No. 1)*



                       Terayon Communication Systems, Inc.
--------------------------------------------------------------------------------
                                (Name of Issuer)

                         Common Stock ($0.001 par value)
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    880775101
--------------------------------------------------------------------------------
                                 (CUSIP Number)

                                December 31, 2002
--------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)

                                Louise Guarneri
                           Credit Suisse First Boston
                                11 Madison Avenue
                            New York, New York 10010
                                 (212) 325-2000
--------------------------------------------------------------------------------
            (Name, Address and Telephone Number of Person Authorized
                     to Receive Notices and Communications)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

            |X| Rule 13d-1(b)
            |_| Rule 13d-1(c)
            |_| Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).





CUSIP No. 880775101
                                      13G/A                    Page 2 of 6 Pages


   1     NAME OF REPORTING PERSON
         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

         Credit Suisse First Boston, on behalf of the Credit Suisse First Boston
         business unit

   2     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                        (a)

                                                                        (b)   X

   3     SEC USE ONLY

   4     CITIZENSHIP OR PLACE OF ORGANIZATION
         SWITZERLAND

                              5    SOLE VOTING POWER

                                   -0-
         NUMBER OF
          SHARES              6    SHARED VOTING POWER
       BENEFICIALLY                (see Item 4(a))
         OWNED BY
           EACH                    5,421,603
         REPORTING
          PERSON              7    SOLE DISPOSITIVE POWER
           WITH
                                   -0-

                              8    SHARED DISPOSITIVE POWER
                                   (see Item 4(a))

                                   5,421,603

   9     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

         5,421,603

  10     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
         SHARES* |_|

  11     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

         7.4%

  12     TYPE OF REPORTING PERSON*

         BK, HC

                      *SEE INSTRUCTION BEFORE FILLING OUT!




Item 1.
     (a)       Name of Issuer:

               Terayon Communication Systems, Inc.

     (b)       Address of Issuer's Principal Executive Offices:

               4988 Great America Parkway, Santa Clara, CA  95054

Item 2.

     (a)       Name of Persons Filing:

               Credit Suisse First Boston, on behalf of the Credit Suisse First
               Boston business unit. See Schedule I.

     (b)       Address of Principal Business Office:

               Uetlibergstrasse 231, P.O. Box 900, CH-8070 Zurich, Switzerland

     (c)       Citizenship:

               Switzerland

     (d)       Title of Class of Securities:

               Common Stock

     (e)       CUSIP Number:

               880775101

Item 3. If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or
(c), check whether the person filing is a(n):

     (a)  [ ] Broker or Dealer registered under Section 15 of the Act
              (15 U.S.C. 78o)

     (b)  [X] Bank as defined in Section 3(a)(6) of the Act  (15 U.S.C. 78c)

     (c)  [ ] Insurance Company as defined in Section 3(a)(19) of the Act
              (15 U.S.C. 78c)

     (d)  [ ] Investment Company registered under Section 8 of the Investment
              Company Act (15 (U.S.C. 80a-8)

     (e)  [ ] Person registered as an investment adviser  under Section 203 of
              the Investment Advisers Act of 1940
              (15 U.S.C. 80b-3) or under the laws of any state.

     (f)  [ ] Employee Benefit Plan or Endowment Fund in accordance with
              Section 240.13d-1(b)(1)(ii)(F)

     (g)  [X] Parent Holding Company or Control Person in accordance with
              Section 240.13d-1(b)(ii)(G)

     (h)  [ ] Savings Association as defined in Section 3(b) of the Federal
              Deposit Insurance Act (12 U.S.C. 1813)

     (i)  [ ] Church Plan that is excluded from the definition of an investment
              company under Section 3(c)(14) of the Investment Company Act of
              1940 (15 U.S.C. 80a-3)

     (j)  [ ] Group in accordance with Section 240.13d-1(b)(1)(ii)(J)

Item 4.    Ownership

     (a)   Amount Beneficially Owned:

           See response to Item 9 on page 2.

     (b)   Percent of Class:

           See response to Item 11 on page 2.

     (c)   Number of shares as to which such person has:

             (i)  Sole power to vote  or to direct the vote:
                  See response to Item 5 on page 2.

            (ii)  Shared power to vote or to direct the vote:
                  See response to Item 6 on page 2.

           (iii)  Sole power to dispose or to direct the disposition of:
                  See response to Item 7 on page 2.

            (iv)  Shared power to direct the disposition of:
                  See response to Item 8 on page 2.

Item 5.    Ownership of Five Percent or Less of a Class

           If this statement is being filed to report the fact that as
           of the date hereof the X reporting person has ceased to be      [ ]
           the beneficial owner of more than five percent of the class
           of securities, check the following:

Item 6.    Ownership of More than Five Percent on Behalf of Another Person

           Not Applicable

Item 7.    Identification and Classification of the Subsidiary Which Acquired
           the Security Being Reported on by the Parent Holding Company

           See Schedule I.

Item 8.    Identification and Classification of Members of the Group

           Not Applicable

Item 9.    Notice of Dissolution of Group

           Not Applicable

Item 10.   Certification

           By signing  below I certify  that,  to the best of my  knowledge  and
           belief,  the securities  referred to above were acquired and are held
           in the ordinary  course of business and were not acquired and are not
           held for the purpose of or with the effect of changing or influencing
           the control of the issuer of the securities and were not acquired and
           are  not  held  in  connection  with  or  as  a  participant  in  any
           transaction having that purpose or effect.


                                    SIGNATURE

         After reasonable inquiry, and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

February 14, 2003


                                                     CREDIT SUISSE FIRST BOSTON,
                                                     acting solely on behalf of
                                                     the Credit Suisse First
                                                     Boston business unit

                                                     By: /s/ Louise Guarneri
                                                         -------------------
                                                     Name:  Louise Guarneri
                                                     Title: Director




                                   Schedule I


In accordance with Securities and Exchange Commission Release No. 34-39538
(January 12, 1998), this Schedule 13G is being filed by Credit Suisse First
Boston (the "Bank"), a Swiss bank, on behalf of itself and its subsidiaries, to
the extent that they constitute the Credit Suisse First Boston business unit
(the "CSFB business unit") excluding Asset Management (as defined below) (the
"Reporting Person"). The CSFB business unit is also comprised of an asset
management business principally conducted under the brand name Credit Suisse
Asset Management ("Asset Management"). The Reporting Person provides financial
advisory and capital raising services, sales and trading for users and suppliers
of capital around the world and invests in and manages private equity and
venture capital funds. Asset Management provides asset management and investment
advisory services to institutional, mutual fund and private investors worldwide.
The address of the Bank's principal business and office is Uetlibergstrasse 231,
P.O. Box 900, CH 8070 Zurich, Switzerland. The address of the Reporting Person's
principal business and office in the United States is Eleven Madison Avenue, New
York, New York 10010.

The ultimate parent company of the Bank is Credit Suisse Group ("CSG"), a
corporation formed under the laws of Switzerland. CSG is a global financial
services company with two distinct business units. In addition to the CSFB
business unit, CSG and its consolidated subsidiaries are comprised of the Credit
Suisse Financial Services business unit (the "Credit Suisse Financial Services
business unit"). CSG's business address is Paradeplatz 8, P.O. Box 1, CH 8070
Zurich, Switzerland.

CSG, for purposes of the federal securities laws, may be deemed ultimately to
control the Bank and the Reporting Person. CSG, its executive officers and
directors, and its direct and indirect subsidiaries (including Asset Management
and the Credit Suisse Financial Services business unit) may beneficially own
shares of the securities of the issuer to which this schedule relates (the
"Shares") and such Shares are not reported in this statement. CSG disclaims
beneficial ownership of Shares beneficially owned by its direct and indirect
subsidiaries, including the Reporting Person. The Reporting Person disclaims
beneficial ownership of Shares beneficially owned by CSG, Asset Management and
the Credit Suisse Financial Services business unit.