Exhibit 10.24.2


           SECOND LOAN MODIFICATION TO THE LOAN AND SECURITY AGREEMENT

         This Second Loan Modification Agreement to the Loan and Security
Agreement (this "Loan Modification Agreement') is entered into as of December
20, 2001, by and between SILICON VALLEY BANK, a California-chartered bank, with
its principal place of business at 3003 Tasman Drive, Santa Clara, California
95054 and with a loan production office located at One Newton Executive Park,
Suite 200, 2221 Washington Street, Newton, Massachusetts 02462, doing business
under the name "Silicon Valley East" ("Bank") and (i) VISUAL NETWORKS, INC., a
Delaware corporation ("Visual"), (ii) VISUAL NETWORKS OPERATIONS, INC., a
Delaware corporation ("VNO"), (iii) VISUAL NETWORKS INVESTMENTS, INC., a
California corporation ("VNI"), (iv) VISUAL NETWORKS TECHNOLOGIES, INC., a
California corporation ("VNT"), (v) VISUAL NETWORKS OF TEXAS, L.P., a Texas
limited partnership ("Visual Texas"), (vi) VISUAL NETWORKS INSURANCE, INC., a
Vermont corporation ("Visual Insurance"), (vii) INVERSE NETWORK TECHNOLOGY, a
California corporation ("INT"), and (viii) AVESTA TECHNOLOGIES, INC., a Delaware
corporation ("Avesta") (hereinafter, Visual, VNO, VNI, VNT, Visual Texas, Visual
Insurance, INT, and Avesta are referred to jointly, severally and collectively
as the "Borrower" or "Borrowers" and Visual, as agent for each of Visual, VNO,
VNI, VNT, Visual Texas, Visual Insurance, INT, and Avesta is sometimes referred
to hereinafter in such capacity as the "Agent").

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other
indebtedness and obligations which may be owing by Borrower to Bank, Borrower is
indebted to Bank pursuant to a loan arrangement dated as of February 28, 2001,
evidenced by, among other documents, (i) a certain Loan and Security Agreement
dated as of February 28, 2001, between Borrower and Bank, as amended by a
certain First Loan Modification Agreement dated as of May 24, 2001 (as may be
amended from time to time, the "Loan Agreement"), and (ii) a certain Accounts
Receivable Financing Agreement dated as of February 28, 2001, between Borrower
and Bank , as amended by a certain First Modification to the Account Receivable
Financing Agreement dated as of May 24, 2001(as may be amended from time to
time, the "Financing Agreement"). The Loan Agreement established: (i) an
equipment line of credit in favor of Borrower in the maximum principal amount of
Two Million Dollars ($2,000,000.000) (the "Committed Equipment Line").
Capitalized terms used but not otherwise defined herein shall have the same
meaning as in the Loan Agreement.

Hereinafter, all indebtedness and obligations owing by Borrower to Bank shall be
referred to as the "Obligations".

2.  DESCRIPTION  OF  COLLATERAL.  Repayment of the  Obligations  is
secured by the  Collateral as described in the Loan  Agreement(together with
any other collateral security granted to Bank, the "Security Documents").

Hereinafter, the Security Documents, together with all other documents
evidencing or securing the Obligations shall be referred to as the "Existing
Loan Documents".

3.  DESCRIPTION OF CHANGE IN TERMS.


A.  Modifications to Loan Agreement.

1.  The Loan Agreement shall be amended by deleting the following, appearing as
Section 6.7(b) thereof, in its entirety:

6.7 Financial Covenants.

    Borrowers shall maintain as of the last day of each month unless otherwise
noted:

8

    (b) Maximum Net  Loss/Minimum  Net Profit.  (i) quarterly Net Losses not to
exceed (A) Nineteen Million Five Hundred Thousand Dollars  ($19,500,000.00)  for
the quarter  ending  December  31,  2000,  (B) Seven  Million Two Hundred  Fifty
Thousand Dollars ($7,250,000.00) for the quarter ending March 31, 2001, (C) Four
Million Five Hundred  Thousand  Dollars  ($4,500,000.00)  for the quarter ending
June  30,   2001;   (D)  One  Million  Two  Hundred   Fifty   Thousand   Dollars
($1,250,000.00)  for the quarter ending  September 30, 2001;  (ii) quarterly Net
Profit of at least One Million  Dollars  ($1,000,000.00)  for the quarter ending
December 31, 2001; and (iii) a quarterly Net Profit of One Dollar  ($1.00),  for
each quarter thereafter."


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    and inserting in lieu thereof the following:

6.7     Financial Covenants.

     Borrowers shall maintain as of the last day of each month unless  otherwise
noted:

     (b) Maximum Net  Loss/Minimum  Net Profit.  (i) quarterly Net Losses not to
exceed (A) Nineteen Million Five Hundred Thousand Dollars  ($19,500,000.00)  for
the quarter  ending  December  31,  2000,  (B) Seven  Million Two Hundred  Fifty
Thousand Dollars ($7,250,000.00) for the quarter ending March 31, 2001, (C) Four
Million Five Hundred  Thousand  Dollars  ($4,500,000.00)  for the quarter ending
June  30,   2001;   (D)  One  Million  Two  Hundred   Fifty   Thousand   Dollars
($1,250,000.00)  for the quarter ending  September 30, 2001;  (ii) quarterly Net
Profit of at least One Hundred  Thousand Dollars  ($100,000.00)  for the quarter
ending  December  31,  2001;  and (iii) a  quarterly  Net  Profit of One  Dollar
($1.00), for each quarter thereafter."

2. The Loan Agreement shall be amended by deleting the following definition
appearing as in Section 13 thereof in its entirety:

    "Current   Liabilities"  are  the  aggregate  amount  of  Borrower's  Total
Liabilities  which mature within one (1) year (excluding all Deferred  Revenue),
and which shall include, without limitation,  all obligations and liabilities of
Borrowers to Bank, including all Obligations."

    and inserting in lieu thereof the following:

     "Current   Liabilities"  are  the  aggregate  amount  of  Borrower's  Total
Liabilities  which mature within one (1) year (excluding all Deferred  Revenue),
and which shall include, without limitation,  all obligations and liabilities of
Borrowers to Bank,  including all Obligations but excluding cash secured letters
of credit."

3.  The  Loan  Agreement  shall  be  amended  by  inserting  the  following
definition   appearing  in  Section  13.1  after  the   definition   of  Current
Liabilities:

     "Deferred  Revenue"  is  all  amounts  identified  as  such  in  Borrower's
consolidated  balance  sheet  representing  amounts  that have been  billed  for
services yet to be performed or products yet to be delivered."

4.  The Compliance  Certificate appearing as Exhibit C to the Loan Agreement
is hereby replaced with the Compliance Certificate attached as Exhibit A hereto.

    B.       Waivers.

1.  Bank  hereby  waives  Borrower's  existing  defaults  under the Loan and
Security  Agreement by virtue of Borrower's  failure to comply with the "Maximum
Net Loss/Minimum Net Profit" requirements set forth in Section 6.7(b) thereof as
to the quarter ending September 30, 2001. Bank's waiver of Borrower's compliance
of said affirmative covenant shall apply only to the foregoing specific period.


4. RATIFICATION OF INTELLECTUAL PROPERTY SECURITY AGREEMENT. Borrower hereby
ratifies, confirms and reaffirms, all and singular, the terms and conditions of
a certain Intellectual Property Security Agreement dated as of February 28,
2001, between Borrower and Bank, and acknowledges, confirms and agrees that said
Intellectual Property Security Agreement (including all Exhibits attached
thereto) shall remain in full force and effect and contain an accurate and
complete listing of all Intellectual Property Collateral as defined in said
Intellectual Property Security Agreement.

5.  ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower shall
not, without providing the Bank with thirty (30) days prior written notice: (i)
relocate its principal executive office or add any new offices or business
locations or keep any Collateral in any additional locations, or (ii) change its
state of formation, or (iii) change its organizational structure, (iv) change
its legal name, or (v) change any organizational number (if any) assigned by its
state of formation. Borrower hereby ratifies, confirms and reaffirms, all and
singular, the terms and disclosures contained in certain Perfection Certificates
dated as of February 20, 2001, between Borrower and Bank, and acknowledges,
confirms and agrees that the disclosures and information above Borrower provided
to Bank in the Perfection Certificates have not changed, as of the date hereof.

<PAGE>

6.  AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file financing
statements without notice to Borrower,  with all appropriate  jurisdictions,  as
Bank deems  appropriate,  in order to further perfect or protect Bank's interest
in the Collateral.

7.  CONCERNING REVISED ARTICLE 9 OF THE UNIFORM COMMERCIAL CODE. The Borrower
affirms and reaffirms that notwithstanding the terms of the Security Documents
to the contrary, (i) that the definition of "Code", "UCC" or "Uniform Commercial
Code" as set forth in the Security Documents shall be deemed to mean and refer
to "the Uniform Commercial Code as adopted by The Commonwealth of Massachusetts
(presently, Mass. Gen. Laws. Ch. 106), may be amended and in effect from time to
time and (ii) the Collateral is all assets of the Borrower. In connection
therewith, the Collateral shall include, without limitation, the following
categories of assets as defined in the Code: goods (including inventory,
equipment and any accessions thereto), instruments (including promissory notes),
documents, accounts (including health-care-insurance receivables, and license
fees), chattel paper (whether tangible or electronic), deposit accounts,
letter-of-credit rights (whether or not the letter of credit is evidenced by a
writing), commercial tort claims, securities and all other investment property,
general intangibles (including payment intangibles and software), supporting
obligations and any and all proceeds of any thereof, wherever located, whether
now owned or hereafter acquired.

8.  CONSISTENT  CHANGES.  The Existing Loan  Documents are hereby  amended
wherever  necessary to reflect the changes  described above.

9.  RATIFICATION OF LOAN DOCUMENTS.  Borrower hereby ratifies, confirms, and
reaffirms all terms and conditions of all security or other  collateral  granted
to the Bank,  and  confirms  that the  indebtedness  secured  thereby  includes,
without limitation, the Obligations.

10. NO DEFENSES OF BORROWER.  Borrower agrees that, as of this date, it has
no defenses against the obligations to pay any amounts under the Obligations.

11. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the
existing Obligations, Bank is relying upon Borrower's representations,
warranties, and agreements, as set forth in the Existing Loan Documents. Except
as expressly modified pursuant to this Loan Modification Agreement, the terms of
the Existing Loan Documents remain unchanged and in full force and effect.
Bank's agreement to modifications to the existing Obligations pursuant to this
Loan Modification Agreement in no way shall obligate Bank to make any future
modifications to the Obligations. Nothing in this Loan Modification Agreement
shall constitute a satisfaction of the Obligations. It is the intention of Bank
and Borrower to retain as liable parties all makers of Existing Loan Documents,
unless the party is expressly released by Bank in writing. No maker will be
released by virtue of this Loan Modification Agreement.


12. RIGHT OF SET-OFF. In consideration of Bank's agreement to enter into this
Loan Modification Agreement, Borrower and any guarantor hereby reaffirm and
hereby grant to Bank, a lien, security interest and right of setoff as security
for all Obligations to Bank, whether now existing or hereafter arising upon and
against all deposits, credits, collateral and property, now or hereafter in the
possession, custody, safekeeping or control of Bank or any entity under the
control of Silicon Valley Bank or in transit to any of them. At any time after
the occurrence and during the continuance of an Event of Default, without demand
or notice, Bank may set off the same or any part thereof and apply the same to
any liability or obligation of Borrower and any guarantor even though unmatured
and regardless of the adequacy of any other collateral securing the loan. ANY
AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT
TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS
RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF THE
BORROWER OR ANY GUARANTOR, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY
WAIVED.

13. JURISDICTION/VENUE. Borrower accepts for itself and in connection with its
properties, unconditionally, the non-exclusive jurisdiction of any state or
federal court of competent jurisdiction in the Commonwealth of Massachusetts in
any action, suit, or proceeding of any kind against it which arises out of or by
reason of this Loan Modification Agreement; provided, however, that if for any
reason Bank cannot avail itself of the courts of the Commonwealth of
Massachusetts, then venue shall lie in Santa Clara County, California.

14. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective
only when it shall have been executed by Borrower and Bank (provided, however,
in no event shall this Loan Modification Agreement become effective until signed
by an officer of Bank in California).

<PAGE>

15. AGED LISTING OF ACCOUNTS RECEIVABLE. The Bank agrees that the requirement of
Borrower to submit aged listings of accounts receivable, as set forth in Section
6.2(a) of the Loan Agreement, shall exist only while there are Obligations
outstanding under the Financing Agreement or upon Bank's request.

         This Loan Modification Agreement is executed as a sealed instrument
under the laws of the Commonwealth of Massachusetts as of the date first written
above.



AGENT:                                    BANK:

VISUAL NETWORKS, INC.                     SILICON VALLEY BANK, doing business as
                                          SILICON VALLEY EAST

By       /s/ Peter J. Minihane            By:      /s/ Steven J. DiPasquale

Name:    Peter J. Minihane                Name:    Steven J. DiPasquale

Title:   Executive Vice President         Title:   Vice President


BORROWERS:

VISUAL NETWORKS, INC.

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President


VISUAL NETWORKS OPERATIONS, INC.

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President


VISUAL NETWORKS INVESTMENTS, INC.

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President


VISUAL NETWORKS TECHNOLOGIES, INC.

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President


VISUAL NETWORKS OF TEXAS, L.P.,
by Visual Networks Texas Operations, Inc., its
General Partner

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President


VISUAL NETWORKS INSURANCE, INC.

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President

<PAGE>




BORROWERS (continued):


INVERSE NETWORK TECHNOLOGY

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President


AVESTA TECHNOLOGIES, INC.

By       /s/ Peter J. Minihane

Name:    Peter J. Minihane

Title:   Executive Vice President



<PAGE>


                                    EXHIBIT A
                             COMPLIANCE CERTIFICATE

TO:               SILICON VALLEY BANK

FROM:             VISUAL NETWORKS, INC., AS AGENT

         The undersigned Responsible Officer of VISUAL NETWORKS, INC. hereby
certifies that in accordance with the terms and conditions of the Loan and
Security Agreement between Borrower and Bank (the "Agreement"), (i) Borrower is
in complete compliance for the period ending ________________ with all required
covenants except as noted below and (ii) all representations and warranties of
Borrower stated in the Agreement are true and correct in all material respects
as of the date hereof. Attached herewith are the required documents supporting
the certification. The Officer further certifies that these are prepared in
accordance with Generally Accepted Accounting Principles (GAAP) and are
consistently applied from one period to the next except as explained in an
accompanying letter or footnotes. The Officer expressly acknowledges that no
borrowings may be requested by the Borrower at any time or date of determination
that Borrower is not in compliance with any of the terms of the Agreement, and
that such compliance is determined not just at the date this certificate is
delivered.

Please indicate compliance status by circling Yes/No under "Complies" column.

Reporting Covenant             Required                           Complies

Financial Statements & CC      Monthly w/in 30 days               Yes      No
Annual (CPA Audited) with CC   FYE within 90 days                 Yes      No
10K, 10Q and 8K                Within 5 days after filing w/ SEC  Yes      No


Financial Covenant             Required        Actual             Complies

Maintain on Monthly Basis
 unless otherwise noted:

Minimum Quick Ratio            .70:1.0         _____:1.0          Yes      No

Maximum (Net Loss) Profit
 (quarterly):                  ($*      )     ($_________)        Yes      No

*(i)   ($19,500,000.00) for the quarter ending 12/31/00;
*(ii)  ($7,250,000.00) for the quarter ending 3/31/01; *(iii) ($4,500,000.00)
         for the quarter ending 6/30/01;
*(iv)  ($1,250,000.00) for the quarter ending 9/30/01;
*(v)   $100,000.00 for the quarter ending 12/31/01;
*(vi)  a quarterly net profit of $1.00 thereafter.

Debt Service Coverage Ratio    **

** See First Loan Modification Agreement to the Loan and Security Agreement

         BANK USE ONLY


         Received By:____________________
         Date:___________________________
         Reviewed By:____________________
         Compliance Status:  Yes / No

Comments Regarding Exceptions:  See Attached.


Sincerely,

______________________________            Date:_______________
SIGNATURE

______________________________
TITLE