Document:

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                                                                     EXHIBIT 4.2

                          CREDIT ENHANCEMENT AGREEMENT

                                      AMONG

                         U.S. BANK NATIONAL ASSOCIATION

                                   AS TRUSTEE,

                             GREENWOOD TRUST COMPANY

                     AS MASTER SERVICER, SERVICER AND SELLER

                                       AND

                   DISCOVER RECEIVABLES FINANCING CORPORATION

                         AS CREDIT ENHANCEMENT PROVIDER

                          -----------------------------

                          DATED AS OF JANUARY 27, 2000

                          ----------------------------

                          DISCOVER CARD MASTER TRUST I

                                  SERIES 2000-1

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                                TABLE OF CONTENTS
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                                                                                         PAGE

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Section 1. Defined Terms ..............................................................    1

Section 2. Loan .......................................................................    2

Section 3. Calculation of Amount of Interest Payable on the Loan ......................    3

Section 4. Payment of Interest on the Loan ............................................    3

Section 5. Repayment of Principal of the Loan .........................................    3

Section 6. Payments to the Holder of the Seller Certificate and the Master Servicer ...    4

Section 7. Deposits to and Withdrawals from the Credit Enhancement Account ............    6

Section 8. Certain Additional Loans ...................................................    5

Section 9. Limited Obligation; Waiver of Setoff; Obligations Absolute .................    6

Section 10. Investments and Information ...............................................    7

Section 11. Servicing Transfer ........................................................    7

Section 12. Representations and Warranties ............................................    7

Section 13. Covenants .................................................................    9

Section 14. Governing Law .............................................................    9

Section 15. Termination ...............................................................    9

Section 16. Notices ...................................................................   10

Section 17. Bankruptcy ................................................................   10

Section 18. Limitation of Remedies ....................................................   11

Section 19. No Petition ...............................................................   11

Section 20. Amendments ................................................................   11

Section 21. Successors and Assigns; Replacement of Credit Enhancement Provider ........   11

Section 22. Participation .............................................................   12
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                  CREDIT ENHANCEMENT AGREEMENT, dated as of January 27, 2000,
among U.S. BANK NATIONAL ASSOCIATION (formerly First Bank National Association,
successor trustee to Bank of America Illinois, formerly Continental Bank,
National Association) as trustee (together with its successors and assigns as
trustee, the "Trustee") for Discover Card Master Trust I (the "Trust"),
GREENWOOD TRUST COMPANY ("Greenwood") as Master Servicer, Servicer and Seller
with respect to the Trust and DISCOVER RECEIVABLES FINANCING CORPORATION as cash
collateral depositor (the "Credit Enhancement Provider").

                               W I T N E S S E T H

                  WHEREAS, Greenwood as Master Servicer, Servicer and Seller and
the Trustee have entered into a Pooling and Servicing Agreement, dated as of
October 1, 1993 (as the same may from time to time be amended, modified or
otherwise supplemented, the "Pooling and Servicing Agreement"), and that certain
Series Supplement, dated as of January 27, 2000 (as the same may from time to
time be amended, modified or otherwise supplemented, the "Series Supplement");

                  WHEREAS, the Trust, pursuant to the Pooling and Servicing
Agreement and the Series Supplement, is issuing $526,316,000 in aggregate
principal amount of Investor Certificates of Discover Card Master Trust I,
Series 2000-1 (the "Series"), which will entitle the holders thereof to interest
during the Revolving Period, the Accumulation Period, and the Amortization
Period, if any, and principal on the Class A Expected Final Payment Date, the
Class B Expected Final Payment Date and during the Amortization Period, if any;

                  WHEREAS, the principal and interest payments on the Investor
Certificates are to be funded by Principal Collections and Finance Charge
Collections received by the Trust on the Receivables; and

                  WHEREAS, it is a condition to the issuance of the Investor
Certificates that at the closing on the date hereof, the Credit Enhancement
Provider make a term loan (the "Loan") to the Trust, for the benefit of the
Investor Certificateholders of the Series, of $39,473,700 (7.5% of the Series
Initial Investor Interest), for deposit in the Credit Enhancement Account to
provide additional funds to make payments on the Investor Certificates under
certain circumstances.

                  NOW, THEREFORE, in consideration of the mutual covenants
herein contained, and other good and valuable consideration, the receipt and
adequacy of which are hereby expressly acknowledged, the parties hereto agree as
follows:

                  SECTION 1. DEFINED TERMS.

                  (a) The capitalized terms used herein and not otherwise
defined herein shall have the meanings assigned to them in the Pooling and
Servicing Agreement or the Series Supplement, as applicable.

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                  (b) The following terms have the definitions set forth below:

                  "Interest Period" means (i) with respect to the initial
Distribution Date, the period commencing on the Series Closing Date and ending
on the day immediately preceding the initial Distribution Date and (ii) with
respect to each subsequent Distribution Date, the period commencing on the
preceding Distribution Date and ending on the day immediately preceding such
Distribution Date.

                  "Lender Rate" means, with respect to each Interest Period, the
prime commercial lending rate per annum established by the Trustee, as in effect
on each day in the Interest Period.

                  "LIBOR-Based Rate" means, with respect to each Interest
Period, the per annum interest rate equal to the London Interbank Offered Rate
which appears on Telerate Page 3750 at approximately 11:00 a.m. (London time)
two LIBOR Business Days prior to the first day of such Interest Period for
deposits of United States dollars for a period of time comparable to the
Interest Period, and in an amount comparable to the principal amount of the
Loan, plus 0.75%.

                  "Portfolio Yield" means, with respect to any Due Period, the
annualized percentage equivalent of a fraction, the numerator of which shall be
the sum of (i) the amount of Finance Charge Collections received during such Due
Period, (ii) the amount of Series Yield Collections for each Series then
outstanding for such Due Period and (iii) the amount of Series Additional Funds
for each Series then outstanding for such Due Period, and the denominator of
which shall be the total amount of Principal Receivables in the Trust as of the
first day of such Due Period.

                  "Provider Amount" means, with respect to each Distribution
Date, the lesser of (i) the unpaid principal amount of the Loan (including any
amounts loaned by the Credit Enhancement Provider pursuant to Section 8 hereof)
and (ii) the amount on deposit in the Credit Enhancement Account, in each case
before giving effect to any payments, allocations or distributions on such
Distribution Date.

                  "Series Interest Payment Amount" means, for any Distribution
Date, an amount equal to the amount of interest payable on the Loan on such
Distribution Date, including any accrued but unpaid interest with respect to
previous Interest Periods and interest thereon, less the amount paid to the
Credit Enhancement Provider on such Distribution Date pursuant to Section 4(a)
hereof. The Series Interest Payment Amount shall be the amount of interest
payable pursuant to this Agreement for purposes of calculating the "Credit
Enhancement Fee" for the purpose of, and as such term is defined in, the Series
Supplement and such amount shall be paid in accordance with the provisions of
the Series Supplement.

                  SECTION 2. LOAN. The amount of the Loan shall be increased by
the amount of any additional loan made by the Credit Enhancement Provider
pursuant to Section 8 hereof.

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                  SECTION 3. CALCULATION OF AMOUNT OF INTEREST PAYABLE ON THE
LOAN.

                  (a) The Loan shall bear interest for each day during each
Interest Period with respect thereto at a rate per annum determined for such day
as follows. To the extent the unpaid portion of the principal of the Loan during
such Interest Period equals or is less than the amount on deposit in the Credit
Enhancement Account, the rate for such Interest Period on such principal portion
shall be the LIBOR-Based Rate. To the extent any portion of the unpaid principal
of the Loan exceeds such amount on deposit, the rate for such Interest Period on
such principal portion shall be the Lender Rate.

                  (b) Interest shall be payable monthly in arrears on each
Distribution Date. Interest on the Loan shall be calculated on the basis of the
actual number of days elapsed during the applicable Interest Period divided by
(i) 360, to the extent the LIBOR-Based Rate is applicable, or (ii) 365 or 366,
as the case may be, to the extent the Lender Rate is applicable. The Trustee
shall, as soon as practicable, notify the Seller, the Master Servicer and the
Credit Enhancement Provider of each determination of the Lender Rate and of the
LIBOR-Based Rate. Each determination thereof by the Trustee pursuant to the
provisions of this Agreement shall be conclusive and binding on the Seller, the
Master Servicer and the Credit Enhancement Provider, in the absence of manifest
error.

                  (c) If any portion of interest due and payable on a
Distribution Date is not paid on such Distribution Date, the unpaid portion of
such interest shall be due and payable on the next succeeding Distribution Date.
Any interest that is not paid on the due date thereof shall accrue interest from
the Distribution Date on which such interest was due and payable to the date
such interest is actually paid at a rate per annum equal to the Lender Rate.

                  SECTION 4. PAYMENT OF INTEREST ON THE LOAN. On each
Distribution Date, the Trustee as administrator of the Credit Enhancement shall
pay or cause to be paid to the Credit Enhancement Provider the amount of accrued
but unpaid interest on the Loan from the funds and in the order of priority set
forth below; provided, however, that such payments shall not exceed the amount
of accrued but unpaid interest on the Loan and that such payments will be made
only to the extent such funds are available:

                  (a) interest and earnings (net of losses and investment
expenses) accrued since the preceding Distribution Date on the Provider Amount;
and

                  (b) the Series Interest Payment Amount, to the extent such
amount has been paid to the Trustee as administrator of the Credit Enhancement
pursuant to the Series Supplement.

                  SECTION 5. REPAYMENT OF PRINCIPAL OF THE LOAN. The principal
amount of the Loan shall be due and payable on the Series Termination Date. The
Trust shall repay the unpaid principal balance of the Loan in full on or before
the Series Termination Date in accordance with the provisions of this Agreement;
provided, however, that

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the unpaid principal amount of the Loan shall only be paid from the funds
described below, and only to the extent such funds are available.

                  (a) If, as of any Distribution Date, after giving effect to
all other deposits to and withdrawals from the Credit Enhancement Account as of
such Distribution Date, the amount on deposit in the Credit Enhancement Account
exceeds the Total Maximum Credit Enhancement Amount, (i) the amount of such
excess, up to the amount, if any, by which the amount on deposit in the Credit
Enhancement Account exceeds the unpaid principal amount of the Loan, shall be
withdrawn from the Credit Enhancement Account and paid to Greenwood on behalf of
the Holder of the Seller Certificate and (ii) the remaining amount of such
excess, if any, after payment of any amounts to be paid to Greenwood on behalf
of the Holder of the Seller Certificate pursuant to clause (i) of this Section
5(a), shall be withdrawn from the Credit Enhancement Account and paid to the
Credit Enhancement Provider for application toward the unpaid principal amount
of the Loan.

                  (b) On the earlier to occur of (i) the Series Termination Date
and (ii) the day on which the Class Invested Amount with respect to each Class
of the Series is paid in full, and after payment of any amounts to be paid on
such day from the Credit Enhancement Account to or for the benefit of the
Investor Certificateholders of the Series, all amounts remaining on deposit in
the Credit Enhancement Account, up to the amount of the unpaid principal amount
of the Loan, shall be withdrawn from such account and paid to the Credit
Enhancement Provider for application toward the unpaid principal amount of the
Loan.

                  SECTION 6. PAYMENTS TO THE HOLDER OF THE SELLER CERTIFICATE
AND THE MASTER SERVICER.

                  (a) On each Distribution Date, the Trustee as administrator of
the Credit Enhancement shall pay or cause to be paid to Greenwood on behalf of
the Holder of the Seller Certificate (i) the interest and earnings (net of
losses and investment expenses) accrued since the preceding Distribution Date on
an amount equal to the positive difference, if any, between (x) the amount on
deposit in the Credit Enhancement Account and (y) the Provider Amount and (ii)
the positive difference, if any, between (x) the amount of interest and earnings
(net of losses and investment expenses) accrued since the preceding Distribution
Date on the Provider Amount and (y) the amount paid to the Credit Enhancement
Provider on such Distribution Date pursuant to Section 4(a).

                  (b) On each Distribution Date, an amount equal to the amount,
if any, paid to the Trustee as administrator of the Credit Enhancement pursuant
to Section 9(b)(27) of the Series Supplement, shall be paid to Greenwood on
behalf of the Holder of the Seller Certificate.

                  (c) On the earlier to occur of (i) the Series Termination Date
and (ii) the day on which the Class Invested Amount with respect to each Class
of the Series is paid in full, and after payment of any amounts to be paid on
such day from the Credit Enhancement Account to or for the benefit of the
Investor Certificateholders of the Series, any amounts remaining on deposit in
the Credit Enhancement Account that are not paid to the Credit Enhancement
Provider

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pursuant to Section 5(b) hereof shall be withdrawn from such account and paid to
Greenwood on behalf of the Holder of the Seller Certificate.

                  SECTION 7. DEPOSITS TO AND WITHDRAWALS FROM THE CREDIT
ENHANCEMENT ACCOUNT.

                  (a) The proceeds of the Loan made by the Credit Enhancement
Provider to the Trust, for the benefit of the Investor Certificateholders of the
Series, on the Series Closing Date and the proceeds of any additional loan made
by the Credit Enhancement Provider pursuant to Section 8 hereof, shall be
deposited into the Credit Enhancement Account. In addition, any amounts paid to
the Trustee as administrator of the Credit Enhancement on any Distribution Date
with respect to the Total Available Credit Enhancement Amount or the Available
Class B Credit Enhancement Amount pursuant to the terms of the Series Supplement
also shall be deposited into the Credit Enhancement Account upon receipt of such
funds by the Trustee.

                  (b) Any withdrawals from the Credit Enhancement Account for
the benefit of the Investor Certificateholders pursuant to Section 9 of the
Series Supplement may be made by the Master Servicer or by the Trustee as
administrator of the Credit Enhancement and shall be deemed to be made first
from amounts on deposit in the Credit Enhancement Account as a result of
payments of Series Excess Servicing and other amounts to the Trustee as
administrator of the Credit Enhancement to fund the Total Available Credit
Enhancement Amount, including any Series Excess Servicing or other such amounts
on deposit in the Credit Enhancement Account as a result of an Alternative
Credit Support Election having been made or as a result of the occurrence of a
Supplemental Credit Enhancement Event, and only after such amounts are exhausted
shall any such withdrawals be deemed to be made from amounts on deposit in the
Credit Enhancement Account that are attributable to the Loan.

                  (c) On or before any Distribution Date on which Greenwood is
the Master Servicer, all payments made pursuant to this Agreement or the Series
Supplement between the Master Servicer or the Holder of the Seller Certificate
and the Credit Enhancement Account, may be aggregated for such Distribution Date
such that Greenwood, acting as Master Servicer and as agent of the Holder of the
Seller Certificate, may make only one payment to the Credit Enhancement Account
in satisfaction of all payments of the Master Servicer and the Holder of the
Seller Certificate pursuant to this Agreement or the Series Supplement, to the
extent that all payment obligations of the Master Servicer and the Holder of the
Seller Certificate to the Credit Enhancement Account on such Distribution Date
exceed all payment obligations of the Credit Enhancement Account to the Master
Servicer and the Holder of the Seller Certificate on such Distribution Date.

                  SECTION 8. CERTAIN ADDITIONAL LOANS.

                  (a) Alternative Credit Support Election. In the event that an
Alternative Credit Support Election is made pursuant to the provisions of the
Series Supplement, Greenwood on behalf of the Holder of the Seller Certificate
may cause the Additional Credit Support Amount to be funded by Series Excess
Servicing and other amounts paid to the Trustee as administrator of the Credit
Enhancement to fund the Available Class B Credit Enhancement

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Amount, pursuant to Section 9 of the Series Supplement, or may request that the
Credit Enhancement Provider make an additional loan in the amount of the
Additional Credit Support Amount. If Greenwood on behalf of the Holder of the
Seller Certificate makes such request, and if the Credit Enhancement Provider
elects to make such loan, the amount of such loan shall be added to the unpaid
principal amount of the Loan. In the event that the Alternative Credit Support
Election does not become effective, the Additional Credit Support Amount (or, if
the entire amount of the Additional Credit Support Amount is not then on deposit
in the Credit Enhancement Account, the portion of the Additional Credit Support
Amount that is then on deposit) shall be withdrawn from the Credit Enhancement
Account and repaid to Greenwood on behalf of the Holder of the Seller
Certificate (or, if such amount was loaned by the Credit Enhancement Provider,
returned to the Credit Enhancement Provider).

                  (b) Notice. The Credit Enhancement Provider shall give prior
written notice to Moody's of the making of any loan by the Credit Enhancement
Provider other than the additional loans described in this Section 8.

                  SECTION 9. LIMITED OBLIGATION; WAIVER OF SETOFF; OBLIGATIONS
ABSOLUTE.

                  (a) Notwithstanding any provision in any other section of this
Agreement to the contrary, the obligation to repay the Loan, together with
interest thereon, shall be without recourse to any Seller, the Master Servicer,
any Servicer, the Trustee, the Trust, any Certificateholder, or any affiliate,
officer, director, employee or person acting on behalf of any of them, and the
obligation to pay such amounts shall be limited solely to the application of
funds pursuant to this Agreement, in the manner and to the extent such funds are
available, except for the direct recourse indemnification obligation of each
successor Master Servicer pursuant to Section 11 hereof. The Credit Enhancement
Provider agrees that its interest in funds on deposit in the Credit Enhancement
Account is subordinated to the interests of the Investor Certificateholders of
the Series, as provided in this Agreement and in the Series Supplement. The
Credit Enhancement Provider further agrees that it shall have no right of setoff
or lender's lien against any Seller, the Master Servicer, any Servicer, the
Trustee, the Trust, or any Certificateholder.

                  (b) The obligations of the Seller, the Trustee, the Credit
Enhancement Provider and the Master Servicer under this Agreement shall be
absolute, unconditional and irrevocable, and shall be performed strictly in
accordance with the terms of this Agreement.

                  SECTION 10. INVESTMENTS AND INFORMATION.

                  (a) The Trustee shall from time to time during the term of
this Agreement invest all amounts on deposit in the Credit Enhancement Account
as the Master Servicer shall direct, which investments shall at all times be
made in compliance with the terms of the Pooling and Servicing Agreement and the
Series Supplement.

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                  (b) The Master Servicer shall provide the Credit Enhancement
Provider with such background information and data with respect to the Credit
Enhancement Account as the Credit Enhancement Provider may reasonably request.

                  (c) The Master Servicer shall obtain the consent of the Credit
Enhancement Provider prior to the investment in any Permitted Investments with a
stated maturity, the maturity of which is longer than as would cause them to
mature on or prior to the following Distribution Date as provided in Section
8(e) of the Series Supplement.

                  SECTION 11. SERVICING TRANSFER. In the event that a successor
Master Servicer is appointed pursuant to the Pooling and Servicing Agreement,
from and after the effective date of such transfer of servicing, the successor
Master Servicer appointed pursuant to the Pooling and Servicing Agreement, and
not the former Master Servicer, shall (a) be responsible for the performance of
all servicing functions to be performed from and after such date, (b) agree to
be bound by the terms, covenants and conditions contained herein applicable to
the Master Servicer and be subject to the duties and obligations of the Master
Servicer hereunder, and (c) agree to indemnify and hold harmless the Credit
Enhancement Provider from and against any and all claims, damages, losses,
liabilities, costs or expenses whatsoever which the Credit Enhancement Provider
may incur (or which may be claimed against the Credit Enhancement Provider) by
reason of the gross negligence or willful misconduct of the successor Master
Servicer in exercising its powers and carrying out its obligations under the
Pooling and Servicing Agreement and the Series Supplement. Such transfer of
servicing shall not affect any rights or obligations of the former Master
Servicer under this Agreement that arose prior to the effective date of the
transfer of servicing, except that such former Master Servicer shall have no
obligation to indemnify the Credit Enhancement Provider as a result of any act
or failure to act of any successor Master Servicer in the performance of the
servicing functions.

                  SECTION 12. REPRESENTATIONS AND WARRANTIES.

                  (a) The Credit Enhancement Provider hereby represents and
warrants to the Master Servicer and the Trustee that:

                  (i) The Credit Enhancement Provider has been duly incorporated
and is validly existing as a corporation in good standing under the laws of the
State of Delaware, and has the corporate power and authority to execute, deliver
and perform its obligations under this Agreement.

                  (ii) This Agreement has been duly authorized, executed and
delivered on the part of the Credit Enhancement Provider.

                  (iii) When executed and delivered, this Agreement will
constitute a valid and binding agreement of the Credit Enhancement Provider
enforceable against the Credit Enhancement Provider in accordance with its
terms, except (A) as the same may be limited by insolvency, bankruptcy or
reorganization or other laws relating to or affecting the enforcement of
creditors' rights and (B) as the same may be limited by general equity
principles (whether

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considered in a proceeding at law or in equity) and by the discretion of the
court before which any proceeding therefor may be brought.

                  (b) The Master Servicer hereby represents and warrants to the
Credit Enhancement Provider and the Trustee that:

                  (i) The Master Servicer has been duly incorporated and is
validly existing as a banking corporation in good standing under the laws of the
State of Delaware, and has the corporate power and authority to execute, deliver
and perform its obligations under the Pooling and Servicing Agreement, the
Series Supplement and this Agreement.

                  (ii) This Agreement, the Pooling and Servicing Agreement and
the Series Supplement have been duly authorized, executed and delivered on the
part of the Master Servicer.

                  (iii) When executed and delivered, each of this Agreement, the
Pooling and Servicing Agreement and the Series Supplement will constitute a
valid and binding agreement of the Master Servicer enforceable against the
Master Servicer in accordance with its terms, except (A) as the same may be
limited by insolvency, bankruptcy, receivership or reorganization or other laws
relating to or affecting the enforcement of creditors' rights and (B) as the
same may be limited by general equity principles (whether considered in a
proceeding at law or in equity) and by the discretion of the court before which
any proceeding therefor may be brought.

                  (c) The Trustee hereby represents and warrants to the Credit
Enhancement Provider and the Master Servicer that:

                  (i) The Trustee is organized, existing and in good standing
under the laws of the United States of America.

                  (ii) The Trustee has full power, authority and right to
execute, deliver and perform this Agreement, the Pooling and Servicing Agreement
and the Series Supplement, and has taken all necessary action to authorize the
execution, delivery and performance by it of this Agreement, the Pooling and
Servicing Agreement and the Series Supplement.

                  (iii) Each of this Agreement, the Pooling and Servicing
Agreement and the Series Supplement have been duly executed and delivered by the
Trustee.

                  SECTION 13. COVENANTS. Greenwood, as Master Servicer and on
behalf of the Holder of the Seller Certificate, covenants and agrees that, so
long as this Agreement shall remain in effect or any monetary obligation arising
hereunder or under the Series Supplement shall remain unpaid, it will change the
terms and provisions of a Credit Agreement with respect to a Greenwood Discover
Card Account or any other Account with respect to which it is the Servicer
(including, without limitation, the calculation of the amount, or the timing, of
charge-offs) only if it does not believe, after a good faith assessment of the
expected effects of such change, that such change will result in a reduction of
the Portfolio Yield, for any Due Period beginning prior to the termination of
the Series, to less than the Base Rate unless such change (i)

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is required by any Requirements of Law or (ii) is deemed necessary by Greenwood
in its sole reasonable judgment to maintain its credit card business on a
competitive basis. For purposes of this Section 13, "Base Rate" shall mean (i)
the weighted average of the Certificate Rates for each Class of each Series then
outstanding plus (ii) 1% per annum. For purposes of the immediately preceding
sentence, the Certificate Rate for each Class that does not have a fixed
Certificate Rate shall be the actual Certificate Rate for such Class for the
Interest Accrual Period commencing in the immediately preceding Due Period. In
the event that any Additional Seller shall transfer Receivables in Additional
Accounts to the Trust, Greenwood on behalf of the Holder of the Seller
Certificate shall cause the Servicer with respect to such Additional Accounts to
make the covenant set forth above with respect to such Additional Accounts.

                  SECTION 14. GOVERNING LAW. THIS AGREEMENT SHALL BE CONSTRUED
IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK, WITHOUT REFERENCE
TO ITS CONFLICT OF LAW PROVISIONS, AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF
THE PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH SUCH LAWS.

                  SECTION 15. TERMINATION. This Agreement shall terminate on the
date on which the Series terminates in accordance with the provisions of the
Pooling and Servicing Agreement and the Series Supplement; provided, however,
that this Agreement may be terminated by the Master Servicer at any time,
without penalty, provided that such termination does not cause the ratings of
the Investor Certificates to be lowered or withdrawn by either of the Rating
Agencies; and provided, further, that all amounts owing to the Credit
Enhancement Provider hereunder with respect to principal and interest on the
Loan shall have been paid in full. Notwithstanding the foregoing, the Credit
Enhancement Provider shall have no rights under this Agreement, and shall not be
entitled to any payments hereunder, if and for so long as there is no Loan
outstanding hereunder and no accrued but unpaid interest.

                  SECTION 16. NOTICES. Unless specifically indicated otherwise
herein, all notices and other communications provided for hereunder shall be in
writing and, if to the Credit Enhancement Provider, addressed to:

                   Discover Receivables Financing Corporation
                                  12 Read's Way
                           New Castle, Delaware 19720
                  Attn: Executive Vice President and Secretary
                              Phone: (302) 323-7167
                               Fax: (302) 323-7393

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or, if to the Seller or the Master Servicer, addressed to:

                             Greenwood Trust Company
                                  12 Read's Way
                           New Castle, Delaware 19720
                               Attn: John J. Coane
                              Phone: (302) 323-7184
                               Fax: (302) 323-7393

or, if to the Trustee, addressed to:

                         U.S. Bank National Association
                               One Illinois Center
                       111 East Wacker Drive - Suite 3000
                             Chicago, Illinois 60601
                             Attn: Patricia M. Child
                              Phone: (312) 228-9413
                               Fax: (312) 228-9401

or as to any party at such other address as shall be designated by such party in
a written notice to the other parties.

                  Any notice or other communication shall be sufficiently given
and shall be deemed given when delivered to the addressee in writing or when
transmitted by telecopier, receipt of which by the addressee is confirmed by
telephone.

                  SECTION 17. BANKRUPTCY. To the extent that the Trustee, the
Master Servicer or Greenwood on behalf of the Holder of the Seller Certificate
makes a payment to the Credit Enhancement Provider or the Credit Enhancement
Provider receives any payment or proceeds with respect to the Loan, which
payment or proceeds or any part thereof are subsequently invalidated, declared
to be fraudulent or preferential, set aside or required to be repaid to a
trustee, receiver or any other party under any state or federal insolvency or
bankruptcy law then, to the extent such payment or proceeds are set aside, the
amount or part thereof intended to be satisfied shall be revived and continue in
full force and effect, as if such payment or proceeds had not been received by
the Credit Enhancement Provider.

                  SECTION 18. LIMITATION OF REMEDIES. The Credit Enhancement
Provider shall not have the right to cause the Loan or any portion thereof to
become due and payable prior to the due date for the Loan as set forth herein.

                  SECTION 19. NO PETITION.

                  (a) The Credit Enhancement Provider, by entering into this
Agreement, hereby covenants and agrees that it will not at any time institute,
join in or otherwise cause the

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institution of, against any Seller, the Master Servicer or the Trust, any
bankruptcy, reorganization, arrangement, insolvency or liquidation proceedings,
or other proceedings under any United States federal or state or similar law
prior to a year and a day after the final payment of all investor certificates
issued by any trust with respect to which Greenwood is the seller.

                  (b) Each of Greenwood and the Trustee, by entering into this
Agreement, hereby covenants and agrees that it will not at any time institute,
join in or otherwise cause the institution of, against the Credit Enhancement
Provider, any bankruptcy, reorganization, arrangement, insolvency or liquidation
proceedings, or other proceedings under any United States federal or state or
similar law prior to a year and a day after the final payment of all investor
certificates issued by any trust with respect to which Greenwood is the seller.

                  SECTION 20. AMENDMENTS. This Agreement shall not be amended or
modified without the written consent of each of the parties hereto. No amendment
hereto shall become effective without prior confirmation from the Rating
Agencies that such amendment will not cause a lowering or withdrawal of the then
current ratings of the Investor Certificates of the Series. The Master Servicer
shall provide a copy of any amendment hereto to the Rating Agencies.

                  SECTION 21. SUCCESSORS AND ASSIGNS; REPLACEMENT OF CREDIT
ENHANCEMENT PROVIDER.

                  (a) This Agreement shall be binding upon, and inure to the
benefit of, the Trustee, the Sellers, the Servicers, the Master Servicer and the
Credit Enhancement Provider and their respective successors and permitted
assigns.

                  (b) No Seller shall assign its interests hereunder and under
the Pooling and Servicing Agreement or the Series Supplement, or any portion of
such interests, except by an assignment that transfers each such interest to the
same assignee.

                  (c) In the event that a successor trustee is appointed
pursuant to the provisions of the Pooling and Servicing Agreement to replace the
then current Trustee, such successor trustee, from and after its appointment,
shall be the Trustee for purposes of this Agreement and shall assume all of the
rights and obligations of the Trustee hereunder.

                  (d) The Credit Enhancement Provider may not assign any of its
rights or obligations hereunder without the prior written consent of Greenwood
on behalf of the Holder of the Seller Certificate and without prior written
confirmation from the Rating Agencies that such assignment will not result in
the lowering or withdrawal of the rating of any Class of any Series then
outstanding.

                  SECTION 22. PARTICIPATION. Any successor Credit Enhancement
Provider that is not a special-purpose corporation that is an affiliate of
Greenwood may, without the consent of the Trustee, the Trust, any Seller, the
Master Servicer, any Servicer or any Certificateholder of the Series, sell
participations to one or more banks or other entities in all or a portion of its
rights under this Agreement (including all or a portion of the Loan); provided,

                                       11
<PAGE>   14

however, that (a) the Credit Enhancement Provider's obligations under this
Agreement shall remain unchanged, (b) the Credit Enhancement Provider shall
remain solely responsible to the other parties hereto for the performance of
such obligations, (c) the Trustee, the Trust, the Sellers and the Master
Servicer shall continue to deal solely and directly with the Credit Enhancement
Provider in connection with the Credit Enhancement Provider's rights and
obligations under this Agreement, and (d) the Credit Enhancement Provider shall
retain the sole right to enforce the obligations of the Trustee, the Trust, the
Sellers or the Master Servicer under this Agreement and to approve any
amendment, modification or waiver of any provision of this Agreement.

                                       12
<PAGE>   15

                  IN WITNESS WHEREOF, the parties hereby have caused this
Agreement to be duly executed and delivered by the undersigned thereunto duly
authorized as of the day and year first above written.

                                 DISCOVER RECEIVABLES FINANCING
                                 CORPORATION,
                                 as Credit Enhancement Provider

                                 By /s/ Richard W. York
                                   --------------------------------------------
                                   Name:  Richard W. York
                                   Title:  Vice President

                                 GREENWOOD TRUST COMPANY,
                                 as Master Servicer, Servicer and Seller

                                 By /s/ John J. Coane
                                   --------------------------------------------
                                   Name:  John J. Coane
                                   Title:  Vice President, Chief Accounting
                                   Officer and Treasurer

                                 U.S. BANK NATIONAL ASSOCIATION, as Trustee

                                 By /s/ Patricia M. Child
                                   --------------------------------------------
                                   Name:  Patricia M. Child
                                   Title:  Vice President

                                       13<PAGE>   1
EXHIBIT 4.3

--------------------------------------------------------------------------------
          BOOK-ENTRY-ONLY COLLATERALIZED MORTGAGE OBLIGATIONS (CMOS) -
             WITHOUT OWNER OPTION TO REDEEM/PASS-THROUGH SECURITIES/
                           AND ASSET-BACKED SECURITIES
--------------------------------------------------------------------------------

                           Letter of Representations*
                     [to be Completed by Issuer and Agent]

                  Discover Card Master Trust I, Series 2000-1
                  -------------------------------------------
                                [Name of Issuer]

                         U.S. Bank National Association
                         ------------------------------
                                [Name of Agent]

                                                                January 27, 2000
                                                                ----------------
                                                                          [Date]

Attention:  General Counsel's Office
The Depository Trust Company
55 Water Street 49th Floor
New York, NY 10041-0099

         Re:     Floating Rate Class A Credit Card Pass-Through Certificates and
                 ---------------------------------------------------------------
                 Floating Rate Class B Credit Card Pass-Through Certificates,
                 ---------------------------------------------------------------
                 Discover Card Master Trust 1, Series 2000-1
                 ---------------------------------------------------------------
                                          [Issue description ("The Securities")]

Ladies and Gentlemen:

         This letter sets forth our understanding with respect to certain
matters relating to the Securities. Agent shall act as trustee, paying agent,
fiscal agent, or other such agent of Issuer with respect to the Securities. The
Securities have been issued pursuant to a trust indenture, trust agreement,
pooling and servicing agreement or other such document authorizing the issuance
of

---------------------
*    This Letter of Representations includes the Addendum attached hereto,
     which modifies and supercedes this Letter of Representations to the extent
     set forth therein.
<PAGE>   2
the Securities dated October 1, 1993 (the "Document"). Morgan Stanley & Co.
Incorporated; ABN AMRO Incorporated; Barclays Capital Inc.; Commerzbank Capital
Markets Corp.; Deutsche Bank Securities Inc. ["Underwriter/Placement Agent"] is
distributing the Securities through The Depository Trust Company ("DTC").

         To induce DTC to accept the Securities as eligible for deposit at DTC,
and to act in accordance with its Rules with respect to the Securities, Issuer
and Agent make the following representations to DTC:

         1. Prior to closing on the Securities on January 27, 2000 there shall
be deposited with DTC one or more Security certificates registered in the name
of DTC's nominee, Cede & Co., for each stated maturity of the Securities in the
face amounts set forth on Schedule A hereto, the total of which represents 100%
of the principal amount of such Securities. If however, the aggregate principal
amount of any maturity exceeds $400 million, one certificate shall be issued
with respect to each $400 million of principal amount and an additional
certificate shall be issued with respect to any remaining principal amount. Each
Security certificate shall bear the following legend:

               Unless this certificate is presented by an authorized
      representative of The Depository Trust Company, a New York corporation
      ("DTC"), to Issuer or its agent for registration of transfer, exchange, or
      payment, and any certificate issued is registered in the name of Cede &
      Co. or in such other name as is requested by an authorized representative
      of DTC (and any payment is made to Cede & Co. or to such other entity as
      is requested by an authorized representative of DTC), ANY TRANSFER,
      PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS
      WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an
      interest herein.

Issuer represents:

         The Security certificate(s) shall remain in Agent's custody as a
"Balance Certificate" subject to the provisions of the Balance Certificate
Agreement between Agent and DTC currently in effect.

         On each day on which Agent is open for business and on which it
receives an instruction originated by a DTC participant ("Participant") through
DTC's Deposit/Withdrawal at Custodian ("DWAC") system to increase the
Participant's account by a specified number of Securities (a "Deposit
Instruction"), Agent shall, no later than 6:30 p.m. (Eastern Time) that day,
either approve or cancel the Deposit Instruction through the DWAC system.

         On each day on which Agent is open for business and on which it
receives an instruction originated by Participant through the DWAC system to
decrease the Participant's

<PAGE>   3
account by a specified number of Securities (a "Withdrawal Instruction"), Agent
shall, no later than 6:30 pm. (Eastern Time) that day, either approve or cancel
the Withdrawal Instruction through the DWAC system.

         Agent agrees that its approval of a Deposit or Withdrawal Instruction
shall be deemed to be the receipt by DTC of a new reissued or reregistered
certificated Security on registration of transfer to the name of Cede & Co. for
the quantity of Securities evidenced by the Balance Certificate after the
Deposit or Withdrawal Instruction is effected.

         2. Issuer: (a) understands that DTC has no Obligation to, and will not,
communicate to its Participants or to any person having an interest in the
Securities any information contained in the Security certificate(s); and (b)
acknowledges that neither DTC's Participants nor any person having an interest
in the Securities shall be deemed to have notice of the provisions of the
Security certificates by virtue of submission of such certificate(s) to DTC.

         3. In the event of any solicitation of consents from or voting by
holders of the Securities, Issuer or Agent shall establish a record date for
such purposes (with no provision for revocation of consents or votes by
subsequent holders) and shall send notice of such record date to DTC no fewer
than 15 calendar days in advance of such record date. Notices to DTC pursuant to
this Paragraph by telecopy shall be directed to DTC's Reorganization Department,
Proxy Unit at (212) 855-5181 or (212) 855-5182. If the party sending the notice
does not receive a telecopy receipt from DTC confirming that the notice has been
received, such party shall telephone (212) 855-5202. Notices to DTC pursuant to
this Paragraph, by mail or by any other means, shall be sent to:

                         Supervisor, Proxy Unit
                         Reorganization Department
                         The Depository Trust Company
                         55 Water Street 50th Floor
                         New York, NY 10041-0099

         4. In the event of a full or partial redemption, Issuer or Agent shall
send a notice to DTC specifying: (a) the amount of the redemption or refunding;
(b) in the case of a refunding, the maturity date(s) established under the
refunding; and (c) the date such notice is to be distributed to Security holders
(the "Publication Date"). Such notice shall be sent to DTC by a secure means
(e.g. legible telecopy, registered or certified mail, overnight delivery) in a
timely manner designed to assure that such notice is in DTC's possession no
later than the close of business on the business day before or, if possible, two
business days before the Publication Date. Issuer or Agent shall forward such
notice either in a separate secure transmission for each CUSIP number or in a
secure transmission for multiple CUSIP numbers (if applicable) which includes a
manifest or list of each CUSIP number submitted in that transmission. (The party
sending such notice shall have a method to verify subsequently the use of such
means and the timeliness of such notice). The Publication Date shall be no fewer
than 30 days nor more than 60 days prior to the redemption date or, in the case
of an advance refunding, the date that the proceeds are deposited in escrow.
Notices to DTC pursuant to this Paragraph by telecopy shall

<PAGE>   4
be directed to DTC's Call Notification Department at (516) 227-4164 or (516)
227-4190. If the party sending the notice does not receive a telecopy receipt
from DTC confirming that the notice has been received, such party shall
telephone (516) 227-4070. Notices to DTC pursuant to this Paragraph, by mail or
by any other means, shall be sent to:

                        Manager, Call Notification Department
                        The Depository Trust Company
                        711 Stewart Avenue
                        Garden City, NY  11530-4719

         5. In the event of an invitation to tender the Securities (including
mandatory tenders, exchanges, and capital changes), notice by Issuer or Agent to
Security holders shall be sent to DTC specifying the terms of the tender and the
Publication Date of such notice. Such notice shall be sent to DTC by a secure
means (e.g. legible telecopy, registered or certified mail, overnight delivery)
in a timely manner designed to assure that such notice is in DTC's possession no
later than the close of business on the business day before or, if possible, two
business days before the Publication Date. Issuer or Agent shall forward such
notice either in a separate secure transmission for each CUSIP number or in a
secure transmission for multiple CUSIP numbers (if applicable) which includes a
manifest or list of each CUSIP number submitted in that transmission. (The party
sending such notice shall have a method to verify subsequently the use and
timeliness of such notice.) Notices to DTC pursuant to this Paragraph and
notices of other corporate actions by telecopy shall be directed to DTC's
Reorganization Department at (212) 855-5488. If the party sending the notice
does not receive a telecopy receipt from DTC confirming that the notice has been
received, such party shall telephone (212) 855-5290. Notices to DTC pursuant to
this Paragraph, by mail or by any other means, shall be sent to:

                        Manager, Reorganization Department
                        Reorganization Window
                        The Depository Trust Company
                        55 Water Street 50th Floor
                        New York, NY  10041-0099

         6. It is understood that if the Security holders shall at any time have
the right to tender the Securities to Issuer and require that Issuer repurchase
such holders' Securities pursuant to the Document and Cede & Co., as nominee of
DTC, or its registered assigns, as the record owner, is entitled to tender the
Securities, such tenders will be effected by means of DTC's Repayment Option
Procedures. Under the Repayment Option Procedures, DTC shall receive, during the
applicable tender period, instructions from its Participants to tender
Securities for purchase. Issuer and Agent agree that such tender for purchase
may be made by DTC by means of a book-entry credit of such Securities to the
account of Agent, provided that such credit is made on or before the final day
of the applicable tender period. DTC agrees that promptly after the recording of
any such book-entry credit, it will provide to Agent an Agent Receipt and
Confirmation or the equivalent, in accordance with the Repayment Option
Procedures, identifying the Securities and the aggregate principal amount
thereof as to which such tender for purchase has been made.

<PAGE>   5
         Agent shall send DTC notice regarding such optional tender by hand or
by a secure means (e.g., legible facsimile transmission, registered or certified
mail, overnight delivery) in a timely manner designed to assure that such notice
is in DTC's possession no later than the close of business two business days
before the Publication Date. The Publication Date shall be no fewer than 15 days
prior to the expiration date of the applicable tender period. Such notice shall
state whether any partial redemption of the Securities is scheduled to occur
during the applicable optional tender period. Notices to DTC pursuant to this
Paragraph by telecopy shall be directed to DTC's Put Bond Unit at (212)
855-5235. If the party sending the notice does not receive a telecopy receipt
from DTC confirming that the notice has been received, such party shall
telephone (212) 855-5230. Notices to DTC pursuant to this Paragraph, by mail or
by any other means, shall be sent to:

                        Supervisor, Put Bond Unit
                        Reorganization Window
                        The Depository Trust Company
                        55 Water Street 50th Floor
                        New York, NY  10041-0099

         7. All notices and payment advices sent to DTC shall contain the CUSIP
number of the Securities.

         8. Issuer or Agent shall send DTC written notice with respect to the
dollar amount per $1,000 original face value (or other minimum authorized
denomination if less than $1,000 face value) payable on each payment date
allocated as to the interest and principal portions thereof preferably five, but
no fewer than two, business days prior to such payment date. Such notices, which
shall also contain the current pool factor, any special adjustments to
principal/interest rates (e.g., adjustments due to deferred interest or
shortfall), and Agent contact's name and telephone number, shall be sent by
telecopy to DTC's Dividend Department at (212) 855-4555, and receipt of such
notices shall be confirmed by telephoning (212) 855-4550. Notices to DTC,
pursuant to this Paragraph, by mail or by any other means, shall be sent to:

                        Manager, Announcements
                        Dividend Department
                        The Depository Trust Company
                        55 Water Street 25th Floor
                        New York, NY  10041-0099

         9. Issuer represents:  The interest accrual period is payment date to
payment date.

         10. Issuer or Agent shall provide a written notice of interest payment
information, including the stated coupon rate information, to DTC as soon as the
information is available. Issuer or Agent shall provide such notice directly to
DTC electronically, as previously arranged by Issuer or Agent and DTC. If
electronic transmission has not been arranged, absent any other arrangements
between Issuer or Agent and DTC, such information shall be sent by

<PAGE>   6
telecopy to DTC's Dividend Department at (212) 855-4555 or (212) 855-4556. If
the party sending the notice does not receive a telecopy receipt from DTC
confirming that the notice has been received, such party shall telephone (212)
855-4550. Notices to DTC pursuant to this Paragraph, by mail or by any other
means, shall be sent to DTC's Dividend Department as indicated in Paragraph 8.

         11. Interest payments and principal payments that are part of periodic
principal-and-interest payments shall be received by Cede & Co., as nominee of
DTC, or its registered assigns, in same-day funds no later than 2:30 p.m.
(Eastern Time) on each payment date. Issuer shall remit by 1:00 p.m. (Eastern
Time) on the payment date all such interest payments due Agent, or at such
earlier time as may be required by Agent to guarantee that DTC shall receive
payment in same-day funds no later than 2:30 p.m. (Eastern Time) on the payment
date. Absent any other arrangements between Issuer or Agent and DTC, such funds
shall be wired to the Dividend Deposit Account number that will be stamped on
the signature page hereof at the time DTC executes this Letter of
Representations.

         12. Issuer or Agent shall provide DTC's Dividend Department, no later
than 12:00 noon (Eastern Time) on the payment date, automated notification of
CUSIP-level detail. If the circumstances prevent the funds paid to DTC from
equaling the dollar amount associated with the detail payments by 12:00 noon
(Eastern Time), Issuer or Agent must provide CUSIP-level reconciliation to DTC
no later than 2:30 p.m. (Eastern Time). Reconciliation must be provided by
either automated means or written format. Such reconciliation notice, if sent by
telecopy, shall be directed to DTC Dividend Department at (212) 855-4633 and
receipt of such reconciliation notice shall be confirmed by telephoning (212)
855-4430.

         13. Maturity and redemption payments allocated with respect to each
CUSIP number shall be received by Cede & Co., as nominee of DTC, or its
registered assigns, in same-day funds no later than 2:30 p.m. (Eastern Time) on
the payment date. Issuer shall remit by 1:00 p.m. (Eastern Time) on the payment
date all such maturity and redemption payments due Agent, or at such earlier
time as required by Agent to guarantee that DTC shall receive payment in
same-day funds no later than 2:30 p.m. (Eastern Time) on the payment date.
Absent any other arrangements between Issuer or Agent and DTC, such funds shall
be wired to the Redemption Deposit Account number that will be stamped on the
signature page hereof at the time DTC executes this Letter of Representations.

         14. Principal payments (plus accrued interest, if any) as the result of
optional tenders for purchase effected by means of DTC's Repayment Option
Procedures shall be received by Cede & Co., as nominee of DTC, or its registered
assigns, in same-day funds no later than 2:30 p.m. (Eastern Time) on the payment
date. Issuer shall remit by 1:00 p.m. (Eastern Time) on the payment date all
such reorganization payments due Agent, or at such earlier time as required by
Agent to guarantee that DTC shall receive payment in same-day funds no later
than 2:30 p.m. (Eastern Time) on the payment date. Absent any other arrangements
between Issuer or Agent and DTC, such funds shall be wired to the Reorganization
Deposit Account number that will be stamped on the signature page hereof at the
time DTC executes this Letter of Representations.

<PAGE>   7
         15. Agent shall send DTC all periodic certificate holders remittance
reports with respect to the Securities. If sent by facsimile transmission, such
reports shall be sent to (212) 855-4777. If the party sending the report does
not receive a telecopy receipt from DTC confirming that the notice has been
received, such party shall telephone (212) 855-4590.

         16. DTC may  direct  Issuer or Agent to use any other  number or
address as the number or address to which notices or payments of interest or
principal may be sent.

         17. In the event of a redemption, acceleration, or any other similar
transaction (e.g., tender made and accepted in response to Issuer's or Agent's
invitation) necessitating a reduction in the aggregate principal amount of
Securities outstanding or an advance refunding of part of the Securities
outstanding, DTC, in its discretion: (a) may request Issuer or Agent to issue
and authenticate a new Security certificate; or (b) may make an appropriate
notation on the Security certificate indicating the date and amount of such
reduction in principal except in the case of final maturity, in which case the
certificate will be presented to Issuer or Agent prior to payment, if required.

         18. In the event that Issuer determines that beneficial owners of
Securities shall be able to obtain certificated Securities, Issuer or Agent
shall notify DTC of the availability of certificates. In such event, Issuer or
Agent shall issue, transfer, and exchange certificates in appropriate amounts,
as required by DTC and others.

         19. DTC may discontinue providing its services as securities depository
with respect to the Securities at any time be giving reasonable notice to Issuer
or Agent (at which time DTC will confirm with Issuer or Agent the aggregate
principal amount of Securities outstanding). Under such circumstances, at DTC's
request Issuer and Agent shall cooperate fully with DTC by taking appropriate
action to make available one or more separate certificates evidencing Securities
to any Participant having Securities credited to its DTC accounts.

         20. Nothing herein shall be deemed to require Agent to advance funds on
behalf of Issuer.

         21. This Letter of Representations may be executed in any number of
counterparts, each of which when so executed shall be deemed to be an original,
but all such counterparts together shall constitute but one and the same
instrument.

         22. This Letter of Representations shall be governed by, and construed
in accordance with, the laws of the State of New York, without giving effect to
principles of conflicts of law.

         23. The sender of each notice delivered to DTC pursuant to this Letter
of Representations is responsible for confirming that such notice was properly
received by DTC.

         24. Issuer recognizes that DTC does not in any way undertake to, and
shall not have any responsibility to, monitor or ascertain the compliance of any
transactions in the Securities with the following, as amended from time to time:
(a) any exemptions from

<PAGE>   8
registration under the Securities Act of 1933; (b) the Investment Company Act of
1940; (c) the Employee Retirement Income Security Act of 1974; (d) the Internal
Revenue Code of 1986; (e) any rules of any self-regulatory organizations (as
defined under the Securities Exchange Act of 1934); or (f) any other local,
state, or federal laws or regulations thereunder.

         25. Issuer hereby authorizes DTC to provide to Agent listings of
Participants' holdings, known as Securities Position Listings ("SPLs") with
respect to the Securities from time to time at the request of the Agent. DTC
charges a fee for such SPLs. This authorization, unless revoked by Issuer, shall
continue with respect to the Securities while any Securities are on deposit at
DTC, until and unless Agent shall no longer be acting. In such event, Issuer
shall provide DTC with similar evidence, satisfactory to DTC, of the
authorization of any successor thereto so to act. Requests for SPLs shall be
sent by telecopy to the Proxy Unit of DTC's Reorganization Department at (212)
855-5181 or (212) 855-5182. Receipt of such requests shall be confirmed by
telephoning (212) 855-5202. Requests for SPLs, sent by mail or by any other
means, shall be directed to the address indicated in Paragraph 3.

         26. Issuer and Agent shall comply with the applicable requirements
stated in DTC's Operational Arrangements, as they may be amended from time to
time. DTC's Operational Arrangements are posted on DTC's website at
"www.DTC.org."

         27. The  following  riders(s),  attached  hereto,  are  hereby
incorporated  into  this  Letter  of Representations:

         (1) Addendum;

         (2) Schedule A

<PAGE>   9
NOTES:

A. IF THERE IS AN AGENT (AS DEFINED
IN THIS LETTER OF REPRESENTATIONS),
AGENT AS WELL AS ISSUER MUST SIGN
THIS LETTER. IF THERE IS NO AGENT,
IN SIGNING THIS LETTER ISSUER
ITSELF UNDERTAKES TO PERFORM ALL OF
THE OBLIGATIONS SET FORTH HEREIN.

B. SCHEDULE B CONTAINS STATEMENTS
THAT DTC BELIEVES ACCURATELY
DESCRIBE DTC, THE METHOD OF
EFFECTING BOOK-ENTRY TRANSFERS OF
SECURITIES DISTRIBUTED THROUGH DTC,
AND CERTAIN RELATED MATTERS.

                                          Very truly yours,

                                                  GREENWOOD TRUST COMPANY
                                          --------------------------------------
                                                         [Issuer]

                                          By:          /s/ John J. Coane
                                             -----------------------------------
                                               [Authorized Officer's Signature]

                                                U.S. BANK NATIONAL ASSOCIATION
                                             -----------------------------------
                                                          [Agent]

                                          By:         /s/ Melissa A. Rosal
                                              ----------------------------------
                                               [Authorized Officer's Signature]

Received and Accepted:
THE DEPOSITORY TRUST COMPANY

By:   /s/ Richard B. Nesson
------------------------------

Funds should be wired to:
The Chase Manhattan Bank
ABA #021 000 021
For credit to a/c Cede & Co.
c/o The Depository Trust  Company

[Select Appropriate Account.]

Dividend Deposit Account #066-026776
Redemption Deposit Account #066-027306
Reorganization Deposit Account #066-027608

cc:  Underwriter/Placement Agent
     Underwriter's/Placement Agent's Counsel

<PAGE>   10
                                A D D E N D U M
                                ---------------

                                       to
                Letter of Representations dated January 27, 2000
                  Discover Card Master Trust I, Series 2000-1

General:          For purposes of this Letter of Representations:

                  "Securities" shall mean the $500,000,000 aggregate principal
                  amount of Floating Rate Class A Credit Card Pass-Through
                  Certificates and the $26,316,000 aggregate principal amount of
                  Floating Rate Class B Credit Card Pass-Through Certificates
                  issued by Discover Card Master Trust I, Series 2000-1 and
                  "Security holders" shall mean the holders of such
                  certificates;

                  "Issuer" shall mean Greenwood Trust Company ("Greenwood") on
                  behalf of Discover Card Master Trust I, Series 2000-1; and

                  "Document" shall mean the Pooling and Servicing Agreement
                  dated as of October 1, 1993, as amended and as supplemented by
                  the Series Supplement dated as of January 27, 2000, each by
                  and between Greenwood as Master Servicer, Servicer and Seller
                  and the Agent.

Paragraph 8:      The following is hereby added after the third sentence of
                  Paragraph 8:

                           "Issuer or Agent will forward such notice either in a
                           separate secure transmission for each CUSIP number or
                           in a secure transmission for multiple CUSIP numbers
                           (if applicable) which includes a manifest or list of
                           each CUSIP submitted in that transmission."

Paragraph 16:     The following is hereby inserted after the word "Agent" in
                  line 1 of Paragraph 16:

                           ", and if requested, shall confirm such direction in
                           writing if practicable,"

Paragraph 17:     The following is hereby inserted at the end of Paragraph 17
                  before the period:

                           "provided, however, that this paragraph shall not
                           apply to any event that causes a reduction in the
                           aggregate principal amount of Securities outstanding
                           that occurs in accordance with their terms,
                           including, without limitation, an Amortization Event
                           (as defined in the Document)".

<PAGE>   11
                                   SCHEDULE A

                  DISCOVER CARD MASTER TRUST I, SERIES 2000-1

    $500,000,000 FLOATING RATE CLASS A CREDIT CARD PASS-THROUGH CERTIFICATES
     AND $26,316,000 FLOATING CLASS B CREDIT CARD PASS-THROUGH CERTIFICATES

                            Principal Amount    Maturity Date*     Interest Rate
   Class A Certificates
       CUSIP Number
         25466KCQ0

    Certificate Number:
    ------------------
             1                $400,000,000      August 16, 2007    Floating Rate
             2                $100,000,000      August 16, 2007    Floating Rate

   Class B Certificates
       CUSIP Number
         25466KCR8

    Certificate Number:
    ------------------
             1                $26,316,000       August 16, 2007    Floating Rate

------------------------------

* Last Possible Distribution Date

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