Document:

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                                                                 Exhibit 10.31

                            [iBasis, Inc. Letterhead]

                                                                 April 2, 2001

Paul H. Floyd
3200 Masters Drive
Clearwater, FL 33761-1918

Dear Mr. Floyd,

We are pleased to offer you the position of Vice President of Research and
Development at iBasis, Inc. This position is located in Burlington, MA. You
will report to Ofer Gneezy, Chief Executive Officer. You will be responsible
for Research & Development and Engineering for the company.

Your salary will be $180,000 per annum, earned and payable at the semi-monthly
rate of $7,500. Your annual incentive compensation, based on individual and
corporate performance, will be up to $80,000. We will outline the specific
details of your incentive compensation within 90 days of your employment.

You will be provided with relocation assistance including movement of your
household goods at a reasonable cost as well as reimbursement for selling
expenses and closing costs on a new home. In addition, iBasis will provide
you with temporary living for up to four (4) months and will reimburse for
week-end trips for these 4 months. Expense reimbursement for the total
relocation assistance is pre-approved for up to a total of $75,000. Any
expenses above this limit will need additional approval by iBasis which will
be granted at the sole discretion of iBasis. If you resign or are terminated
for cause within 12 months from your start date, you will be responsible for
the reimbursement to iBasis of any and all such relocation expenses paid by
the Company.

You will be eligible to receive a comprehensive benefits package including:
Medical and Dental insurance at nominal cost to the employee, Employee Stock
Purchase Plan, Section 125 Flexible Spending Accounts, an employer-matched
401(k) plan, tuition reimbursement, Company-paid life/disability and group
travel accident insurance, three weeks accrued vacation and eleven (11)
holidays.

In addition, a recommendation will be made to the Board of Directors to grant
you 175,000 shares of iBasis Inc. Incentive Stock Options. The Compensation
Committee of the Board of Directors meets at the end of the quarter to
approve grants. The option price is based on fair market value. You will
receive a copy of the stock plan and your option grant agreement within
ninety (90) days of its approval by the Board. These options vest over a
four-year period.

If iBasis terminates your employment without cause, or if you terminate your
employment with "good reason," in either case within six months after the
occurrence of an acquisition or change in control, then your stock options
will immediately vest and iBasis will continue to pay your salary for nine
months. Such vesting and payment are subject to the terms and conditions
generally applicable within iBasis for such policies.

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Exclosed please find a copy of iBasis' "Proprietary Information and
Inventions Agreement". Upon joining the Company, we ask you to provide us
with a signed copy of this document.

Additionally, we are required by the Immigration Reform and Control Act
(IRCA), to ask you to provide proof that you are authorized to work in the
U.S.

Paul, we look forward to you joining our senior executive team and being part
of our continued leadership in Internet based communications.

We look forward to your formal acceptance of this offer. Please sign and
return the duplicate letter to Claudia Ellermann, Director of International
Recruiting. This offer will remain open until April 6, 2001.

Sincerely,

/s/ Gordon VanderBrug

Gordon VanderBrug
Executive Vice President

I accept this offer of employment and will begin work on Tuesday, April 17th,
2001.

Signature:  Paul H. Floyd                    Date:        4/2/01
          ---------------------------               ---------------------

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                                  iBASIS, INC.

                PROPRIETARY INFORMATION AND INVENTIONS AGREEMENT

         In consideration of my employment or continued employment by iBasis,
Inc. (the "Company"), and the compensation now and hereafter paid to me, I
hereby agree as follows:

         1. RECOGNITION OF COMPANY'S RIGHTS; NONDISCLOSURE. At all times during
the term of my employment and thereafter, I will hold in strictest confidence
and will not disclose, use, lecture upon or publish any of the Company's
Proprietary Information (as defined below), except as such disclosure, use or
publication may be required in connection with my work for the Company, or
unless an officer of the Company expressly authorizes such in writing.

         The term "Proprietary Information" shall mean trade secrets,
confidential knowledge, data or any other proprietary information of the
Company. By way of illustration but not limitation, "Proprietary Information"
includes (a) inventions, trade secrets, ideas, processes, formulas, algorithms,
source and object codes, data, programs, other works of authorship, know-how,
improvements, discoveries, developments, designs and techniques (hereinafter
collectively referred to as "Inventions"); and (b) information regarding plans
for research, development, new products, regulatory matters, marketing and
selling, business plans, budgets and unpublished financial statements, licenses,
prices and costs, suppliers and customers; and information regarding the skills
and compensation of other employees of the Company.

         2. THIRD PARTY INFORMATION. I understand, in addition, that the Company
has received and may, in the future, receive confidential or proprietary
information from third parties ("Third Party Information") subject to a duty on
the Company's part to maintain the confidentiality of such information and to
use it only for certain limited purposes. During the term of my employment and
thereafter, I will hold Third Party Information in the strictest confidence and
will not use or disclose to anyone (except in connection with my work for the
Company) any Third Party Information, unless expressly authorized in writing by
an executive officer of the Company.

         3. ASSIGNMENT OF INVENTIONS

         3.1 ASSIGNMENT. I hereby assign to the Company all my right, title and
interest in and to any and all Inventions (and all patent rights, copyrights,
mask work rights, trademarks, trade secret rights, all other rights throughout
the world in connection therewith, and the goodwill associated with all of the
foregoing (collectively, "Proprietary Rights")), whether or not patentable or
registrable under patent, copyright, trademark or similar statutes, made or
conceived or reduced to practice or learned by me, either alone or jointly with
others, during the period of my employment with the Company. Inventions assigned
to, or as directed by, the

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                                      -2-

Company under this Paragraph 3 are hereinafter referred to as "Company
Inventions." I agree, upon request, to execute, verify and deliver assignments
of the Proprietary Rights to the Company or its designee and I hereby appoint
the Company my attorney-in-fact with respect to the Proprietary Rights for the
purpose of effecting any or all of the Company's rights to the Proprietary
Rights.

         3.2 GOVERNMENT. I also agree to assign to or as directed by the Company
all my right, title and interest in and to any and all Inventions, full title to
which is required to be assigned to the United States of America by a contract
between the Company and United States of America or any of its agencies.

         3.3 WORKS FOR HIRE. I acknowledge that all original works of authorship
which are made by me (solely or jointly with others) within the scope of my
employment and which are protectable by copyright are "works made for hire," as
that term is defined in the United States Copyright Act (17 U.S.C. Section 101).

         4. ENFORCEMENT OF PROPRIETARY RIGHTS. From time to time, I will assist
the Company in every proper way to obtain and enforce United States and foreign
Proprietary Rights relating to Company Inventions in any and all countries. My
obligation to assist the Company with respect to Proprietary Rights relating to
such Company Inventions in any and all countries shall continue beyond the
termination of my employment, but the Company shall compensate me at a
reasonable rate after my termination for the time actually spent by me at the
Company's request on such assistance.

         I hereby waive and quitclaim to the Company any and all claims, of any
nature whatsoever, which I now or may hereafter have for infringement of any
Proprietary Rights assigned hereunder to the Company.

         5. OBLIGATION TO KEEP COMPANY INFORMED. During the period of my
employment, I will promptly disclose all Inventions to the Company fully and in
writing and will hold such Inventions in trust for the sole right and benefit of
the Company. In addition, after termination of my employment, I will promptly
disclose all patent applications filed by me within a year after termination of
employment.

         6. PRIOR INVENTIONS. Inventions, if any, patented or unpatented, which
I made prior to the commencement of my employment with the Company are excluded
from the scope of this Agreement. To preclude any possible uncertainty, I have
set forth in EXHIBIT A attached hereto a complete list of all Inventions (i)
that I have, alone or jointly with others, conceived, developed or reduced to
practice or caused to be conceived, developed or reduced to practice prior to
the commencement of my employment with the Company, (ii) that I consider to be
my property or the property of third parties and (iii) that I wish to have
excluded from the scope of this Agreement. If disclosure of any such Invention
on EXHIBIT A would cause me to violate any prior confidentiality agreement, I
understand that I am not to list such Inventions in Exhibit A but am to inform
the Company that all such Inventions have not been listed for that reason.

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                                      -3-

         7. RESTRICTIVE COVENANTS. I agree that during the period of my
employment by the Company I will not, without the Company's express written
consent, engage in any employment or business activity other than for the
Company. In view of the unique nature of the business of the Company and the
need of the Company to maintain its competitive advantage in the industry, I
agree that, for a period of one (1) year after the termination of my employment
with the Company for any reason whatsoever, I shall not, directly or indirectly,
within the United States of America or its Territories or Possessions or within
any other country in which the Company or any affiliate of the Company is
engaged in or actively contemplating engaging in any activity described below
(i) engage in, (ii) own greater than a 5% interest in, be employed by, or
consult for, or act as an advisor to, any business, person or entity which
engages in, or (iii) otherwise participate in any way in, research, development,
manufacturing, marketing, selling or licensing activities, or in any other
activity, that may reasonably be deemed by the Company to be in competition with
any activity in which the Company or any subsidiary of the Company is then, or
is then contemplating becoming, engaged. During the term of my employment with
the Company and for a period of one (1) year thereafter, I also shall not
solicit, or arrange to have any other person or entity solicit, any person or
entity engaged by the Company as an employee, customer, supplier, or consultant
or advisor to, the Company to terminate such party's relationship with the
Company. The time periods provided for in this Section 7 shall be extended for a
period of time equal to any period of time in which I shall be in violation of
any provision of this Section 7. If at any time the provisions of this Paragraph
7 shall be determined to be invalid or unenforceable, by reason of being vague
or unreasonable as to area, duration or scope of activity, this Paragraph 7
shall be considered divisible and shall become and be automatically amended to
apply to only such area, duration and scope of activity as shall be determined
to be reasonable and enforceable by the court or other body having jurisdiction
over the matter; and I agree that this Paragraph 7, as so amended, shall be
valid and binding as though any invalid or unenforceable provision had not been
included herein.

         8. NO IMPROPER USE OF MATERIALS. During my employment by the Company, I
will not improperly use or disclose any confidential information or trade
secrets, if any, of any former employer or any other person to whom I have an
obligation of confidentiality, and I will not bring onto the premises of the
Company any unpublished documents or any property belonging to any former
employer or any other person to whom I have an obligation of confidentiality
unless consented to in writing by that former employer or person.

         9. NO CONFLICTING OBLIGATION. I represent that my performance of all
the terms of this Agreement and my performance of my duties as an employee of
the Company do not and will not breach any agreement to keep in confidence
information acquired by me in confidence or in trust prior to my employment by
the Company. I have not entered into, and I agree I will not enter into, any
agreement either written or oral in conflict herewith.

         10. RETURN OF COMPANY DOCUMENTS. When I leave the employ of the
Company, I will deliver to the Company any and all drawings, notes, memoranda,
specifications, devices, formulas, storage media, including software, documents
and computer printouts, together with all

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                                      -4-

copies thereof, and any other material containing or disclosing any Company
Inventions, Third Party Information or Proprietary Information of the Company. I
further agree that any property situated on the Company's premises and owned by
the Company, including disks and other storage media, filing cabinets or other
work areas, is subject to inspection by Company personnel at any time with or
without notice. Prior to leaving, I will cooperate with the Company in
completing and signing the Company's termination statement for technical and
management personnel.

         11. LEGAL AND EQUITABLE REMEDIES. Because my services are personal and
unique and because I may have access to and may become acquainted with the
Proprietary Information of the Company, the Company shall have the right to
enforce this Agreement and any of its provisions by injunction, specific
performance or other equitable relief, without bond, without prejudice to any
other rights and remedies that the Company may have for a breach of this
Agreement, and I waive the claim or defense that the Company has an adequate
remedy at law. I shall not, in any action or proceeding to enforce any of the
provisions of this Agreement, assert the claim or defense that such an adequate
remedy at law exists.

         12. NOTICES. Any notices required or permitted hereunder shall be given
to me at the address specified below or at such other address as I shall specify
in writing. Such notice shall be deemed given upon personal delivery to the
appropriate address or if sent by certified or registered mail, three days after
the date of mailing.

         13. GENERAL PROVISIONS.

         13.1 GOVERNING LAW. This Agreement is executed under seal and will be
governed by and construed according to the laws of the Commonwealth of
Massachusetts.

         13.2 ENTIRE AGREEMENT. This Agreement is the final, complete and
exclusive agreement of the parties with respect to the subject matter hereof and
supersedes and merges all prior discussions between us. No modification or
amendment of this Agreement, nor any waiver of any rights under this Agreement,
will be effective unless in writing signed by the party to be charged. Any
subsequent change or changes in my duties, salary or compensation will not
affect the validity or scope of this Agreement. As used in this Agreement, the
period of my employment includes any time during which I may be retained by the
Company as a consultant.

         13.3 SEVERABILITY. If one or more of the provisions in this Agreement
are deemed unenforceable by law, then the remaining provisions will continue in
full force and effect.

         13.4 SUCCESSORS AND ASSIGNS. This Agreement will be binding upon my
heirs, executors, administrators and other legal representatives and will be for
the benefit of the Company, its successors, and its assigns. I may not assign
any of my rights, or delegate any of my obligations, under this Agreement.

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                                      -5-

         13.5 SURVIVAL. The provisions of this Agreement shall survive the
termination of my employment and the assignment of this Agreement by the Company
to any successor in interest or other assignee.

         13.6 EMPLOYMENT. I agree and understand that nothing in this Agreement
shall confer on me any right with respect to continuation of my employment with
the Company, nor shall it interfere in any way with my right or the Company's
right to terminate my employment at any time, with or without cause.

         13.7 WAIVER. No waiver by the Company of any breach of this Agreement
shall be a waiver of any preceding or succeeding breach. No waiver by the
Company of any right under this Agreement shall be construed as a waiver of any
other right. The Company shall not be required to give notice to enforce strict
adherence to all terms of this Agreement.

         13.8. COUNTERPARTS. This Agreement may be executed in counterparts, all
of which together shall for all purposes constitute one Agreement, binding on
each of the parties hereto notwithstanding that each such party shall not have
signed the same counterpart.

         13.9. JURISDICTION AND VENUE; WAIVER OF JURY TRIAL. In case of any
dispute hereunder, the parties will submit to the exclusive jurisdiction and
venue of any court of competent jurisdiction sitting in Suffolk County,
Massachusetts, and will comply with all requirements necessary to give such
court jurisdiction over the parties and the controversy. EACH PARTY HEREBY
WAIVES ANY RIGHT TO A JURY TRIAL AND TO CLAIM OR RECOVER PUNITIVE DAMAGES.

         13.10. DISCLOSURE. I shall disclose the existence and terms of this
Agreement to any employer or other person that I may work for or be engaged by
after the termination of my employment or engagement at the Company. I agree
that the Company may, after notification to me, provide a copy of this Agreement
to any business or enterprise (i) which I may directly or indirectly own,
manage, operate, finance, join, control or participate in the ownership,
management, operation, financing, or control of, or (ii) with which I may be
connected with as an officer, director, employee, partner, principal, agent,
representative, consultant or otherwise, or in connection with which I may use
or permit my name to be used. I will provide the names and addresses of any of
such persons or entities as the Company may from time to time reasonably
request.

         This Agreement shall be effective as of the first day of my employment
with the Company.

         I UNDERSTAND THAT THIS AGREEMENT AFFECTS MY RIGHTS TO INVENTIONS I MAKE
DURING MY EMPLOYMENT, AND RESTRICTS MY RIGHTS TO DISCLOSE OR USE THE COMPANY'S
CONFIDENTIAL INFORMATION OR TO COMPETE WITH THE COMPANY DURING OR SUBSEQUENT TO
MY EMPLOYMENT.

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                                      -6-

         I HAVE READ THIS AGREEMENT CAREFULLY AND UNDERSTAND ITS TERMS. I HAVE
COMPLETELY FILLED OUT EXHIBIT A TO THIS AGREEMENT.

Dated: APRIL 12, 2001.

                                       /s/ PAUL FLOYD
                                       Signature

                                       PAUL H. FLOYD
                                       ---------------------------------
                                       Name of Employee

                               Address:
                                       ---------------------------------

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

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

ACCEPTED AND AGREED TO:

IBASIS, INC.

By:
   -----------------------------------------
          Signature

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           Print

Title:
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                                      -7-

                                    EXHIBIT A

                        [to be completed by the Employee
                         in accordance with Paragraph 6]<Page>

                                                                   EXHIBIT 10.32

                           LOAN AND SECURITY AGREEMENT

         THIS LOAN AND SECURITY AGREEMENT (this "Agreement") dated as of October
9, 2001, 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 IBASIS, INC., a Delaware corporation
with its chief executive office located at 20 Second Avenue, Burlington,
Massachusetts 01803 ("Borrower"), provides the terms on which Bank shall lend to
Borrower and Borrower shall repay Bank. The parties agree as follows:

         1 ACCOUNTING AND OTHER TERMS

         Accounting terms not defined in this Agreement shall be construed
following GAAP. Calculations and determinations must be made following GAAP. The
term "financial statements" includes the notes and schedules. The terms
"including" and "includes" always mean "including (or includes) without
limitation," in this or any Loan Document. Capitalized terms in this Agreement
shall have the meanings set forth in Section 13.

         2 LOAN AND TERMS OF PAYMENT

         2.1 PROMISE TO PAY. Borrower hereby unconditionally promises to pay
Bank the unpaid principal amount of all Credit Extensions and interest on the
unpaid principal amount of the Credit Extensions as and when due in accordance
with this Agreement.

         2.1.1 Revolving Advances.

                  (a) Bank shall make Advances not exceeding (i) the Committed
Revolving Line minus (ii) the amount of all outstanding Letters of Credit
(including drawn but unreimbursed Letters of Credit), minus (iii) the FX
Reserve, and minus (iv) the aggregate outstanding Advances hereunder (including
any Cash Management Services). Amounts borrowed under this Section may be repaid
and reborrowed during the term of this Agreement.

                  (b) To obtain an Advance, Borrower must notify Bank by
facsimile or telephone by 3:00 p.m. Eastern time on the Business Day the Advance
is to be made. If such notification is by telephone, Borrower must promptly
confirm the notification by delivering to Bank a completed Payment/Advance Form
in the form attached as EXHIBIT A. Bank shall credit Advances to Borrower's
deposit account. Bank may make Advances under this Agreement based on
instructions from a Responsible Officer or his or her designee or without
instructions if the Advances are necessary to meet Obligations which have become
due. Bank may rely on any telephone notice given by a person whom Bank believes
is a Responsible Officer or designee. Borrower shall indemnify Bank for any loss
Bank suffers due to such reliance.

                  (c) The Committed Revolving Line terminates on the Revolving
Maturity Date, when the principal amount of all Advances and the unpaid interest
thereon, shall be immediately payable.

         2.1.2 LETTERS OF CREDIT.

                  (a) Bank shall issue or have issued Letters of Credit for
Borrower's account not exceeding (i) the Committed Revolving Line minus (ii) the
outstanding principal balance of any Advances (including any Cash Management
Services), minus (iii) the amount of all Letters of Credit (including drawn but
unreimbursed Letters of Credit), plus an amount equal to any Letter of Credit
Reserves. The face amount of outstanding Letters of Credit (including drawn but
unreimbursed Letters of Credit and any Letter of Credit Reserve) may not exceed

<Page>

$5,000,000.00. Each Letter of Credit shall have an expiry date no later than 180
days after the Revolving Maturity Date provided Borrower's Letter of Credit
reimbursement obligation shall be secured by cash on terms acceptable to Bank on
and after (i) the Revolving Maturity Date if the term of this Agreement is not
extended by Bank, or (ii) the occurrence of an Event of Default hereunder. All
Letters of Credit shall be, in form and substance, acceptable to Bank in its
sole discretion and shall be subject to the terms and conditions of Bank's form
of standard Application and Letter of Credit Agreement. Borrower agrees to
execute any further documentation in connection with the Letters of Credit as
Bank may reasonably request.

                  (b) The obligation of Borrower to immediately reimburse Bank
for drawings made under Letters of Credit shall be absolute, unconditional and
irrevocable, and shall be performed strictly in accordance with the terms of
this Agreement and such Letters of Credit, under all circumstances whatsoever.
Borrower shall indemnify, defend, protect, and hold Bank harmless from any loss,
cost, expense or liability, including, without limitation, reasonable attorneys'
fees, arising out of or in connection with any Letters of Credit.

                  (c) Borrower may request that Bank issue a Letter of Credit
payable in a currency other than United States Dollars. If a demand for payment
is made under any such Letter of Credit, Bank shall treat such demand as an
Advance to Borrower of the equivalent of the amount thereof (plus cable charges)
in United States currency at the then prevailing rate of exchange in San
Francisco, California, for sales of that other currency for cable transfer to
the country of which it is the currency.

                  (d) Upon the issuance of any letter of credit payable in a
currency other than United States Dollars, Bank shall create a reserve (the
"Letter of Credit Reserve") under the Committed Revolving Line for letters of
credit against fluctuations in currency exchange rates, in an amount equal to
ten percent (10%) of the face amount of such letter of credit. The amount of
such reserve may be amended by Bank from time to time to account for
fluctuations in the exchange rate. The availability of funds under the Committed
Revolving Line shall be reduced by the amount of such reserve for so long as
such letter of credit remains outstanding.

         FOREIGN EXCHANGE SUBLIMIT. If there is availability under the Committed
Revolving Line, then Borrower may enter in foreign exchange forward contracts
with the Bank under which Borrower commits to purchase from or sell to Bank a
set amount of foreign currency more than one business day after the contract
date (the "FX Forward Contract"). Bank shall subtract 10% of each outstanding FX
Forward Contract from the foreign exchange sublimit which is a maximum of
$2,000,000.00 (the "FX Reserve"). The total FX Forward Contracts at any one time
may not exceed 10 times the amount of the FX Reserve. Bank may terminate the FX
Forward Contracts if an Event of Default occurs.

         CASH MANAGEMENT SERVICES SUBLIMIT. Borrower may use up to $1,000,000.00
for the Bank's Cash Management Services, which may include merchant services,
direct deposit of payroll, business credit card, and check cashing services
identified in the various cash management services agreements related to such
services Cash Management Services Agreement (the "Cash Management Services").
Such aggregate amounts utilized under the Cash Management Services Sublimit
shall at all times reduce the amount otherwise available for Credit Extensions
under the Committed Revolving Line. Any amounts Bank pays on behalf of Borrower
or any amounts that are not paid by Borrower for any Cash Management Services
will be treated as Advances under the Committed Revolving Line and will accrue
interest at the interest rate applicable to Advances.

         TERM LOAN.

                  (e) On the Closing Date, Bank shall make a Term Loan available
to Borrower.

                  (f) Borrower shall pay thirty (30) equal installments of
principal plus accrued interest (the "Term Loan Payment"). Each Term Loan
Payment is payable on the first (1st) day of each month during the term of the
loan. Borrower's final Term Loan Payment, due on the Term Loan Maturity Date,
shall include all outstanding Term Loan principal and accrued interest.
<Page>

                  (g) The Term Loan shall accrue interest at the aggregate of
one half of one percentage points (0.50%) and the Prime Rate.

         2.2 INTEREST RATE; PAYMENTS.

                  (a) INTEREST RATE. Advances accrue interest on the outstanding
principal balance at a per annum rate equal to the Bank's Prime Rate. After an
Event of Default, Obligations shall bear interest at five percent (5.0%) above
the rate effective immediately before the Event of Default. The interest rate
shall increase or decrease when the Prime Rate changes. Interest is computed on
the basis of a 360 day year for the actual number of days elapsed.

                  (b) PAYMENTS. Interest is payable on the first (1st) day of
each month. Bank may debit any of Borrower's deposit accounts including Account
Number 3300098558 for principal and interest payments or any amounts Borrower
owes Bank. Bank shall promptly notify Borrower when it debits Borrower's
accounts. These debits are not a set-off. Payments received after 12:00 noon
Eastern time are considered received at the opening of business on the next
Business Day. When a payment is due on a day that is not a Business Day, the
payment is due the next Business Day and additional fees or interest, as
applicable, shall continue to accrue.

         2.3 FEES. Borrower shall pay to Bank:

                  (a) FACILITY FEES. (i) a fully earned, non-refundable
Revolving Line Fee of Twelve Thousand Five Hundred Dollars ($12,500.00) due on
the Closing Date, and (ii) a fully earned, non-refundable Term Loan Fee of Ten
Thousand Dollars ($10,000.00) due on the Closing Date;

                  (b) LETTER OF CREDIT FEE. The Borrower shall pay to the Bank a
Letter of Credit Fee of one percent (1.0%) per annum of the face amount of each
Letter of Credit issued upon the issuance of such Letter of Credit by the Bank;

                  (c) FOREIGN EXCHANGE FEES AND CASH MANAGEMENT FEES. The
Borrower shall pay the Bank's customary fees and expenses for foreign exchange
and cash management services; and

                  (d) BANK EXPENSES. All Bank Expenses (including reasonable
attorneys' fees and expenses for documentation and negotiation of this
Agreement, incurred through and after the Closing Date. Bank shall make best
efforts to limit attorney's fees to $7,500.00) when due.

         3 CONDITIONS OF LOANS

         3.1 CONDITIONS PRECEDENT TO INITIAL CREDIT EXTENSION. The obligation of
Bank to make the initial Credit Extension is subject to the condition precedent
that Bank shall have received, in form and substance satisfactory to Bank, the
following:

                  (a) this Agreement;

                  (b) a certificate of the Secretary of Borrower with respect to
articles, bylaws, incumbency and resolutions authorizing the execution and
delivery of this Agreement;

                  (c) a legal opinion of Borrower's in-house counsel, in form
and substance acceptable to Bank;

                  (d) Directed Investment Disclosure Notice and Agreement and
related documents;
<Page>

                  (e) payment of the fees and Bank Expenses then due specified
in Section 2.3 hereof;

                  (f) Certificate of Foreign Qualification (if applicable);

                  (g) Certificate of Good Standing/Legal Existence; and

                  (h) such other documents, and completion of such other
matters, as Bank may reasonably deem necessary or appropriate.

         3.2 CONDITIONS PRECEDENT TO ALL CREDIT EXTENSIONS. Bank's obligations
to make each Credit Extension, including the initial Credit Extension, is
subject to the following:

                  (a) timely receipt of any Payment/Advance Form; and

                  (b) the representations and warranties in Section 5 shall be
materially true on the date of the Payment/Advance Form and on the effective
date of each Credit Extension and no Event of Default shall have occurred and be
continuing, or result from the Credit Extension. Each Credit Extension is
Borrower's representation and warranty on that date that the representations and
warranties in Section 5 remain true.

         3.3 TERMINATION OF EXISTING LINES. At the closing, Bank shall deliver
executed UCC-3 Termination Statements releasing the existing all assets liens of
the Borrower.

         4 CREATION OF SECURITY INTEREST

         4.1 GRANT OF SECURITY INTEREST. Borrower hereby grants Bank, to secure
the payment and performance in full of all of the Obligations and the
performance of each of Borrower's duties under the Loan Documents, a continuing
security interest in, and pledges and assigns to the Bank, the cash or
marketable securities held by the Bank in the Collateral Accounts or any other
deposit account. Borrower warrants and represents that the security interest
granted herein shall be a first priority security interest in the Collateral.
After the occurrence of an Event of Default, Bank may place a "hold" on any
Collateral Account or any other deposit account pledged as Collateral. Borrower
agrees that any disposition of the Collateral in violation of this Agreement, by
either the Borrower or any other Person, shall be deemed to violate the rights
of the Bank under the Code. If the Agreement is terminated, Bank's lien and
security interest in the Collateral shall continue until Borrower fully
satisfies its Obligations.

         5 REPRESENTATIONS AND WARRANTIES

         Borrower represents and warrants as follows:

         5.1 DUE ORGANIZATION AND AUTHORIZATION. Borrower and each Subsidiary is
duly existing and in good standing in its state of formation and qualified and
licensed to do business in, and in good standing in, any state in which the
conduct of its business or its ownership of property requires that it be
qualified except where the failure to do so could not reasonably be expected to
cause a Material Adverse Change. The Borrower has previously delivered to the
Bank a certificate signed by the Borrower and entitled "Perfection Certificate".
The Borrower represents and warrants to the Bank that: (a) the Borrower's exact
legal name is that indicated on the Perfection Certificate and on the signature
page hereof; and (b) the Borrower is an organization of the type, and is
organized in the jurisdiction, set forth in the Perfection Certificate; and (c)
the Perfection Certificate accurately sets forth the Borrower's organizational
identification number or accurately states that the Borrower has none; and (d)
the Perfection Certificate accurately sets forth the Borrower's place of
business, or, if more than one, its chief executive office as well as the
Borrower's mailing address if different, and (e) all other information set forth
on the Perfection Certificate pertaining to the Borrower is accurate and
complete. If the Borrower does not now have an

<Page>

organizational identification number, but later obtains it, Borrower shall
forthwith notify the Bank or such organizational identification number.

         The execution, delivery and performance of the Loan Documents have been
duly authorized, and do not conflict with Borrower's organizational documents,
nor constitute an event of default under any material agreement by which
Borrower is bound. Borrower is not in default under any agreement to which or by
which it is bound in which the default could reasonably be expected to cause a
Material Adverse Change.

         5.2 COLLATERAL. Borrower has good title to the Collateral, free of
Liens.

         5.3 LITIGATION. Except as shown in the Schedule attached hereto, there
are no actions or proceedings pending or, to the knowledge of Borrower's
Responsible Officers, threatened by or against Borrower or any Subsidiary in
which an adverse decision could reasonably be expected to cause a Material
Adverse Change.

         5.4 NO MATERIAL ADVERSE CHANGE IN FINANCIAL STATEMENTS. All
consolidated financial statements for Borrower and any Subsidiary delivered to
Bank fairly present in all material respects Borrower's consolidated financial
condition and Borrower's consolidated results of operations. There has not been
any material deterioration in Borrower's consolidated financial condition since
the date of the most recent financial statements submitted to Bank.

         5.5 SOLVENCY. Borrower is able to pay its debts (including trade debts)
as they mature.

         5.6 REGULATORY COMPLIANCE. Borrower is not an "investment company" or a
company "controlled" by an "investment company" under the Investment Company
Act. Borrower is not engaged as one of its important activities in extending
credit for margin stock (under Regulations T and U of the Federal Reserve Board
of Governors). Borrower has complied in all material respects with the Federal
Fair Labor Standards Act. Borrower has not violated any laws, ordinances or
rules, the violation of which could reasonably be expected to cause a Material
Adverse Change. None of Borrower's or any Subsidiary's properties or assets has
been used by Borrower or any Subsidiary or, to the best of Borrower's knowledge,
by previous Persons, in disposing, producing, storing, treating, or transporting
any hazardous substance other than legally. Borrower and each Subsidiary has
timely filed all required tax returns and paid, or made adequate provision to
pay, all material taxes, except those being contested in good faith with
adequate reserves under GAAP. Borrower and each Subsidiary has obtained all
consents, approvals and authorizations of, made all declarations or filings
with, and given all notices to, all government authorities that are necessary to
continue its business as currently conducted except where the failure to make
such declarations, notices or filings would not reasonably be expected to cause
a Material Adverse Change.

         5.7 FULL DISCLOSURE. No written representation, warranty or other
statement of Borrower in any certificate or written statement given to Bank
taken together with all such written certificates and written statements given
to Bank contains any untrue statement of a material fact or omits to state a
material fact necessary to make the statements contained in the certificates or
statements not misleading (it being recognized by Bank that the projections and
forecasts provided by Borrower in good faith and based upon reasonable
assumptions are not viewed as facts and that actual results during the period or
periods covered by such projections and forecasts may differ from the projected
or forecasted results).

         6 AFFIRMATIVE COVENANTS

         Borrower shall do all of the following:

         6.1 GOVERNMENT COMPLIANCE. Borrower shall maintain its and all
Subsidiaries' legal existence and good standing in its jurisdiction of formation
and maintain qualification in each jurisdiction in which the failure to so
qualify would reasonably be expected to cause a material adverse effect on
Borrower's business or operations.

<Page>

Borrower shall comply, and have each Subsidiary comply, with all laws,
ordinances and regulations to which it is subject, noncompliance with which
could have a material adverse effect on Borrower's business or operations or be
expected to cause a Material Adverse Change.

         6.2 FINANCIAL STATEMENTS, REPORTS, CERTIFICATES.

                  (a) Borrower shall deliver to Bank: (i) as soon as available,
but no later than forty five (45) days after the last day of each quarter, a
company prepared consolidated balance sheet and income statement covering
Borrower's consolidated operations during the period certified by a Responsible
Officer and in a form acceptable to Bank; (ii) as soon as available, but no
later than one hundred and twenty (120) days after the last day of Borrower's
fiscal year, company prepared consolidated financial statements prepared under
GAAP, consistently applied, together with an unqualified opinion on the
financial statements from an independent certified public accounting firm
reasonably acceptable to Bank; and (iii) other financial information reasonably
requested by Bank.

                  (b) Within forty five (45) days after the last day of each
quarter, Borrower shall deliver to Bank with the quarterly financial statements
a Compliance Certificate signed by a Responsible Officer in the form of EXHIBIT
B.

         6.3 TAXES. Borrower shall make, and cause each Subsidiary to make,
timely payment of all material federal, state, and local taxes or assessments
(other than taxes and assessments which Borrower is contesting in good faith,
with adequate reserves maintained in accordance with GAAP) and will deliver to
Bank, on demand, appropriate certificates attesting to such payments.

         6.4 PRIMARY ACCOUNTS. Borrower shall maintain its primary depository
and operating accounts and securities accounts with Bank and some portion of the
Borrower's cash or securities in excess of that amount used for Borrower's
operations shall be maintained or administered through the Bank. Borrower shall,
at all times, maintain in a specifically designated account or accounts at the
Bank (the "Collateral Accounts"), in an aggregate amount equal to either: (a)
one hundred percent (100%) of the then outstanding Obligations, consisting of
certificates of deposit or money market mutual funds; or one hundred and fifteen
percent (115%) of the then outstanding Obligations consisting of commercial
paper, agency notes or other similar instruments.

         6.5 FURTHER ASSURANCES. Borrower shall execute any further instruments
and take further action as Bank reasonably requests to perfect or continue
Bank's security interest in the Collateral or to effect the purposes of this
Agreement.

         7 NEGATIVE COVENANTS

         Borrower shall not do any of the following without the Bank's prior
written consent which shall not be unreasonably withheld.

         7.1 DISPOSITIONS. Convey, sell, lease, transfer or otherwise dispose of
(collectively a "Transfer"), all or any part of the Collateral Accounts.

         7.2 ENCUMBRANCE. Create, incur, or allow any Lien on the Collateral.

         7.3 COMPLIANCE. Become an "investment company" or a company controlled
by an "investment company", under the Investment Company Act of 1940 or
undertake as one of its important activities extending credit to purchase or
carry margin stock, or use the proceeds of any Credit Extension for that
purpose; fail to meet the minimum funding requirements of ERISA, permit a
Reportable Event or Prohibited Transaction, as defined in ERISA, to occur; fail
to comply with the Federal Fair Labor Standards Act or violate any other law or
regulation, if

<Page>

the violation could reasonably be expected to have a material adverse effect on
Borrower's business or operations or would reasonably be expected to cause a
Material Adverse Change, or permit any of its Subsidiaries to do so.

         8 EVENTS OF DEFAULT

         Any one of the following is an Event of Default:

         8.1 PAYMENT DEFAULT. Borrower fails to pay any of the Obligations
within three (3) days after their due date. During the additional period the
failure to cure the default is not an Event of Default (but no Credit Extension
shall be made during the cure period);

         8.2 COVENANT DEFAULT. Borrower does not perform any obligation in
Section 6 or violates any covenant in Section 7 or does not perform or observe
any other material term, condition or covenant in this Agreement, any Loan
Documents, or in any agreement between Borrower and Bank and as to any default
under a term, condition or covenant that can be cured, has not cured the default
within ten (10) days after it occurs, or if the default cannot be cured within
ten (10) days or cannot be cured after Borrower's attempts in the ten (10) day
period, and the default may be cured within a reasonable time, then Borrower
shall have additional time, (of not more than thirty (30) days) to attempt to
cure the default. Grace periods provided under this section shall not apply,
among other things, to financial covenants or any other covenants that are
required to be satisfied, completed or tested by a date certain. During the
additional period the failure to cure the default is not an Event of Default
(but no Credit Extensions shall be made during the cure period);

         8.3 MATERIAL ADVERSE CHANGE. A Material Adverse Change occurs;

         8.4 ATTACHMENT. (i) Any material portion of Borrower's assets is
attached, seized, levied on, or comes into possession of a trustee or receiver
and the attachment, seizure or levy is not removed in ten (10) days; (ii) the
service of process upon the Borrower seeking to attach, by trustee or similar
process any funds of the Borrower on deposit with the Bank; (iii) Borrower is
enjoined, restrained, or prevented by court order from conducting a material
part of its business; (iv) a judgment or other claim becomes a Lien on a
material portion of Borrower's assets; or (v) a notice of lien, levy, or
assessment is filed against any of Borrower's assets by any government agency
and not paid within ten (10) days after Borrower receives notice. These are not
Events of Default if stayed or if a bond is posted pending contest by Borrower
(but no Credit Extensions shall be made during the cure period);

         8.5 INSOLVENCY. (i) Borrower becomes insolvent; (ii) Borrower begins an
Insolvency Proceeding; or (iii) an Insolvency Proceeding is begun against
Borrower and not dismissed or stayed within forty-five (45) days (but no Credit
Extensions shall be made before any Insolvency Proceeding is dismissed);

         8.6 OTHER AGREEMENTS. If there is a default in any agreement to which
Borrower is a party with a third party or parties resulting in the acceleration
of any Indebtedness in an amount in excess of Two Million Dollars ($2,000,000)
or that could result in a Material Adverse Change, and such default has not been
cured, or acceleration reversed, within ten (10) days after it occurs;

         8.7 JUDGMENTS. If a judgment or judgments for the payment of money in
an amount, individually or in the aggregate, of at least Two Million Dollars
($2,000,000) shall be rendered against Borrower and shall remain unsatisfied and
unstayed for a period of ten (10) days (provided that no Credit Extensions will
be made prior to the satisfaction or stay of such judgment); and

         8.8 MISREPRESENTATIONS. If Borrower or any Person acting for Borrower
makes any material misrepresentation or material misstatement now or later in
any warranty or representation in this Agreement or in any writing delivered to
Bank or to induce Bank to enter this Agreement or any Loan Document.
<Page>

         9 BANK'S RIGHTS AND REMEDIES

         9.1 RIGHTS AND REMEDIES. When an Event of Default occurs and continues
Bank may, without notice or demand, do any or all of the following:

                  (a) Declare all Obligations immediately due and payable (but
if an Event of Default described in Section 8.5 occurs all Obligations are
immediately due and payable without any action by Bank);

                  (b) Stop advancing money or extending credit for Borrower's
benefit under this Agreement or under any other agreement between Borrower and
Bank;

                  (c) Make any payments and do any acts it considers necessary
or reasonable to protect its security interest in the Collateral;

                  (d) Apply to the Obligations any (i) balances and deposits of
Borrower it holds, or (ii) any amount held by Bank owing to or for the credit or
the account of Borrower; and

                  (e) Dispose of the Collateral according to the Code.

         9.2 POWER OF ATTORNEY. Borrower hereby appoints Bank its power of
attorney to sign Borrower's name on any documents necessary to perfect or
continue the perfection of any security interest regardless of whether an Event
of Default has occurred until all Obligations have been satisfied in full and
Bank is under no further obligation to make Credit Extensions hereunder. Bank's
foregoing appointment as Borrower's attorney in fact, and all of Bank's rights
and powers, coupled with an interest, are irrevocable until all Obligations have
been fully repaid and performed and Bank's obligation to provide Credit
Extensions terminates.

         9.3 BANK EXPENSES. Any amounts paid by Bank as provided herein are Bank
Expenses and are immediately due and payable, and shall bear interest at the
then applicable rate and be secured by the Collateral. No payments by Bank shall
be deemed an agreement to make similar payments in the future or Bank's waiver
of any Event of Default.

         9.4 REMEDIES CUMULATIVE. Bank's rights and remedies under this
Agreement, the Loan Documents, and all other agreements are cumulative. Bank has
all rights and remedies provided under the Code, by law, or in equity. Bank's
exercise of one right or remedy is not an election, and Bank's waiver of any
Event of Default is not a continuing waiver. Bank's delay is not a waiver,
election, or acquiescence. No waiver hereunder shall be effective unless signed
by Bank and then is only effective for the specific instance and purpose for
which it was given.

         9.5 DEMAND WAIVER. Borrower waives demand, notice of default or
dishonor, notice of payment and nonpayment, notice of any default, nonpayment at
maturity, release, compromise, settlement, extension, or renewal of accounts,
documents, instruments, chattel paper, and guarantees held by Bank on which
Borrower is liable.

         10 NOTICES

         All notices or demands by any party to this Agreement or any other
related agreement must be in writing and be personally delivered or sent by an
overnight delivery service, by certified mail, postage prepaid, return receipt
requested, or by telefacsimile at the addresses listed below. Either Bank or
Borrower may change its notice address by giving the other written notice.
<Page>

         If to Borrower:   iBasis, Inc.
                           20 Second Avenue
                           Burlington, Massachusetts 01803
                           Attn: Mr. D.J. Long, Chief Financial Officer
                           FAX: (781) 505-7345

         If to Bank:       Silicon Valley Bank
                           One Newton Executive Park, Suite 200
                           2221 Washington Street
                           Newton, Massachusetts  02462
                           Attn: Mr. John K. Peck, Vice President
                           Fax:  (617) 969-4395

         with a copy to:   Riemer & Braunstein LLP
                           Three Center Plaza
                           Boston, Massachusetts 02108
                           Attn: David A. Ephraim, Esquire
                           FAX: (617) 880-3456

         11 CHOICE OF LAW, VENUE AND JURY TRIAL WAIVER

         Massachusetts law governs the Loan Documents without regard to
principles of conflicts of law. Borrower and Bank each submit to the exclusive
jurisdiction of the State and Federal courts in Massachusetts; provided,
however, that if for any reason Bank cannot avail itself of such courts in the
Commonwealth of Massachusetts, Borrower accepts jurisdiction of the courts and
venue in Santa Clara County, California. NOTWITHSTANDING THE FOREGOING, THE BANK
SHALL HAVE THE RIGHT TO BRING ANY ACTION OR PROCEEDING AGAINST THE BORROWER OR
ITS PROPERTY IN THE COURTS OF ANY OTHER JURISDICTION WHICH THE BANK DEEMS
NECESSARY OR APPROPRIATE IN ORDER TO REALIZE ON THE COLLATERAL OR TO OTHERWISE
ENFORCE THE BANK'S RIGHTS AGAINST THE BORROWER OR ITS PROPERTY.

BORROWER AND BANK EACH WAIVE THEIR RIGHT TO A JURY TRIAL OF ANY CLAIM OR CAUSE
OF ACTION ARISING OUT OF OR BASED UPON THIS AGREEMENT, THE LOAN DOCUMENTS OR ANY
CONTEMPLATED TRANSACTION, INCLUDING CONTRACT, TORT, BREACH OF DUTY AND ALL OTHER
CLAIMS. THIS WAIVER IS A MATERIAL INDUCEMENT FOR BOTH PARTIES TO ENTER INTO THIS
AGREEMENT. EACH PARTY HAS REVIEWED THIS WAIVER WITH ITS COUNSEL.

         12 GENERAL PROVISIONS

         12.1 SUCCESSORS AND ASSIGNS. This Agreement binds and is for the
benefit of the successors and permitted assigns of each party. Borrower may not
assign this Agreement or any rights or Obligations under it without Bank's prior
written consent which may be granted or withheld in Bank's discretion. Bank has
the right, without the consent of or notice to Borrower, to sell, transfer,
negotiate, or grant participation in all or any part of, or any interest in,
Bank's obligations, rights and benefits under this Agreement, the Loan Documents
or any related agreement.

         12.2 INDEMNIFICATION. Borrower hereby indemnifies, defends and holds
the Bank and its officers, employees and agents harmless against: (a) all
obligations, demands, claims, and liabilities asserted by any other

<Page>

party in connection with the transactions contemplated by the Loan Documents;
and (b) all losses or Bank Expenses incurred, or paid by Bank from, following,
or consequential to transactions between Bank and Borrower (including reasonable
attorneys' fees and expenses), except for losses caused by Bank's gross
negligence or willful misconduct.

         12.3 RIGHT OF SET-OFF. Borrower and any guarantor 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 the 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 LOAN, 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.

         12.4 TIME OF ESSENCE. Time is of the essence for the performance of all
Obligations in this Agreement.

         12.5 SEVERABILITY OF PROVISION. Each provision of this Agreement is
severable from every other provision in determining the enforceability of any
provision.

         12.6 AMENDMENTS IN WRITING; INTEGRATION. All amendments to this
Agreement must be in writing signed by both Bank and Borrower. This Agreement
and the Loan Documents represent the entire agreement about this subject matter,
and supersede prior negotiations or agreements. All prior agreements,
understandings, representations, warranties, and negotiations between the
parties about the subject matter of this Agreement and the Loan Documents merge
into this Agreement and the Loan Documents.

         12.7 COUNTERPARTS. This Agreement may be executed in any number of
counterparts and by different parties on separate counterparts, each of which,
when executed and delivered, are an original, and all taken together, constitute
one Agreement.

         12.8 SURVIVAL. All covenants, representations and warranties made in
this Agreement continue in full force while any Obligations remain outstanding.
The obligation of Borrower in Section 12.2 to indemnify Bank shall survive until
the statute of limitations with respect to such claim or cause of action shall
have run.

         12.9 CONFIDENTIALITY. In handling any confidential information, Bank
shall exercise the same degree of care that it exercises for its own proprietary
information, but disclosure of information may be made: (i) to Bank's
subsidiaries or affiliates in connection with their business with Borrower; (ii)
to prospective transferees or purchasers of any interest in the Credit
Extensions (provided, however, Bank shall use commercially reasonable efforts in
obtaining such prospective transferee's or purchaser's agreement to the terms of
this provision); (iii) as required by law, regulation, subpoena, or other order,
(iv) as required in connection with Bank's examination or audit; and (v) as Bank
considers appropriate in exercising remedies under this Agreement. Confidential
information does not include information that either: (a) is in the public
domain or in Bank's possession when disclosed to Bank, or becomes part of the
public domain after disclosure to Bank; or (b) is disclosed to Bank by a third
party, if Bank does not know that the third party is prohibited from disclosing
the information.

         13 DEFINITIONS

         13.1 DEFINITIONS.
<Page>

         "ACCOUNTS" are all existing and later arising accounts, contract
rights, and other obligations owed Borrower in connection with its sale or lease
of goods (including licensing software and other technology) or provision of
services, all credit insurance, guaranties, other security and all merchandise
returned or reclaimed by Borrower and Borrower's Books relating to any of the
foregoing, as such definition may be amended from time to time according to the
Code.

         "ADVANCE" or "ADVANCES" is a loan advance (or advances) under the
Committed Revolving Line.

         "AFFILIATE" of a Person is a Person that owns or controls directly or
indirectly the Person, any Person that controls or is controlled by or is under
common control with the Person, and each of that Person's senior executive
officers, directors, partners and, for any Person that is a limited liability
company, that Person's managers and members.

         "BANK EXPENSES" are all audit fees and expenses and reasonable costs or
expenses (including reasonable attorneys' fees and expenses) for preparing,
negotiating, administering, defending and enforcing the Loan Documents
(including appeals or Insolvency Proceedings).

         "BORROWER'S BOOKS" are all Borrower's books and records including
ledgers, records regarding Borrower's assets or liabilities, the Collateral,
business operations or financial condition and all computer programs or discs or
any equipment containing the information.

         "BUSINESS DAY" is any day that is not a Saturday, Sunday or a day on
which the Bank is closed.

         "CASH MANAGEMENT SERVICES" are defined in Section 2.1.4.

         "CLOSING DATE" is the date of this Agreement.

         "CODE" is the Uniform Commercial Code as adopted in Massachusetts, as
amended and as may be amended and in effect from time to time.

         "COLLATERAL" is all cash and marketable securities of the Borrower held
by the Bank in the Collateral Account or any other deposit account.

         "COLLATERAL ACCOUNTS" is defined in Section 6.4.

         "COMMITTED REVOLVING LINE" is an Advance or Advances of up to Five
Million Dollars ($5,000,000.00), provided, however, that such funds must first
be used by Borrower to pay off any obligations or indebtedness which may be
owing by Borrower to Bank pursuant to the Existing Committed Revolving Line.

         "CONTINGENT OBLIGATION" is, for any Person, any direct or indirect
liability, contingent or not, of that Person for (i) any indebtedness, lease,
dividend, letter of credit or other obligation of another such as an obligation
directly or indirectly guaranteed, endorsed, co-made, discounted or sold with
recourse by that Person, or for which that Person is directly or indirectly
liable; (ii) any obligations for undrawn letters of credit for the account of
that Person; and (iii) all obligations from any interest rate, currency or
commodity swap agreement, interest rate cap or collar agreement, or other
agreement or arrangement designated to protect a Person against fluctuation in
interest rates, currency exchange rates or commodity prices; but "Contingent
Obligation" does not include endorsements in the ordinary course of business.
The amount of a Contingent Obligation is the stated or determined amount of the
primary obligation for which the Contingent Obligation is made or, if not
determinable, the maximum reasonably anticipated liability for it determined by
the Person in good faith; but the amount may not exceed the maximum of the
obligations under the guarantee or other support arrangement.

         "CREDIT EXTENSION" is each Advance, Letter of Credit, Term Loan,
Exchange Contract, or any other extension of credit by Bank for Borrower's
benefit.
<Page>

         "EQUIPMENT" is all present and future machinery, equipment, tenant
improvements, furniture, fixtures, vehicles, tools, parts and attachments in
which Borrower has any interest.

         "ERISA" is the Employment Retirement Income Security Act of 1974, and
its regulations.

         "EXISTING COMMITTED EQUIPMENT LINE" is the committed equipment line
established pursuant to the Existing Loan Arrangement.

         "EXISTING COMMITTED REVOLVING LINE" is the committed revolving line
established pursuant to the Existing Loan Arrangement.

         "EXISTING LOAN ARRANGEMENT" is the loan arrangement dated as of June
18, 1999, evidenced by, among other documents, a certain Loan and Security
Agreement dated as of June 18, 1999, between Borrower and Bank, as amended by a
certain Loan Modification Agreement dated as of August 17, 2000, between
Borrower and Bank, as further amended by a certain Second Loan Modification
Agreement dated as of November 30, 2000, between Borrower and Bank, and as
further amended by a certain Third Loan Modification Agreement dated as of
August 23, 2001, between Borrower and Bank, as may be further amended from time
to time.

         "FX FORWARD CONTRACT" is defined in Section 2.1.3.

         "FX RESERVE" is defined in Section 2.1.3.

         "GAAP" is generally accepted accounting principles.

         "INDEBTEDNESS" is (a) indebtedness for borrowed money or the deferred
price of property or services, such as reimbursement and other obligations for
surety bonds and letters of credit, (b) obligations evidenced by notes, bonds,
debentures or similar instruments, (c) capital lease obligations and (d)
Contingent Obligations.

         "INSOLVENCY PROCEEDING" is any proceeding by or against any Person
under the United States Bankruptcy Code, or any other bankruptcy or insolvency
law, including assignments for the benefit of creditors, compositions,
extensions generally with its creditors, or proceedings seeking reorganization,
arrangement, or other relief.

         "INVESTMENT" is any beneficial ownership of (including stock,
partnership interest or other securities) any Person, or any loan, advance or
capital contribution to any Person.

         "LETTER OF CREDIT" means a letter of credit or similar undertaking
issued by Bank pursuant to Section 2.1.2.

         "LETTER OF CREDIT RESERVE" has the meaning set forth in Section 2.1.2.

         "LIEN" is a mortgage, lien, deed of trust, charge, pledge, security
interest or other encumbrance.

         "LOAN DOCUMENTS" are, collectively, this Agreement, any note, or notes
or guaranties executed by Borrower or Guarantor, and any other present or future
agreement between Borrower and/or for the benefit of Bank in connection with
this Agreement, all as amended, extended or restated.

         "MATERIAL ADVERSE CHANGE " is: (i) A material impairment in the
perfection or priority of Bank's security interest in the Collateral or in the
value of such Collateral; (ii) a material adverse change in the business,
operations, or condition (financial or otherwise) of the Borrower; (iii) a
material impairment of the prospect of repayment of any portion of the
Obligations, or (iv) Bank determines, based upon information available to it and
in its reasonable judgment, that there is a reasonable likelihood that Borrower
shall fail to comply with one or more of the financial covenants in Section 6
during the next succeeding financial reporting period.
<Page>

         "OBLIGATIONS" are debts, principal, interest, Bank Expenses and other
amounts Borrower owes Bank now or later, including letters of credit, cash
management services, and foreign exchange contracts, if any, and including
interest accruing after Insolvency Proceedings begin and debts, liabilities, or
obligations of Borrower assigned to Bank.

         "PERSON" is any individual, sole proprietorship, partnership, limited
liability company, joint venture, company, trust, unincorporated organization,
association, corporation, institution, public benefit corporation, firm, joint
stock company, estate, entity or government agency.

         "PRIME RATE" is Bank's most recently announced "prime rate," even if it
is not Bank's lowest rate.

         "RESPONSIBLE OFFICER" is each of the Chief Executive Officer,
President, Chief Financial Officer and Controller of Borrower.

         "REVOLVING MATURITY DATE" is the date which is one day prior to the one
year anniversary of the Closing Date.

         "SCHEDULE" is any attached schedule of exceptions.

         "SUBSIDIARY" is for any Person, joint venture, or any other business
entity of which more than 50% of the voting stock or other equity interests is
owned or controlled, directly or indirectly, by the Person or one or more
Affiliates of the Person.

         "TERM LOAN" is a loan of up to Four Million Dollars ($4,000,000.00),
provided, however, that such funds must first be used by Borrower to pay off any
obligations or indebtedness which may be owing by Borrower to Bank pursuant to
the Existing Committed Equipment Line.

         "TERM LOAN MATURITY DATE" is the date which thirty (30) months after
the Closing Date.

         "TERM LOAN PAYMENT" is defined in Section 2.1.5.

            [THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK]
<Page>

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
         executed as a sealed instrument under the laws of the Commonwealth of
         Massachusetts as of the date first above written.

BORROWER:
--------

IBASIS, INC.

By:      /s/ D.J. Long

Name:  D. J. Long

Title:  Vice President, CFO

BANK:
----

SILICON VALLEY BANK, d/b/a
SILICON VALLEY EAST

By  /s/ John K. Peck

Name:  John K. Peck

Title:  Vice President

SILICON VALLEY BANK

By  /s/ Maggie Garcia

Name:  Maggie Garcia

Title:  Loan Admin. Team Leader
         (Signed in Santa Clara County, California)

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00035-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00035-of-00352.parquet"}]]