EXHIBIT 4(d)


                               SECURITY AGREEMENT

      The  undersigned,   National   Transaction   Network,   Inc.,  a  Delaware
corporation  with a place  of  business  and  executive  office  located  at 117
Flanders Road,  Westborough,  Massachusetts 01581 (hereinafter  referred to as a
"Debtor") hereby grants to International  Verifact Inc., a Canadian  corporation
with a place of business and  executive  office  located at 79  Torbarrie  Road,
Toronto,  Ontario,  CANADA M3L 1G5 (hereinafter  called the "Secured Party"),  a
security interest in and agrees and acknowledges that Secured Party has and will
continue to have a security interest in the following:

      (A)  All  of  Debtor's  inventory  of  whatever  name,  nature,   kind  or
description,  all Debtor's goods held for sale or lease or to be furnished under
contracts of service, finished goods, work in process, raw materials,  materials
used or  consumed by the  Debtor,  parts,  supplies,  all  wrapping,  packaging,
advertising,  labeling,  and shipping materials,  devices,  names and marks, all
contract rights and documents  relating to any of the foregoing,  whether any of
the foregoing be now existing or hereafter arising,  wherever located, now owned
or  hereafter  acquired  by the Debtor  (all of which is  sometimes  hereinafter
referred to as "Inventory");

      (B) All of the Debtor's presently owned and hereafter acquired  equipment,
machinery,  furniture,  fixtures  and all other  tangible  personal  property of
whatsoever  kind or nature,  together with all proceeds  thereof,  additions and
accessions  thereto or replacements  thereof or  substitutions  therefor (all of
which is sometimes hereinafter referred to as "Equipment");

      (C) All of the  Debtor's  accounts,  accounts  receivable,  notes,  bills,
drafts, acceptances,  instruments, documents, chattel paper and all other debts,
obligations  and liabilities in whatever form owing to the Debtor for goods sold
by it or for  services  rendered  by it, or  however  otherwise  established  or
created, all guaranties and security therefor,  all right, title and interest of
the Debtor in the goods or services which gave rise thereto, including rights of
an unpaid  seller of goods or  services;  whether  any of the  foregoing  be now
existing  or  hereafter  arising,  now or  hereafter  received  by or  owing  or
belonging to the Debtor (all of which are sometimes  hereinafter  referred to as
"Accounts");

      (D) All of the Debtor's general intangibles, including without limitation,
names, goodwill, trade secrets, copyrights,  trademarks, trademark applications,
tradenames, patents, patent applications, licenses, other intellectual property,
permits,  governmental  approvals,  deposit accounts, tax refunds,  claims under
insurance  policies (whether or not proceeds from  Collateral),  other rights to
payment,  rights of setoff, choses in action,  rights under judgments,  computer
programs and software,  contract rights, and all contracts and agreements to, or
of which it is a party or beneficiary,  and all intangible  personal property of
whatsoever kind or nature now owned by the Debtor as well as any and all thereof
that may be hereafter acquired and in and to all proceeds thereof;







      (E) All of the  Debtor's  books and  records,  as they  exist from time to
time, relating to (A) through (D) above, inclusive;

      (F) All other  assets of every nature and  description,  whether it be now
existing or  hereafter  arising and whether now or  hereafter  belonging  to the
Debtor;

(all hereinafter sometimes collectively referred to as "Collateral");  to secure
the payment of all sums due or which may become due under  certain  Notes of the
Debtor  which may be issued  from time to time in up to an  aggregate  principal
amount of One Million Dollars ($1,000,000), such notes to be issued from time to
time pursuant to a certain Convertible Subordinated Note Purchase Agreement (the
"Purchase  Agreement")  by and between the Debtor and Secured Party as of August
18, 1997  (hereinafter  sometimes  collectively  referred to as  "Obligation" or
"Obligations").

I.  WARRANTIES AND COVENANTS.

      The Debtor hereby warrants and covenants that:

      (A) The Equipment and Inventory are used primarily for business purposes.

      (B) The Equipment and Inventory of the Debtor will be kept at the Debtor's
place of  business.  The Debtor will  promptly  notify the Secured  Party of any
change in the  location  of the  Collateral,  and the Debtor will not remove the
Equipment  from its place of business  without the prior written  consent of the
Secured Party.  The Debtor will notify the Secured  Party,  at least twenty (20)
days prior to any such event,  of any change in the  Debtor's  exact legal name,
any change in its place of business or location of Equipment or Inventory or its
establishment of any new place of business or location of Equipment or Inventory
or office where its records concerning Accounts and other assets are kept.

      (C) The Debtor will have and maintain  insurance at all times with respect
to all its  Collateral  against  risks  of fire  (including  so-called  extended
coverage),  theft,  embezzlement  and such  other  risks as  Secured  Party  may
reasonably  require  containing such terms. If and when requested by the Secured
Party,  the  Debtor  shall  furnish  Secured  Party with  certificates  or other
evidence of compliance  with the foregoing  insurance  provision and the Secured
Party may act either in its name or as attorney for the Debtor (for that purpose
by these presents duly  authorized and appointed with full power of substitution
and revocation) in obtaining,  adjusting,  settling and canceling such insurance
and endorsing any drafts in payment of any loss.

      (D) The Debtor will pay promptly when due all taxes and  assessments  upon
its  Collateral  or for its use or operation or upon this  Agreement or upon any
note or notes secured hereby. In its sole discretion, the Secured Party may: (i)
discharge taxes and liens levied or placed on Collateral; (ii) pay for insurance
thereon or the  maintenance  and  preservation  thereof;  or (iii) if the Debtor
shall fail to make required  deposits in respect of F.I.C.A.  or any withholding
taxes, make such deposits or pay such taxes, in whole or in part, or set up such
reserves as the Secured Party in its sole  discretion  deem necessary in respect
of the Debtor's liability  therefor.  Any amount so paid,







deposited  or reserved for shall  constitute a loan for all purposes  hereunder,
and the Debtor promises to repay the Secured Party such amounts upon the Secured
Party's demand.  Nothing herein shall be deemed to obligate the Secured Party to
do any of the  foregoing  and  the  making  of any one or  more  such  payments;
deposits or reserves  shall not  constitute an agreement by the Secured Party to
take any further or similar action or a waiver of any right of the Secured Party
hereunder.

      (E) The  Debtor  will keep its  Collateral  at all times in good order and
repair,  reasonable wear and tear excepted,  and will make necessary renewals of
and replacements to the same with goods of equal value and serviceability,  free
of  all  liens,   security   interests  and  encumbrances,   which  goods  shall
automatically become subject to this Agreement.

II.  ADDITIONAL RIGHTS AND ASSURANCES.

      (A) Subject to Article VI of this Agreement, the Secured Party will at any
time following an occurrence of an Event of Default  hereunder have the right to
take physical  possession of the Collateral  and to maintain such  possession on
the Debtor's  premises or to remove the  Collateral  or any part thereof to such
other places as the Secured  Party may desire.  If the Secured  Party  exercises
such  right,  the Debtor  shall at its sole  expense  upon the  Secured  Party's
request  assemble the same and make it available to the Secured Party at a place
reasonably  convenient  to  the  Secured  Party.  If  any  Inventory  is in  the
possession or control of any of the Debtor's  agents or  processors,  the Debtor
shall,  at the Secured  Party's  request,  notify  them of the  Secured  Party's
security interest therein and, at the Secured Party's request,  instruct them to
hold the same for the Secured Party's account and subject to the Secured Party's
instructions.

      (B) The Secured  Party may at any time after an  occurrence of an Event of
Default (i) in its own name or in the name of others  communicate  with  account
debtors in order to verify with them to the  Secured  Party's  satisfaction  the
existence,  amount and terms of any Accounts and the absence of any  reductions,
discounts,  defenses or offsets with  respect  thereto,  or (ii) notify  account
debtors  that  Collateral  has been  assigned  to the  Security  Party  and that
payments by such debtors  shall be made  directly to the Secured  Party.  At the
Secured Party's request,  the Debtor will notify any or all such debtors of such
assignment,  give  instruction  and/or indicate on billings to such debtors that
their  Accounts  shall be paid to the Secured  Party and/or  supply such debtors
with a copy of this Agreement.

      (C)  Subsequent  to the  occurrence  of any Event of Default,  the Secured
Party shall have full power, in its own name or that of the Debtor,  to collect,
endorse,  compromise,  settle,  sell or  otherwise  deal  with any or all of the
Collateral or proceeds  thereof.  Subsequent  to the  occurrence of any Event of
Default,  the Debtor  agrees upon  request of the  Secured  Party to appoint any
officer or agent of the Secured Party as true and lawful attorney-in-fact,  with
power of substitution, to endorse the name of the Debtor or any of its officers,
trustees or agents upon any Accounts,  notes,  checks,  drafts, money orders, or
other  instruments  of  payment  (including  under any  policy of  insurance  on
Collateral) or Collateral  that may come into possession of the Secured Party in
full or part payment of any amounts owing to Secured Party;  to sign and endorse
the name of the  Debtor or any of its  officers,  trustees  or  agents  upon any
invoice, freight or express







bill, bill of lading,  storage or warehouse  receipts,  drafts against  debtors,
assignments,  verifications  and notices in connection  with  Accounts,  and any
instruments or documents relating thereto or to the Debtor's rights therein;  to
give written  notice to such offices and  officials of the United  States Postal
Service to effect such  change or changes of address so that all mail  addressed
to the Debtor may be delivered  directly to the Secured  Party;  to take any and
all other actions necessary or appropriate to collect, compromise,  settle, sell
or otherwise deal with any or all of the Collateral or proceeds thereof;  and to
obtain,  adjust,  settle and cancel any insurance;  hereby granting to each said
attorney-in-fact or his substitute full power to do any and all things necessary
or appropriate to be done in and about the premises as fully and  effectually as
the  Debtor  might  or  could  do,  and  hereby  ratifying  all  that  any  said
attorney-in-fact  or his  substitute  shall  lawfully  do or cause to be done by
virtue hereof.

      (D) The Debtor  hereby  assigns to the Secured  Party all sums,  including
without  limitation  return of premiums,  which may become payable under any and
all of such Debtor's  policies of insurance and directs each  insurance  company
issuing any such policy to make payment which would  otherwise be due thereunder
to the Debtor directly to the Secured Party.

      (E) In the  event  of the  sale,  exchange  or  disposition  of any of the
Collateral (other than finished goods in the ordinary course of business) or any
interest  therein  (and no such sale,  exchange or other  disposition  is hereby
authorized  or  consented  to),  the Secured  Party's  security  interest  shall
nevertheless  continue in such  Collateral  (including  without  limitation  all
proceeds,  cash and  non-cash)  notwithstanding  such  sale,  exchange  or other
disposition;  and the Secured  Party's receipt of any such proceeds shall not be
deemed or  construed  to be an  authorization  of or  consent  to any such sale,
exchange or other disposition.

      (F) Any and all  instruments,  documents,  policies  and  certificates  of
insurance,  securities,  goods, accounts, choses in action, general intangibles,
chattel paper, cash,  property and the proceeds thereof (whether or not the same
are  Collateral or proceeds  thereof) owned by the Debtor or in which the Debtor
has an interest, which now or hereafter are at any time in possession or control
of the Secured Party or any affiliate of the Secured Party or in transit by mail
or carrier to or from the Secured Party or such  affiliate or in the  possession
of any third party acting in its behalf,  without  regard to whether the Secured
Party or such affiliate received the same in pledge,  for safekeeping,  as agent
for collection or  transmission or otherwise or had  conditionally  released the
same, shall  constitute  security for Obligations and may be applied at any time
to Obligations which are then owing, whether due or not due.

      (G) A carbon, photographic,  or other reproduction of a security agreement
or a financing  statement is sufficient  as a financing  statement to the extent
permitted under applicable law.

III.  EVENTS OF DEFAULT.

      The Debtor shall be in default under this  Agreement upon the happening of
any of the following  events or conditions  (individually  and  collectively  an
"Event of Default"):








      (A) Failure by the Debtor to observe or perform any  covenant or agreement
referred to herein and, if no other grace or cure period is applicable  thereto,
the continuance of such failure for thirty (30) business days; or

      (B) An Event of Default (as defined in the Purchase  Agreement) shall have
occurred and is continuing and such Event of Default has not been annulled.

IV.  REMEDIES.

      (A) If an Event of Default occurs:

              (1) The Secured Party may declare all  obligations  secured hereby
to be immediately due and payable without presentment,  demand, protest or other
notice of any kind, all of which are hereby expressly waived.

              (2) The  Secured  Party may  exercise  and shall  have any and all
rights and remedies accorded it by the Massachusetts  Uniform Commercial Code or
the  Uniform  Commercial  Code as adopted in such  state  whose laws  govern the
disposition of certain Collateral. The requirement of reasonable notice shall be
met, if notice  containing such  information as may be required under applicable
law is mailed,  postage prepaid,  to the Debtor or other person entitled thereto
at least ten (10) days (including  non-business days) before the time of sale or
disposition of the Collateral.

              (3) The Debtor  designates and appoints the Secured Party its true
and lawful  attorney with full power of  substitution  in its own name or in the
name of such Debtor to demand, collect,  receive, receipt for, sue for, compound
and give  acquittance  for,  any and all  amounts  due and to become  due on the
Accounts and to endorse the name of such Debtor on all commercial paper given in
payment or  part-payment  thereof and in its  reasonable  discretion to file any
claim or take any other  action  which the  Secured  Party may  reasonably  deem
necessary or  appropriate  to protect and preserve and realize upon the security
interest  of the Secured  Party in the  Accounts or the  proceeds  thereof.  The
Secured  Party shall also have the right to (i) open all mail  addressed  to the
Debtor;  (ii) change the Post Office box or mailing  address of the Debtor;  and
(iii) use the Debtor's stationery and billing forms or facsimiles  thereof,  for
the purpose of collecting Accounts and realizing upon the Collateral.

      (B) No delay in  accelerating  the maturity of any obligation as aforesaid
or in taking  any other  action  with  respect  to any  Event of  Default  or in
exercising any rights with respect to the  Collateral  such affect the rights of
the Secured Party later to take such action with respect thereto,  and no waiver
as to one Event of Default shall affect rights as to any other default.

V.  MISCELLANEOUS.

      (A) In case any one or more of the provisions  contained  herein should be
invalid,  illegal or  unenforceable  in any respect,  the validity,  legality or
enforceability of the remaining provisions contained herein shall not in any way
be affected or impaired thereby.








      (B) All rights of the Secured Party  hereunder  shall inure to the benefit
of its successors and assigns;  and all obligations of the Debtor shall bind the
successors or assigns of the Debtor.  All the provisions of this Agreement shall
be  construed  by and  administered  in  accordance  with the local  laws of the
Commonwealth of Massachusetts.  This Agreement shall become effective when it is
signed  by the  Debtor.  The  Debtor  acknowledges  receipt  of a copy  of  this
Agreement.

      (C) In the absence of gross negligence or willful misconduct,  neither the
Secured Party nor any  attorney-in-fact  appointed  hereunder shall be liable to
the Debtor or any other person for any act or  omission,  any mistake of fact or
any error of judgment in exercising any right or remedy granted herein.

VI.  FIRST RIGHTS OF BANK.

      The Secured Party and the Debtor acknowledge that the Debtor has granted a
security  interest  to the  Silicon  Valley  Bank  ("Bank")  to  secure  certain
obligations  of the Debtor to the Bank.  Both the  Secured  Party and the Debtor
hereby  expressly  acknowledge  that the  security  interest  in the  Collateral
created hereby is subordinate and junior to the security interest of the Bank in
the Collateral.

      Signed and delivered this 19th day of September 1997.

                                      NATIONAL TRANSACTION NETWORK, INC.


                                      By: /s/ Milton A. Alpern
                                         ----------------------------------
                                                   Milton A. Alpern
                                      Vice President, Finance & Administration

                                      INTERNATIONAL VERIFACT INC.


                                      By: /s/ Peter H. Henry
                                         ----------------------------------
                                                   Peter H. Henry
                                      Vice President, Finance & Administration