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                                                                   EXHIBIT 10.32

                              SECURITY AGREEMENT

     THIS SECURITY AGREEMENT is dated November 10, 1997 and is made between
PortaCom Wireless, Inc., a Delaware corporation ("Grantor") and VDC Corporation
Ltd. ("Lender") pursuant to the Loan Agreement referred to below.

                                WITNESSETH THAT:

     WHEREAS, pursuant to that certain Loan Agreement dated November 10, 1997
(as it may hereafter be amended or otherwise modified from time to time, the
"Loan Agreement") between Grantor and the Lender, the Lender has agreed to make
certain loans to Grantor;

     WHEREAS, the obligations of the Lender to make loans under the Loan
Agreement are subject to the condition, among others, that Grantor secure its
obligations to the Lender under the Loan Agreement by the grant of security
interests in the Collateral, as defined and more fully set forth herein; and

     WHEREAS, Grantor is (or will be with respect to after-acquired property)
the legal and beneficial owner and holder of the Collateral (as defined in
Section 1 hereof), and has agreed to grant security interests in such Collateral
to the Lender on the terms and conditions set forth herein.

     NOW, THEREFORE, intending to be legally bound hereby and for value
received, the parties hereto covenant and agree as follows:

     1.  Definitions.  Terms which are defined in the Loan Agreement and not
         -----------                                                        
otherwise defined herein are used herein as defined therein.  In addition to the
words and terms defined elsewhere in this Security Agreement, the following
words and terms shall have the following meanings, respectively, unless the
context otherwise clearly requires:

         (a)  "Code" shall mean the Uniform Commercial Code of each state as
enacted and in effect on the date hereof in each applicable jurisdiction, and as
the same may subsequently be amended from time to time.

         (b)  "Collateral" shall mean, all of Grantor's right, title and
interest in, to and under the following described property, whether now owned or
hereafter acquired (words and terms defined in the Code shall have the same
meanings when used herein):

              (i)  warrants to purchase 4,000,000 shares of the common stock of
Metromedia Asia Corporation (the "Warrants") which the Grantor now beneficially
owns or may hereafter acquire, as the same have been described in the
Termination Agreement (the "Termination Agreement"), dated September 11, 1996,
by and among Grantor, Metromedia Asia Corporation ("MAC"), as successor-in-
interest to Asian American Telecommunications Corporation and Max E. Bobbitt;
and

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              (ii) 2,000,000 shares (the "Shares") of the common stock of MAC
held beneficially and of record by Grantor, to the extent permissible under the
terms of the Termination Agreement, pursuant to which such shares are being held
in escrow until January 1, 1999.

                   The Shares and the Warrants collectively shall be referred to
as the "Securities". The term "Collateral" as it applies to the Shares and the
Warrants shall also include all rights and privileges pertaining thereto,
including, without limitation, all securities and additional securities
receivable in respect of or in exchange for such Securities, all rights to
subscribe for securities incident to or arising from ownership of such
Securities, all cash, interest, stock and other dividends or distributions paid
or payable on such Securities, and all books and records pertaining to the
foregoing, including, without limitation, all stock record and transfer books,
and whatever is received when any of the foregoing is sold, exchanged or
otherwise disposed of, including any proceeds as such term is defined in the
Code.

          (c)  "Secured Indebtedness" shall mean (i) all obligations, whether of
principal, interest, fees, expenses or otherwise, of Grantor to Lender, whether
now existing or hereafter incurred, under the Loan Agreement, Notes or any of
the Other Documents as any of the same may from time to time be amended,
modified or supplemented, together with any and all extensions, renewals,
refinancings or refundings thereof in whole or in part by the Lender, (ii) all
out-of-pocket costs, expenses and disbursements, including reasonable attorneys'
fees and legal expenses, incurred by the Lender in the collection of any of the
obligations referred to in subclause 1(c)(i) above; and (iii) any advances made,
subsequent to an Event of Default, by the Lender, for the reasonable
maintenance, preservation, protection or enforcement of, or realization upon,
the Collateral, including advances for taxes and the like and reasonable
expenses incurred to sell or otherwise realize on, or prepare for sale or other
realization on, any of the Collateral.

     2.  Assignment and Grant of Security Interests. As security for the due and
         ------------------------------------------
punctual payment and performance of the Secured Indebtedness in full, Grantor
hereby agrees that the Lender shall have, and Grantor hereby grants to and
creates in favor of the Lender, for the benefit of the Lender, to secure all of
the Secured Indebtedness, a continuing first priority security interest in and
to Grantor's Collateral; provided, however, that the security interest granted
in all of the Shares is subordinated to any security interest in the Shares
granted by the Grantor to MAC (the "Permitted Lien") pursuant to the Termination
Agreement.  Without limiting the generality of Section 4 below, Grantor further
agrees that with respect to each item of Collateral as to which (i) the creation
of valid and enforceable security interests is not governed exclusively by the
Code or (ii) the perfection of valid and enforceable security interests therein
under the Code cannot be accomplished by the Lender taking possession thereof or
by the filing in appropriate locations of appropriate Code financing statements
executed by the Grantor, Grantor will at its expense execute and deliver to the
Lender such documents, agreements, notices, assignments and instruments and take
such further actions as may be reasonably requested by the Lender from time to
time for the purpose of creating a valid and perfected first priority lien on
such item, enforceable against the Grantor and all third parties to secure the
Secured Indebtedness.

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     3.  Representations and Warranties.  Except as otherwise set forth in the
         ------------------------------                                       
Disclosure Statement attached as Exhibit B to the Loan Agreement, Grantor
represents, warrants and covenants to the Lender that:

         (a)  Grantor is the legal and beneficial owner and holder of the
Collateral and Grantor has and will continue to have good and marketable title
to the Collateral which Grantor purports to own or which is reflected as owned
in its books and records.

         (b)  The Grantor has received value from the Lender for Grantor's grant
of security interests hereunder and, except for the security interests granted
to and created in favor of the Lender hereunder, all of the Collateral is and
will continue to be free and clear of all liens, except the Permitted Lien.

         (c)  Grantor has full power to enter into, execute, deliver and carry
out this Security Agreement and to perform its obligations hereunder and all
such actions have been duly authorized by all necessary proceedings on its part.
This Security Agreement has been duly and validly executed and delivered by
Grantor. This Security Agreement constitutes the legal, valid and binding
obligations of Grantor, enforceable against it in accordance with its terms,
except to the extent that enforceability may be limited by bankruptcy,
insolvency, reorganization, moratorium or other similar laws affecting the
enforceability of creditors' rights generally or limiting the right of specific
performance.

         (d)  Neither the execution and delivery of this Security Agreement nor
compliance with the terms and provisions hereof (i) will conflict with or result
in any breach of the terms and conditions of the articles of incorporation,
bylaws or equivalent documents of Grantor or of any law or of the Termination
Agreement or any material agreement or instrument to which Grantor is a party or
by which it is bound or to which it is subject, (ii) will constitute a default
under any of the documents referred to in clause 3(d)(i) above or (iii) will
result in the creation or enforcement of any lien (other than the Permitted
Lien) whatsoever upon any Collateral (now or hereafter acquired) of Grantor.

     4.  Further Assurances. Grantor will, from time to time, at its expense,
         ------------------                                                  
faithfully preserve and protect the Lender's security interests in the
Collateral (other than the Shares) as continuing first priority perfected
security interests and the Lender's security interest in Grantor's Shares as a
continuing perfected security interest subordinate only to the Permitted Lien,
and will do all such other acts and things and will, upon request therefor by
the Lender, execute, deliver, file and record all such other documents and
instruments, including financing statements, security agreements, pledges,
assignments, documents and powers of attorney with respect to the Collateral,
and pay all filing fees and taxes related thereto as the Lender in its
reasonable discretion may deem necessary or advisable from time to time in
order to preserve, perfect or protect any security interest granted or purported
to be granted hereby or to enable the Lender to exercise and enforce its rights
and remedies hereunder with respect to any of the Collateral.  Without limiting
the generality of the foregoing, to the extent Article 9 of the Code does not
govern the creation and/or perfection of the security interests intended to be
created hereunder,

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Grantor agrees to execute and deliver such further documents and instruments and
do such further acts as the Lender may from time to time require.

     5.  Covenants. Grantor covenants and agrees that, except as otherwise 
         ---------
required by the Termination Agreement, (a) it will not sell, assign or otherwise
dispose of any portion of the Collateral; (b) it will obtain and maintain sole
and exclusive possession of its Collateral; (c) it will keep materially accurate
and complete books and records concerning the Collateral and such other books
and records as may be required under the Loan Agreement; (d) it will promptly
furnish to the Lender such information and documents relating to the Collateral
as the Lender may reasonably request in order to confirm the status of the
Lender's security interests in such Collateral; (e) it will not take or omit to
take any actions, the taking or the omission of which might result in a material
adverse alteration or impairment of the Collateral or in a violation of this
Security Agreement; (f) it will execute and deliver to the Lender and record
such supplements to this Security Agreement and additional assignments as the
Lender reasonably may request to evidence and confirm the security interests
herein contained; and (g) it will not agree to change, modify, extend or
terminate the Termination Agreement without the prior written consent of the
Lender. The Grantor shall notify the Lender in writing ten (10) days prior to
the effective date of any change or modification to, or extension or terminate
of, the Termination Agreement.

    6.  Preservation of Security Interests. Grantor assumes full responsibility 
        ----------------------------------
for taking and hereby agrees to take any and all necessary steps to preserve and
defend the Lender's right, title and security interests in and to the Collateral
against the claims and demands of all persons.  The Lender shall be deemed to
have exercised reasonable care in the custody and preservation of the Collateral
in the Lender's possession if, prior to the existence of an Event of Default,
the Lender takes such action for that purpose as such Grantor shall reasonably
request in writing, provided that such requested action will not, in the
                    --------                                            
judgment of the Lender, impair the security interests in the Collateral created
hereby or the Lender's rights in, or the value of, such Collateral, and provided
                                                                        --------
further that such written request is received by the Lender in sufficient time
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to permit the Lender to take the requested action.

    7.  Lender's Rights with Respect to the Collateral.  At any time and from 
        ---------------------------------------------- 
time to time, whether or not an Event of Default shall have occurred, and
without notice to or consent of the Grantor, the Lender may, at its option, do
any or all of the following: (a) do anything which the Grantor is required but
fails to do hereunder, and in particular the Lender may, if the Grantor fails to
do so, (i) insure or take any reasonable steps to protect the Collateral, (ii)
pay any or all taxes, levies, expenses and costs arising with respect to the
Collateral, or (iii) pay any or all premiums payable on any policy of insurance
required to be obtained or maintained hereunder, and add any amounts paid under
this Section 7 to the principal amount of the Loan Agreement, as evidenced by
the Notes, and other liabilities of Grantor secured by this Security Agreement;
(b) inspect the Collateral at any reasonable time; and (c) pay any amounts the
Lender reasonably elects to pay or advance hereunder on account of insurance,
taxes or other costs, fees or charges arising in connection with the Collateral,
either directly to the payee(s) of such cost, fee or charge, directly to the
Grantor, or to such payee(s) and Grantor, jointly.

                                       4
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     8.  Remedies on Default.  If there shall have occurred and be continuing an
         -------------------                                                    
Event of Default under the terms of the Loan Agreement, then the Lender shall,
subject to any restrictions set forth in the Termination Agreement, have such
rights and remedies with respect to the Collateral or any part thereof and the
proceeds thereof as are provided by the Code and such other rights and remedies
with respect thereto which it may have at law or in equity or under this
Security Agreement, including to the extent not inconsistent with the provisions
of the Code or any other applicable Law, the right to take over and collect the
Collateral which consists of amounts owing to Grantor to the extent not
prohibited by applicable law.  To this end, the Lender shall have the right to
(a) transfer all or any part of any of the Collateral into the Lender's name or
into the name of its nominee or nominees and thereafter receive all cash, stock
and other dividends or distributions paid or payable in respect thereof, and
otherwise act with respect thereto as the absolute owner thereof; (b) notify the
obligors on any of the Collateral, whether accounts or otherwise, to make
payment thereon directly to the Lender, whether or not the Grantor was
theretofore making collections thereon; (c) take control of and manage the
Collateral; (d) apply to the payment of the Secured Indebtedness, whether it be
due and payable or not, any moneys, including cash dividends and income from the
Collateral, now or hereafter in the hands of the Lender, on deposit or
otherwise, belonging to Grantor, in accordance with Section 9 hereof; (e)
endorse the name of the Grantor upon any checks or other evidences of payment or
any document or instrument that may come into the possession of the Lender as
proceeds of or relating to such Grantor's Collateral; (f) demand, sue for,
collect, compromise and give acquittances for the Collateral; (g) prosecute,
defend or compromise any action, claim or proceeding with respect to the
Collateral; and (h) take such other action as the Lender may deem appropriate,
including extending or modifying the terms of payment of the debtors of Grantor.
In addition, upon the occurrence of an Event of Default but subject to any
restrictions set forth in the Termination Agreement, Grantor, at the request of
the Lender, shall assemble all or any portion of the Grantor's Collateral at
such locations as the Lender shall designate which are reasonably convenient to
Grantor, and the Lender may sell, assign, give an option or options to purchase
or otherwise dispose of all or any part of the Collateral at any public or
private sale at such place or places and at such time or times and upon such
terms, whether for cash or on credit, and in such manner, as the Lender may
determine, and apply the proceeds so received in accordance with Section 9
hereof.  Written notice of sale mailed by certified mail, return receipt
requested, to the Grantor, at least ten (10) days prior to such sale shall be
deemed reasonable notice.

         In the event of a breach by Grantor in the performance of any of the
terms of this Security Agreement, the Lender may demand specific performance of
this Security Agreement and seek injunctive relief and may exercise any other
remedy, available at law or in equity, it being recognized that the remedies of
the Lender at law may not fully compensate the Lender for the damages it may
suffer in the event of a breach hereof.

     9.  Application of Proceeds. The proceeds of the Collateral shall be 
         -----------------------
applied in accordance with the terms of the Loan Agreement. Grantor shall be
liable for any deficiency if the proceeds of any sale, assignment, giving of an
option or options to purchase or other disposition of the Collateral is
insufficient to pay all amounts to which the Lender is entitled.

                                       5
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     10.  Attorneys-in-Fact.  After an Event of Default the Grantor hereby
          ----------------- 
irrevocably appoints the Lender, its officers, employees and agents, or any of
them, as attorneys-in-fact, with full power of substitution, for Grantor for the
purpose of carrying out the provisions of this Security Agreement and taking any
action and executing, delivering, filing and recording any instruments which the
Lender may deem necessary or advisable to accomplish the purposes hereof, which
power of attorney being given for security is coupled with an interest and
irrevocable. The Grantor hereby ratifies and confirms and agrees to ratify and
confirm all action taken by the Lender, its officers, employees or agents
pursuant to the foregoing power of attorney.

     11.  Indemnity and Expenses.
          ---------------------- 

          (a)  The Grantor unconditionally agrees to indemnify the Lender from
and against any and all claims, losses and liabilities arising out of or
resulting from this Security Agreement (including enforcement of this Security
Agreement), except claims, losses or liabilities resulting from the gross
negligence or willful misconduct of the Lender.

          (b)  The Grantor unconditionally agrees upon demand to pay to the
Lender the amount of any and all reasonable and necessary out-of-pocket costs,
expenses and disbursements, including fees and expenses of its counsel, which
the Lender may incur in connection with (i) the administration of this Security
Agreement, (ii) the custody, preservation, use or operation of, or the sale of,
collection from, or other realization upon, the Collateral, (iii) the exercise
or enforcement of any of the rights of the Lender hereunder or (iv) the failure
by the Grantor to perform or observe any of the provisions hereof.

     12.  Security Interest Absolute; Waiver of Notices. All rights of the
          --------------------------------------------- 
Lender hereunder, all security interests hereunder, and all obligations of the
Grantor hereunder shall be absolute and unconditional, irrespective of: (a) any
lack of validity or enforceability of the Loan Agreement, the Notes or any of
the Other Documents; (b) any change in the time, manner or place or payment of,
or in any other term of, all or any of the Secured Indebtedness or any other
amendment or waiver of or any consent to any departure from the Loan Agreement,
the Notes or any of the Other Documents; (c) any exchange, release or non-
perfection of any other Collateral; or (d) any other circumstance which might
otherwise constitute a defense available to, or a discharge of, any Grantor or
any third party mortgagors, pledgors or grantors of security interests. Grantor
waives any and all notice with respect to acceptance by the Lender of this
Security Agreement, the provisions of the Loan Agreement, the Notes or any of
the Other Documents or any other note, instrument or agreement relating to the
Secured Indebtedness, and any default in connection with the Secured
Indebtedness. Grantor waives any presentment, demand, notice of dishonor or
nonpayment, protest, notice of protest and any other notice of any kind in
connection with the Secured Indebtedness.

     13.  Termination.  Upon payment in full of the Secured Indebtedness and
          -----------                                                       
termination of the Loan Agreement and the Notes, this Security Agreement shall
terminate and be of no further force and effect, and the Lender, at the
Grantor's expense, shall thereupon promptly return to Grantor the Collateral and
such other documents delivered by Grantor hereunder as may

                                       6
<PAGE>
 
then be in the Lender's possession. Upon any such termination, the Lender will,
at the Grantor's expense, execute and deliver to the Grantor such documents as
that Grantor shall reasonably request to evidence such termination.

     14.  Modifications, Amendments and Waivers. Any and all agreements amending
          -------------------------------------
or changing any provision of this Security Agreement or the rights of any of the
Lender or the Grantor, and any and all waivers or consents to Events of Default
or other departures from the due performance of the Grantor hereunder shall be
made only pursuant to the provisions of Section 7 of the Loan Agreement.

     15.  No Implied Waivers; Cumulative Remedies.  No course of dealing and no
          ---------------------------------------                              
failure or delay on the part of the Lender in exercising any right, remedy,
power or privilege hereunder shall operate as a waiver thereof or of any other
right, remedy, power or privilege of the Lender hereunder; and no single or
partial exercise of any such right, remedy, power or privilege shall preclude
any other or further exercise thereof or the exercise of any other right,
remedy, power or privilege.  The rights and remedies of the Lender under this
Security Agreement are cumulative and not exclusive of any rights or remedies
which it may otherwise have.

     16.  Notices.  All notices, statements, requests, demands and other
          -------                                                       
communications given to or made upon the Grantor, the Lender in accordance with
the provisions of this Security Agreement shall be given or made as provided in
Section 7 of the Loan Agreement.

     17.  Severability.
          ------------ 

          (a)  Grantor agrees that the provisions of this Security Agreement are
severable, and in an action or proceeding involving any state or federal
bankruptcy, insolvency or other law affecting the rights of creditors generally:

               (i)   if any clause or provision shall be held invalid or
unenforceable in whole or in part in any jurisdiction, then such invalidity or
unenforceability shall affect only such clause or provision, or part thereof, in
such jurisdiction and shall not in any manner affect such clause or provision in
any other jurisdiction, or any other clause or provision in this Agreement in
any jurisdiction;

               (ii)  if this Security Agreement would be held or determined to
be void, invalid or unenforceable on account of the amount of the aggregate
liability of Grantor under this Security Agreement, then, notwithstanding any
other provision of this Security Agreement to the contrary, the aggregate amount
of such liability shall, without any further action by the Lender, Grantor or
any other person, be automatically limited and reduced to the highest amount
which is valid and enforceable as determined in such action or proceeding.

               (iii) If the grant of any security interest hereunder by Grantor
is held or determined to be void, invalid or unenforceable, in whole or in part,
such holding or determination shall not impair or affect the validity and
enforceability of any clause or provision not so held to be void, invalid or
unenforceable.

                                       7
<PAGE>
 
     18.  Governing Law.  This Security Agreement shall be deemed to be a
          ------------- 
contract under the laws of the State of Delaware and for all purposes shall be
governed by and construed in accordance with the internal laws of said State,
without reference to its conflicts of law principles, except as required by
mandatory provisions of law and except to the extent that the validity or
perfection of security interests hereunder, or remedies hereunder with respect
to the Collateral, is governed by the laws of a jurisdiction other than the law
of the State of Delaware.

     19.  Successors and Assigns.  This Security Agreement shall be freely 
          ----------------------
assignable and transferable by the Lender in connection with the assignment or
transfer of the Secured Indebtedness; provided, however, the duties and
                                      --------  -------
obligations of the Grantor may not be delegated or transferred by the Grantor,
without the written consent of the Lender. The rights and privileges of the
Lender shall inure to their benefit and the benefit of its respective successors
and assigns (as permitted under the Loan Agreement) and the duties and
obligations of the Grantor shall bind the Grantor and its respective successors
and assigns.

     20.  Counterparts. This Security Agreement may be executed in any number of
          ------------
counterparts and by the different parties hereto on separate counterparts, each
of which, when so executed and delivered, shall be deemed an original, but all
such counterparts shall constitute but one and the same instrument.

     21.  Consent to Jurisdiction; Waiver of Jury Trial. The Grantor hereby
          ---------------------------------------------                    
irrevocably consents to the exclusive jurisdiction of the courts of the
Commonwealth of Pennsylvania located within Philadelphia County and the United
States District Court for the Eastern District of Pennsylvania and waives
personal service of any and all process upon it and consents that all such
service of process be made by certified or registered mail directed to the
Grantor at the addresses set forth or referred to in Section 16 hereof and
service so made shall be deemed to be completed upon actual receipt thereof.
The Grantor waives any objection to jurisdiction and venue of any action
instituted against it as provided herein and agrees not to assert any defense
based on lack of jurisdiction or venue, AND THE LENDER WAIVES TRIAL BY JURY IN
ANY ACTION, SUIT, PROCEEDING OR COUNTERCLAIM WITH RESPECT TO THIS SECURITY
AGREEMENT TO THE FULL EXTENT PERMITTED BY LAW.

     WITNESS the due execution hereof as of the day and year first above
written.

                                       PORTACOM WIRELESS, INC.

                                        BY:  /s/ Douglas C. MacLellan
                                             ------------------------
                                        Douglas C. MacLellan,
                                        President and Chief Executive Officer


                                       VDC CORPORATION LTD.

                                        BY:  /s/ Graham Ferguson Lacey
                                             -------------------------
                                        Graham Ferguson Lacey, President
 
                                       8