SECURITY AGREEMENT
                               ------------------

     THIS SECURITY  AGREEMENT  ("Agreement")  is made and entered into this 20th
day of  April,  2000,  by and  between  VDC  Communications,  Inc.,  a  Delaware
corporation ("Secured Party"), and Network Consulting Group, Inc., ("Pledgor").

     RECITALS
     --------

     A. Concurrently  herewith,  Rare  Telephony, Inc. (f/k/a/ Washoe Technology
Corporation)  and Cash Back Rebates LD.com,  Inc.  ("Borrower")  have executed a
certain  Promissory  Note (the  "Note")  in the stated  principal  amount of Two
Hundred Thousand Dollars ($200,000) in favor of the Secured Party.

     B. Also  concurrently  herewith,  Pledgor has  executed in favor of Secured
Party a certain Guaranty  Agreement (the  "Guaranty")  pursuant to which Pledgor
has guaranteed the indebtedness of Borrower, to Secured Party under the Note.

     C. The  indebtedness  of Pledgor to the Secured Party under the Guaranty is
hereinafter collectively referred to as the "Indebtedness".

     D. It is the purpose and intent of the parties hereto to secure the payment
by  Pledgor  to  Secured  Party  of the  Indebtedness  by a  pledge  of  certain
collateral, according to the terms and conditions set forth herein.

     NOW,  THEREFORE,  in consideration of the premises and the mutual covenants
and conditions set forth herein, the parties agree as follows:

     1. Pledgor  hereby  grants to Secured  Party a security  interest in and to
6,250  shares  of the  common  stock  of Rare  Telephony,  Inc.  (f/k/a/  Washoe
Technology  Corporation) evidenced by Share Certificate No. 8 ("Collateral") and
does hereby deliver to and deposit the Collateral  with Secured Party,  together
with a stock power duly executed in blank.

     During the term hereof,  and subject to the  provisions of this  Agreement,
Secured Party shall hold and retain the Collateral for the purpose of perfecting
the security  interest  herein granted to Secured Party,  and for the purpose of
carrying out the provisions of this Agreement.

     2. The Collateral shall secure the payment of the Indebtedness.

     3. Pledgor warrants that Pledgor is the sole lawful owner of the Collateral
and that there is no lien or charge against, or encumbrance or security interest
in, or adverse claim to, the Collateral,  or any portion thereof, other than the

                                       1
<PAGE>

security  interest created  pursuant to this Agreement.  So long as there is any
Indebtedness  whatsoever  owing to  Secured  Party,  Pledgor  agrees to keep the
Collateral free and clear of any and all liens, encumbrances, security interests
(other  than  the  security  interest  of  Secured  Party),  adverse  claims  or
interests.

     4. As  long  as  Pledgor  is not in  default  hereunder,  any and all  cash
dividends or other property (but not stock  dividends)  which may be received by
Secured  Party  during  the  term of  this  Agreement  which  derives  from  the
Collateral  shall be remitted to Pledgor,  and Pledgor  shall  retain all voting
rights  associated  with the  Collateral.  Any cash  dividends or other property
received  with  respect  to the  Collateral  after the  occurrence  of a default
hereunder  shall  be  delivered  to and  held by  Secured  Party  as  additional
Collateral,  and after the  occurrence of such default  Secured Party shall have
all voting rights associated with the Collateral.

     5. Pledgor shall be in default under this  Agreement  upon the happening of
any of the following events:

              (a) Pledgor fails to pay any portion of the Indebtedness when due;

              (b) Borrower commits a default under the Note or Pledgor commits a
default under the Guaranty;

              (c) Pledgor fails to perform any other agreement or covenant under
this Agreement  within any applicable  notice and/or "grace"  periods  specified
herein, provided that if no notice or grace period is herein specified,  Pledgor
shall have ten (10)  calendar  days after  notice  thereof has been given within
which to cure any such default;

              (d) All or a majority of the value of the Collateral or the assets
of  Borrower  is  seized  or  levied  upon by writ of  attachment,  garnishment,
execution or otherwise,  and such seizure or levy is not released  within thirty
(30) calendar days thereafter;

              (e) Either Pledgor or Borrower  executes a general  assignment for
the benefit of its  creditors,  convenes any meeting of its  creditors,  becomes
insolvent, admits in writing its insolvency or inability to pay its debts, or is
unable to pay or is generally not paying its debts as they become due;

              (f) A receiver,  trustee,  custodian or agent is appointed to take
possession  of all or any portion of the  Collateral  or all or any  substantial
potion of Pledgor's or Borrower's assets;

                                       2
<PAGE>

              (g) Any case or proceeding is voluntarily  commenced by Pledgor or
Borrower under any provision of the federal Bankruptcy Code or any other federal
or  state  law  relating  to  debtor  rehabilitation,   insolvency,  bankruptcy,
liquidation, or reorganization,  or any such case or proceeding is involuntarily
commenced  against  Pledgor or Borrower  and not  dismissed  within  thirty (30)
calendar days thereafter;

              (h) Any representation made by Pledgor in this Agreement or in any
of the other documents delivered in connection therewith, shall have been untrue
or incorrect in any material respect when made.

     Upon  such  default,   Secured  Party  may,  at  its  option,  declare  all
Indebtedness  to be  immediately  due and payable.  Additionally,  Secured Party
shall have the rights and remedies set forth in Paragraph 6 below.

     6. Should Pledgor  default under this  Agreement,  Secured Party shall have
all rights and remedies  afforded a secured  party under the Uniform  Commercial
Code of New Jersey and may, in connection therewith, also:

              (a) Sell,  lease, or otherwise dispose of the Collateral at public
or private sale, in one or more sales, as a unit or in parcels,  at wholesale or
retail,  and at such  time and  place  and on such  terms as  Secured  Party may
determine. Secured Party may be the purchaser or any or all of the Collateral at
any public or private sale.  If, at any time when Secured Party shall  determine
to  exercise  its  right  to sell  all or any  part of the  Collateral  and such
Collateral, or the part thereof to be sold, it has been advised by legal counsel
that the  Collateral is subject to the  Securities Act of 1933 as amended or any
state securities  laws,  Secured Party in its sole and absolute  discretion,  is
hereby  expressly  authorized  to sell  such  Collateral,  or any part  thereof,
subject to obtaining all required regulatory approvals,  by private sale in such
manner  and under such  circumstances  as Secured  Party may deem  necessary  or
advisable in order that such sale may be effected  legally without  registration
or  qualification  under  applicable   securities  laws.  Without  limiting  the
generality of the foregoing,  Secured Party, in it sole and absolute discretion,
may approach and negotiate with a restricted  number of potential  purchasers to
effect such sale or  restrict  such sale to a purchaser  or  purchaser  who will
represent and agree that such  purchaser or purchasers are purchasing for his or
their own account,  for investment only, and not with a view of the distribution
or sale of such Collateral or any part thereof. Any such sale shall be deemed to
be a sale made in a  commercially  reasonable  manner  within the meaning of the
Uniform  Commercial  Code of the State of New Jersey and Pledgor hereby consents
and agrees that Secured  Party shall incur no  responsibility  or liability  for
selling all or any part of the  Collateral at a price which is not  unreasonably
low,  notwithstanding  the possibility  that a higher price might be realized if

                                       3
<PAGE>

the sale were  public.  Any public sale of any or all of the  Collateral  may be
postponed  from time to time by public  announcement  at the time and place last
scheduled for the sale.  Without  limiting the  generality of this Section 6, it
shall conclusively be deemed to be commercially  reasonable for Secured Party to
direct any  prospective  purchaser of any or all of the Collateral to Pledgor to
ascertain all information  concerning the status of Borrower.  Securing  Party's
disposition of any or all of the Collateral in any manner which differs from the
procedures  specified in this  Section 6 shall not be deemed to be  commercially
unreasonable; or

         (b)  Propose  to accept  the  Collateral  after  giving  notice of such
proposal  to Pledgor  and to any other  person  with a security  interest in the
Collateral in accordance with the Uniform  Commercial Code of New Jersey, or any
applicable successor statute.  Such acceptance shall discharge the obligation of
Pledgor and the  Corporation  with respect to the  Indebtedness,  provided  that
neither Pledgor nor any other person with a security  interest in the Collateral
objects in writing to such a proposal within twenty one (21) calendar days after
receipt of such notice.

     The  proceeds of any sale,  lease or other  disposition  of the  Collateral
shall be applied in the manner and priority set forth in the Uniform  Commercial
Code of New Jersey, or any applicable successor statute.

     7. Pledgor  unconditionally  agrees upon demand to pay to the Secured Party
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 Secured
Party may incur in connection  with (i) the  administration  of this  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  Secured  Party  hereunder  or (iv) the
failure by Pledgor to perform or observe any of the provisions  hereof.  Pledgor
unconditionally  agrees to indemnify  the Secured Party from and against any and
all  claims,  losses  and  liabilities  arising  out of or  resulting  from this
Agreement (including  enforcement of this Agreement),  except claims,  losses or
liabilities  resulting  from the gross  negligence or willful  misconduct of the
Secured Party.

     8. Pledgor waives any right to require the Secured Party to:

              (a) Proceed against any person;

              (b) Proceed against or exhaust any collateral; or

              (c) Pursue any other remedy in Secured Party's power.

                                       4
<PAGE>

     Pledgor further authorizes the Secured Party,  without notice or demand and
without affecting its liability  hereunder or on the Indebtedness,  from time to
time to:

         (d)  Amend  or  modify  the  terms  of the  Note or the  Guaranty  with
Pledgor's  consent,  including,  but not  limited  to,  any  such  amendment  or
modification which affects the Indebtedness.

         (e) Take and hold security, other than the Collateral herein described,
for the payment of the Indebtedness or any part thereof, and exchange,  enforce,
waive,  and release the Collateral  herein  described or any part thereof or any
such other security.

         (f) Apply such  Collateral  or other  security  and direct the order or
manner of sale thereof as Secured Party in its discretion may determine.

     9. In the event that any additional shares of capital stock of Borrower are
issued  to or  acquired  by  Pledgor  during  the term of this  Agreement,  such
additional  shares shall be  considered  additional  Collateral  subject to this
Agreement,  and Pledgor shall immediately deliver stock certificates  evidencing
such  additional  shares of  capital  stock and duly  executed  stock  powers to
Secured Party.

     10. Neither the acceptance of any partial or delinquent  payment by Secured
Party nor Secured  Party's  failure to exercise any of its rights or remedies on
default by Pledgor  shall be a waiver of the  default,  a  modification  of this
Agreement  or Pledgor's  obligations  under this  Agreement,  or a waiver of any
subsequent default by Pledgor.

     11. All notices  are  required or  permitted  to be given  pursuant to this
Agreement  shall be in writing,  and shall be delivered  either  personally,  by
overnight  delivery  service or by U.S.  certified or registered  mail,  postage
prepaid,  return-receipt  requested  and  addressed  to  the  parties  at  their
respective  addresses as the appear below their signatures  hereon.  Notices may
also be given by facsimile transmission to the facsimile telephone numbers which
appear below the parties' respective signatures hereon, provided that either (a)
receipt  of  the  facsimile  transmission  is  acknowledged  in  writing  by the
receiving party,  which may also be by a facsimile  transmission is acknowledged
in writing by the receiving party, which may also be by facsimile  transmission,
or (b) the  transmitting  party  obtains  a  written  confirmation  from its own
facsimile  machine showing that the entire  transmission  was transmitted to the
receiving  party.  The parties  may also change  their  addresses  or  facsimile

                                       5
<PAGE>

telephone  numbers for notice by giving notice of such change in accordance with
this  section.  Notices  sent by  overnight  delivery  service  shall be  deemed
received on the  business  day  following  the date of deposit with the delivery
service. Mailed notices shall be deemed received upon the earlier of the date of
delivery shown on the return-receipt,  or the second business day after the date
of mailing. Notices sent by facsimile transmission shall be deemed served on the
date of  transmission,  provided  that all such notices are sent during  regular
business hours, otherwise on the next business day.

     12.  Time  is  hereby  expressly  declared  to be of the  essence  of  this
Agreement.

     13.  This  Agreement  and each of its  provisions  shall be  binding on the
heirs, executors, administrators, successors, and assigns of each of the parties
hereto.

     14.  This Agreement  is made and entered into and shall be  interpreted  in
accordance with the laws of the State of New Jersey.  Any action concerning this
Agreement  shall be commenced in a court of competent  jurisdiction in the State
of New Jersey.

     15.  Upon payment in full of the portion of  Indebtedness  evidenced by the
Note, this Agreement shall terminate and be of no further force or effect.  Upon
receipt of satisfactory  proof from both parties in writing that such portion of
the Indebtedness has been paid in full, Secured Party shall immediately  deliver
to Pledgor the Collateral and the stock powers.

     16.  Secured Party shall not be  responsible  for any damage of loss to the
Collateral, or any part thereof, arising from an act of God, flood, fire, or any
other cause beyond the reasonable control of Secured Party.

     17. Upon the request of Secured Party, from time to time, Pledgor agrees to
execute,  acknowledge  and deliver,  or cause to be executed,  acknowledged  and
delivered,  all such additional  instruments,  and agrees to perform any and all
acts reasonably  required to carry into effect the provisions and intent of this
Agreement.

     IN WITNESS WHEREOF, the parties have executed this Agreement on the day and
year first above written.


WITNESS:                                     "PLEDGOR"


/s/ Debra A. Santa Lucia                     /s/ Peter J. Salzano
------------------------                     --------------------
Signature





                                       6
<PAGE>

Peter J. Salzano /s/ Peter J. Salzano        74 Jesse Court
-------------------------------------        Montville, NJ  07045
Print Name                                   Facsimile No. 973-822-8520
                                                          -------------



ATTEST:                                      "SECURED PARTY"


/s/ Louis D. Frost                           VDC COMMUNICATIONS, INC.
------------------
Signature


                                             By:  /s/ Frederick A. Moran
                                                -------------------------
Louis D. Frost                                    Frederick A. Moran
--------------                                    Chief Executive Officer
Print Name
                                             75 Holly Hill Lane
                                             Greenwich, CT  06830
                                             Facsimile No. (203) 552-0908

                                       7