FIRST AMENDMENT TO
                           LOAN AND SECURITY AGREEMENT

                  This First  Amendment  to Loan and  Security  Agreement  (this
"Amendment")  is made and entered into effective as of the 15th day of December,
1999,  by  and  between  FINOVA  Capital  Corporation,  a  Delaware  corporation
("Lender"),  and Datatec Industries Inc., a New Jersey corporation ("Borrower").
This  Amendment is joined in by Datatec  Systems,  Inc., a Delaware  corporation
formerly known as Glasgal Communications,  Inc. ("Parent"), which is a guarantor
and holder and pledgor of 100% of the issued and outstanding  stock of Borrower,
and by HH  Communications,  Inc., an Illinois  corporation  ("HHC"),  which is a
guarantor.  In addition,  this Amendment is joined in by Computer-Aided Software
Integration,   Inc.,   a  Delaware   corporation   ("CASI"),   to  document  its
participation in the transaction, as described below.

                                R E C I T A L S :

                  WHEREAS,  Lender and  Borrower  entered into that certain Loan
and  Security  Agreement  dated as of March  17,  1997 (the  "Loan  Agreement"),
pursuant to which Lender made available to Borrower loans in the amount of up to
$17,000,000  (the  "Loan"),  consisting  of a senior  term loan in the amount of
$2,000,000  (the "Term Loan") and a revolving line of credit in the amount of up
to $15,000,000 (the "Revolving Loans  Facility"),  upon the terms and conditions
set forth in the Loan  Agreement.  All terms used  herein with  initial  capital
letters,  unless  otherwise  specifically  defined  herein,  shall have the same
meanings as set forth in the Loan Agreement; and

                  WHEREAS,  Borrower  has  requested  that Lender amend the Loan
Agreement to provide  Borrower with a temporary  line of credit in excess of the
maximum  amount  permitted  by the  advance  ratios  under the  Revolving  Loans
Facility (the  "Overadvance") in the amount of up to $1,000,000 (such additional
$1,000,000  being  referred to herein as the  "Temporary  Overadvance  Amount"),
which  Overadvance would be effective for a period commencing on the date hereof
through and  including  February  15,  2000 (the  "Overadvance  Term"),  but not
thereafter; and

                  WHEREAS,  the Revolving Loans Facility is presently secured by
the Collateral as described in the Loan Agreement; and

                  WHEREAS, Lender is willing to enter into this Amendment and to
make available the Temporary  Overadvance  Amount for the Overadvance Term, upon
the terms and conditions set forth herein.

                  NOW, THEREFORE, in consideration of the foregoing premises and
the mutual covenants  hereinafter  stated, the parties hereto do hereby agree as
follows:


<PAGE>

                  1. Overadvance Availability.  Effective as of the date hereof,
and  notwithstanding  anything  set forth in Section 1.2 of the  Schedule to the
Loan Agreement to the contrary, the Temporary Overadvance Amount, in addition to
the Loans  described  in the Loan  Agreement,  shall be  available  to  Borrower
throughout the Overadvance  Term.  Borrower may request  advances of portions of
the Temporary  Overadvance Amount,  provided however, that in no event shall the
aggregate of advances in excess of the Loans  provided for in the Loan Agreement
at any time be permitted to exceed the Temporary  Overadvance  Amount, nor shall
total Advances, inclusive of the Temporary Overadvance Amount, ever be permitted
to exceed the Maximum Amount. Advances of the Temporary Overadvance Amount shall
be made available to Borrower  without  regard to the percentage  limitations on
advances  set forth in Section 1.2 of the Loan  Agreement  (with the result that
Borrower  shall  be  permitted  to be  "out  of  formula"  as to  the  Temporary
Overadvance  Amount).  All  advances of portions  of the  Temporary  Overadvance
Amount shall be considered Advances under the Loan Agreement.

                  2. Expiration of Overadvance  Term. As an express condition to
Lender's agreements as set forth herein, Borrower specifically acknowledges that
upon the  expiration of the  Overadvance  Term,  the maximum  permitted  amounts
outstanding under the Revolving Loans Facility,  as each such term is defined in
the Loan Agreement,  shall be reduced to the amounts set forth therein,  and any
portion of the Temporary Overadvance Amount outstanding as of February 15, 2000,
shall immediately be due and payable.

                  3. Early Expiration of the Overadvance  Term.  Notwithstanding
the provisions of Section 2 hereof, the Temporary  Overadvance Amount may become
unavailable to Borrower at an earlier time in the following  circumstance.  Upon
the occurrence of any Event of Default, Lender shall be entitled, at its option,
to immediately  terminate the availability of the Temporary  Overadvance  Amount
(such  termination  to be without  prejudice to Lender in exercising any and all
other rights and remedies as set forth in the Loan  Agreement and the other Loan
Documents),  at which time no  further  advances  in  respect  of the  Temporary
Overadvance  Amount shall be available to Borrower and all outstanding  advances
of the Temporary Overadvance Amount shall become immediately due and payable.

                  4.  Representations  and  Warranties  of  Borrower.  To induce
Lender to enter into this Amendment,  and  acknowledging  Lender's reliance upon
the truth and accuracy  thereof,  Borrower  represents and warrants to Lender as
follows:

                  (a) Borrower has the requisite  corporate  power and corporate
         authority  to  enter  into  this   Amendment   and  the  documents  and
         instruments to be executed in connection  herewith,  and to perform its
         obligations hereunder and thereunder.

                                      -2-

<PAGE>

                  (b) This  Amendment and any other  documents  and  instruments
         executed  and  delivered to Lender by Borrower in  connection  herewith
         were duly authorized by all requisite  corporate  action on the part of
         Borrower  and  with  any   requirements   of  Borrower's   articles  of
         incorporation  and  bylaws,  and  any  amendments  thereto,   and  this
         Amendment and any other documents or instruments executed in connection
         herewith have been duly executed and delivered by Borrower.

                  (c) The execution  and delivery by Borrower of this  Amendment
         and any other instruments  executed and delivered by Borrower to Lender
         in  connection  herewith,  and the full  and  complete  performance  by
         Borrower of the provisions hereof, will not result in any breach of, or
         constitute  a  default  under,  or,  except  as  contemplated  by  this
         Amendment,  result in the creation of any lien,  charge or  encumbrance
         upon any property or assets of Borrower under any indenture,  mortgage,
         deed of  trust,  bank  loan  or  credit  agreement  or  other  material
         instrument to which Borrower is a party or by which Borrower is bound.

                  (d) This Amendment is the legal,  valid and binding obligation
         of Borrower, enforceable against Borrower in accordance with its terms,
         except that the  enforceability  hereof may be subject to or limited by
         bankruptcy,  insolvency,  reorganization,  arrangement,  moratorium, or
         other similar laws relating to or affecting  creditors  generally,  and
         general principles of equity.

                  (e) All of the respective  representations and warranties made
         by the Borrower in any of the Loan Documents remain true,  complete and
         correct  as of the date  hereof,  unless  they  expressly  relate to an
         earlier date.

                  5. Joinder By CASI. As of the original  Closing Date,  certain
circumstances  prevented CASI from both (i ) joining in the Loan  Agreement,  in
the manner which had  previously  been  contemplated  by the  parties,  and (ii)
benefiting from certain provisions thereof in the manner being enjoyed by Parent
and HHC.  Those  circumstances  have now  terminated,  and CASI wishes to obtain
certain  benefits under the Loan  Agreement.  Accordingly,  CASI hereby joins in
this  Amendment for the purpose of obtaining  such  benefits.  To the extent the
Loan Agreement  contains  provisions  which purport to extend to and bind any of
the other Loan Parties,  CASI hereby adopts and agrees to be bound by such terms
and  provisions  of the Loan  Agreement,  and  hereby  makes  and  delivers  all
representations,  warranties,  and  covenants  in favor of Lender which by their
terms extend to the Loan Parties or any of them. On or before  January 15, 2000,
CASI shall execute and deliver, in form and substance  satisfactory to Lender, a
Continuing Guaranty, Promissory Note in an amount of up to $______________,  and
Guarantor  Security  Agreement  which  are in form and  substance  substantially
identical  to those  executed and  delivered  by HHC as of the original  Closing
Date. In addition,  CASI shall execute and deliver such further  instruments  as
Lender may reasonably  request in order to effectuate the original intent of the
Parties that CASI  participate in the  transaction in the same manner as HHC. In
connection


                                      -3-

<PAGE>

with the  foregoing,  on or before  January 15, 2000,  Parent shall  execute and
deliver a Stock Pledge Agreement  pledging in favor of Lender the CASI Stock, in
form  and  substance  substantially  identical  to the  Stock  Pledge  Agreement
pursuant  to which  Parent  pledged  the HHC  Stock in  favor of  Lender  at the
original Closing.

                  6.  Release of Lender.  As  additional  consideration  for the
agreements  by  Lender  as set  forth in this  Amendment,  Borrower,  except  as
otherwise provided in the next sentence,  hereby releases and forever discharges
Lender,  its  agents,  servants,  employees,   directors,  officers,  attorneys,
branches,  affiliates,  subsidiaries,  successors  and assigns and all  persons,
firms,  corporations,  and organizations acting or serving in its behalf, of and
from all damage, loss, claims, demands,  liabilities,  obligations,  actions and
causes of action whatsoever which Borrower may now have or claim to have against
Lender,  whether  presently  known or  unknown,  and of every  nature and extent
whatsoever on account of or in any way touching,  concerning,  arising out of or
founded  upon the  Loans,  any of the Loan  Documents  or upon  this  Amendment,
including  without  limitation  all such loss or  damage of any kind  heretofore
sustained,  or that may  arise as a  consequence  of the  dealings  between  the
parties. The release set forth above shall not extend to any claim arising after
the date hereof to the extent  based on acts or  omissions  of Lender  occurring
after such  date,  except  that such  release is  specifically  intended  by the
parties to include all dealings of the parties  leading to the  consummation  of
the transaction contemplated by this Amendment. This Amendment and the covenants
contained in this Section 6 are  contractual,  and not a mere  recital,  and the
parties hereto acknowledge and agree that no liability whatsoever is admitted on
the part of any party,  except as provided  for by the Loan  Documents  and this
Amendment.

                  7. Fees and  Expenses.  Borrower  shall pay to Lender a fee in
the amount of $15,000  (the  "Overadvance  Fee") in  consideration  for Lender's
agreement to make the  Overadvance  available to Borrower.  The  Overadvance Fee
shall be due and payable in full upon the  expiration of the  Overadvance  Term.
Borrower  shall also pay, on demand,  all costs and  expenses  arising  from the
preparation of this Amendment, including Lender's reasonable attorneys' fees and
all of Lender's and its attorneys'  out-of-pocket costs and expenses incurred in
connection  with the negotiation and  documentation  of this Amendment,  and any
other costs, expenses or charges that may be imposed on or incurred by Lender as
a result of this  Amendment.  Lender  shall have the right to withhold  from any
Advance made hereunder any such costs, fees,  expenses or reimbursements due and
owing to Lender.

                  8.  Confirmation  of  Security   Interests.   Borrower  hereby
confirms and agrees that Lender's  security  interest in and to the  Collateral,
all as more specifically granted pursuant to the Loan Agreement, shall remain in
full force and effect until the Loans have been paid in full to Lender.

                  9. No Waiver of Defaults.  This  Amendment in no way acts as a
waiver of any future  default of  Borrower  except as  specifically  agreed upon
herein  or as a  release  or  relinquishment  of  any  of  the  liens,  security
interests,  rights  or  remedies  securing  payment  of

                                      -4-


<PAGE>

the Loans or for the enforcement  thereof,  including,  without limitation,  the
liens  created by the other Loan  Documents.  Such  liens,  security  interests,
rights and  remedies  are hereby  ratified,  confirmed,  preserved,  renewed and
extended by Borrower in all respects.

                  10. Benefit of the Amendment. The terms and provisions of this
Amendment  and the other Loan  Documents  shall be binding upon and inure to the
benefit of Lender and  Borrower  and their  respective  successors  and assigns,
except that  Borrower  shall not have any right to assign its rights  under this
Amendment or any of the Loan Documents or any interest therein without the prior
written consent of Lender.

                  11. Choice of Law. The Loan Documents and this Amendment shall
be performed and construed in accordance with the laws of the State of Arizona.

                  12. Entire  Agreement.  Except as modified by this  Amendment,
the Loan  Documents  remain in full  force and  effect.  The Loan  Documents  as
modified by this Amendment embody the entire agreement and understanding between
Borrower and Lender,  and  supersede  all prior  agreements  and  understandings
between said parties relating to the subject matter thereof.

                  13.   Counterparts;   Telecopy   Execution.   This   Amendment
(including  the  Consents  hereto)  may be  executed  in any number of  separate
counterparts,  each of which, when taken together,  shall constitute one and the
same  agreement,  admissible  into evidence,  notwithstanding  the fact that all
parties  have  not  signed  the  same  counterpart.   Delivery  of  an  executed
counterpart of this Amendment by telefacsimile  shall be equally as effective as
delivery  of a  manually  executed  counterpart  of this  Amendment.  Any  party
delivering an executed counterpart of this Amendment by telefacsimile shall also
deliver a manually  executed  counterpart of this Amendment,  but the failure to
deliver  a  manually  executed   counterpart  shall  not  affect  the  validity,
enforceability, and binding effect of this Amendment.


                                      -5-

<PAGE>

                  IN WITNESS  WHEREOF,  the parties  hereto have  executed  this
Amendment effective as of the day, month, and year first above written.

                                       FINOVA CAPITAL CORPORATION, a Delaware
                                       corporation


                                       By:
                                          --------------------------------------
                                          Name:
                                          Title:


                                       DATATEC INDUSTRIES INC., a New Jersey
                                       corporation


                                       By:
                                          --------------------------------------
                                          Name:
                                          Title:

                  This Amendment is executed by the  undersigned for purposes of
agreeing to and adopting the provisions set forth in Section 5 thereof.

                                       COMPUTER-AIDED SOFTWARE INTEGRATION,
                                       INC., a Delaware corporation


                                       By:
                                          --------------------------------------
                                          Name:
                                          Title:




<PAGE>

                 CONSENT AND AGREEMENT OF PLEDGOR AND GUARANTORS

                  The undersigned ("Guarantors") hereby consent to the making of
the foregoing First Amendment to Loan and Security  Agreement (the  "Amendment")
and agree that,  notwithstanding  the extension of the  additional  Indebtedness
represented by the Temporary  Overadvance Amount, and the other modifications to
the Loan  Documents  described  in the  Amendment,  (a) each of the Stock Pledge
Agreements by Parent in favor of Lender,  dated as of March 17, 1997 (the "Stock
Pledge Agreements"), remain in full force and effect; (b) each of the Guaranties
made by  Guarantors  in  favor  of  Lender,  dated as of  March  17,  1997  (the
"Guaranties")  remain in full force and effect;  (c) the Borrower's  Obligations
referred  to in the  Guaranties  shall  include all  advances  of the  Temporary
Overadvance  Amount,  and all accrued  interest or costs and expenses payable to
Lender in  connection  therewith;  and (d)  Guarantors  do not have any  offset,
defense  or  counterclaim  with  respect  thereto,  no claim or  defense  in the
abatement or reduction of such  Indebtedness,  or any other claim against Lender
or with respect to any document  forming part of the  transaction  in respect of
which the Stock Pledge  Agreements and the Guaranties  were made or forming part
of any other  transaction  under  which  Borrower  is  indebted  to Lender.  The
undersigned  are  executing  this  Consent for the purpose of  consummating  the
transaction  contemplated by the Amendment,  and this Consent is not intended to
be an amendment or  modification of any of the terms and provisions of the Stock
Pledge Agreements or the Guaranties, except to the extent of confirming that all
amounts  due to  Lender in  respect  of the  Temporary  Overadvance  Amount  are
included  within  the scope of the  Borrower's  Obligations  as  defined  in the
Guaranties.

                  DATED as of this ___ day of December, 1999.

                                       DATATEC SYSTEMS, INC., a Delaware
                                       corporation, formerly known as Glasgal
                                       Communications, Inc.


                                       By:
                                          --------------------------------------
                                          Name:
                                          Title:


                                       HH COMMUNICATIONS, INC., an Illinois
                                       corporation


                                       By:
                                          --------------------------------------
                                          Name:
                                          Title: