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                                                     Exhibit 10.1
[LOGO]


                        LOAN AND SECURITY AGREEMENT
BORROWERS:  SA TELECOMMUNICATIONS, INC. ("STEL")  
               U.S. COMMUNICATIONS, INC. ("USCI")
               LONG DISTANCE NETWORK, INC. ("LONG DISTANCE")
               SOUTHWEST LONG DISTANCE NETWORK, INC. ("SOUTHWEST")

ADDRESS:       1600 PROMENADE CENTER, 15TH FLOOR
               RICHARDSON, TEXAS  75080

DATE:       DECEMBER 26, 1996

This Loan and Security Agreement is entered into on the above date between
GREYROCK BUSINESS CREDIT, a Division of NationsCredit Commercial Corporation
("GBC"), whose address is 10880 Wilshire Boulevard, Suite 950, Los Angeles, CA 
90024 and the borrowers named above (jointly and severally, the "Borrower"),
whose chief executive office is located at the above address ("Borrower's
Address").  The Schedule to this Agreement (the "Schedule") being signed
concurrently is an integral part of this Agreement.  (Definitions of certain
terms used in this Agreement are set forth in Section 8 below.)

1.   LOANS.

 1.1  LOANS.  GBC will make loans to Borrower (the "Loans"), in amounts
determined by GBC in its sole discretion, up to the amounts (the "Credit Limit")
shown on the Schedule, provided no Default or Event of Default has occurred and
is continuing.  If at any time or for any reason the total of all outstanding
Loans and all other Obligations exceeds the Credit Limit, Borrower shall
immediately pay the amount of the excess to GBC, without notice or demand.

 1.2  INTEREST.  All Loans and all other monetary Obligations shall bear
interest at the rate shown on the Schedule, except where expressly set forth to
the contrary in this Agreement or in another written agreement signed by GBC and
Borrower.  Interest shall be payable monthly, on the last day of the month. 
Interest may, in GBC's discretion, be charged to Borrower's loan account, and
the same shall thereafter bear interest at the same rate as the other Loans. 

 1.3  FEES.  Borrower shall pay GBC the fee(s) shown on the Schedule, which are
in addition to all interest and other sums payable to GBC and are not
refundable.

2.  SECURITY INTEREST.

 2.1  SECURITY INTEREST.  To secure the payment and performance of all of the
Obligations when due, Borrower hereby grants to GBC a security interest in all
of Borrower's interest in the following, whether now owned or hereafter
acquired, and wherever located (collectively, the "Collateral"):  All Inventory,
Equipment, Receivables, and General Intangibles, including, without limitation,
all of Borrower's Deposit Accounts, all money, all collateral in which GBC is
granted a security interest pursuant to any other present or future agreement,
all property now or at any time in the future in GBC's possession, and all
proceeds (including proceeds of any insurance policies, proceeds of proceeds and
claims against third parties), all products of the foregoing, and all books and
records related to any of the foregoing.

3.  REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE BORROWER.

 In order to induce GBC to enter into this Agreement and to make Loans, Borrower
represents and warrants to GBC as follows, and Borrower covenants that the
following representations will continue to be true, and that Borrower will at
all times comply with all of the following covenants:

 3.1  CORPORATE EXISTENCE AND AUTHORITY.  Borrower, if a corporation, is and
will continue to be, duly organized, validly existing and in good standing under
the laws of the jurisdiction of its incorporation.  Borrower is and will
continue to be qualified and licensed to do business in all jurisdictions in
which any failure to do so would have a material adverse effect on Borrower*. 
The execution, delivery and performance by Borrower of this Agreement, and all
other documents contemplated hereby (i) have been duly and validly authorized,
(ii) are enforceable against Borrower in accordance with their terms (except as
enforcement may 


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        GREYROCK BUSINESS CREDIT                   LOAN AND SECURITY AGREEMENT

be limited by equitable principles and by bankruptcy, insolvency, 
reorganization, moratorium or similar laws relating to creditors' rights 
generally), (iii) do not violate Borrower's articles or certificate of 
incorporation, or Borrower's by-laws, or any law or any material agreement or 
instrument which is binding upon Borrower or its property, and (iv) do not 
constitute grounds for acceleration of any material indebtedness or 
obligation under any material agreement or instrument which is binding upon 
Borrower or its property*.

           *taken as a whole

 3.2  NAME; TRADE NAMES AND STYLES.  The name of Borrower set forth in the
heading to this Agreement is its correct name.  Listed on the Schedule are all
prior names of Borrower and all of Borrower's present and prior trade names*. 
Borrower shall give GBC 30 days' prior written notice before changing its name
or doing business under any other name**.  Borrower has complied, and will in
the future comply***, with all laws relating to the conduct of business under a
fictitious business name.

 *DURING THE PAST EIGHT YEARS

 **, EXCEPT THAT, IN THE CASE OF DOING BUSINESS UNDER ANOTHER NAME AS A RESULT
OF AN ACQUISITION, SUCH NOTICE SHALL BE GIVEN BEFORE OR WITHIN 20 DAYS AFTER
SUCH ACQUISITION IS CONSUMMATED

 ***IN ALL MATERIAL RESPECTS

 3.3  PLACE OF BUSINESS; LOCATION OF COLLATERAL.  The address set forth in the
heading to this Agreement is Borrower's chief executive office.  In addition, *
Borrower has places of business and Collateral is located only at the locations
set forth on the Schedule.  Borrower will give GBC at least 30 days prior
written notice before opening any additional place of business, changing its
chief executive office, or moving any of the Collateral to a location other than
Borrower's Address or one of the locations set forth on the Schedule**.

 *ON THE DATE HEREOF

 **, EXCEPT THAT (I) IN THE CASE OF OPENING ANY ADDITIONAL PLACE OF BUSINESS AS
A RESULT OF AN ACQUISITION, SUCH NOTICE SHALL BE GIVEN BEFORE OR WITHIN 20 DAYS
AFTER SUCH ACQUISITION IS CONSUMMATED, AND (II) NOTICE NEED NOT BE GIVEN OF THE
OPENING OR CHANGING OF SALES OFFICES AT WHICH NO SIGNIFICANT COLLATERAL IS
LOCATED, OR SWITCHES

 3.4  TITLE TO COLLATERAL; PERMITTED LIENS.  Borrower is now, and will at all
times in the future be, the sole owner of all the Collateral, except for items
of Equipment which are leased by Borrower.  The Collateral now is and will
remain free and clear of any and all liens, charges, security interests,
encumbrances and adverse claims, except for Permitted Liens.  GBC now has,
and will continue to have, a first-priority perfected and enforceable
security interest in all of the Collateral, subject only to the Permitted 
Liens, and Borrower will at all times defend GBC and the Collateral against 
all claims of others.  Borrower is not and will not become a lessee under any
real property lease pursuant * to which the lessor may obtain any rights in
any of the Collateral and no such lease now prohibits, restrains, impairs or
will prohibit, restrain or impair Borrower's right to remove any Collateral 
from the leased premises.  Whenever any Collateral is located upon premises
in which any third party has an interest (whether as owner, mortgagee,
beneficiary under a deed of trust, lien or otherwise)**, Borrower shall,
whenever requested by GBC, use its *** best efforts to cause such third party
to execute and deliver to GBC, in form acceptable to GBC, such waivers and
subordinations as GBC shall specify, so as to ensure that GBC's rights in the
Collateral are, and will continue to be, superior to the rights of any such 
third party**.  Borrower will keep in full force and effect, and will comply 
with all the terms of, any lease of real property where any of the Collateral
now or in the future may be located.

 *(OTHER THAN LEASES FOR SALES OFFICES OR SWITCHING EQUIPMENT)

 **(OTHER THAN A PERMITTED LIEN)

 ***COMMERCIALLY REASONABLE

 3.5  MAINTENANCE OF COLLATERAL.  Borrower will maintain the Collateral in good
working condition, ordinary wear and tear excepted *, and Borrower will not use
the Collateral for any unlawful purpose.  Borrower will immediately advise GBC
in writing of any material loss or damage to the Collateral.

 *(PROVIDED THAT NOTHING HEREIN SHALL PREVENT BORROWER OR ANY OF ITS
SUBSIDIARIES FROM DISCONTINUING THE OPERATION AND MAINTENANCE OF ANY OF ITS
PROPERTIES IF THE SAME IS, IN THE JUDGMENT OF SUCH ENTITY, DESIRABLE IN THE
CONDUCT OF ITS BUSINESS AND WOULD NOT HAVE A MATERIAL ADVERSE EFFECT ON THE
FINANCIAL CONDITION OF BORROWER TAKEN AS A WHOLE)

 3.6  BOOKS AND RECORDS.  Borrower has maintained and will maintain at
Borrower's Address * complete and accurate books and records, comprising an
accounting system in accordance with generally accepted accounting principles.

 *OR AT THE ADDRESSES SET FORTH IN THE SCHEDULE

 3.7  FINANCIAL CONDITION, STATEMENTS AND REPORTS.  All financial statements now
or in the future delivered to GBC have been, and will be, prepared in conformity
with generally accepted accounting principles * and now and in the future will
completely and fairly reflect the financial condition of Borrower, at the times
and for the periods therein stated.  Between the last date covered by any such
statement provided to GBC and the date hereof, there has been no material
adverse change in the financial condition or business of Borrower**.  Borrower
is now and will continue to be solvent.

 *(EXCEPT THAT ONLY ANNUAL FINANCIAL STATEMENTS WILL CONTAIN FOOTNOTES)


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        GREYROCK BUSINESS CREDIT                   LOAN AND SECURITY AGREEMENT

 **TAKEN AS A WHOLE

 3.8  TAX RETURNS AND PAYMENTS; PENSION CONTRIBUTIONS.  Borrower has timely
filed, and will timely file, all tax returns and reports required by applicable
law, and Borrower has timely paid, and will timely pay, all applicable taxes,
assessments, deposits and contributions now or in the future owed by Borrower. 
Borrower may, however, defer payment of any contested taxes, provided that
Borrower (i) in good faith contests Borrower's obligation to pay the taxes by
appropriate proceedings promptly and diligently instituted and conducted, (ii)
notifies GBC in writing of the commencement of, and any material development in,
the proceedings, and (iii) posts bonds or takes any other steps required to keep
the contested taxes from becoming a lien upon any of the Collateral.  Borrower
is unaware of any claims or adjustments proposed for any of Borrower's prior tax
years which could result in additional taxes becoming due and payable by
Borrower.  Borrower has paid, and shall continue to pay all amounts necessary to
fund all present and future pension, profit sharing and deferred compensation
plans in accordance with their terms, and Borrower has not and will not withdraw
from participation in, permit partial or complete termination of, or permit the
occurrence of any other event with respect to, any such plan which could result
in any * liability of Borrower**, including any liability to the Pension Benefit
Guaranty Corporation or any other governmental agency.

 *MATERIAL

 **TAKEN AS A WHOLE

 3.9  COMPLIANCE WITH LAW.  Borrower has complied, and will comply, in all
material respects, with all provisions of all applicable laws and regulations,
including, but not limited to, those relating to Borrower's ownership of real or
personal property, the conduct and licensing of Borrower's business, and all
environmental matters.

 3.10  LITIGATION.  Except as disclosed in the Schedule, there is no claim,
suit, litigation, proceeding or investigation pending or (to best of Borrower's
knowledge) threatened by or against or affecting Borrower in any court or before
any governmental agency (or any basis therefor known to Borrower) which may
result, either separately or in the aggregate, in any material adverse change in
the financial condition or business of Borrower*, or in any material impairment
in the ability of Borrower to carry on its business in substantially the same
manner as it is now being conducted.  Borrower will promptly inform GBC in
writing of any claim, proceeding, litigation or investigation in the future
threatened or instituted against Borrower involving any single claim of **. 

 *TAKEN AS A WHOLE

 **$200,000 OR MORE, OR INVOLVING $500,000 OR MORE IN THE AGGREGATE

 3.11  USE OF PROCEEDS.  All proceeds of all Loans shall be used solely for
lawful business purposes.  

4.  RECEIVABLES.

 4.1  REPRESENTATIONS RELATING TO RECEIVABLES.  Borrower represents and warrants
to GBC as follows:  Each Receivable with respect to which Loans are requested by
Borrower shall, on the date each Loan is requested and made, represent an
undisputed, bona fide, existing, unconditional obligation of the Account Debtor
created by the sale, delivery, and acceptance of goods or the rendition of
services, in the ordinary course of Borrower's business.

 4.2  REPRESENTATIONS RELATING TO DOCUMENTS AND LEGAL COMPLIANCE.  Borrower
represents and warrants to GBC as follows:  All statements made and all unpaid
balances appearing in all invoices, instruments and other documents evidencing
the Receivables are and shall be true and correct and all such invoices,
instruments and other documents and all of Borrower's books and records are and
shall be genuine and in all respects what they purport to be, and all
signatories and endorsers have the capacity to contract.  All sales and other
transactions underlying or giving rise to each Receivable shall comply with all
applicable laws and governmental rules and regulations.  All signatures and
indorsements on all documents, instruments, and agreements relating to all
Receivables are and shall be genuine, and all such documents, instruments and
agreements are and shall be legally enforceable in accordance with their terms*.

 *(EXCEPT AS ENFORCEMENT MAY BE LIMITED BY EQUITABLE PRINCIPLES AND BY
BANKRUPTCY, INSOLVENCY, REORGANIZATION, MORATORIUM OR SIMILAR LAWS RELATING TO
THE RIGHTS OF CREDITORS GENERALLY)

 4.3  SCHEDULES AND DOCUMENTS RELATING TO RECEIVABLES.  Borrower shall deliver
to GBC transaction reports and loan requests, schedules and assignments of all
Receivables, and schedules of collections, all on GBC's standard forms;
provided, however, that Borrower's failure to execute and deliver the same shall
not affect or limit GBC's security interest and other rights in all of
Borrower's Receivables, nor shall GBC's failure to advance or lend against a
specific Receivable affect or limit GBC's security interest and other rights
therein.  Together with each such schedule and assignment, or later if requested
by GBC, Borrower shall furnish GBC with copies (or, at GBC's request, originals)
of all contracts, orders, invoices, and other similar documents, and all
original shipping instructions, delivery receipts, bills of lading, and other
evidence of delivery, for any goods the sale or disposition of which gave rise
to such Receivables, and Borrower warrants the genuineness of all of the
foregoing.  Borrower shall also furnish to GBC an aged accounts receivable trial
balance in such form and at such intervals as GBC shall request.  In addition,
Borrower shall deliver to GBC the originals of all instruments, chattel paper,
security agreements, guarantees and other documents and property evidencing or
securing any Receivables, immediately upon receipt thereof and in the same form
as received, with all necessary indorsements.  


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        GREYROCK BUSINESS CREDIT                   LOAN AND SECURITY AGREEMENT

 4.4  COLLECTION OF RECEIVABLES.  *

 *ALL PROCEEDS OF RECEIVABLES (OTHER THAN EXCLUDED RECEIVABLES) SHALL BE
DEPOSITED BY BORROWER INTO A LOCKBOX ACCOUNT, OR SUCH OTHER "BLOCKED ACCOUNT" AS
GBC MAY REQUIRE (EACH, A "BLOCKED ACCOUNT") PURSUANT TO AN ARRANGEMENT WITH SUCH
BANK AS MAY BE SELECTED BY BORROWER AND BE ACCEPTABLE TO GBC.  BORROWER SHALL
ISSUE TO ANY SUCH BANK AN IRREVOCABLE LETTER OF INSTRUCTION DIRECTING SAID BANK
TO TRANSFER SUCH FUNDS SO DEPOSITED TO GBC, EITHER TO ANY ACCOUNT MAINTAINED BY
GBC AT SAID BANK OR BY WIRE TRANSFER TO APPROPRIATE ACCOUNT(S) OF GBC.  ALL
FUNDS DEPOSITED IN A BLOCKED ACCOUNT SHALL IMMEDIATELY BECOME THE SOLE PROPERTY
OF GBC AND SHALL BE APPLIED TO THE OBLIGATIONS IN SUCH ORDER AS GBC SHALL
DETERMINE. BORROWER SHALL OBTAIN THE AGREEMENT BY SUCH BANK TO WAIVE ANY OFFSET
RIGHTS AGAINST THE FUNDS SO DEPOSITED.  GBC ASSUMES NO RESPONSIBILITY FOR ANY
BLOCKED ACCOUNT ARRANGEMENT, INCLUDING WITHOUT LIMITATION, ANY CLAIM OF ACCORD
AND SATISFACTION OR RELEASE WITH RESPECT TO DEPOSITS ACCEPTED BY ANY BANK
THEREUNDER.  

 4.5  DISPUTES.  Borrower shall notify GBC promptly of all disputes or claims
relating to Receivables on the regular reports to GBC.  Borrower shall not
forgive, or settle any Receivable for less than payment in full, or agree to do
any of the foregoing, except that Borrower may do so, provided that: (i)
Borrower does so in good faith, in a commercially reasonable manner, in the
ordinary course of business, and in arm's length transactions, which are
reported to GBC on the regular reports provided to GBC; (ii) no Default or Event
of Default has occurred and is continuing; and (iii) taking into account all
such settlements and forgiveness, the total outstanding Loans and other
Obligations will not exceed the Credit Limit.  

 4.6  RETURNS.  Provided no Event of Default has occurred and is continuing, if
any Account Debtor returns any Inventory to Borrower in the ordinary course of
its business, Borrower shall promptly determine the reason for such return and
promptly issue a credit memorandum to the Account Debtor in the appropriate
amount (sending a copy to GBC).  In the event any attempted return occurs after
the occurrence of any Event of Default, Borrower shall (i) not accept any return
without GBC's prior written consent, (ii) hold the returned Inventory in trust
for GBC, (iii) segregate all returned Inventory from all of Borrower's other
property, (iv) conspicuously label the returned Inventory as GBC's property, and
(v) immediately notify GBC of the return of any Inventory, specifying the reason
for such return, the location and condition of the returned Inventory, and on
GBC's request deliver such returned Inventory to GBC.  

 4.7  VERIFICATION.  GBC may, from time to time, verify directly with the
respective Account Debtors the validity, amount and other matters relating to
the Receivables, by means of mail, telephone or otherwise, either in the name of
Borrower or GBC or such other name as GBC may choose, and GBC or its designee
may, at any time, notify Account Debtors that it has a security interest in the
Receivables.      

 4.8  NO LIABILITY.  GBC shall not under any circumstances be responsible or
liable for any shortage or discrepancy in, damage to, or loss or destruction of,
any goods, the sale or other disposition of which gives rise to a Receivable, or
for any error, act, omission, or delay of any kind occurring in the settlement,
failure to settle, collection or failure to collect any Receivable, or for
settling any Receivable in good faith for less than the full amount thereof, nor
shall GBC be deemed to be responsible for any of Borrower's obligations under
any contract or agreement giving rise to a Receivable.  Nothing herein shall,
however, relieve GBC from liability for its own gross negligence or willful
misconduct.

5.  ADDITIONAL DUTIES OF THE BORROWER.

 5.1  INSURANCE.  Borrower shall, at all times, insure all of the tangible
personal property Collateral and carry such other business insurance, with
insurers reasonably acceptable to GBC, in such form and amounts as GBC may
reasonably require, and Borrower shall provide evidence of such insurance to
GBC, so that GBC is satisfied that such insurance is, at all times, in full
force and effect.  All such insurance policies shall name GBC as an additional
loss payee, and shall contain a lenders loss payee endorsement in form
reasonably acceptable to GBC.  Upon receipt of the proceeds of any such
insurance, GBC shall apply such proceeds in reduction of the Obligations as
GBC shall determine in its sole discretion, except that, provided no Default
or Event of Default has occurred and is continuing, GBC shall release to
Borrower insurance proceeds with respect to Equipment *, which shall be 
utilized by Borrower for the replacement of the Equipment with respect to 
which the insurance proceeds were paid.  GBC may require reasonable assurance
that the insurance proceeds so released will be so used.  If Borrower fails to
provide or pay for any insurance, GBC may, but is not obligated to, obtain the
same at Borrower's expense.  Borrower shall promptly deliver to GBC copies of
all reports made to insurance companies.

 *NECESSARY TO CONDUCT BORROWER'S BUSINESS

 5.2  REPORTS.  Borrower, at its expense, shall provide GBC with the written
reports set forth in the Schedule, and such other written reports with respect
to Borrower (including budgets, sales projections, operating plans and other
financial documentation), as GBC shall from time to time reasonably specify.

 5.3  ACCESS TO COLLATERAL, BOOKS AND RECORDS.  At reasonable times, and on one
business day's notice, GBC, or its agents, shall have the right to inspect the
Collateral, and the right to audit and copy Borrower's books and records.  GBC
shall take reasonable steps to keep confidential all information obtained in any
such inspection or audit, but GBC shall have the right to disclose any such
information to its auditors, regulatory agencies, and attorneys, and pursuant 


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        GREYROCK BUSINESS CREDIT                   LOAN AND SECURITY AGREEMENT

to any subpoena or other legal process.  The foregoing inspections and audits 
shall be at Borrower's expense and the charge therefor shall be $600 per 
person per day (or such higher amount as shall represent GBC's then current 
standard charge for the same), plus reasonable out-of-pockets expenses.  
Borrower shall not be charged more than $5,000 per audit (plus reasonable 
out-of-pockets expenses), nor shall audits be done more frequently than four 
times per calendar year, provided that the foregoing limits shall not apply 
after the occurrence of a Default or Event of Default, nor shall they 
restrict GBC's right to conduct audits at its own expense (whether or not a 
Default or Event of Default has occurred).  Borrower will not enter into any 
agreement with any accounting firm, service bureau or third party to store 
Borrower's books or records at any location other than Borrower's Address*, 
without first obtaining GBC's written consent, which may be conditioned upon 
such accounting firm, service bureau or other third party agreeing to give 
GBC the same rights with respect to access to books and records and related 
rights as GBC has under this Agreement. 

 *OR ANY OTHER ADDRESS SET FORTH ON THE SCHEDULE   

 5.4  REMITTANCE OF PROCEEDS.  * All proceeds arising from the sale or other
disposition of any Collateral ** shall be delivered, in kind, by Borrower to 
GBC in the original form in which received by Borrower not later than the
following business day after receipt by Borrower, to be applied to the
Obligations in such order as GBC shall determine; provided that, if no 
Default or Event of Default has occurred and is continuing, and if no term 
loan is outstanding hereunder, then Borrower shall not be obligated to remit
to GBC the proceeds of the sale of Equipment which is sold in the ordinary 
course of business, in a good-faith arm's length transaction.  Borrower shall
not commingle proceeds of Collateral *** with any of Borrower's other funds or
property, and shall hold such proceeds separate and apart from such other 
funds and property and in an express trust for GBC.  Nothing in this Section
limits the restrictions on disposition of Collateral set forth elsewhere in 
this Agreement.

 *SUBJECT TO SECTION 4.4, 

 **(OTHER THAN EXCLUDED RECEIVABLES AND OTHER THAN A SALE WHICH IS PERMITTED BY
SECTION 7 OF THE SCHEDULE AND MADE AT A TIME WHEN NO DEFAULT OR EVENT OF DEFAULT
HAS OCCURRED AND IS CONTINUING)

 ***WHICH BORROWER IS REQUIRED TO REMIT TO GBC

 5.5  NEGATIVE COVENANTS.  Except as *, Borrower shall not, without GBC's prior
written consent, do any of the following:  (i) merge or consolidate with another
corporation or entity; (ii) acquire any assets, except in the ordinary course of
business; (iii) enter into any other transaction outside the ordinary course of
business; (iv) sell or transfer any Collateral, except that, provided no Default
or Event of Default has occurred and is continuing, Borrower may (a) sell ** in
the ordinary course of Borrower's business; (v) store any Inventory or other
Collateral with any warehouseman or other third party; (vi) sell any Inventory
on a sale-or-return, guaranteed sale, consignment, or other contingent basis;
(vii) make any loans of any money or other assets; (viii) incur any debts,
outside the ordinary course of business, and which would have a material,
adverse effect on Borrower *** or on the prospect of repayment of the
Obligations; (ix) guarantee or otherwise become liable with respect to the
obligations of another party or entity; (x) pay or declare any dividends on
Borrower's stock (except for dividends payable solely in stock of Borrower);
(xi) redeem, retire, purchase or otherwise acquire, directly or indirectly, any
of Borrower's stock; (xii) make any change in Borrower's capital structure which
would have a material adverse effect on Borrower *** or on the prospect of
repayment of the Obligations; or (xiii) dissolve or elect to dissolve****; or
(xiv) agree to do any of the foregoing. *****

 *PROVIDED IN SECTION 7 OF THE SCHEDULE

 **COLLATERAL (OTHER THAN RECEIVABLES AND GENERAL INTANGIBLES)  

 ***TAKEN AS A WHOLE 

 ****(EXCEPT THAT CIS AND BALTIC AND DIRECT OR INDIRECT SUBSIDIARIES OF LONG
DISTANCE AND USCI MAY BE VOLUNTARILY DISSOLVED WITH 20 DAYS PRIOR WRITTEN NOTICE
TO GBC)

 *****GBC SHALL EXECUTE AND DELIVER UCC-2 RELEASES WITH RESPECT TO SALES
PERMITTED UNDER CLAUSE 5.5(iv)(a) ABOVE ON WRITTEN REQUEST BY THE BORROWER.

 5.6  LITIGATION COOPERATION.  Should any third-party suit or proceeding be
instituted by or against GBC with respect to any Collateral or in any manner
relating to Borrower, Borrower shall, without expense to GBC, make available
Borrower and its officers, employees and agents, and Borrower's books and
records, without charge, to the extent that GBC may deem them reasonably
necessary in order to prosecute or defend any such suit or proceeding.

 5.7 NOTIFICATION OF CHANGES.  Borrower will promptly notify GBC in writing of
any change in its * officers or directors, the opening of any new bank account
or other deposit account, and any material adverse change in the business or
financial affairs of Borrower**.

 *EXECUTIVE

 **TAKEN AS A WHOLE

 5.8  FURTHER ASSURANCES.  Borrower agrees, at its expense, on request by GBC,
to execute all documents and take all actions, as GBC may deem reasonably
necessary or useful in order to perfect and maintain GBC's perfected security
interest in the Collateral, and in order to fully consummate the transactions
contemplated by this Agreement.

5.9  INDEMNITY.  BORROWER HEREBY AGREES TO INDEMNIFY GBC AND HOLD GBC HARMLESS
FROM AND AGAINST ANY AND ALL CLAIMS, DEBTS, LIABILITIES, DEMANDS, OBLIGATIONS,


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        GREYROCK BUSINESS CREDIT                   LOAN AND SECURITY AGREEMENT

ACTIONS, CAUSES OF ACTION, PENALTIES, COSTS AND EXPENSES (INCLUDING * ATTORNEYS'
FEES), OF EVERY NATURE, CHARACTER AND DESCRIPTION, WHICH GBC MAY SUSTAIN OR
INCUR BASED UPON OR ARISING OUT OF ANY OF THE OBLIGATIONS, ANY ACTUAL OR ALLEGED
FAILURE TO COLLECT AND PAY OVER ANY WITHHOLDING OR OTHER TAX RELATING TO
BORROWER OR ITS EMPLOYEES, ANY RELATIONSHIP OR AGREEMENT BETWEEN GBC AND
BORROWER, ANY ACTUAL OR ALLEGED FAILURE OF GBC TO COMPLY WITH ANY WRIT OF
ATTACHMENT OR OTHER LEGAL PROCESS RELATING TO BORROWER OR ANY OF ITS PROPERTY,
OR ANY OTHER MATTER, CAUSE OR THING WHATSOEVER OCCURRED, DONE, OMITTED OR
SUFFERED TO BE DONE BY GBC RELATING TO BORROWER OR THE OBLIGATIONS (EXCEPT ANY
SUCH AMOUNTS SUSTAINED OR INCURRED AS THE RESULT OF THE GROSS NEGLIGENCE OR
WILLFUL MISCONDUCT OF GBC OR ANY OF ITS DIRECTORS, OFFICERS, EMPLOYEES, AGENTS,
ATTORNEYS, OR ANY OTHER PERSON AFFILIATED WITH OR REPRESENTING GBC). 
NOTWITHSTANDING ANY PROVISION IN THIS AGREEMENT TO THE CONTRARY, THE INDEMNITY
AGREEMENT SET FORTH IN THIS SECTION SHALL SURVIVE ANY TERMINATION OF THIS
AGREEMENT AND SHALL FOR ALL PURPOSES CONTINUE IN FULL FORCE AND EFFECT. 

 *REASONABLE

6.   TERM.

 6.1  MATURITY DATE.  This Agreement shall continue in effect until the maturity
date set forth on the Schedule (the "Maturity Date"); provided that the Maturity
Date shall automatically be extended, and this Agreement shall automatically and
continuously renew, for successive additional terms of one year each, unless one
party gives written notice to the other, not less than sixty days prior to the
next Maturity Date, that such party elects to terminate this Agreement effective
on the next Maturity Date.

 6.2  EARLY TERMINATION.  This Agreement may be terminated prior to the Maturity
Date as follows:  (i) by Borrower, effective three business days after written
notice of termination is given to GBC; or (ii) by GBC at any time after the
occurrence of an Event of Default*, without notice, effective immediately.  If
this Agreement is terminated by Borrower or by GBC under this Section 6.2,
Borrower shall pay to GBC a termination fee (the "Termination Fee") in the
amount shown on the Schedule.  The Termination Fee shall be due and payable on
the effective date of termination and thereafter shall bear interest at a rate
equal to the highest rate applicable to any of the Obligations.

 *(WHICH HAS NOT BEEN WAIVED IN WRITING BY GBC)

 6.3  PAYMENT OF OBLIGATIONS.  On the Maturity Date or on any earlier effective
date of termination, Borrower shall pay and perform in full all Obligations,
whether evidenced by installment notes or otherwise, and whether or not all or
any part of such Obligations are otherwise then due and payable.  Without
limiting the generality of the foregoing, if on the Maturity Date, or on any
earlier effective date of termination, there are any outstanding letters of
credit issued based upon an application, guarantee, indemnity or similar
agreement on the part of GBC, then on such date Borrower shall provide to GBC
cash collateral in an amount equal to 110% of the face amount of all such
letters of credit plus all interest, fees and costs due or (in GBC's estimation)
likely to become due in connection therewith, to secure all of the Obligations
relating to said letters of credit, pursuant to GBC's then standard form cash
pledge agreement.  Notwithstanding any termination of this Agreement, all of
GBC's security interests in all of the Collateral and all of the terms and
provisions of this Agreement shall continue in full force and effect until all
Obligations have been paid and performed in full; provided that, without
limiting the fact that Loans are subject to the discretion of GBC, GBC may, in
its sole discretion, refuse to make any further Loans after termination.  No
termination shall in any way affect or impair any right or remedy of GBC, nor
shall any such termination relieve Borrower of any Obligation to GBC, until all
of the Obligations have been paid and performed in full.  Upon payment and
performance in full of all the Obligations and termination of this Agreement,
GBC shall promptly deliver to Borrower termination statements, requests for
reconveyances and such other documents as may be reasonably required to
terminate GBC's security interests.

7.  EVENTS OF DEFAULT AND REMEDIES.

 7.1  EVENTS OF DEFAULT.  The  occurrence of any of the following events shall
constitute an "Event of Default" under this Agreement, and Borrower shall give
GBC immediate written notice thereof: (a) Any warranty, representation,
statement, report or certificate made or delivered to GBC by Borrower or any of
Borrower's officers, employees or agents, now or in the future, shall be untrue
or misleading in a material respect*; or (b) Borrower shall fail to pay when due
any Loan or any interest thereon or any other monetary Obligation; or (c) the
total Loans and other Obligations outstanding at any time shall exceed the
Credit Limit; or (d) Borrower shall fail to perform any non-monetary Obligation
which by its nature cannot be cured; or (e) Borrower shall fail to perform any
other non-monetary Obligation, which failure is not cured within 5 business days
after the date performance is due; or (f) any levy, assessment, attachment,
seizure, lien or encumbrance (other than a Permitted Lien) is made on all or any
part of the Collateral which is not cured within 10 days after the occurrence of
the same; or (g) any default or event of default occurs under any obligation
secured by a Permitted Lien, which is not cured within any applicable cure
period or waived in writing by the holder of the Permitted Lien; or (h) Borrower
breaches any material contract or obligation, which has or may reasonably be
expected to have a material adverse effect on Borrower's business or financial
condition**; or (i) dissolution***, termination of existence, insolvency or
business failure of Borrower or any Guarantor; or appointment of a receiver,


                                    -6-

<PAGE>

        GREYROCK BUSINESS CREDIT                   LOAN AND SECURITY AGREEMENT

trustee or custodian, for all or any part of the property of, assignment for the
benefit of creditors by, or the commencement of any proceeding by Borrower or
any Guarantor under any reorganization, bankruptcy, insolvency, arrangement,
readjustment of debt, dissolution or liquidation law or statute of any
jurisdiction, now or in the future in effect; or (j) the commencement of any
proceeding against Borrower or any Guarantor under any reorganization,
bankruptcy, insolvency, arrangement, readjustment of debt, dissolution or
liquidation law or statute of any jurisdiction, now or in the future in effect,
which is not cured by the dismissal thereof within 45 days after the date
commenced; or (k) revocation or termination of, or limitation or denial of
liability upon, any guaranty of the Obligations or any attempt to do any of the
foregoing; or (l) revocation or termination of, or limitation or denial of
liability upon, any pledge of any certificate of deposit, securities or other
property or asset pledged by any third party to secure any or all of the
Obligations, or any attempt to do any of the foregoing, or commencement of
proceedings by or against any such third party under any bankruptcy or
insolvency law; or (m) Borrower makes any payment on account of any indebtedness
or obligation which has been subordinated to the Obligations other than as
permitted in the applicable subordination agreement, or if any Person who has
subordinated such indebtedness or obligations terminates or in any way limits or
terminates its subordination agreement; or (n) there shall be a change in the
record or beneficial ownership of an aggregate of more than 20% of the
outstanding shares of stock of Borrower****, in one or more transactions,
compared to the ownership of outstanding shares of stock of Borrower in effect
on the date hereof, without the prior written consent of GBC; or (o) Borrower
shall generally not pay its debts as they become due, or Borrower shall conceal,
remove or transfer any part of its property, with intent to hinder, delay or
defraud its creditors, or make or suffer any transfer of any of its property
which may be fraudulent under any bankruptcy, fraudulent conveyance or similar
law; or (p) there shall be a material adverse change in Borrower's business or
financial condition**.  GBC may cease making any Loans hereunder during any of
the above cure periods, and thereafter if an Event of Default has occurred.  

 *WHEN MADE

 **TAKEN AS A WHOLE

 ***(EXCEPT AS PERMITTED BY SECTION 5.5(xiii))

 ****(OTHER THAN STEL)

 7.2  REMEDIES.  Upon the occurrence and during the continuance of any Event of
Default, and at any time thereafter, GBC, at its option, and without notice or
demand of any kind (all of which are hereby expressly waived by Borrower), may
do any one or more of the following: (a) Cease making Loans or otherwise
extending credit to Borrower under this Agreement or any other document or
agreement; (b) Accelerate and declare all or any part of the Obligations to be
immediately due, payable, and performable, notwithstanding any deferred or
installment payments allowed by any instrument evidencing or relating to any
Obligation; (c) Take possession of any or all of the Collateral wherever it may
be found, and for that purpose Borrower hereby authorizes GBC without judicial
process to enter onto any of Borrower's premises without interference to search
for, take possession of, keep, store, or remove any of the Collateral, and
remain on the premises or cause a custodian to remain on the premises in
exclusive control thereof, without charge for so long as GBC deems it reasonably
necessary in order to complete the enforcement of its rights under this
Agreement or any other agreement; provided, however, that should GBC seek to
take possession of any of the Collateral by Court process, Borrower hereby
irrevocably waives: (i) any bond and any surety or security relating thereto
required by any statute, court rule or otherwise as an incident to such
possession; (ii) any demand for possession prior to the commencement of any suit
or action to recover possession thereof; and (iii) any requirement that GBC
retain possession of, and not dispose of, any such Collateral until after trial
or final judgment; (d) Require Borrower to assemble any or all of the Collateral
and make it available to GBC at places designated by GBC which are reasonably
convenient to GBC and Borrower, and to remove the Collateral to such locations
as GBC may deem advisable; (e) Complete the processing, manufacturing or repair
of any Collateral prior to a disposition thereof and, for such purpose and for
the purpose of removal, GBC shall have the right to use Borrower's premises,
vehicles, hoists, lifts, cranes, equipment and all other property without
charge; (f) Sell, lease or otherwise dispose of any of the Collateral, in its
condition at the time GBC obtains possession of it or after further
manufacturing, processing or repair, at one or more public and/or private sales,
in lots or in bulk, for cash, exchange or other property, or on credit, and to
adjourn any such sale from time to time without notice other than oral
announcement at the time scheduled for sale.  GBC shall have the right to
conduct such disposition on Borrower's premises without charge, for such time or
times as GBC deems reasonable, or on GBC's premises, or elsewhere and the
Collateral need not be located at the place of disposition.  GBC may directly or
through any affiliated company purchase or lease any Collateral at any such
public disposition, and if permissible under applicable law, at any private
disposition.  Any sale or other disposition of Collateral shall not relieve
Borrower of any liability Borrower may have if any Collateral is defective as to
title or physical condition or otherwise at the time of sale; (g) Demand payment
of, and collect any Receivables and General Intangibles comprising Collateral
and, in connection therewith, Borrower irrevocably authorizes GBC to endorse or
sign Borrower's name on all collections, receipts, instruments and other
documents, to take possession of and open mail addressed to Borrower and remove
therefrom payments made with respect to any item of the Collateral or proceeds
thereof, and, in GBC's sole discretion, to grant extensions of time to pay,
compromise claims and settle Receivables, General Intangibles and the like for
less than face value; and (h) Demand and receive possession of any of Borrower's
federal and state income tax returns and the books and records utilized in the
preparation thereof or referring thereto.  All reasonable attorneys' fees,
expenses, costs, liabilities and obligations incurred by GBC 


                                    -7-

<PAGE>

        GREYROCK BUSINESS CREDIT                   LOAN AND SECURITY AGREEMENT

with respect to the foregoing shall be added to and become part of the 
Obligations, shall be due on demand, and shall bear interest at a rate equal 
to the highest interest rate applicable to any of the Obligations.  Without 
limiting any of GBC's rights and remedies, from and after the occurrence of 
any Event of Default, the interest rate applicable to the Obligations shall 
be increased by an additional * percent per annum.

 *THREE

 7.3  STANDARDS FOR DETERMINING COMMERCIAL REASONABLENESS.  Borrower and GBC
agree that a sale or other disposition (collectively, "sale") of any Collateral
which complies with the following standards will conclusively be deemed to be
commercially reasonable:  (i) Notice of the sale is given to Borrower at least
seven days prior to the sale, and, in the case of a public sale, notice of the
sale is published at least seven days before the sale in a newspaper of general
circulation in the county where the sale is to be conducted; (ii) Notice of the
sale describes the collateral in general, non-specific terms; (iii) The sale is
conducted at a place designated by GBC, with or without the Collateral being
present; (iv) The sale commences at any time between 8:00 a.m. and 6:00 p.m.; 
(v) Payment of the purchase price in cash or by cashier's check or wire transfer
is required; (vi) With respect to any sale of any of the Collateral, GBC may
(but is not obligated to) direct any prospective purchaser to ascertain directly
from Borrower any and all information concerning the same.  GBC shall be free to
employ other methods of noticing and selling the Collateral, in its discretion,
if they are commercially reasonable.

 7.4  POWER OF ATTORNEY.  Upon the occurrence and during the continuance of any
Event of Default, without limiting GBC's other rights and remedies, Borrower
grants to GBC an irrevocable power of attorney coupled with an interest,
authorizing and permitting GBC (acting through any of its employees, attorneys
or agents) at any time, at its option, but without obligation, with or without
notice to Borrower, and at Borrower's expense, to do any or all of the
following, in Borrower's name or otherwise, but GBC agrees to exercise the
following powers in a commercially reasonable manner:  (a) Execute on behalf of
Borrower any documents that GBC may, in its sole discretion, deem advisable in
order to perfect and maintain GBC's security interest in the Collateral, or in
order to exercise a right of Borrower or GBC, or in order to fully consummate
all the transactions contemplated under this Agreement, and all other present
and future agreements; (b) Execute on behalf of Borrower any document
exercising, transferring or assigning any option to purchase, sell or otherwise
dispose of or to lease (as lessor or lessee) any real or personal property which
is part of GBC's Collateral or in which GBC has an interest; (c) Execute on
behalf of Borrower, any invoices relating to any Receivable, any draft against
any Account Debtor and any notice to any Account Debtor, any proof of claim in
bankruptcy, any Notice of Lien, claim of mechanic's, materialman's or other
lien, or assignment or satisfaction of mechanic's, materialman's or other lien;
(d) Take control in any manner of any cash or non-cash items of payment or
proceeds of Collateral; endorse the name of Borrower upon any instruments, or
documents, evidence of payment or Collateral that may come into GBC's
possession; (e) Endorse all checks and other forms of remittances received by
GBC; (f) Pay, contest or settle any lien, charge, encumbrance, security interest
and adverse claim in or to any of the Collateral, or any judgment based thereon,
or otherwise take any action to terminate or discharge the same; (g) Grant
extensions of time to pay, compromise claims and settle Receivables and General
Intangibles for less than face value and execute all releases and other
documents in connection therewith; (h) Pay any sums required on account of
Borrower's taxes or to secure the release of any liens therefor, or both; (i)
Settle and adjust, and give releases of, any insurance claim that relates to any
of the Collateral and obtain payment therefor; (j) Instruct any third party
having custody or control of any books or records belonging to, or relating to,
Borrower to give GBC the same rights of access and other rights with respect
thereto as GBC has under this Agreement; and (k) Take any action or pay any sum
required of Borrower pursuant to this Agreement and any other present or future
agreements.  Any and all reasonable sums paid and any and all reasonable costs,
expenses, liabilities, obligations and reasonable attorneys' fees incurred by
GBC with respect to the foregoing shall be added to and become part of the
Obligations, shall be payable on demand, and shall bear interest at a rate equal
to the highest interest rate applicable to any of the Obligations.  In no event
shall GBC's rights under the foregoing power of attorney or any of GBC's other
rights under this Agreement be deemed to indicate that GBC is in control of the
business, management or properties of Borrower.

 7.5  APPLICATION OF PROCEEDS.  All proceeds realized as the result of any sale
or other disposition of the Collateral shall be applied by GBC first to the
reasonable costs, expenses, liabilities, obligations and attorneys' fees
incurred by GBC in the exercise of its rights under this Agreement, second to
the interest due upon any of the Obligations, and third to the principal of the
Obligations, in such order as GBC shall determine in its sole discretion.  Any
surplus shall be paid to Borrower or other persons legally entitled thereto;
Borrower shall remain liable to GBC for any deficiency.  If GBC, in its sole
discretion, directly or indirectly enters into a deferred payment or other
credit transaction with any purchaser at any sale of Collateral, GBC shall have
the option, exercisable at any time, in its sole discretion, of either reducing
the Obligations by the principal amount of purchase price or deferring the
reduction of the Obligations until the actual receipt by GBC of the cash
therefor.

 7.6  REMEDIES CUMULATIVE.  In addition to the rights and remedies set forth in
this Agreement, GBC shall have all the other rights and remedies accorded a
secured party under the California Uniform Commercial Code and under all other
applicable laws, and under any other instrument or agreement now or in the
future entered into between GBC and Borrower, and all of such rights and
remedies are cumulative and none is exclusive.  Exercise or partial exercise by
GBC of one or more of its rights or remedies shall not be deemed an election,
nor bar GBC from subsequent exercise or partial exercise of any other rights or


                                    -8-

<PAGE>

           GREYROCK BUSINESS CREDIT                 LOAN AND SECURITY AGREEMENT 

remedies.  The failure or delay of GBC to exercise any rights or remedies shall
not operate as a waiver thereof, but all rights and remedies shall continue in
full force and effect until all of the Obligations have been fully paid and
performed.

8.   DEFINITIONS.  As used in this Agreement, the following terms have the
following meanings:

 "ACCOUNT DEBTOR" means the obligor on a Receivable.

 "AFFILIATE" means, with respect to any Person, a relative, partner,
shareholder, director, officer, or employee of such Person, or any parent or
subsidiary of such Person, or any Person controlling, controlled by or under
common control with such Person.

 "AGREEMENT" and "THIS AGREEMENT" means this Loan and Security Agreement and all
modifications and amendments thereto, extensions thereof, and replacements
therefor.

 "BUSINESS DAY" means a day on which GBC is open for business.

 "CODE" means the Uniform Commercial Code as adopted and in effect in the State
of California  from time to time. 

 "COLLATERAL" has the meaning set forth in Section 2.1 above.

 "DEFAULT" means any event which with notice or passage of time or both, would
constitute an Event of Default.

 "DEPOSIT ACCOUNT" has the meaning set forth in Section 9105 of the Code.

  "ELIGIBLE RECEIVABLES" means unconditional Receivables arising in the ordinary
course of Borrower's business from the completed sale of goods or rendition of
services, which GBC, in its sole judgment, shall deem eligible for borrowing,
based on such considerations as GBC may from time to time deem appropriate. *

 *ELIGIBLE RECEIVABLES SHALL NOT INCLUDE EXCLUDED RECEIVABLES (AS DEFINED
BELOW).

 "EQUIPMENT" means all of Borrower's present and hereafter acquired machinery,
molds, machine tools, motors, furniture, equipment, furnishings, fixtures, trade
fixtures, motor vehicles, tools, parts, dyes, jigs, goods and other tangible
personal property (other than Inventory) of every kind and description used in
Borrower's operations or owned by Borrower and any interest in any of the
foregoing, and all attachments, accessories, accessions, replacements,
substitutions, additions or improvements to any of the foregoing, wherever
located.  *

 * "EXCLUDED RECEIVABLES" MEANS RECEIVABLES ARISING FROM TELECOMMUNICATIONS
SERVICES RENDERED TO CUSTOMERS WHICH ARE BILLED TO THE CUSTOMERS BY A REGIONAL
BELL OPERATING COMPANY, A BELL OPERATING COMPANY, A LOCAL EXCHANGE COMPANY, A
CREDIT CARD COMPANY, OR A PROVIDER OF LOCAL TELEPHONE SERVICES.

 "EVENT OF DEFAULT" means any of the events set forth in Section 7.1 of this
Agreement.

 "GENERAL INTANGIBLES" means all general intangibles of Borrower, whether now
owned or hereafter created or acquired by Borrower, including, without
limitation, all choses in action, causes of action, corporate or other business
records, Deposit Accounts, inventions, designs, drawings, blueprints, patents,
patent applications, trademarks and the goodwill of the business symbolized
thereby, names, trade names, trade secrets, goodwill, copyrights, registrations,
licenses, franchises, customer lists, security  and other deposits, rights in
all litigation presently or hereafter pending for any cause or claim (whether in
contract, tort or otherwise), and all judgments now or hereafter arising
therefrom, all claims of Borrower against GBC, rights to purchase or sell real
or personal property, rights as a licensor or licensee of any kind, royalties,
telephone numbers, proprietary information, purchase orders, and all insurance
policies and claims (including life insurance, key man insurance, credit
insurance, liability insurance, property insurance and other insurance), tax
refunds and claims, computer programs, discs, tapes and tape files, claims under
guaranties, security interests or other security held by or granted to Borrower,
all rights to indemnification and all other intangible property of every kind
and nature (other than Receivables).

 "GUARANTOR" means any Person who has guaranteed any of the Obligations.

 "INVENTORY" means all of Borrower's now owned and hereafter acquired goods,
merchandise or other personal property, wherever located, to be furnished under
any contract of service or held for sale or lease (including all raw materials,
work in process, finished goods and goods in transit), and all materials and
supplies of every kind, nature and description which are or might be used or
consumed in Borrower's business or used in connection with the manufacture,
packing, shipping, advertising, selling or finishing of such goods, merchandise
or other personal property, and all warehouse receipts, documents of title and
other documents representing any of the foregoing.



                                    -9- 
<PAGE>

           GREYROCK BUSINESS CREDIT                 LOAN AND SECURITY AGREEMENT 




 "OBLIGATIONS" means all present and future Loans, advances, debts, liabilities,
obligations, guaranties, covenants, duties and indebtedness at any time owing by
Borrower to GBC, whether evidenced by this Agreement or any note or other
instrument or document, whether arising from an extension of credit, opening of
a letter of credit, banker's acceptance, loan, guaranty, indemnification or
otherwise, whether direct or indirect (including, without limitation, those
acquired by assignment and any participation by GBC in Borrower's debts owing to
others), absolute or contingent, due or to become due, including, without
limitation, all interest, charges, expenses, fees, attorney's fees, expert
witness fees, audit fees, letter of credit fees, loan fees, termination fees,
minimum interest charges and any other sums chargeable to Borrower under this
Agreement or under any other present or future instrument or agreement between
Borrower and GBC.

 "PERMITTED LIENS" means the following:  (i) purchase money security interests
in specific items of Equipment*; (ii) leases of specific items of Equipment*;
(iii) liens for taxes not yet payable; (iv) additional security interests and
liens which are subordinate to the security interest in favor of GBC and are
consented to in writing by GBC (which consent shall not be unreasonably
withheld); (v) security interests being terminated substantially concurrently
with this Agreement; (vi) liens of materialmen, mechanics, warehousemen,
carriers, or other similar liens arising in the ordinary course of business and
securing obligations which are not delinquent; (vii) liens incurred in
connection with the extension, renewal or refinancing of the indebtedness
secured by liens of the type described above in clauses (i) or (ii) above,
provided that any extension, renewal or replacement lien is limited to the
property encumbered by the existing lien and the principal amount of the
indebtedness being extended, renewed or refinanced does not increase; (viii)
Liens in favor of customs and revenue authorities which secure payment of
customs duties in connection with the importation of goods**.  GBC will have the
right to require, as a condition to its consent under subparagraph (iv) above,
that the holder of the additional security interest or lien sign an
intercreditor agreement on GBC's then standard form, acknowledge that the
security interest is subordinate to the security interest in favor of GBC, and
agree not to take any action to enforce its subordinate security interest so
long as any Obligations remain outstanding, and that Borrower agree that any
uncured default in any obligation secured by the subordinate security interest
shall also constitute an Event of Default under this Agreement.  

 *OR SOFTWARE

 **(ix) LIENS INCURRED OR PLEDGES AND DEPOSITS MADE IN THE ORDINARY COURSE OF
BUSINESS IN CONNECTION WITH WORKER'S COMPENSATION, UNEMPLOYMENT INSURANCE AND
OTHER TYPES OF STATUTORY OBLIGATIONS (INCLUDING TO SECURE GOVERNMENT CONTRACTS)
IN THE ORDINARY COURSE OF BUSINESS, (x) ANY INTEREST OR TITLE OF A LESSOR IN
PROPERTY SUBJECT TO ANY LEASE OTHER THAN A CAPITAL LEASE, (xi) LIENS ON EXCLUDED
RECEIVABLES, (xii) SECURITY DEPOSITS MADE IN THE ORDINARY COURSE OF BUSINESS,
(xiii) PURCHASE MONEY SECURITY INTERESTS IN COLLATERAL (OTHER THAN RECEIVABLES,
INVENTORY OR GENERAL INTANGIBLES) WHICH COLLATERAL IS ACQUIRED IN AN
ACQUISITION, MERGER OR CONSOLIDATION, AND WHICH SECURES PART OF THE PURCHASE
PRICE THEREOF, PROVIDED THE HOLDER THEREOF AGREES IN WRITING TO GIVE GBC 30 DAYS
NOTICE AND OPPORTUNITY TO CURE ANY DEFAULT THEREUNDER PRIOR TO TAKING ANY
ENFORCEMENT ACTION WITH RESPECT TO THE SAME, (xiv) LIENS LISTED ON THE UCC
SEARCHES LISTED ON EXHIBIT A HERETO, (xv) THE LIEN OF THE TRUSTEE UNDER SECTION
8.07 OF THAT CERTAIN INDENTURE DATED AS OF AUGUST 12, 1996 BETWEEN STEL AND
UNITED STATES TRUST COMPANY OF NEW YORK, ON ALL MONEY OR PROPERTY HELD OF
COLLECTED BY THE TRUSTEE.

 "PERSON" means any individual, sole proprietorship, partnership, joint venture,
trust, unincorporated organization, association, corporation, government, or any
agency or political division thereof, or any other entity.

 "RECEIVABLES" means all of Borrower's now owned and hereafter acquired accounts
(whether or not earned by performance), letters of credit, contract rights,
chattel paper, instruments, securities, documents and all other forms of
obligations at any time owing to Borrower, all guaranties and other security
therefor, all merchandise returned to or repossessed by Borrower, and all rights
of stoppage in transit and all other rights or remedies of an unpaid vendor,
lienor or secured party.

 OTHER TERMS.  All accounting terms used in this Agreement, unless otherwise
indicated, shall have the meanings given to such terms in accordance with
generally accepted accounting principles, consistently applied.  All other terms
contained in this Agreement, unless otherwise indicated, shall have the meanings
provided by the Code, to the extent such terms are defined therein. 

9.   GENERAL PROVISIONS.

 9.1  INTEREST COMPUTATION.  In computing interest on the Obligations, all
checks, wire transfers and other items of payment received by GBC (including
proceeds of Receivables and payment of the Obligations in full) shall be deemed
applied by GBC on account of the Obligations on the Business Day received by GBC
in immediately available funds.  GBC shall not, however, be required to credit
Borrower's account for the amount of any item of payment which is unsatisfactory
to GBC in its discretion, and GBC may charge Borrower's Loan account for the
amount of any item of payment which is returned to GBC unpaid.  

 9.2  APPLICATION OF PAYMENTS.  All payments with respect to the Obligations may
be applied, and in GBC's sole discretion reversed and re-applied, to the
Obligations, in such order and manner as GBC shall determine in its sole
discretion.

 9.3  CHARGES TO ACCOUNT.  GBC may, in its discretion, require that Borrower pay
monetary Obligations in cash to GBC, or charge them to Borrower's Loan account,
in which event they will bear interest at the same rate applicable to the Loans.

                                    -10- 
<PAGE>

           GREYROCK BUSINESS CREDIT                 LOAN AND SECURITY AGREEMENT 


 9.4  MONTHLY ACCOUNTINGS.  GBC shall provide Borrower monthly with an account
of advances, charges, expenses and payments made pursuant to this Agreement. 
Such account shall be deemed correct, accurate and binding on Borrower and an
account stated (except for reverses and reapplications of payments made and
corrections of errors discovered by GBC), unless Borrower notifies GBC in
writing to the contrary within * days after each account is rendered,
describing the nature of any alleged errors or admissions.

 *NINETY

 9.5  NOTICES.  All notices to be given under this Agreement shall be in writing
and shall be given either personally or by reputable private delivery service or
by regular first-class mail, or certified mail return receipt requested,
addressed to GBC or Borrower at the addresses shown in the heading to this
Agreement, or at any other address designated in writing by one party to the
other party.  All notices shall be deemed to have been given upon delivery in
the case of notices personally delivered, or at the expiration of one business
day following delivery to the private delivery service, or two business days
following the deposit thereof in the United States mail, with postage prepaid. 


 9.6  SEVERABILITY.  Should any provision of this Agreement be held by any court
of competent jurisdiction to be void or unenforceable, such defect shall not
affect the remainder of this Agreement, which shall continue in full force and
effect.

 9.7  INTEGRATION.  This Agreement and such other written agreements, documents
and instruments as may be executed in connection herewith are the final, entire
and complete agreement between Borrower and GBC and supersede all prior and
contemporaneous negotiations and oral representations and agreements, all of
which are merged and integrated in this Agreement.  THERE ARE NO ORAL
UNDERSTANDINGS, REPRESENTATIONS OR AGREEMENTS BETWEEN THE PARTIES WHICH ARE NOT
SET FORTH IN THIS AGREEMENT OR IN OTHER WRITTEN AGREEMENTS SIGNED BY THE PARTIES
IN CONNECTION HEREWITH.

 9.8  WAIVERS.  The failure of GBC at any time or times to require Borrower to
strictly comply with any of the provisions of this Agreement or any other
present or future agreement between Borrower and GBC shall not waive or diminish
any right of GBC later to demand and receive strict compliance therewith.  Any
waiver of any default shall not waive or affect any other default, whether prior
or subsequent, and whether or not similar.  None of the provisions of this
Agreement or any other agreement now or in the future executed by Borrower and
delivered to GBC shall be deemed to have been waived by any act or knowledge of
GBC or its agents or employees, but only by a specific written waiver signed by
an authorized officer of GBC and delivered to Borrower.  Borrower waives demand,
protest, notice of protest and notice of default or dishonor, notice of payment
and nonpayment, release, notice of intent to accelerate, notice of acceleration,
compromise, settlement, extension or renewal of any commercial paper,
instrument, account, General Intangible, document or guaranty at any time held
by GBC on which Borrower is or may in any way be liable, and notice of any
action taken by GBC, unless expressly required by this Agreement.  

 9.9  AMENDMENT.  The terms and provisions of this Agreement may not be waived
or amended, except in a writing executed by Borrower and a duly authorized
officer of GBC.

 9.10  TIME OF ESSENCE.  Time is of the essence in the performance by Borrower
of each and every obligation under this Agreement.

 9.11  ATTORNEYS FEES AND COSTS.  Borrower shall reimburse GBC for all
reasonable attorneys' fees and all filing, recording, search, title insurance,
appraisal, audit, and other reasonable costs incurred by GBC, pursuant to, or in
connection with, or relating to this Agreement (whether or not a lawsuit is
filed), including, but not limited to, any reasonable attorneys' fees and costs
GBC incurs in order to do the following: prepare and negotiate this Agreement
and the documents relating to this Agreement; obtain legal advice in connection
with this Agreement or Borrower; enforce, or seek to enforce, any of its rights;
prosecute actions against, or defend actions by, Account Debtors; commence,
intervene in, or defend any action or proceeding; initiate any complaint to be
relieved of the automatic stay in bankruptcy; file or prosecute any probate
claim, bankruptcy claim, third-party claim, or other claim; examine, audit,
copy, and inspect any of the Collateral or any of Borrower's books and records;
protect, obtain possession of, lease, dispose of, or otherwise enforce GBC's
security interest in, the Collateral; and otherwise represent GBC in any
litigation relating to Borrower.  If either GBC or Borrower files any lawsuit
against the other predicated on a breach of this Agreement, the prevailing party
in such action shall be entitled to recover its reasonable costs and attorneys'
fees, including (but not limited to) reasonable attorneys' fees and costs
incurred in the enforcement of, execution upon or defense of any order, decree,
award or judgment.  All attorneys' fees and costs to which GBC may be entitled
pursuant to this Paragraph shall immediately become part of Borrower's
Obligations, shall be due on demand, and shall bear interest at a rate equal to
the highest interest rate applicable to any of the Obligations.

 9.12  BENEFIT OF AGREEMENT.  The provisions of this Agreement shall be binding
upon and inure to the benefit of the respective successors, assigns, heirs,
beneficiaries and representatives of Borrower and GBC; provided, however, that
Borrower may not assign or transfer any of its rights under this Agreement
without the prior written consent of GBC, and any prohibited assignment shall be
void.  No consent by GBC to any assignment shall release Borrower from its
liability for the Obligations.

 9.13  JOINT AND SEVERAL LIABILITY.  If Borrower consists of more than one
Person, their liability shall be joint and several, and the compromise of any
claim with, or the release of, any Borrower shall not constitute a compromise
with, or a release of, any other Borrower.

 9.14  LIMITATION OF ACTIONS.  Any claim or cause of action by Borrower against
GBC, its directors, officers, employees, agents, accountants or attorneys, based
upon, arising from, 

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<PAGE>

           GREYROCK BUSINESS CREDIT                 LOAN AND SECURITY AGREEMENT 


or relating to this Loan Agreement, or any other present or future document 
or agreement, or any other transaction contemplated hereby or thereby or 
relating hereto or thereto, or any other matter, cause or thing whatsoever, 
occurred, done, omitted or suffered to be done by GBC, its directors, 
officers, employees, agents, accountants or attorneys, shall be barred unless 
asserted by Borrower by the commencement of an action or proceeding in a 
court of competent jurisdiction by the filing of a complaint within one year 
after the first act, occurrence or omission upon which such claim or cause of 
action, or any part thereof, is based, and the service of a summons and 
complaint on an officer of GBC, or on any other person authorized to accept 
service on behalf of GBC, within thirty (30) days thereafter.  Borrower 
agrees that such one-year period is a reasonable and sufficient time for 
Borrower to investigate and act upon any such claim or cause of action.  The 
one-year period provided herein shall not be waived, tolled, or extended 
except by the written consent of GBC in its sole discretion.  This provision 
shall survive any termination of this Loan Agreement or any other present or 
future agreement.

 9.15  PARAGRAPH HEADINGS; CONSTRUCTION.  Paragraph headings are only used in
this Agreement for convenience.  Borrower and GBC acknowledge that the headings
may not describe completely the subject matter of the applicable paragraph, and
the headings shall not be used in any manner to construe, limit, define or
interpret any term or provision of this Agreement.  The term "including",
whenever used in this Agreement, shall mean "including (but not limited to)". 
This Agreement has been fully reviewed and negotiated between the parties and no
uncertainty or ambiguity in any term or provision of this Agreement shall be
construed strictly against GBC or Borrower under any rule of construction or
otherwise. *

 *THIS AGREEMENT MAY BE EXECUTED IN SEPARATE COUNTERPARTS, WHICH TOGETHER SHALL
CONSTITUTE ONE AGREEMENT.

 9.16  GOVERNING LAW; JURISDICTION; VENUE.  This Agreement and all acts and
transactions hereunder and all rights and obligations of GBC and Borrower shall
be governed by the laws of the State of California.  As a material part of the
consideration to GBC to enter into this Agreement, Borrower (i) agrees that all
actions and proceedings relating directly or indirectly to this Agreement shall,
at GBC's option, be litigated in courts located within California, and that the
exclusive venue therefor shall be Los Angeles County; (ii) consents to the
jurisdiction and venue of any such court and consents to service of process in
any such action or proceeding by personal delivery or any other method permitted
by law; and (iii) waives any and all rights Borrower may have to object to the
jurisdiction of any such court, or to transfer or change the venue of any such
action or proceeding.

 9.17  MUTUAL WAIVER OF JURY TRIAL.  BORROWER AND GBC EACH HEREBY WAIVE THE
RIGHT TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING BASED UPON, ARISING OUT OF,
OR IN ANY WAY RELATING TO, THIS AGREEMENT OR ANY OTHER PRESENT OR FUTURE
INSTRUMENT OR AGREEMENT BETWEEN GBC AND BORROWER, OR ANY CONDUCT, ACTS OR
OMISSIONS OF GBC OR BORROWER OR ANY OF THEIR DIRECTORS, OFFICERS, EMPLOYEES,
AGENTS, ATTORNEYS OR ANY OTHER PERSONS AFFILIATED WITH GBC OR BORROWER, IN ALL
OF THE FOREGOING CASES, WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

 Borrower:

     SA TELECOMMUNICATIONS, INC. 
     
     
     By /s/ J. David Darnell
       ------------------------------- 
          Vice President-Finance
     
     U.S. COMMUNICATIONS, INC.
     
     
     By /s/ J. David Darnell
       ------------------------------- 
          Vice President
     
     LONG DISTANCE NETWORK, INC.
     
     
     By /s/ J. David Darnell
       ------------------------------- 
         Vice President
     
     SOUTHWEST LONG DISTANCE NETWORK, INC.
     
     By /s/ J. David Darnell
       ------------------------------- 
         Vice President
     
 GBC:

     GREYROCK BUSINESS CREDIT, 
     a Division of NationsCredit Commercial Corporation
     
     
     By /s/ Ian Schneider
       ------------------------------- 
     Title  Chief Operating Officer
          ---------------------------- 



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