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                                                                   EXHIBIT 10.41

                                  GROUND LEASE

         This Ground Lease is made this 25th day of December, 1996 by and
between Richard D. Cheek, Robert D. Cheek and Daniel S. Cheek, all Trustees
under The Cheek Family Trust "D" utd March 1, 1995 (collectively, "LANDLORD")
and PairGain Technologies, Inc., a Delaware corporation ("TENANT") upon the
following terms and conditions:

                             BASIC LEASE PROVISIONS

         A.      PREMISES: Lot No. 37, Tract No. 8590, a vacant parcel
containing approximately 1.249 acres (54,406 sf) of land commonly known as
14381 Franklin Avenue, Tustin, California.

         B.      USE OF PREMISES: Parking lot to accommodate approximately 150
cars.

         C.      LEASE TERM: Eight (8) years with one option to extend the term
for a period of five (5) years ("OPTION TERM").

                 Commencement Date: January 1, 1997

                 Expiration Date: December 31, 2004

         D.      BASIC RENT.  Four Thousand Nine Hundred Dollars ($4,900.00)
per month. (Tenant shall be entitled to two (2) months free rent.  Basic Rent
shall be payable commencing March 1, 1997 as set forth in Paragraph 3 below).

         E.      RENTAL ADJUSTMENT: During the Option Term, the rent shall be
determined by applying a factor of nine percent (9%) to then fair market value
for unimproved industrial land in the Tustin/Irvine business area.  The
resulting product shall be the annual rent during the Option Term.  The monthly
rent shall be one-twelfth (1/12) of the annual rent.

         F.      SECURITY DEPOSIT: Ten Thousand Dollars ($10,000.00).

         G.      ADDRESS FOR PAYMENTS AND NOTICES.

                 If to Landlord:  Cheek Family Trust "D"
                                  14341 Franklin Avenue
                                  Tustin, California 92680
                                  Attn.:   Richard D. Cheek, Trustee

                 If to Tenant:    PairGain Technologies, Inc.
                                  14402 Franklin Avenue
                                  Tustin, California 92680-7013
                                  Attn.: Rob Price, Controller

                            GROUND LEASE PROVISIONS.

         1.      LEASED PREMISES.  For and in consideration of the rent to be
paid, covenants and conditions to be kept and performed by Tenant, Landlord
does hereby lease to Tenant, and Tenant hereby hires from Landlord, that
certain real property described in Item A of the Basic Lease Provisions (said
real property and all improvements from time to time constructed thereon being
hereinafter sometimes referred to as the "PREMISES").

         2.      TERMS.

                 (a)      PRIMARY TERM.  The Primary Term of this lease shall
be for eight (8) years, commencing January 1, 1997 and ending on December 31,
2004, subject, however, to earlier termination as provided in Paragraph 18(i)
of this Lease.





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                 (b)      OPTION TERM. Tenant shall have one (1) option to
extend the term of this Lease for an additional period of five (5) years
("OPTION TERM"), such Option Term to commence upon expiration of the Primary
Term of this Lease and, except for the adjustment in the Basic Rent described
in Section 4(b) hereinbelow, the same terms and conditions as herein set forth
shall apply to such Option Term.  If Tenant shall elect to exercise the
aforesaid option, it shall do so by giving written notice to Landlord not less
than thirty (30) days prior to expiration of the Primary Term of this Lease.

         3.      COMMENCEMENT OF RENT AND PAYMENT OF EXPENSES.  Tenant's
obligation for the payment as set forth in Paragraph 4 below shall commence on
March 1, 1997.  Tenant's obligation for the payment of expenses provided in
Paragraphs 8, 9, 10 and 11 below shall commence on January 1, 1997.

         4.      BASIC RENT AND ADJUSTMENTS.  Tenant hereby agrees to pay as
rent for the use and occupancy of the Premises during the term of this Lease,
without deduction or offset, at the time and in the manner as hereinafter
provided, the following sums:

                 (a)      BASIC RENT.  A basic monthly rent in the amount
specified in Item D of the Basic Lease Provisions, subject to adjustment as
hereinafter provided, shall be payable monthly in advance on the Commencement
Date and on the first day of each succeeding month thereafter for the entire
Lease Term.

                 (b)      BASIC RENT DURING OPTION TERM.  The Basic Rent during
the Option Term shall be determined by applying a factor to the then fair
market value for unimproved industrial land in the Tustin/Irvine business area.
The resulting product shall be the annual rent.  The monthly rent shall be
one-twelfth (1/12/) of the annual rent.  The fair market value of the Premises
shall be determined by an appraiser selected by Tenant and Landlord, which
appraiser shall determine the fair market value of the Premises if it were then
made available on the open market for the use set out in Paragraph 5 below but
excluding the value of the Tenant's improvements thereon.  However, in no event
shall the Basic Rent as so adjusted be less than the Basic Rent otherwise
payable immediately prior to such adjustment.  The appraiser employed to
determine the fair market value of the Premises must be a qualified MIA
Appraiser with at least ten (10) years experience appraising industrial land.
Such appraiser shall be appointed ninety (90) days or more prior to expiration
of the Lease Term.  Should Landlord and Tenant fail to appoint such appraiser
prior to ninety (90) days from termination of the Lease Term, then either
Landlord or Tenant shall have the right to apply to the Superior Court of
Orange County, California to appoint such appraiser to establish the fair
market value of the Premises.  Such appraiser shall determine the fair market
value of the Premises and render such finding in writing to the Landlord and
Tenant sixty (60) days prior to expiration of the Lease Term.  Such
determination shall be final.  The cost of such appraiser shall be divided
equally between Landlord and Tenant.

         5.      USE.  Tenant shall use the Premises for the operation of the
facilities described in Item B of the Basic Lease Provisions and for no other
use or purpose without the prior consent of Lessor.

         6.      CONSTRUCTION.

                 (a)      COMMENCEMENT.  Commencing as of the date hereof and
continuing until completion, Lessee shall construct a paved parking lot on the
Premises sufficient to accommodate approximately one hundred fifty (150) cars
in accordance with all applicable governmental laws, ordinances, regulations
and other requirements.  The Tenant shall be responsible for all costs
associated with the design, permitting and construction of such improvements.

                 (b)      FORCE MAJEURE. The time limits provided above for the
commencement and completion of construction shall be extended for, and
throughout such period of time as commencement and





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continuation of construction is prevented or delayed due to strikes, lockouts,
acts of government, acts of God, wars, riots, civil insurrection or abnormal
force of elements, provided in no event shall any extension of said period of
time be deemed to have occurred unless Tenant shall have given written notice
to Landlord within such period of time setting forth the facts giving rise to
each such extension.

         7.      RIGHT OF FIRST REFUSAL.  Landlord hereby grants to Tenant an
exclusive right of first refusal to acquire the Premises at any time during the
period commencing on the date of this Lease and ending on the expiration of the
term of this Lease extended by any Option Periods which have been exercised by
Tenant.  Landlord shall give Tenant thirty (30) days notice of receipt by
Landlord of a bona fide option to purchase the Premises, which offer is
acceptable to Landlord.  During such thirty-day period, Tenant shall have the
right to match such bona fide offer, in which event Tenant shall complete the
purchase under the same terms and conditions as set forth in such bona fide
offer.

         8.      TAXES.  Tenant shall be responsible for, and agrees to pay, no
later than ten (10) days prior to delinquency, any and all taxes, assessments,
levies, fees and other governmental charges of every kind and nature
(hereinafter collectively called "TAXES"), levied or assessed by any municipal,
county, state, federal or other taxing or assessing authority upon, against or
with respect to (i) the Premises, (ii) all personal property of any kind,
placed or installed upon or about the Premises, (iii) all alterations,
additions or improvements by Tenant of every kind and nature, if any, made to
the Premises, and (iv) rent or other charges payable by Tenant to Landlord but
expressly excluding any general net income, franchise, inheritance or ad
valorem taxes levied upon or payable by Landlord.  Tenant shall, not later than
the ten (10) day period described above or upon written request by Landlord if
payment is made earlier, furnish to Landlord a copy of the receipted of tax
bill or other proof of said payment.  If any such charges are not paid when
due, Landlord may pay the same, and any amount so paid by the Landlord shall
thereupon become due to Landlord from Tenant as additional rent, together with
interest thereon.

         9.      REPAIRS AND UPKEEP.

                 (a)      NO OBLIGATIONS OF LANDLORD. Landlord shall not be
required or obligated to make any changes, alterations, additions, improvements
or repairs in, on or about the Premises or any part thereof, during the Term of
this Lease.

                 (b)      TENANT OBLIGATIONS.  At all times during the term of
this Lease, Tenant shall, at its sole cost and expense, keep and maintain the
Premises and all improvements thereon and all facilities appurtenant thereto in
a first-class condition, order and repair at least equal in quality to that
maintained by other owners of such properties of similar class and condition in
Orange County, California.

         10.     UTILITY CHARGES. Tenant shall pay all charges for gas, water,
sewer, electricity, telephone and other utility services used for the Premises
during the Lease Term, and shall indemnify Landlord and the Premises from and
against any such charges or liens arising therefrom.

         11.     INSURANCE.

                 (a)     POLICY FORM AND EVIDENCE OF COVERAGE.  All policies of
insurance provided for herein shall be written as primary policies (without
"contribution") with responsible and solvent insurance companies authorized to
do business in California.  Prior to the commencement of construction described
in Section 6 above, Tenant shall supply Landlord a true and correct copy of all
such policies or Certificates of Insurance actually reflecting the coverage
required hereby, together with satisfactory evidence showing that all the
premiums thereon have been paid, and thereafter as additional





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premiums become due, Tenant shall supply Landlord with satisfactory evidence
that all such premiums have been paid.  Notwithstanding anything to the
contrary contained in this provision, Tenant's obligations to carry insurance
as provided herein may be brought within the coverage of a so-called "blanket"
policy or policies of insurance carried and maintained by Tenant, so long as
such policy or policies segregate the amount of coverage applicable to the
Premises.

         (b)     TYPES AND LIMITS OF COVERAGE. Tenant, at its sole cost and
expense, shall during the entire term hereof, procure, pay for and keep in full
force and effect comprehensive general liability and property damage insurance
with respect to the Premises and the operations of, or on behalf of Tenant in,
on or about the Premises, including, but not limited to owned and non-owned
automobile (vehicle) liability, personal injury, on or at the Premises for not
less than One Million Dollars ($1,000,000) combined limit per occurrence for
bodily injury, death and property damage liability.

         12.     DAMAGE AND DESTRUCTION.

                 (a)      TENANT'S OBLIGATIONS.  If any improvement erected by
Tenant on the Premises or any part thereof, shall be damaged or destroyed, by
any casualty during the term of this Lease, Tenant shall, at its own cost and
expense, repair or restore the same according to the original plans thereof or
according to such modified plans as shall previously be approved by a writing
by Landlord.

                 (b)      TENANT'S OPTION TO TERMINATE.  Notwithstanding
anything to the contrary contained in the preceding paragraph, if during the
last two years of the Term or the Option Term any improvements shall be damaged
by any casualty and the cost of repairing or restoring the same shall exceed
the insurance proceeds payable for such damage, then Tenant shall have the
option to be exercised within thirty (30) days after such event to repair or
restore said improvement or terminate this Lease by written notice thereof to
Landlord.  Notwithstanding the above, the option to terminate under this
paragraph may only be exercised if the Easement and Catellus Lease (as those
terms are defined in Paragraph 16(b) below are also terminated).

         13.     LIENS AND CLAIMS.  Tenant shall not suffer or permit to be
enforced against the Premises or any part thereof, or any of the improvements
thereon, any mechanics', materialmens', contractors' or subcontractors' liens
arising from any claim for damage growing out of the work of any construction,
repair, restoration, replacement or improvement, or any other claim or damage
howsoever the same may arise, but Tenant shall pay or cause to be paid all of
such liens, claims or demands before any action is brought to enforce the same
against said Premises.  Notwithstanding the foregoing, if Tenant shall in its
good faith contest the validity of any such lien, then Tenant shall, at its
sole cost and expense, defend itself and Landlord against the same and shall
pay and satisfy any adverse expense or cost or any adverse judgment that may be
rendered thereon before the enforcement thereof against Landlord or the
Premises, upon the condition that if Landlord shall require, Tenant shall
furnish to Landlord a surety bond satisfactory to Landlord in an amount at
least equal to such contested lien indemnifying Landlord against liability for
the same, and holding the Premises free from the effect of such lien or if
Landlord shall request, Tenant shall procure and record the bond provided for
in the California Civil Code, or any comparable statute hereinafter enacted
providing for the bond freeing the Premises from the effect of such lien.

         14.     ASSIGNMENT AND SUBLETTING.  Neither the Tenant nor any
trustee, receiver or other successor to Tenant shall, either voluntarily or by
operation of law, assign, sell, encumber, pledge or otherwise transfer all or
any part of Tenant's leasehold estate hereunder, or permit the Premises to be
occupied by anyone other than Tenant or Tenant's employees or sublet the
Premises or any portion thereof without Landlord's prior written consent in
each instance, which consent shall not be unreasonably withheld.





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         15.     DEFAULTS AND REMEDIES.

                 (a)      DEFAULTS.  The occurrence of any one or more of the
following events shall constitute a default by Tenant: (i) abandonment of the
Premises; (ii) failure by Tenant to make any payment of rent or other payment
or charge required to be made by Tenant hereunder as and when due, where such
failure shall continue for a period of ten (10) days after written notice
thereof from Landlord to Tenant; or (iii) failure by Tenant to perform any
other express or implied covenants or provisions herein contained and should
such failure continue for thirty (30) days after written notice thereof from
Landlord to Tenant specifying the particulars of such default, provided,
further, that if the nature of Tenant's default is such that more than thirty
(30) days are reasonably required for its cure, then Tenant shall not be deemed
to be in default if Tenant shall commence such cure within said thirty (30) day
period and thereafter diligently prosecute such cure to completion.

                 (b)      REMEDIES. If any of such events of default shall
occur, in addition to any or all other rights or remedies of the Landlord
hereby or by law provided, Landlord may terminate Tenant's rights to possession
of the Premises by any lawful means, in which case this Lease shall terminate
and Tenant shall immediately surrender possession of the Premises to Landlord.
In such event, Landlord shall be entitled to recover from Tenant damages as set
forth in Section 1951.2 of the California Civil Code.

         16.     SURRENDER, REMOVAL AND TITLE TO IMPROVEMENTS.

                 (a)      STATUS OF IMPROVEMENTS.  Upon expiration or other
termination of this Lease, Landlord may require Tenant, at its expense, to
promptly and diligently remove, demolish and/or clear off from the Premises all
or any designated portion of the improvements and other property of whatsoever
nature placed or owned by Tenant or its successor-in-interest thereon, whether
or not affixed to the Premises or to any improvements thereon, and after such
removal or clearance, Tenant shall restore the surface of the ground to a grade
properly filled, level and in uniform condition, free from all excavations and
debris.  Rent, as provided in Paragraph 4 above, shall continue until the
removal and restoration is completed.

                 (b)      TERMINATION OF EASEMENT.  Landlord and Tenant hereby
acknowledge that a Grant of Easement for Parking, Use and Maintenance
("EASEMENT") dated of even date herewith has been executed by Landlord and
Catellus Development Corporation, a Delaware corporation, ("CATELLUS") at the
request of Tenant herein.  Further, Landlord and Tenant hereby acknowledge that
Tenant has executed that certain lease of even date herewith with Catellus
describing certain real property commonly referred to as 14352 Franklin Avenue,
Tustin, California ("CATELLUS LEASE").  Tenant and Landlord hereby agree that
the Easement shall be terminated concurrently with expiration or earlier
termination of this Ground Lease and the Catellus Lease.  Any failure by Tenant
to cause the termination of the Easement in the manner set forth above shall be
deemed a material default under this Ground Lease and Tenant shall be liable
for direct damages caused by such default suffered by Landlord.

         17.     CONDEMNATION.

                 (a)      TOTAL TAKING.  If during the term hereof there shall
be a total taking by a public authority under the power of eminent domain, then
the leasehold estate of Tenant in and to the Premises shall cease and terminate
as of the date of actual and physical possession thereof shall be taken.

                 (b)      PARTIAL TAKING.  If during said term there shall be a
partial taking of the Premises, this Lease shall terminate as to the portion of
the Premises taken on the date when actual possession is taken pursuant to said
eminent domain proceedings, but said Lease shall continue in full force and
effect as to the remainder of said





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Premises.  The Basic Rent payable by Tenant for the balance of said term shall
be abated in the ratio that the square footage of the ground area of the
Premises taken bears to the total ground area of said Premises at the time of
such taking.  In the event of such taking, Tenant may, in its sole and absolute
discretion, terminate this Lease as of the date of such partial taking.

                 (c)      ALLOCATION OF AWARD. All compensation and damages
awarded for the taking of the Premises or any portion thereof shall be
apportioned between Landlord and Tenant in the manner set forth in California
law or as provided by the condemning authority.

         18.     MISCELLANEOUS PROVISIONS.

                 (a)      NOTICES.  Any notice, election, demand or other
communication to be given by either party to the other hereunder may be
delivered in person to an authorized representative of the other party, or may
be deposited in the United States mail, duly registered or certified, with
postage prepaid, return receipt requested and addressed to the party for whom
intended as follows:

                 If to Landlord:  at the address set forth in the Basic
                                  Lease Provisions of this Lease.

                 If to Tenant:    at the address set forth in the Basic
                                  Lease Provisions of this Lease.

Either of the parties hereto may hereafter respectively designate another
address as provided above.  Service of any such written notice shall be deemed
complete at the time of such personal delivery or within two (2) days after the
mailing thereof as hereinabove provided.

                 (b)      ENTIRE AGREEMENT.  This Lease covers in full each and
every agreement of every kind and nature whatsoever between the parties hereto
concerning the Premises, and all preliminary negotiations and agreements of
whatsoever kind with respect to the Premises, except those contained herein,
are superseded and of no further force or effect.

                 (c)      AMENDMENT TO LEASE.  No amendment or other
ratification of this Lease shall be effective unless in a writing signed by
Tenant and Landlord.

                 (d)      CONTROLLING LAW.  This Lease shall be governed by and
construed in accordance with the laws of the State of California.

                 (e)      TIME IS OF THE ESSENCE.  Time is of the essence of
each provision of this instrument of which time is an element.

                 (f)      SEVERABILITY OF PROVISIONS.  If any term, covenant or
condition of this Lease or the application thereof to any entity or
circumstance shall be invalid or unenforceable, the remainder of this Lease
shall not be affected thereby.

                 (g)      ATTORNEYS' FEES.  In the event any action is brought
by Landlord or Tenant against the other to enforce the breach of any of the
terms, covenants or conditions contained in this Lease, the prevailing party
shall be entitled to recover reasonable attorneys' fees to be fixed by the
court, together with costs of the suit therein incurred.

                 (h)      SUCCESSORS AND ASSIGNS.  This Lease shall inure to
the benefit of and be binding upon Landlord and Tenant and their respective
heirs, executors, legal representatives, successors and assigns.

                 (i)      CONTINGENCY. The enforceability of this Lease
Agreement between Landlord and Tenant is specifically conditioned upon the
following conditions precedent, which shall be deemed satisfied by Tenant in
its sole, absolute and unfettered discretion:





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                          1.      Physical inspection of the property,
including inspection of the soils and environmental condition of the Premises.

                          2.      The issuance by the City of Tustin of a
conditional use permit for use of the Premises as a parking lot and use of that
certain real property located at 14352 Franklin Avenue, Tustin, California by
Tenant which permitted use shall be subject to the prior review and approval by
Tenant in its sole, unfettered and absolute discretion.

                          3.      The successful execution of the Lease for the
property located at 14352 Franklin Avenue, Tustin, California.

                          4.      Approval of this Lease by the Board of
Directors of Tenant.

                          5.      The execution by all necessary parties of
that certain agreement entitled "Limited Secondary Agreement to Remove
Improvements" by and between Landlord and Catellus Development Corporation.

These conditions precedent shall be deemed satisfied upon receipt of written
notice of such satisfaction delivered to Landlord by Tenant.  If these
conditions are not satisfied, Tenant may elect to cancel this Lease upon
written notice to Landlord at any time thereafter.

                 (j)      SECURITY DEPOSIT. Upon the mutual execution of this
Lease, Tenant shall deposit with Landlord the Security Deposit (as defined in
the Basic Lease Provisions) and shall make an additional deposit of the first
month's rent ("FIRST MONTH'S RENT").  Such Security Deposit shall act as the
last month's rent under this Lease and shall insure the due, full and complete
performance by Tenant of all of the terms, covenants and conditions contained
in this Lease.  The Security Deposit shall be applied to the last month's rent
and therefore Tenant shall not be required to make the last monthly rent
payment under this Lease.  The First Month's Rent shall apply to the Basic Rent
for the first month of the Lease Term.

                 (k)      COOPERATION. Tenant shall obtain from the City of
Tustin a conditional use permit to utilize the Premises as a parking lot.
Landlord shall cooperate with Tenant, render all reasonable assistance to
Tenant, and execute any documents reasonably requested by Tenant in order for
Tenant to obtain such conditional use permit.

                 IN WITNESS WHEREOF, the parties hereto have executed this
Lease as of the date and year first above written.

                                        "LANDLORD"

                                        /s/ RICHARD D. CHEEK, TRUSTEE
                                        ----------------------------
                                        Richard D. Cheek, Trustee under
                                        The Cheek Family Trust "D" utd
                                        March 1, 1995


                                        /s/ ROBERT D. CHEEK, TRUSTEE
                                        ---------------------------
                                        Robert D. Cheek, Trustee under
                                        The Cheek Family Trust "D" utd
                                        March 1, 1995


                                        /s/ DANIEL S. CHEEK, TRUSTEE
                                        ----------------------------
                                        Daniel S. Cheek, Trustee under
                                        The Cheek Family Trust "D" utd
                                        March 1, 1995



                                        "TENANT"

                                        PairGain Technologies, Inc.,
                                        a Delaware corporation


                                        By: /s/ CHARLES W. MCBRAYER
                                            -----------------------
                                            Name: Charles W. McBrayer
                                            Its: Chief Financial Officer


                                        
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               LIMITED SECONDARY AGREEMENT TO REMOVE IMPROVEMENTS

        THIS AGREEMENT is made as of the 31st day of December 1996 ("Effective
Date") by and between CATELLUS DEVELOPMENT CORPORATION, a Delaware corporation
("Catellus") and RICHARD CHEEK, ROBERT D. CHEEK, AND DANIEL S. CHEEK, all
Trustees of THE CHEEK FAMILY TRUST "D" UDT March 1, 1995 (the "Cheek Trust").

                                    RECITALS

        A.      Catellus is the owner of that certain real property commonly
known 14352 Franklin Ave., Tustin, California, as more particularly described
on Exhibit A attached hereto and made a part hereof by this reference (the
"Catellus Property").

        B.      The Cheek Trust is the owner of that certain real property
located in the City of Tustin, California, as more particularly described on
attached hereto and made a part hereof by this reference (the "Cheek
Property"), which property is located near the Catellus Property.

        C.      Catellus has or intends to enter into a lease (the "Building
Lease") with PairGain Technologies, Inc., a Delaware corporation ("PairGain")
whereby PairGain intends to construct certain improvements (the "Tenant
Improvements") to the existing Building on the Catellus Property for use by
PairGain during the term of the Building Lease.  As a condition to allowing
such Tenant Improvements to be constructed, the City of Tustin has required
that PairGain obtain additional parking and has required that the parking
rights be evidenced by a Grant of Easement to be recorded on the Cheek
Property.  Accordingly, PairGain has entered into a lease (the "Ground Lease")
with the Cheek Trust for use of the Cheek Property as a parking lot.

        D.      Catellus has required as a part of the Building Lease and
related documentation, that, among other things, PairGain (a) remove the Tenant
Improvements in accordance with the provisions of the Building Lease at the
termination or expiration of the Building Lease, and (b) indemnify and hold
Catellus free and harmless from any and all costs, damages, liabilities, or
consequences, whether monetary or otherwise, resulting from the building of the
Tenant Improvements, the Conditional Use Permit from the City of 
Tustin, and the Ground Lease.

        E.      It is the intent of the parties that the Ground Lease be
terminated upon termination or expiration of the Building Lease.

        F.      The Cheek Trust desires the assurance of Catellus that in the
event PairGain defaults in its obligation to remove the improvements such that
the Ground Lease can be terminated and any encumbrance relating thereto may be
removed from the title to the Cheeks Property, and Catellus is willing to give
such assurance on the limited terms of this Agreement.

        NOW THEREFORE, the parties agree as follows:

1.      AGREEMENT TO REMOVE IMPROVEMENTS

        Catellus hereby agrees that in the event PairGain fails to remove the
Tenant Improvements and restore the Premises to the termination condition
called for in the Building Lease on or before ninety (90) days from the
expiration or termination of the Building Lease, including any extensions or
options thereof, Catellus will promptly undertake and pursue to completion the
removal of such improvements and restoration to the condition called for in the
Building Lease at its cost and expense; provided however, that such
undertaking on the part of Catellus shall in no way be deemed a waiver of its
rights to indemnity from PairGain nor of the primary responsibility of PairGain
with respect to such removal.  Further, notwithstanding the foregoing, Catellus
shall not have any obligation or responsibility with respect to removal of any
portion of the Tenant Improvements nor restoration which is not required as a
condition by the City of Tustin to consenting to and permitting the termination
of the Ground Lease and the removal of the encumbrance related to the grant of
an easement for parking in connection therewith.

2.      AGREEMENT FOR SOLE BENEFIT OF THE CHEEK TRUST.

 
<PAGE>   9
        This Agreement is intended for and strictly limited to the Cheek Trust
and its successors-in-interest to the Cheek Property.  Nothing in this
agreement shall be construed as granting any other party, including but not
limited to PairGain and the City of Tustin, any right to enforce or benefit
from this agreement.

3.      SECONDARY, NOT PRIMARY OBLIGATION.

        The agreement of Catellus shall be deemed secondary to the obligation
of PairGain directly to The Cheek Trust, and Catellus shall not be deemed the
primary obligor for the removal of the Tenant Improvements.  The Cheek Trust
shall look first to PairGain for removal and restoration sufficient to result
in the Ground Lease termination and reconveyance of the easement encumbering
the Cheeks Property related thereto.

4.      NO REPRESENTATION OR WARRANTY.

        No representation or warranty, of any nature or kind, is made by
Catellus except for the limited agreement to remove the Tenant Improvements as
specifically set forth herein.

5.      GENERAL PROVISIONS.

        This Agreement may be executed in multiple counterparts, each of which
shall be deemed an original Agreement, and all of which shall constitute one
Agreement to be effective as of the Effective Date.  In the event any action is
brought to enforce or interpret any of the terms and provisions of this
Agreement, the "prevailing party" in such action shall be entitled to recover,
as an element of costs of suit and not as damages, reasonable costs and
expenses, including but not limited to taxable costs and reasonable attorneys'
fees.  Each of the undersigned shall have joint and several liability for each
and every obligation set forth herein.  This Agreement shall be binding upon
and inure to the benefit of the parties and their successors and assigns.  The
parties and their successors and assigns agree to execute any and all documents
reasonably advisable and/or necessary to effectuate the terms and intent of
this Agreement.  If any provision of this Agreement as applied to any party or
circumstance shall be adjudged by a court to be void and unenforceable, the
same shall in no way affect any other provision of this Agreement or the
validity and enforceability of the Agreement as a whole.  This Agreement shall
be governed by the laws of the State of California.

        "Catellus"              CATELLUS DEVELOPMENT CORPORATION
                                a Delaware corporation

                                By      /s/ ANA MARIA PEREZ
                                  ------------------------------------------
                                  Its   Vice President
                                     ---------------------------------------

        "The Cheeks Trust"      THE CHEEK FAMILY TRUST "D" UDT MARCH 1, 1995

                                By      /s/ RICHARD D. CHEEK, TRUSTEE
                                  ------------------------------------------
                                        Richard D. Cheek, Trustee

                                By      /s/ ROBERT D. CHEEK, TRUSTEE
                                  ------------------------------------------
                                        Robert D. Cheek, Trustee

                                By      /s/ DANIEL S. CHEEK, TRUSTEE
                                  ------------------------------------------
                                        Daniel S. Cheek, Trustee

READ, APPROVED, and AGREED TO:

PAIRGAIN TECHNOLOGIES, INC.,
a Delaware corporation

By  /s/ CHARLES W. McBRAYER
  -----------------------------
  Its   CFO
      -------------------------



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