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                                                             English Translation

                                                                    EXHIBIT 4(u)

                  DARK FIBER OPTIC PURCHASE AND SALE AGREEMENT

                           ENTERED INTO BY AND BETWEEN

                     MAXCOM TELECOMUNICACIONES, S.A. DE C.V.

                                       AND

                              BESTEL, S.A. DE C.V.

                                AUGUST 13TH, 2002

CERTAIN MATERIAL HAS BEEN OMITTED PURSUANT TO A REQUEST FOR CONFIDENTIAL
TREATMENT. THE PLACES IN THIS DOCUMENT WHERE MATERIAL HAS BEEN OMITTED IS MARKED
WITH AN ASTERISK AND BRACKETS: "[*]." THE OMITTED MATERIAL HAS BEEN FILED
SEPARATELY WITH THE U.S. SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE
24b-2 UNDER THE SECURITIES EXCHANGE ACT OF 1934.

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                                                             English Translation

DARK FIBER OPTIC PURCHASE AND SALE AGREEMENT

THIS DARK FIBER OPTIC PURCHASE AND SALE AGREEMENT (the "Agreement") is entered
today August 13th, 2002 into by and between MAXCOM TELECOMUNICACIONES S.A. DE
C.V. ("Maxcom") represented hereof by its President and Chief Executive Officer,
Mr. Fulvio V. Del Valle, as well as its legal representative, Mr. Gonzalo
Alarcon Iturbide, and BESTEL S.A. DE C.V., ("Bestel") represented hereof by its
legal representatives, Messrs. Ignacio de J. Romo Davila and F. Xavier Basave
Gonzalez, pursuant with the following recitals and clauses:

                                    RECITALS

     1. Maxcom states, that:

         A.       It is a stock company duly incorporated and existing in
                  accordance with the laws of the United Mexican States pursuant
                  to public instrument number 86,115 dated February 26, 1996,
                  granted before Mr. Ignacio Soto Borja, with the original
                  corporate name of Amaritel, S.A de C.V. Subsequently, as
                  evidenced through public instrument No. 55,145 dated February
                  9th,1999, passed before the certification of Mr. Miguel
                  Alessio Robles, Public Notary No. 19 for Federal District the
                  corporate name was changed to the one it currently holds, as
                  such public instrument was also duly recorded before the
                  Public Registry of Commerce of the Federal District, file No.
                  210585.

         B.       Its legal representatives have the necessary capacity to enter
                  into this Agreement, as evidence in the public instrument No.
                  111,911 dated August 7th, 2001, passed before the
                  certification of Mr. Ignacio R. Morales Lechuga, Public Notary
                  No. 116 of the Federal District, and recorded in file No.
                  210582 before the Public Registry of Commerce of the Federal
                  District, and such capacity has not been revoked or limited
                  whatsoever.

         C.       It has the right to operate a public telecommunications
                  network in Mexico according to a Grant issued by the SCT
                  (Mexican Ministry of Communications and Transportation) on
                  December 20th, 1996 ("Maxcom's Concession").

         D.       It has the intention to acquire from Bestel the Fiber Optic
                  under the terms and conditions stated in this Agreement.

     2. Bestel states, that:

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                                                             English Translation

         A.       It is a stock company duly incorporated and existing in
                  accordance with the laws of the United Mexican States, with an
                  original corporate name of CABLEADOS Y SISTEMAS, S.A. DE C.V.,
                  as evidence in public instrument No. 33,515 dated August 1st,
                  1995, granted before the certification of Mr. Teodoro
                  Gutierrez Garcia, Public Notary 70 for Guadalajara, Jalisco.
                  Subsequently, as evidenced through public instrument No.
                  55,145 dated February 9th, 1999, passed before the
                  certification of Mr. Miguel Rabago Preciado, Alternate Public
                  Notary No. 42 for Guadalajara, Jalisco the corporate name was
                  changed to the one it currently holds, as such public
                  instrument was also duly recorded before the Public Registry
                  of Commerce of Guadalajara under file No. 177 - 178, Volume
                  586, Book First and number 146, Volume 613, Book first,
                  accordingly.

         B.       Its legal representatives have the capacity to force it in
                  accordance with the terms of this Agreement and such capacity
                  has not been revoked or modified whatsoever, as evidenced in
                  public instrument No. 22,490 dated February 26th, 1999 passed
                  before the certification of Mr. Javier Lozano Casillas,
                  Alternate Public Notary No. 58 from Guadalajara, Jalisco.

         C.       Bestel's corporate purposes authorize the execution of this
                  type of transaction and to enter the same it has the right to
                  install, keep, maintain and exploit a multiple system of fiber
                  optic Ducts, as well as the right to market such systems along
                  an extension of 2,250 kilometres of "Bestel's Rights of Way"
                  according to: (i) the Agreement entered into by and between
                  FNM (Ferrocarriles Nacionales de Mexico) and Bestel, dated
                  December 20th, 1996 (the "Bestel/FNM Agreement") and (ii) the
                  Authorization issued to Bestel by SCT on March 12th, 1997 (the
                  "Bestel's Authorization").

         D.       It has the right to operate a public telecommunications
                  network in Mexico in accordance with the Grant issued by the
                  SCT on January 8th, 1996. (the "Bestel Concession").

         E.       This Agreement does not confer any right in respect to
                  Bestel's permits referred to above, and therefore it is
                  Bestel's intention to sell to Maxcom the Fibers under the
                  terms and conditions set forth herein.

     3. Both parties state that:

         A.       On July 24th, 2002, Bestel and Maxcom entered into an
                  agreement in principle to purchase and sale the Fibers (the
                  "Letter of Intent") that is being formalized through this
                  Agreement, and therefore it is the

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                                                             English Translation

                  intention of this agreement to detail the rest of the terms
                  and conditions previously agreed by both parties.

By virtue of above mentioned statements and recitals, both parties agree to the
following:

                                    CLAUSES:

     1. DEFINITIONS AND EXHIBITS.

     1.1- The following definitions will be used during this Agreement:

         "Bestel Authorization" shall have the meaning ascribed to such term in
the Recitals.

         "Forks" or "Derivations" Points in the Bestel Network which may be used
for the derivation of the "Fiber" toward the localities or sites required by
Maxcom.

         "Letter of Intent" means the document executed by and between Maxcom
and Bestel dated July 24th, 2002, through which both parties agreed the Fiber
purchase and sale.

         "Bestel/FNM Agreement" shall have the ascribed to such term in the
Recitals.

         "Bestel Concession" shall have the ascribed to such term in the
Recitals.

         "Maxcom Concession" shall have the ascribed to such term in the
Recitals.

         "Collocations" are the spaces that Bestel will grant to Maxcom and
which are described in Section 3.2, paragraph C of this Agreement.

         "Minimum Maintenance Fee" shall have the meaning ascribed to such term
in Section 10.1 herein.

         "Duct" shall mean the Duct that holds the Fibers, object of this
transaction, built in accordance with the Bestel/FNM Agreement and the Bestel
Authorization and the Right of Way that runs along the routes and cities
described in Exhibit C herein.

         "Fiber Specifications" shall mean the fiber specifications to be
acquired by Maxcom and which are detailed in Exhibit B.

         "Acceptance Date" shall have the meaning described in Section 8.3
herein.

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                                                             English Translation

         "FNM" shall have the ascribed to such term in the Recitals.

         "Fibers" shall mean 2 (TWO) dark Fiber optic strands specifically
identified and purchased by Maxcom from Bestel in accordance with the terms of
this Agreement, located in the same fiber optic cable that Bestel operates and
holds its own fiber optic strands that run through the Duct along the cities
mentioned in Exhibit C.

         "Fibers System Acceptance" shall have the meaning described in Section
8.1 hereof.

         "Points of Presence" Main point of presence in the Bestel Network for
the delivery of long distance and metropolitan fiber facilities, when
applicable.

         "Regeneration Point" Secondary points of presence in the Bestel Network
required for the regeneration of signals from the electronic transportation
equipment.

         "Losses" shall have the meaning described in Section 14.1 hereof.

         "Purchase Price" shall mean the consideration payable by Maxcom to
Bestel under Section 3.1 hereof.

         "Network" shall mean the fiber optic telecommunications network
property of Bestel within the Mexican Republic, further described in detail in
Exhibit C hereof.

         "Fiber Systems" shall mean the dark fiber optics system comprised by
the Fibers, the lease of the Duct and the corresponding collocation spaces, as
well as the other parts related to the same, including the use of the
corresponding Rights of Way, as agreed and in accordance with this Agreement.

         "SCT" shall have the ascribed to such term in the Recitals.

         "Confidential Information" shall have the meaning described in Section
23 hereof.

         "Duct and Collocations Lease" shall have the meaning described in
Section 11 hereof.

                  The following exhibits are an integral part to this Agreement
and are listed below:

         EXHIBIT A: Collocations:

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                                                             English Translation

                  a) Specifications

                  b) Addresses

                  c) Schematic Drawings

         EXHIBIT B: Fiber Optic Specifications

         EXHIBIT C: Network Map

         EXHIBIT D: Physical Network Distances

         EXHIBIT E: Access Protocol for Collocations

         EXHIBIT F: Acceptance Protocol

                  a) Collocations

                  b) Fiber

         EXHIBIT G: Maintenance Procedures for Internal and Outside Plant.

         EXHIBIT H: Escalation Procedures

     2. FIBER PURCHASE AND SALE AND TERM

          2.1 Bestel sells to Maxcom, who purchase from Bestel the Fiber System
     that includes 2 (TWO) dark Fiber Optics strands (the "Fibers") through the
     route described in Exhibit C hereof and that runs through the collocations
     spaces described in Section 3.2, paragraph C hereof. The fibers shall be
     identified individually in one of the exhibits of the document that will
     contain the Acceptance of the Fiber System that the parties will execute in
     accordance with Section 8 of this Agreement, and that for purposes of
     identifying the Fibers shall form an integral part of this Agreement.

          Maxcom acknowledges and agrees that Bestel is not providing anything
     is not obligated to provide to Maxcom any electronic element or optic
     equipment in connection with the Fibers, all of which are the exclusive
     responsibility of Maxcom.

          The property of the Fibers as well as the real and legal delivery of
     the Fibers shall pass to Maxcom upon the execution of this Agreement. The
     Duct, the Collocation spaces, as well as the other assets and equipment
     that comprise the Fiber System shall only be leased to Maxcom by Bestel in
     accordance and connection with the terms of this Agreement and for the
     purposes related to the use of the Fiber System, without creating any other
     rights to Maxcom from that of a lessee.

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                                                             English Translation

          The Fiber System has an approximate length of 2,011 (Two Thousand
     Eleven) kilometres and the same is detailed with its routes and
     collocations described in Section 3.2, paragraph C hereof.

         The Fiber System includes the Duct and collocation spaces leases in the
     sites described in Section 3.2., paragraph C hereof that will hold Maxcom's
     equipment for the operation of the Fibers. Each collocation space to be
     used by Maxcom as lessee shall have an approximate area of 6 (SIX) square
     meters. Maxcom shall have access to the collocation spaces 24 (TWENTY FOUR)
     hours a day, the 365 (THREE HUNDRED SIXTY FIVE) days of the year, in
     accordance with the policies and procedures that Bestel has established for
     security reasons, the same that are included in Exhibit E herein. The
     collocation spaces include among others services, electric energy systems,
     air conditioning, fire systems and security 24 (TWENTY FOUR) hours a day,
     and which are further detailed in Exhibit A.

         2.2 Term: Bestel acknowledges that it has the title of the
corresponding rights of way for the operation of the Fiber System for a period
of 20 (TWENTY) years, and therefore undertakes the obligation to make the right
of ways, permits and other assets that conform the Fiber System available to
Maxcom during such period. In the event of an extension of the grant, the rights
of way and permits of Bestel, the term of this Agreement shall be automatically
be extended for a similar period, provided however that the cost associated with
such extension shall be covered on a pro - rata basis in connection with the
number of Maxcom Fibers allocated in the Bestel cable (this is, 3.33%).

         Notwithstanding the foregoing, both parties agree that in the event
receives the notification of the commencement of a procedure for the recession
of the Bestel/FNM Agreement, Bestel shall notify Maxcom of such situation within
the following 2 (TWO) days, in order for Maxcom to initiate with Bestel express
consent in term of this clause all acts necessary in order for Maxcom to acquire
the title, in proportion with the number of fiber optic strands owned by Maxcom,
of all rights derived from the Bestel/FNM Agreement as well as the Bestel
Authorization that may be required by Maxcom for keeping the operation and use
of the Fiber System in accordance with the terms of this Agreement.

     3. PURCHASE PRICE.

     3.1 Both parties agree that the purchase price for the Fiber System is the
     amount of US$10,900,000 (Ten Million Nine Hundred Thousand Dollars and
     00/100), currency of the United States of America, plus the corresponding
     value added tax ("VAT"), purchase price that includes the elements and
     routes described herein:

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                                                             English Translation

         -        The corresponding segment of the route of Mexico City, D.F to
                  Laredo, Tx., including the bordercrossing between this last
                  city and the city of Nuevo Laredo, Tamps., running through the
                  populations detailed in Exhibit C hereof;

         -        The Irapuato, Gto., derivations to Guadalajara, Jal., and the
                  derivation from Mexico City, D.F. to the city of Toluca, State
                  of Mexico, running through the populations detailed in Exhibit
                  C hereof;

The foregoing routes totalling an approximate distance of 2,011 (Two Thousand
Eleven) kilometres.

         The agreed purchase price, includes:

         A.- 2(TWO) dark Fiber Optics in the rural and sub-urban routes along
the cities described in the paragraph C below;

         B.- 2 (TWO) dark Fiber Optics in the metropolitan routes to access
Bestel sites and the manholes or handholes located in front of the Telmex
Telephone Central Office where Bestel is interconnected, in each one of the
cities described in paragraph C below, as well as the sub - urban routes
required to access the Regeneration Points;

         C.- The 20 (TWENTY) year lease, and its extensions, of the proportional
part of the Duct in which the Fibers are housed and the collocation spaces with
an approximate area of 6 (SIX) square meters in the following cities and towns:

                  i. Laredo, Texas                 Point of Presence (without
                                                   connection to Telmex Central
                                                   Office)
                  ii. Candela                      Regeneration Point.
                  iii. Monterrey                   Point of Presence.
                  iv. Saltillo                     Point of Presence.
                  v. El Salado                     Point of Presence.
                  vi. Laguna Seca                  Point of Presence.
                  vii. San Luis Potosi             Point of Presence.
                  viii. Salinas                    Point of Presence.
                  xi. Aguascalientes               Point of Presence.
                  x. Leon                          Point of Presence.
                  xi. Irapuato                     Point of Presence.
                  xii. Celaya                      Point of Presence.
                  xiii. Queretaro                  Point of Presence.
                  xiv. Toluca                      Point of Presence.

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                                                             English Translation

                  xvii Yurecuaro                   Regeneration Point.
                  xviii. Guadalajara               Point of Presence.

     4. PAYMENT AND GUARANTY.

     4.1 The purchase price of the Fiber System shall be paid to Bestel in
accordance with the following:

         a.-      The equivalent to 60% (SIXTY PERCENT) of the total
                  consideration, this is the amount of US$6,540,000 (Six Million
                  Five Hundred Forty Thousand Dollars and 00/100), currency of
                  the United States of America, plus the corresponding VAT shall
                  be paid and delivered within the 24 (TWENTY FOUR) hours
                  following the execution of this Agreement, provided however
                  that the firs notification for the funds release ("First
                  Release Notice", as such term is defined in the Escrow) shall
                  be subscribed by the parties simultaneously with the execution
                  of this Agreement.

         b.-      The equivalent to 40% (FORTY PERCENT) of the balance of total
                  consideration, this is the amount of US$4,360,000 (Four
                  Million Three Hundred Sixty Thousand Dollars and 00/100),
                  currency of the United States of America, plus the
                  corresponding VAT shall be paid and delivered upon the
                  Acceptance of the Fiber System in accordance with the
                  procedures and acceptance protocols mentioned in Exhibit F
                  hereof.

     All payments made by Maxcom in accordance with this Agreement shall be
delivered free and clear of any and all liens or ownership restriction.

     4.2 Maxcom created in accordance with the terms of the Letter of Intent a
guaranty deposit ("Escrow") for a total amount of US$10,900,000 (Ten Million
Nine Hundred Thousand Dollars and 00/100), currency of the United States of
America, plus the corresponding VAT. The funds in the Escrow shall be released
by the "Escrow Agent" in terms of Section 4.1 hereof as well as in accordance
with the release mechanisms provided for in such Escrow. Additionally, in terms
of the Letter of Intent and in accordance with a previous notice from Bestel,
dated July 22, 2002, Bestel informed Maxcom and Maxcom acknowledged that the
collection rights derived from the purchase and sale of the Fiber System
correspond to "Proveduria de Servicios Administrativos Profesionales de
Occidente, S.A. de C.V." ("Prosapo"), as per an assignment of collection rights
agreement executed by and between Bestel and Prosapo.

Maxcom acknowledges that the Escrow above mentioned, does not release Maxcom
from its payment obligation under this Agreement; and Maxcom specifically

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                                                             English Translation

acknowledges any and all responsibilities for the loss of value of the funds
invested by the Escrow Agent, unless such loss of value is attributable directly
to either Bestel and/or Prosapo.

     4.3 Maxcom and Bestel are compelled to execute and deliver to the Escrow
Agent simultaneously with the execution of this Agreement, the first release
notice for the funds release ("First Release Notice", as such term is defined in
the Escrow), so that the Escrow Agent releases the fund to cover the payment of
60% (SIXTY PERCENT) of the total funds, as mentioned in subparagraph (a) of
Section 4.1 above.

     4.4 Likewise, within 2 (TWO) working days as of the Acceptance Date, the
parties must execute and deliver to the Escrow Agent, the second release notice
for the funds release ("Second Release Notice", as such terms is defined in the
Escrow), so that the Escrow Agent releases the funds to cover the payment of 40%
(FORTY PERCENT) of the total funds, as mentioned in subparagraph (b) of Section
4.1 above.

In the event that Maxcom doesn't subscribe the second release notice within the
terms mention in the paragraph above, for causes directly attributable to
Maxcom, notwithstanding the tests for the Acceptance of the Fiber System were
completed in accordance with Section 8 below, Maxcom shall pay Bestel a penalty
equal to US$10,000 (Ten Thousand Dollars and 00/100), currency of the United
States of America per day of delay for a term of 21 (Twenty one) days and until
the second release notice is delivered. Maxcom may not deny without reasonable
and justifiable cause the acceptance to the Fiber System in terms of Section 8.2
below.

Following the 21-day period referred above, Maxcom shall pay to Bestel a penalty
equal to 20% (Twenty percent) of the Purchase Price, on the understanding that
this penalty is in addition to the one referred on the preceding paragraph. In
the case of this event, Bestel shall have the right to a) rescind this
Agreement, without the previous judicial declaration, reimbursing Maxcom the
amount referred to in subparagraph a) of Section 4.1 hereof, without any further
responsibility to Bestel or b) negotiate with Maxcom the terms and conditions
applicable to the delivery of the second release of funds notice ("Second
Release Notice", as such terms is defined in the Escrow).

The abovementioned penalties shall not apply in the case that the delay in the
delivery of the second release of funds notice is for causes not directly
attributable to Maxcom, for acts of God or force majeaur or causes directly
imputable to Bestel.

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                                                             English Translation

     5. ADDITIONAL EXPENSES.

         5.1 Forks and Derivations.- Maxcom shall have the right to carry out up
to 100 (ONE HUNDRED) forks or derivations of the Fibers along the Fiber System
route with a cost or fee per fork or derivation of [*] currency of the United
States of America, plus the corresponding VAT. This cost will be paid by Maxcom
to Bestel when the works required for each of the forks or derivations have been
duly completed.

In addition to the abovementioned fee, Bestel will charge to Maxcom: (i) the
amount of [*] currency of the United States of America, plus the corresponding
VAT for the first 2 (TWO) supervision or consultancy hours related to the
derivation or fork and; (ii) [*] currency of the United States of America, plus
the corresponding VAT, for any additional hour. The above mentioned fares
include the cost for the splicing and connecting the Bestel fibers optic strands
and the Maxcom fibers optic strands, and this works shall only be performed by
Bestel or personnel authorized or hired by Bestel.

Bestel is compelled to exclusively carry out the fiber optic cuts and splicings
of the Fibers in the terms required by Maxcom as well as any other works
required on the Manholes or Handholes that are part of the Network, including
the supervision of the constructions that Maxcom will make (at its
responsibility and cost) from

Bestel's Manholes or Handholes, that will be the physical place where the fiber
cut and splicings will be carried out, and that shall also be the fork or
derivation points for Maxcom and to Maxcom's Manholes or Handholes that shall be
placed no less than 1 meter from any other element of the Network.

Maxcom and Bestel shall agree on good faith basis on the terms to carry out the
required construction and works mentioned in the preceding paragraphs in
accordance with terms and conditions similar to those required for this type of
services pursuant to best international practices. In case that Bestel does not
comply with the cut and splicing of the Fiber in the agreed upon term, Bestel
shall pay to Maxcom a penalty equal to [*] currency of the United States of
America per day of delay.

________________

[*] This amount has been omitted pursuant to a request for confidential
treatment. The omitted material has been filed separately with the U.S.
Securities and Exchange Commission pursuant to Rule 24b-2 under the Securities
Exchange Act of 1934.

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                                                             English Translation

         5.2. Relocation Costs.- Any cost related with the fiber System
relocation given as a result of a governmental order, of the grantor of the
right of ways, or for security matters related to the Fiber System shall be
covered by the owners of Fibers in the Fiber System on a proportional basis. In
such event, Maxcom shall pay such costs (3.33% of the total) immediately upon
receiving Bestel's request. Bestel shall present to Maxcom a detailed expenses
and costs list, at Maxcom's request. Bestel shall make its best effort to avoid
any unnecessary relocation.

     6. PERMITS.

In connection with the segments to be built in the future within the rights of
way obtained by Bestel for the Network construction, Bestel agrees that, upon
Maxcom's request, Bestel shall negotiate on Maxcom's name and behalf or in
Bestel's name but at Maxcom's behalf, with the railroad companies holders of the
rights of way, the SCT, and with any other third parties, obtaining the permits
related to construction works required by Maxcom to interconnecting its Fibers
to its own telecommunications network, as well as to carry the Fiber Forks and
Derivations referred to above. The costs generated for the delivery of such
supports or assistance to Maxcom, including the assignment of to its own staff
for these functions, will be presented to Maxcom for its previous authorization,
and when the same have been completed, Maxcom shall reimbursed such costs to
Bestel immediately. Notwithstanding the foregoing, prior to the rendering of
such services, Bestel shall have the right to request Maxcom for a reasonable
retainer in accordance with the budget submitted by Bestel for this purposes.
Both parties acknowledge that Bestel shall not be bound, nor shall it be its
responsibility that the management performed by Bestel results in the granting
to Maxcom of the corresponding permits; however, Bestel acknowledges and agrees
to make it best effort to obtain favourable results to Maxcom.

Maxcom, knowledgeable of the regulations in the subject matter, is responsible
for obtaining the corresponding permits required for the use and exploitation of
the Fiber System.

     7. COLLECTION RIGHTS.

Maxcom and Bestel agree and acknowledge that the total collection rights derived
from this Agreement are the exclusive property of Proveduria de Servicios
Administrativos Profesionales de Occidente, S.A. de C.V. ("Prosapo"), in
accordance with the assignment of collection rights agreed upon Prosapo and
Bestel and notified to Maxcom on July 22, 2002. Notwithstanding the foregoing,
Bestel shall be bound to Maxcom to comply with its obligations in the agreed
upon terms and conditions.

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                                                             English Translation

     8. FIBER SYSTEM ACCEPTANCE.

     8.1. Bestel shall submit the Fibers to a test for tranches or segments of
the route and the collocations in each place according to the procedures
detailed in Exhibit F hereof ("Fiber System Acceptance") to verify that Fiber
System is working according to the specifications of the Fibers and the
collocations. Bestel and Maxcom shall agree on the tests schedule of Fiber
System Acceptance within the following 2 (TWO) working days after the execution
of this Agreement, so that, Maxcom has the opportunity to have a representative
or representatives present and observe the tests of Fiber System Acceptance.

     The execution of the tests of the Fiber System Acceptance shall finish no
     later than 30 (THIRTY) working days following the execution of this
     Agreement. If at the end of such period of 30 (THIRTY) working days the
     Fiber System Acceptance has not been completed due to errors or
     deficiencies imputable to Bestel, and that such errors or deficiencies
     impede Maxcom the total use of the Fiber System, the following shall occur:

         i)       During the first 21 (Twenty one) working days of delay, Bestel
                  shall pay Maxcom, as penalty, the amount of US$10,000 (Ten
                  Thousand Dollars and 00/100), currency of the United States of
                  America per day of delay; and

         ii)      If the delay continue at the end of the period of 21 (Twenty
                  one) working days mentioned in the foregoing paragraph, Bestel
                  shall pay Maxcom as penalty, the amount equivalent to 20%
                  (Twenty percent) of Purchase Price, on the understanding that
                  this amount is in addition to the penalty referred to in the
                  preceding paragraph i).

In the event of paragraph ii) above, Maxcom shall have the right to a) rescind
this Agreement without need of a court order and request the reimbursement of
the amount referred to in section 4.1, subparagraph a), without any
responsibility to Maxcom, or b) negotiate with Bestel the terms and conditions
applicable to the Fiber System Acceptance.

The abovementioned penalties shall not be applicable in case the delay in the
Fiber System Acceptance is for causes not directly imputable to Bestel, acts of
God, force majeure.

     8.2. Once Maxcom and Bestel have determined that the results of the tests
for the Fiber System Acceptance show that the Fibers tested are suitable for
operation, in accordance with the Fiber Specifications, Bestel shall immediately
provide to Maxcom a copy of the tests results so that Maxcom may sign accepting
such tests and results in accordance with Exhibit F hereto.

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                                                             English Translation

     8.3. Once the tests are made and the Fiber System has been accepted by
Maxcom in accordance with Section 8.2 above, Bestel and Maxcom shall execute a
final document that shows that the acceptance and delivery procedures of the
Fiber System were duly concluded. The issuance date of such document shall be
considered as the "Acceptance Date" of the Fiber System and shall be the date in
which the parties shall sent the instructions referred to in Section 4.4 of this
Agreement to the "Escrow Agent" for the release of 40% of the funds of the Total
Payment. Notwithstanding the foregoing, the parties acknowledge the possibility
that as of the Acceptance Date there may be minor errors or deficiencies pending
to be delivered or corrected that in no event shall interfere with the proper
use of the Fiber System. In this event, the parties shall identify in the
document mentioned in the preceding paragraph the minor errors or deficiencies
that may exist as of the Acceptance Date, as well as the terms and conditions
applicable for its completion or correction by Bestel, including the
corresponding penalties for non compliance. The additional term for the
completion or correction for such minor errors or deficiencies shall in no event
be a motive for retaining the payment of 40% (FORTY PERCENT) of the purchase
price mentioned in this Section 8.3 and in Section 4.1 of this Agreement.

For purposes of the release of 40% of the Total Payment referred to in the
preceding paragraph, Bestel and Maxcom expressly agree that the collocation
sites in the cities of Laredo, Texas, Leon, Gto., Celaya, Gto. and Queretaro,
Qro. shall be delivered by Bestel within the following 4 (four) weeks of the
"Acceptance Date". Notwithstanding the foregoing, Bestel shall provide to Maxcom
at no additional cost a provisional collocation space in the abovementioned
sites with all the facilities required to hold Maxcom's telecommunication
equipment related to the Fiber System. The term for the delivery of the referred
collocation sites shall in no event be considered a cause for holding the
payment of 40% (FORTY PERCENT) of the purchase price mentioned in Section 8.3
and in Section 4.1 of this Agreement.

     9. ACCESS TO THE COLLOCATION SITES.

     9.1 Bestel shall grant to Maxcom (or to the party or parties appointed by
it) the access to the collocation sites leased to Maxcom as part of Fiber System
located in the cities of Laredo, Texas, Candela, Monterrey, Saltillo, El Salado,
Laguna Seca, San Luis Potosi, Salinas, Irapuato, Nopala, Aguascalientes, Leon,
Celaya, Queretaro, Mexico, Toluca, Yurecuaro and Guadalajara.

     9.2 Bestel shall provide to Maxcom (or to the party or parties appointed by
it) access to the collocation sites leased to Maxcom, and Maxcom shall have the
right to connect, at its own expense and risk, its telecommunication network
with the Fibers in each of the cities named on paragraph 9.1 above.

                                       14

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                                                             English Translation

     10. MAINTENANCE AND REPAIR OF THE NETWORK

     10.1 Bestel shall have the sole right and obligation to maintain the
Fibers, and therefore Bestel shall undertake or order that such maintenance be
provided in accordance with preventive and corrective maintenance procedures
established by Bestel, and which results shall be periodically reported to
Maxcom.

As consideration of such maintenance services, Maxcom shall pay to Bestel a
minimum annual maintenance fee of [*] currency of the United States of America,
plus the corresponding VAT, per par of fiber optic kilometres. This fee shall be
adjusted annually by Bestel, in accordance with the annual inflation recognized
by the Consumer Price Index (CPI), published by the U.S. Labor Department or the
index replacing the same, shall it be the case.

In the event that Bestel reduces in a general manner, due to future sales of
infrastructure, the maintenance costs, Bestel shall extend such benefit to
Maxcom upon approving the new maintenance fee.

The Maintenance Services shall be paid by Maxcom quarterly in arrears.

Bestel acknowledges the first 180 (ONE HUNDRED EIGHTY) days, as of the execution
date of this Agreement, shall bear no maintenance fee.

     10.2 Bestel shall carry out the repairs and maintenance of the Fibers in
accordance with the Escalation and Maintenance procedures detailed in Exhibits G
and H.

     10.3 Within the following 30 (THIRTY) days after the execution of this
Agreement, Bestel and Maxcom shall negotiate in good faith the terms,
conditions, procedures and scopes of the Exhibit G regarding maintenance of the
Fiber System, being such Exhibit G a precondition for the Acceptance of the
Fiber System.

     10.4 In any event, the payment of the Maintenance Fee shall be subject to
delivery of monthly maintenance reports by Bestel.

     10.5 Exhibit G shall have the level service and penalty levels contained in
the Attachment 2 (Operator's Undertakings) of the Letter of Intent, which shall
be applicable also for the electric energy system of the collocation sites.

____________

[*] This amount has been omitted pursuant to a request for confidential
treatment. The omitted material has been filed separately with the U.S.
Securities and Exchange Commission pursuant to Rule 24b-2 under the Securities
Exchange Act of 1934.

                                       15

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                                                             English Translation

     11. DUCT AND COLLOCATION SITES LEASE

     11.1 As of the Acceptance Date described in Section 8.3, Bestel hereby
grants to Maxcom: (a) the lease of the proportional part of Duct that will hold
the Fibers in the Bestel Network, in accordance with the terms established in
this Agreement and for the purposes herein described; (b) the lease of the
collocation sites described herein and (c) any other right inherent or necessary
for the use of the Fibers System on the terms of this Agreement (the "Duct and
Collocation Lease").

     11.2 The Duct and Collocation Lease shall be become effective as of the
Acceptance Date and shall end at the termination of this Agreement.

     12. USE OF THE FIBERS

     12.1 Maxcom declares that it will use the Fibers in accordance with all
applicable governmental codes, decrees, laws, rules and regulations.

     12.2 Bestel agrees and acknowledges that it does not have the right to use
the Fibers, and that Bestel will maintain the Fibers free and clear of (a) any
encumbrance of a third party which may be attributable to Bestel, and (b) any
claim or complaint of third parties attributable to Bestel.

     12.3 Subject to the terms and conditions herein, Maxcom may use the Fibers
for any legitimate telecommunications purpose. Maxcom agrees and acknowledges
that it does not have the right to use any fibers, that are not the Fibers,
included on the Network, and that Maxcom shall maintain any part and all the
Network, different to the Fibers and its interest pursuant to the lease of the
Duct and of the Collocations, free and clear of any claims of third parties
attributable to Maxcom.

     12.4 Maxcom and Bestel immediately shall notify each other of any matter
related to, or that arise (or of any imminent event), from any event or
happening that would be reasonably probable to occur that may arise or may
originate a threat or damage or threat of damage or loss of the Network.

     12.5 Bestel and Maxcom agree to collaborate and support mutually in the
fulfillment of any applicable requirement related to its corresponding rights
and obligations derived from this Agreement that may be required by any
authority or governmental agency.

     13. REPRESENTATIONS AND WARRANTIES

     13.1 Each of the parties in this Agreement makes the following
representations and warranties:

                                       16

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                                                             English Translation

         (a) has the full right and capacity to enter into, formalize, grant and
fulfill with all of its obligations in accordance with this Agreement and that
they have not breached any clause of the Authorizations, Grants or concessions
or permits of the SCT or its Agreements with FNM, and that the rights derived by
such legal documents remain in full force and effect.

         (b) the execution of this Agreement and its fulfillment does not breach
any regulation, rule, statute, law of any governmental agency, court order or
federal, local or municipal agency disposition.

         (c) Maxcom shall not use the Fibers in any manner that may interfere
physically in may adversely affect the use of the fibers of ay other person that
may use the Network, and shall expressly acknowledge that the Network includes
or may include other participants, including Bestel and other owners and holders
of other interests and telecommunication system operations. Bestel shall not use
any other fibers in the Network in any manner that may interfere physically in
may adversely affect the use of the Fibers and shall obtain a similar
representation and warranty from any person that may acquire the right to use
fibers in the Network after the execution of this Agreement, and,

         (d) Maxcom represents and warrants that it knows and is conscious and
it will be the sole responsible to obtain each and all the authorizations,
permits and concessions that may be required so that can be owner of dark fiber
optics, and shall it be the case, operator of the same, notwithstanding the
obligations of Bestel to maintain in full force and effect all of the rights of
Maxcom derived from this Agreement and all of its terms.

     13.2 Bestel represents and warrants that:

         (a) The Fibers System is totally finished and ready to use, except for
the collocation sites in the cities of Laredo, Texas, Leon, Gto., Celaya, Gto.,
and Queretaro, Qro., which shall be delivered by Bestel within the following 4
(four) weeks after the Acceptance Date. Notwithstanding the foregoing, Bestel
shall provide to Maxcom, provisionally and free of any charge, space in the
mentioned places with equated facilities for the installation of the
telecommunication equipment that shall be used by Maxcom in connection with the
Fibers System. The additional term for the delivery of the collocation sites
referred to above shall in no event cause the holdback of the 40% (FORTY
PERCENT) of the purchase price mentioned in Section 4.1 subparagraph b of this
Agreement.

         (b) Bestel shall extend to Maxcom all the benefits of the guarantees
that its suppliers extended to Bestel during the construction of the Fibers
System, in their proportional part, as long as the same are still in full force
and effect.

                                      17

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                                                             English Translation

         (c) The Fibers System and the Network are free and clear of any
seizure, mortgage, pledge, guarantee trust or any other lien or ownership
restriction and Bestel has full capacity to transfer the title and property of
the Fibers to Maxcom, grant the Duct and Collocation Lease and enter into this
Agreement in its terms.

         (d) The execution of this Agreement does not breach or is against the
agreements, deals and settlements to which Bestel is a party, nor does it breach
or is against or beyond the Bestel bylaws (ultra vires acts), nor does it breach
or is against any governmental disposition, permit, concession or authorization,
nor does it breaches or is against any judgment or court order of Bestel,
including the Bestel/FNM Agreement and the Bestel Authorization.

         (e) There is no litigation or potential litigation of Bestel that
Bestel may know of (after doing a reasonable research) that might endanger or
threat Maxcom's right to use and enjoy the Fibers system in the terms hereof.

         (f) The Fibers System is in good conditions and with full capacity of
use in the terms agreed hereof.

     14. INDEMNIFICATION

     14.1 Each one of the parties agree to hold the other party harmless of any
and all Losses (as such term is defined hereinafter) that such party may have
suffered, and shall indemnify and held free and clear of any damage such party
of any Losses that may arise or are related to (1) any breach of any agreements,
arrengaments or obligations that are required to be complied with in accordance
with this Agreement, with the Bestel/FNM Agreement and the Bestel Authorization,
or (2) any material misrepresentation made under this Agreement. For purposes of
this Agreement, "Losses" shall mean all the damages and direct losses that are
actually disbursed.

     14. 2 If any party expects to obtain an indemnification in accordance with
this section, such party shall notify the other party of any complaint, within
fifteen (15) days after the discovery of such event and shall provide to the
other party any aid and reasonable information available for the party's defense
of any such allegations.

     15. MAXCOM AND BESTEL ADDITIONAL OBLIGATIONS

     15.1 If Maxcom or any of its affiliates or successor becomes total or
partial owner or in another way controls a railroad in Mexico, Maxcom shall
cooperate with Bestel and shall make its commercially reasonable best efforts to
give access to the Bestel Rights of Way, in terms and conditions at least as
favorable as those granted to Bestel by the preceding owner or by the party
controlling the railroad.

                                       18

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                                                             English Translation

     15.2 Insurance. Maxcom and Bestel shall obtain and maintain in force and
effect, each one at its expense and during the term of this Agreement, a third
parties liability insurance and for any risks associates with the Fibers System
which must have a minimum insurance coverage of US$5,000,000.00 (Five Million
Dollars 00/100) currency of the United States of America which will be adequate
to protect against responsibilities and losses and complaints regarding death or
wound of a person or in event of loss, damages and consequential damages to any
property that might be derived or be consequence of or it is in relation to the
use of the Fibers System. Additionally, the parties must appoint as additional
beneficiary of such insurance policy the other party and shall establish in the
same that this appointment may not be cancelled without previous notice of the
other party. The parties must deliver each other copy of the insurance policy
and of their corresponding renewals and endorsements, within the following
working 5 (FIVE) days following the delivery of the Fibers System.

     16. BREACHES AND REMEDIES

     16.1 In connection with all payments that the parties are required to make
in relation with this Agreement, if any party breaches to make a payment to the
other party, the amounts not paid shall generate, until paid in full, an annual
interest rate equal to the Libor Rate times 2, when the amount due is in dollars
and an annual interest rate equal to the Interbank Equilibrium Interest rate
times 2, when the amount due is in pesos. In the event that any due amounts
remain unpaid for a period of thirty (30) days after due, then affected party
may, at its sole and absolute discretion and in addition to the rest of its
rights and remedies in herein, terminate any and all obligations derived from
this Agreement without the need of a previous court order.

     16.2 Regarding the rest of its obligations according to this Agreement, if
Maxcom breaches to comply with an obligation of any other kind and such failure
continue during a period of more than thirty (30) days after Bestel has given a
written notice to Maxcom about such failure, Maxcom shall be in default in
accordance with this Agreement, unless Maxcom has corrected the breach or such
breach was waived in writing by Bestel within such thirty (30) days period.

Maxcom will be in default in accordance with this Agreement (a) automatically at
the moment when Maxcom executes a general assignment of assets for the benefig
of its creditors, if Maxcom is in any event of the Mexican Bankruptcy Law; or
(b) if a petition for bankruptcy has been presented against Maxcom and such
petition was not overruled within a period of one hundred and twenty (120) days.

Unless otherwise specified in this Section, when there is a breach by Maxcom
and, after Bestel has provided a written notice, Bestel may (a) initiate the
legal actions that may be required to correct the breach and recuperate from
Maxcom all the cost

                                       19

<PAGE>

                                                             English Translation

associated with the correction of such breach, including the rescission of this
Agreement, without the need of a prior court order and/or (b) obtain any legal
remedies that he might be entitled to obtain in accordance with applicable law
in connection with such breach.

     16.3 In connection with Bestel's obligations in accordance with this
Agreement, in the event that Bestel breaches any obligation hereof and if such
breach persists for more than thirty (30) days after Maxcom has given a written
notice to Bestel about such failure, Bestel shall be in default in accordance
with this Agreement, unless Bestel has corrected the breach or such breach was
waived in writing by Maxcom within such 30 day period, provided, however, that
when the breach may not be reasonably cured within such 30 day period, if Bestel
proceeds to cure such breach and continues to follow up on the correction with
due diligence, the period for such cure shall be extended as required, provided,
further, that if Bestel certifies in good faith to Maxcom in writing that the
breach has been cured, such breach shall be considered cured, unless Maxcom
notifies otherwise to Bestel within fifteen (15) days after receiving Bestel's
notice.

     Bestel will be in default in accordance with this Agreement (a)
     automatically at the moment when Bestel executes a general assignment of
     assets for the benefit of its creditors, if Bestel is in any event of the
     Mexican Bankruptcy Law; or (b) if a petition for bankruptcy has been
     presented against Bestel and such petition was not overruled within a
     period of one hundred and twenty (120) days.

     Unless otherwise specified in this Section, when there is a breach by
     Bestel and, after Maxcom has provided a written notice, Maxcom may (a)
     initiate the legal actions that may be required to correct the breach and
     recuperate from Bestel all the cost associated with the correction of such
     breach, including the rescission of this Agreement, without the need of a
     prior court order and/or (b) obtain any legal remedies that he might be
     entitled to obtain in accordance with applicable law in connection with
     such breach.

     Notwithstanding anything to the contrary in this Agreement, in the event of
     i) the rescission of the Bestel/FNM Agreement for causes imputable to
     Bestel and/or ii) by reason of such breach of Bestel, Maxcom may be impeded
     to use the Fiber System in the agreed upon terms of this Agreement, Bestel
     shall be responsible for the payment of any Losses suffered by Maxcom, the
     same that in no event shall be inferior to US$2,000,000 (Two Million
     Dollars and 00/100), currency of the United States of America.

     The parties agree that there shall exist a breach by one of the parties, in
     accordance with the foregoing, only in the case the breach actually affects
     the rights of the other party.

                                      20

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                                                             English Translation

     17. APPLICABLE LAW

     The rights and obligations of the parties hereof will be interpreted and
     translated according to Mexican Federal Laws.

     18. AMICABLE COMPOSITION AND ARBITRATION

     In the event a dispute arises for the breach or for the interpretation of
     this Agreement, the parties agree, that previous to the arbitration
     proceeding referred to in the following paragraph, to appoint a
     representative of each one of them, that will hold a level of director or
     similar, in order to mediate any differences in connection with this
     Agreement in a term not to exceed 30 (THIRTY) days. If the parties are
     unable to reach an amicable composition, the parties shall be bound in
     accordance with the following paragraph.

     All disputes, controversies or complaints that may result or are related to
     this Agreement or with the breach, termination or invalidity of the same
     shall be definitively resolved in arbitration. In such event, the parties
     are bound to a final and binding arbitration procedure, regardless to the
     jurisdiction that any other court jurisdiction may have in connection with
     either of the parties. Unless the parties agree otherwise in writing to
     held the arbitration by one (1) arbitrator, and they appoint such
     arbitrator individually, the arbitration procedure shall be managed by (3)
     three arbitrators, (1) one elected by Maxcom, (1) one elected by Bestel and
     the third one elected by the two (2) previously appointed arbitrators. The
     third appointed arbitrator shall preside over the arbitration panel. When
     the parties fail to appoint the arbitrator corresponding to them within
     fifteen (15) day following the date when the first of them appointed its
     arbitrator, or when the first two (2) arbitrators does not reach an
     agreement about the appointment of the third arbitrator, the arbitrator in
     question shall be assigned by Centro de Arbitraje de Mexico (CAM) as
     appointing authority. The arbitration shall be carried out in accordance
     with the Arbitration Rules of Centro de Arbitraje de Mexico (CAM) in force
     in that moment, as amended or modified in this Agreement. The arbitrators
     will have the capacity to impose precautionary measurements to keep the
     status quo or keep or protect the assets, decree the fulfillment of the
     obligations of one of the parties, in accordance with this Agreement, or
     impose monetary fines for disobedience of the party that resist to fulfill
     the Arbitration Award issued by arbitrators or in connection with their
     orders. The Arbitration Award will be definitive and of compulsory for both
     parties. Each party will bear its corresponding legal expenses, however,
     the rest of the costs and expenses associated with arbitration procedure,
     including the arbitrators fees, shall be divides and paid equally between
     the parties. The Arbitration Award may be submitted before any competent
     court, which may issue an execution order to enforce such Arbitration
     Award. The arbitrators would not any relation, neither shall they be
     employees of, nor will have considerable business relations in any

                                       21

<PAGE>

                                                             English Translation

     moment with some of the contracting parties, or with any of its affiliates.
     The arbitration shall be ruled by the Mexican Federal Laws. The arbitration
     shall take place in Guadalajara, Jalisco, and it shall be in Spanish. The
     parties shall submit themselves to the competent courts jurisdiction to
     enforce the arbitration award in accordance with the foregoing, in the
     event required, waiving to any other jurisdiction to which they have right.

     19. TAXES

     The parties acknowledge and agree that each one of them is responsible to
     pay the taxes and contributions to which each one of them is compelled to
     in accordance with applicable laws and regulations.

     20. NOTICES

     Any and all the notices that are required or permitted to give in
     accordance with this Agreement, will be written and will be delivered by
     fax, by personal service or courier service from one day to the next, or by
     delivery service that is capable of providing a proof of the delivery, in
     the following way:

     If they are sent to BESTEL: BESTEL S.A. de C.V.

                                 Atte: Mr. Xavier Basave Gonzalez
                                 Guadalupe Zuno 2051
                                 44160, Col. Americana, Guadalajara, Jalisco.
                                 Telephone No. (33) 3818-0141
                                 Fax No. (33) 3838-0180

                                 C.C. to the Attention of:
                                 Mr. Santiago Gutierrez Fernandez,
                                 Ejercito Nacional No. 579,
                                 Colonia Granada, 11520, Mexico, D.F.
                                 Telephone no. 5354-21-44
                                 Fax No. 5255-06-96.

     If they are sent to MAXCOM: Maxcom Telecomunicaciones, S.A. de C.V.
                                 Re: Mr. Rene Sagastuy Ferrandiz
                                 C. Guillermo Gonzalez Camarena No. 2000
                                 Col. Centro de Ciudad Santa Fe,
                                 Mexico, D.F., C.P. 01210
                                 Telephone No. 51 47 12 00
                                 Fax No. 51 47 8643

                                       22

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                                                             English Translation

                                    C.C. to the Attention of:
                                    Legal Department (same address)
                                    Telephone No. 51 47 11 20
                                    Fax no. 51 47 8645

     21. FORCE MAJEURE

     If it is prevented, restricted or interfered with the fulfillment of any
     party's duty or obligation according to this Agreement for any reason or
     circumstance beyond control of the non-complying party, then such party,
     notifying immediately to the other part shall not be responsible of such
     breach during the period of force majeure. For these purposes, the cases of
     force majeure include acts of God, or of the public enemy, vandalism acts,
     Government acts in its sovereign nature, fires, floods, hurricanes,
     earthquakes and the other natural disasters, epidemies, quarantines,
     strikes or seizures of property that in all event, are out of control,
     without fault or negligence, of the non-complying party. In the event of a
     delay in the execution of the obligations of the parties in accordance with
     this Agreement, that result from a case of force majeure, the date for the
     fulfillment of such obligation shall be extended during an period of time
     equal to the length of time that caused such delay, plus the additional
     time that may be reasonably necessary according to the circumstances.

     22. ASSIGNMENT

         22.1 Neither Party may assign total or partially its rights or
     obligations hereunder without the prior written consent of the other party.

     Bestel, even without Maxcom's consent shall be able to assign and/or
     discount with third parties the collection rights (Factoring) of the any
     amounts derived from this Agreement.

     In the event that Bestel attempts to assign total or partially the rights
     derived from Bestel/FNM Agreement and the Bestel Authorization, Bestel
     shall obtain, previously to the formulation of application to obtain the
     required authorizations in terms of the contractual and administrative
     dispositions that result applicable, the formal and express consent of the
     person that expect to acquire through such assignment the rights derived
     from Bestel/FNM Agreement and from the Bestel Authorization shall be
     required indicating it will comply and respect all and each one of rights
     of Maxcom herein and shall not interfere, in any way, with the use of its
     Fibers System.

     The parties acknowledge that the sale of all or the majority of their
     shares, a merger, incorporation or integration in any way to other company
     or business group may not be construed as an assignment. For purposes of
     this paragraph,

                                       23

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                                                             English Translation

     the authorization of the other party shall not be required and a
     notification of the sale of the shares or the merger, incorporation or
     integration shall be required within 5 (five) following days to the closing
     of such event.

         22.2 Maxcom may not transfer, assign, sublease, lease or in another way
     transfer or provided to thirds the property and/or Fibers System operation
     as a whole.

     23. CONFIDENTIALITY

         23.1 (a) Bestel and Maxcom hereby agree that if any of the parties
     provide (or has provided before the execution of this Agreement)
     confidential information or subject to intellectual property rights, to the
     other party ("Confidential Information") such Confidential Information
     shall be still confidential and the receiving party shall have the same
     care with such Confidential Information and shall have the same protection
     that it generally have with its own Confidential Information (that in any
     case shall not be less than a reasonable care standard) with the objective
     to avoid the disclosure to third parties.

                  (b) As specified in this Agreement, the term Confidential
     Information shall mean any technical or business information provided, in
     any way or mean, or disclosed by Bestel to Maxcom, including without
     limitation to the specifications of products or services, prototypes,
     computing programs, models, drawings, marketing programs, financial data
     and staff statistics. In addition both parties agree and acknowledge that
     this Agreement; including all the terms, conditions and provisions of the
     same, all the drafts, and all the information disclose by any of the
     parties to the other, related to or according to this Agreement comprise
     Confidential Information.

                  (c) All the Confidential Information, unless otherwise
     specified in writing, shall remain as property of the disclosing party, it
     will be used by the receiving party only for the expected purpose, and such
     written Confidential Information, including all the copies of the same,
     shall be returned to the disclosing party or shall be destroyed after the
     need for such Confidential Information has ended. The Confidential
     Information shall not be copied or reproduced unless the need to comply
     with the purpose and intent of this Agreement or in the manner that may be
     required in writing by the disclosing party.

         23.2 The foregoing shall not be applied to the Confidential Information
     that (a) is at disposition of the public from a different mean than through
     the person that receives it; (b) is required to be disclosed by a law,
     order, rule or judicial or governmental regulation; (c) it is independently
     developed by the party releasing such information; (d) becomes available
     for the party that releases such

                                       24

<PAGE>

                                                             English Translation

     information it without restriction of some third parties; or (e) becomes
     related with for the conciliation of any dispute or execution of the any
     party rights according to this Agreement or to the provisions, in that
     event will be taken appropriate protective measurement to keep the
     confidentiality of such Confidential Information as fully as possible,
     within the limits of such conciliation or execution procedure. If it is
     necessary disclose any Confidential Information according to previous
     clause (b), the party that require to do such disclosure must inform
     immediately to the other party about the requirements of such spreading.

         23.3 In spite of the Sections 23.1 and 23.2 any of the parties can
     disclose Confidential Information to its employees, agents or
     representatives and attorneys, financial advisers and accountants and to
     its suppliers related to the negotiation and/or in fulfillment with this
     Agreement or for obtaining financing, provided, however each party shall be
     notified about the confidential and propriety nature of such Confidential
     Information and that the same party is subject to remain compelled by
     similar restrictions on its use and disclosure.

         23.4 The parties agree that any of them can search in different
     entities financings for their projects and/or for the growth of their
     company in general, situation that might force them to reveal certain
     Confidential Information to such financial and/or regulating institutions
     in connection with the searching of such financings. In this event and
     prior to the Confidential Information disclosure the party that discloses
     it must agree with this institution in particular a confidentiality
     agreement, the same that will contain substantially the same restrictions
     of use and disclosure as this Agreement, in order to protect the
     information before being revealed. In such events, the Confidential
     Information shall never exceed: (a) the existence of this and any other
     agreement executed by the parties or (b) the type of product or services
     provided by the parties. Both parties expressly acknowledge that such
     proceedings shall be authorized by the execution of this Agreement.

         23.5 The provisions of this Section 23 shall continue at the
     expiration or termination of this Agreement.

         23.6 Notwithstanding anything to the contrary contained herein, the
     parties acknowledge that this transaction shall be kept confidential until
     the Purchase Price has been paid to Bestel in full.

     24. GENERAL PROVISIONS

         24.1 Modification. This Agreement may not be waived, terminated,
     modified or changed unless by a written consent formalized by the parties.

                                       25

<PAGE>

                                                             English Translation

         24.2 Independent Contractor. The parties hereof are independent
     contractors and nothing herein shall be construed as creating any other
     partnership, agency, joint venture or other relationship between the
     parties. Each party agrees to hold harmless and indemnify the other party
     in connection to any liability initiated against the other party, by its
     employees, agents or representatives, contractors or subcontractors of such
     party.

         24.3 Consent. When a consent or approval of one the parties is
     required, such consent or approval shall not be unreasonably withheld or
     delayed, except if this Agreement stipulates that such party might act at
     its sole discretion in such situation.

         24.4 Waiver. If any of the parties stop insisting on the strict
     fulfillment for the other party of any pact, agreement, term or condition
     hereof or stop exercising any right or remedy, as a consequence to the
     breach of the same, this shall not constitute a waiver of any such breach
     or of such pacts, agreements, terms or conditions. Any waiver of some
     breach will affect or change this Agreement, but each one and all pacts,
     conditions, agreements and terms hereof shall continue in full force and
     effect regarding any other existing or subsequent breach to this Agreement.

         24.5 Copies. This Agreement may be execute in several copies, each copy
     shall be considered as original and all of them together will constitute
     the same instrument.

         24.6 Time Computing. The term in which any act stipulated herein shall
     be executed, shall be calculated excluding the first day and including the
     last one, unless if the last day is a Saturday, Sunday or non-working day,
     and then shall be also excluded.

         24.7 Severability. If a competent court of jurisdiction take for null,
     invalid or non feasible any term, pact, condition or provision hereof, the
     rest provisions will remain in full force and effect and in no way will
     remain affected or invalidated, except that the effect of such invalidity
     or non execution deprive substantially to one of the parties herein of its
     negotiation benefits, according to this Agreement, in that case this will
     be modified in a way to give effect until maximum degree that is possible
     to all rights and obligations of the parties.

         24.8 Lack of Capacity. The parties agrees that the parties shall be
     able to enforce as defense in a legal proceeding the lack of capacity of
     the parties for the execution of this Agreement and the sense that BESTEL
     S.A. de C.V. is referred to as "Bestel" and that MAXCOM TELECOMUNICACIONES
     S.A. de C.V. is referred to as "MAXCOM", given to refer to each one of the
     parties in the above

                                       26

<PAGE>

                                                             English Translation

     mentioned way, implicitly is obtained for transcribed the name of the
     corresponding partnership.

         24.9 Entire Agreement. This Agreement constitute the entire agreement
     and understanding of the parties hereto with respect to the subject matters
     hereof, and supersede all prior agreements, discussions, letters or promise
     of any party, or of its employees, officers or agents of such parties that
     are not contained herein will be compulsory and effective.

         24.10 Registration on the Public Registry. Bestel shall record the acts
     contained herein in any Public Registry that shall be applicable in order
     to safeguard and oppose to thirds the Maxcom rights derived from this
     Agreement.

     FORMALIZED BY THE PARTIES ON THE DATE ABOVE ESTABLISHED.

MAXCOM TELECOMUNICACIONES,              BESTEL, S.A DE C.V.
S.A DE C.V.

BY: /S/ FULVIO DEL VALLE                BY: /S/ IGNACIO DE J. ROMO DAVILA
    /S/ GONZALO ALARCON                    /S/  FRANCISCO XAVIER BASAVE
MR. FULVIO V. DEL VALLE.                MR. IGNACIO DE J. ROMO DAVILA
PRESIDENT AND CEO                       DIRECTOR
MR. GONZALO ALARCON I.                  MR. FRANCISCO XAVIER BASAVE
LEGAL REPRESENTATIVE                    LEGAL REPRESENTATIVE

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                                                  Summarized English Translation

EXHIBIT A. COLLOCATIONS

A.  Exhibit A.1. Collocations Specifications.

Describes the dimensions, security procedures, electricity and other
specifications of the collocation sites.

B.  Exhibit A.2. Collocations Addresses.

Describes the addresses and phone numbers of each collocation site.

C.  Exhibit A.3. Schematic Plans of the Collocations.

Schematic maps of Collocation Rooms for each city described in Exhibit A.2
above.

EXHIBIT B. FIBER OPTIC SPECIFICATIONS.

Describes the specifications of the optic fibers.

EXHIBIT C. NETWORK MAP.

Describes the fiber route across the cities mentioned in Exhibit A.2.

EXHIBIT D. PHYSICAL NETWORK DISTANCES.

Describes the 2,011.55 kilometers of the long distance network across the cities
mentioned in Exhibit A.2.

EXHIBIT E. ACCESS PROTOCOL FOR COLLOCATIONS.

Describes how to use the collocations sites, materials control, personnel access
control, trouble ticket and authorizations.

EXHIBIT F. ACCEPTANCE PROTOCOL FOR THE FIBER SYSTEM.

A.  Exhibit F.1. Acceptance protocol for the collocations.

Test form of collocations.

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<PAGE>

                                                  Summarized English Translation

B. Exhibit F.2. Acceptance protocol for the fibers.

Test form of fibers.

EXHIBIT G. INTERNAL AND OUTSIDE PLANT MAINTENANCE PROCEDURES.

Describes the maintenance plan (preventive and corrective), the time response
and the escalation procedures.

EXHIBIT H. ESCALATION PROCEDURES.

Describes the level of management needed to carry out the repairs and
maintenance of the optic fibers.

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