Document:

<PAGE>
                                                                   Exhibit 10.10

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

                                             UNDER-SECRETARIAT OF COMMUNICATIONS
                                                                      2.- 269/00

                                                       Mexico City, May 30, 2000

MR. RAUL DE JESUS ORTEGA IBARRA
Legal Representative of
Alestra, S de R.L. de C.V.
Av. Paseo de las palmas No. 405 - Piso 21
Col. Lomas de Chapultepec
11000, Mexico D.F.

         The official communication No. 2-268/00 dated May 30, 2000, is formally
delivered herewith, whereby the Secretariat of Communications and Transport
authorizes Alestra, S de R.L. de C.V. to provide local services in Mexico City,
Monterrey N.L. and Guadalajara, Jal., in addition to the ones covered in the
Concession Title to install, operate and develop a public telecommunications
network granted to the company you represent on December 6, 1995, on the terms
set forth in Attachment C, which forms an integral part of the Concession
itself.

         The foregoing is in response to your request dated October 15, 1999,
presented before this Agency of the Federal Government and on the basis of the
favorable opinion issued by the Federal Telecommunications Commission, via
Plenary Agreement No. P/280300/068 dated March 28, 2000.

                                 YOURS SINCERELY
                               THE UNDERSECRETARY

                               Illegible Signature

                                JORGE SILBERSTEIN

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

                                            UNDER-SECRETARIAT OF COMMUNICATIONS
                                                                     2.- 269/00

                                                      Mexico City, May 30, 2000

MR. RAUL DE JESUS ORTEGA IBARRA
Legal Representative of
Alestra, S de R.L. de C.V.
Av. Paseo de las palmas No. 405 - Piso 21
Col. Lomas de Chapultepec
11000, Mexico D.F.

         In reply to your letter dated October 15, 1999, in which you requested
authorization to provide additional services under the Concession Title to
install, operate and develop a public telecommunications network (the
Concession), granted to the company you represent on December 6, 1999, and
taking into account the favorable opinion issued by the Federal
Telecommunications Commission, via Plenary Agreement No. P/280300/068 dated
March 28, 2000; based on article 7 of the Federal Telecommunications Law; 36 of
the Organic Federal Public Administration Law; Condition 1.2 of the Concession,
and 6, Section VIII, of the Interior Regulation of the Secretariat of
Communications and Transport, Alestra, S de R.L. de C.V. (previously Sistemas
Telefonicos de la Republica, S de R.L. de C.V.) is authorized to provide the
local services in Mexico City, Monterrey N.L. and Guadalajara, Jal., in addition
to the ones authorized in the Concession, in compliance with the provisions of
Attachment C, which is affixed hereto and forms an integral part hereof.

                                 YOURS SINCERELY
                               THE UNDERSECRETARY

                               Illegible Signature

                                JORGE SILBERSTEIN

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communicantions and Transport".

Attachment C of the Concession Title for the installation, operation and
exploitation of a public telecommunications network granted by the Federal
Government through the Secretariat of Communications and Transport to Alestra, S
de R.L. de C.V. on December 6, 1995.

C.1. Definition of terms. The terms used in this Attachment shall have the
meaning given to them in the Concession or in the Law, as well as those that are
expressly defined in this section.

        C.1.1 Local service area: this is the geographical area in which the
        Local Service is provided between users located in any point in the
        area, determined in the resolutions issued by the Commission to this
        regard and any that may be issued in the future.

        C.1.2 Commission: the Federal Telecommunications Commission

        C.1.3 Dedicated local link: medium of transmission provided for the
        exclusive use of the user between two specified points located within
        the same local service area.

        C.1.4 Interconnection: physical and logical connection between two
        public telecommunications networks that makes it possible to carry
        public switched traffic between the exchanges of the two networks.
        Interconnection allows the users of one of these networks to connect
        themselves and carry public switched traffic to the users of the other
        network and vice-versa, or to use services provided by the other
        network.

        C.1.5 Interoperability: technical features of the interconnected public
        telecommunications network, through which the provision of a specific
        service is guaranteed in a consistent and predictable manner, in terms
        of the functional delivery of services between networks.

        C.1.6 Basic technical plans: the Basic Signaling Technical Plan and the
        Basic Numbering Technical Plan, published in the Official Gazette of the
        Federation on June 21, 1996, and any others that may be issued by the
        Commission in the future, in compliance with the provisions of article
        41 of the Law and of Rule Thirty-three of the Local Service Rules.

        C.1.7 Rules: the Local Service Rules published in the Official Gazette
        of the Federation on October 23, 1997, or any that may supplement or
        replace them in the future.

        C.1.8 Local service: the service by which public switched traffic is
        carried between users of the same exchange or between users of exchanges
        that form part of the same group of local service exchanges, which do
        not require the dialing of a local prefix to the long distance service,
        regardless of whether or not said public switched traffic is originated
        or terminated in a corded or cordless public telecommunications network
        and for which a rate is charged regardless of the distance.

        The group of local service exchanges referred to in the above paragraph
        should be understood as that which provides the service to the same
        local service area, and

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communicantions and Transport".

        C.1.9 Public switched traffic: any emission, transmission and reception
        of signs, signals, data, letters, images, voice, sound or information of
        any kind that is made through a public telecommunications network using
        both exchanges and numbering assigned and managed by the Commission for
        routing, in compliance with the Basic Numbering Technical Plan.

C.2 Service covered. The following services are covered in this Attachment:

        C.2.1 The local telephone service to residential and business users, in
        compliance with the interconnection and interoperability parameters and
        criteria set forth in the Rules and in this Attachment.

        C.2.2 The emission, transmission or reception of signs, signals,
        letters, images, voice, sound or information of any kind through the
        Network, including non-telephone services such as data, video, audio and
        videoconference.

        C.2.3 The sale or leasing of Network capacity for the emission,
        transmission or reception of signs, signals, letters, images, voice,
        sound or information of any kind.

        C.2.4 The commercialization of the acquired capacity of other public
        telecommunications network concession holders with which the Concession
        Holder has executed the corresponding agreements.

        C.2.5 Operator services authorized for local service concession holders,
        in compliance with the provisions of the Basic Numbering Technical Plan
        and the specific regulation issued to this end by the Commission.

        C.2.6 Provision of local dedicated links, in different formats and
        capacities.

        C.2.7 Value added services whose provision is made possible by the
        licensed public network and which must be registered before the
        Commission prior to their provision, in compliance with the provisions
        of article 33 of the Law, and

        C.2.8 Public telephone services, in compliance with the provisions of
        the Public Telephone Service, published in the Official Gazette of the
        Federation on December 16, 1996.

The services authorized in this Attachment are exhaustive, and therefore any
other service that the Concession holder may seek to provide will require the
respective express concession, permit or authorization of the Secretariat, in
accordance with the provisions of the Law and other applicable provisions.

C.3 Criteria for interconnection with other public telecommunications networks.
In compliance with the provisions of articles 42 and 43 of the Law and Rule
Fifteen and Transitory Rule Nine

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communicantions and Transport".

of the Rules, the Concession holder must negotiate the interconnection
conditions of its Network with any other public telecommunications network
concession holders that request this.

Should the Concession holder fail to agree with another public
telecommunications network concession holder authorized for the provision of the
local service with regard to any of the applicable conditions for the
interconnection of its network, including the respective rates, by the deadline
set forth by law, the Commission shall resolve the matter on the basis of the
following:

     a) The purposes of the Federal Government aimed at increasing the coverage
        and penetration of the telephone service, as well as to improve the
        quality and increase the diversity of services with more accessible
        prices and to the benefit of a greater number of users, and

     b) The services, capabilities or functions provided by the respective
        networks among themselves.

If, for any reason, the interchange of traffic between two networks does not
justify the installation of an interconnection link between the networks
involved, the local transit function may be used.

C.4 The provision of services subject matter hereof. The Concession holder must
comply with the following terms in the provision of the services through its
Network:

        C.4.1 The Concession holder may install user access infrastructure of
        any capacity (broadband, narrowband, E0, NXE0, E1, NXE1, E3 or any other
        standard format) at the request of the users, and may offer the local
        service through said access, along with any of the services covered in
        condition C.2 hereof.

        C.4.2 As from the date on which the Concession holder begins providing
        the local service, it must present before the Commission, within 10
        (ten) working days of the end of each six-month period, a report
        indicating the areas in which it is able to provide said service,
        pointing out any advances made compared to the previous six-month
        period.

        The Concession holder must deal, in a non-discriminatory manner, with
        all requests made in the area in which it is able to provide the local
        service.

        C.4.3 Should the Concession holder attempt to offer the local service
        through any radio-electric spectrum frequency bands that may have been
        licensed to it or that may be licensed to it in the future, it must
        obtain the corresponding authorization from the Secretariat beforehand.

C.5 Provision of dedicated local links. Before the Concession holder grants,
under any legal form, the use of dedicated local links, it must submit the
contract projects for the approval of the Commission and register the respective
rates. A clause must be included in said contracts where both parties agree to
the capacity of the Commission to request any information with regard to

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

the dedicated local links and to verify, on its own account or through an
auditor, the type of traffic carried through the links, as well as the use and
functioning thereof in the installations of users who have contracted services
with the Concession holder. Also, said contract must contemplate causes of
rescission in any cases in which a competent authority determines that one of
the parties is violating a relevant legal, regulatory or administrative
disposition.

C.6 Service of selection by pre-subscription of long distance carrier. In
compliance with the provisions of Rule 12 of the Long Distance Service Rules,
the Concession holder is obliged to install the service of selection by
pre-subscription of long distance carrier in his exchanges.

Notwithstanding the above, the Concession holder shall be exempted from the
obligation of providing its users with the service of selection by
pre-subscription of long distance carrier, until the following conditions have
been met in its corresponding local service area:

     a)   The Concession holder must have been in commercial operation of the
          local service for a period of 5 (five) years, or

     b)   The Concession holder obtains a market share of 25% (twenty-five
          percent) or more.

The conditions set forth above shall not apply to any local service areas in
which the Concession holder has less than 3,000 (three thousand) lines
installed.

Similarly, if the Concession holder provides the users of his local network with
the basic long distance public telephone service, it must offer them rates that
allow the service to be provided on satisfactory conditions of competition.

When, in the opinion of the Commission, the rates referred to in the above
paragraph are substantially different from the ones offered by competing long
distance carriers, such that the Concession holder obtains extraordinary
benefits from the exception to the general criteria referred to in this section,
the Commission shall nullify said exception and the Concession holder shall be
obliged to offer its users the service of selection by pre-subscription of a
long distance carrier.

C.7 Obligation of delivering the telephone number that identifies the call
origin. The Concession holder must comply with the relevant provisions of
section X of article 43 of the Law, as well as with the provisions set forth in
the Basic Signaling Technical Plan. To this end, the Concession holder must send
to the local or long distance service concession holder exchanges to which it
sends switched public traffic, the information specified in said provisions, as
well as information referring to the origin and destination subscriber number.
Because of this, the Concession holder may not reoriginate long distance calls
in order to deliver them as local calls, nor replace or include an "A" number
that does not correspond to the call origin number.

C.8 Exclusive use of interconnection links contracted for traffic reception and
routing. All switched public traffic carried between two local service
concession holders, from one local service concession holder to a long distance
carrier or from one long distance carrier to a local

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

service concession holder must be carried through interconnection links, in
compliance with the corresponding agreements, without modifying the origin and
destination numbers, except in the cases authorized by the Commission.

C.9 Service operation and quality. Until such time as the specific quality
standards for the provision of the local service are issued by the Commission,
the Concession holder must comply with each and every one of the following
minimum standards:

     C.9.1 The percentage of lines with failures must not exceed 4% (four
     percent).

     C.9.2 The percentage of lines repaired the same day on which the complaint
     is received must be at least 80% (eighty percent).

     C.9.3 The percentage of lines repaired within three days of the complaint
     being received must be at least 94% (ninety-four percent).

     C.9.4 The percentage of call attempts during the hour with peak traffic
     receiving the dial tone within 4 (four) seconds, must be at least 99%
     (ninety-nine percent).

     C.9.5 The percentage of local calls set up reaching their destination
     during the hour with peak traffic, without taking into account busy, no
     reply, incomplete dialing or non-existent number conditions, must be at
     least 97% (ninety-seven percent).

     C.9.6 The percentage of operator replies for the directory number
     information services and for receiving complaints shall be at least 92%
     (ninety-two percent).

     C.9.7 The percentage of local dedicated links installed in 20 (twenty)
     days, to which the Concession holder commits is at least 95% (ninety-five
     percent).

     C.9.8 The percentage of local dedicated links installed in 35 (thirty-five)
     days, to which the Concession holder commits is at least 99% (ninety-nine
     percent).

     C.9.9 The percentage of local dedicated links repaired in 8 (eight) hours,
     to which the Concession holder commits is at least 60% (sixty percent).

     C.9.10 The percentage of local dedicated links repaired in one day, to
     which the Concession holder commits is at least 90% (ninety percent).

     C.9.11 The percentage of public telephones out of service shall be no more
     than 12% (twelve percent).

The Concession holder shall, within a period of 90 (ninety) calendar days
counted from the granting of the Concession, present before the Commission for
approval the deadlines by which, in accordance with the technical features of
its Network, it can meet the quality standards for providing the aforementioned
local service. Said deadlines must, under no circumstances, exceed

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

360 (three hundred and sixty) calendar days, counted from the date on which the
provision of the services authorized by this Attachment begins.

Also, each of the above concepts, terms/sections/cases/circumstances must be
reported to the Commission every two months.

C.10 Itemized service provision rates. The measurement, calculation, invoicing,
collection and directory information services provided by the Concession holder
in the interconnection of its public telecommunications network with that of
another local service concession holder, must be provided and charged with
itemized rates that are registered before the Commission and are not
discriminatory with regard to those applied by the Concession holder itelf in
order to carry out similar functions to its subsidiaries and affiliates, to
other service suppliers or to those imputed in separate accounts for the
services it operates.

C.11 Standby for points of interconnection between networks. In compliance with
section II of Rule Twenty-two of the Rules, if the Concession holder operates
more than one exchange within a given local service exchange group (local
service area), it must, following the request of another local service
concession holder, indicate, depending on technical availability, at least a
second point of interconnection between networks for standby purposes.

C.12 Deadline for local service provision. The Concession holder must start to
provide the local service within 360 (three hundred sixty) calendar days of the
issuance of this Attachment.

C.13 Network coverage commitments. The authorized local service areas for the
Concession holder to provide the services covered in this Attachment are those
located in Mexico City, Monterrey, N.L and Guadalajara, Jal.

At the end of the first 2 (two) years following the beginning of local service
provision, the Concession holder must demonstrate to the Commission that it is
using its own or leased infrastructure and is able to provide the local service
to at least 40% (forty percent) of the population of the respective local
service area, according to the latest available census.

At the end of the first 2 (two) years following the beginning of local service
provision, the Concession holder must demonstrate to the Commission that he is
using his own or leased infrastructure and is able to provide the local service
to at least 45% (forty-five percent) of the population of the respective local
service area, according to the latest available census.

The foregoing, is conditioned on the understanding that for both periods, a
substantial proportion (50% or more) of the concession holder's subscribers and
users must be residential.

The Concession holder undertakes to use its own infrastructure to install the
following kilometers of optic fiber ("OF") within the first 5 (five) years as
the issuance of this Attachment:

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------
    Local service area         Year I        Year II      Year III       Year IV       Year V      Total OF
                                                                                                    pair km
---------------------------------------------------------------------------------------------------------------
<S>                              <C>            <C>          <C>           <C>           <C>          <C>
Mexico City                      384            8            458           30            22           902
---------------------------------------------------------------------------------------------------------------
Monterrey, N.L.                   12            4            218           14             8           256
---------------------------------------------------------------------------------------------------------------
Guadalajara, Jal.                 10            2            128           14             6           160
---------------------------------------------------------------------------------------------------------------
Total                            406           14            804           58            36         1,318
---------------------------------------------------------------------------------------------------------------
</TABLE>

The primary transportation network shall contain 18 (eighteen) optic fiber pairs
and the secondary transportation network for customer access shall have 2 (two)
pairs.

The Concession holder shall provide the services authorized in this Attachment,
in compliance with the extension of the Network infrastructure referred to in
Appendix I of Attachment A of the Concession, granted to the Concession holder
on December 17, 1996. Notwithstanding the foregoing, the infrastructure
contemplated in the aforementioned appendix may not be used for the purposes
hereof until such time as the Concession holder starts to provide the local
service.

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------
    Local service area         Year I        Year II      Year III       Year IV       Year V        Total
---------------------------------------------------------------------------------------------------------------
<S>                              <C>           <C>           <C>           <C>           <C>          <C>
Mexico City                      44            14            14            54            35           161
---------------------------------------------------------------------------------------------------------------
Monterrey, N.L.                  26             7             1            28            16            78
---------------------------------------------------------------------------------------------------------------
Guadalajara, Jal.                21             6             0            26             9            62
---------------------------------------------------------------------------------------------------------------
Total                            91            27            15           108            60           301
---------------------------------------------------------------------------------------------------------------
</TABLE>

Similarly, in compliance with the provisions of condition C.4.3 hereof, the
Concession holder shall install during the first 5 (five) years, 9 (nine)
radiobases for point to multipoint microwave digital links, distributed by
stages as follows:

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------
    Local service area         Year I        Year II      Year III       Year IV       Year V      Total OF
                                                                                                    pair km
---------------------------------------------------------------------------------------------------------------
<S>                               <C>           <C>           <C>           <C>          <C>           <C>
Mexico City                       0             0             0             2            2             4
---------------------------------------------------------------------------------------------------------------
Monterrey, N.L.                   0             0             0             1            2             3
---------------------------------------------------------------------------------------------------------------
Guadalajara, Jal.                 0             0             0             0            2             2
---------------------------------------------------------------------------------------------------------------
Total                             0             0             0             3            6             9
---------------------------------------------------------------------------------------------------------------
</TABLE>

In addition to the foregoing, and with regard to the installation of telephone
devices for public usage, the Concession holder undertakes to submit for the
approval of the Commission, within 180 (one hundred eighty) calendar days of the
issuance hereof, the respective public telephone booth installation program.
Once it has been authorized, the program shall have an effective term of 3
(three) years and the Concession holder undertakes to submit the new
installation program for the approval of the Commission 180 (one hundred eighty)
calendar days prior to the end of the effective term of the corresponding
program.

C.14 Attention to requests. The Concession holder undertakes to attend to any
request for telephone service lines in a non-discriminatory manner within a
maximum period of 30 (thirty)

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

calendar days counted from the reception of the corresponding request and to
reduce said period by 5 (five) calendar days each consecutive year until the
year 2004, when the maximum period shall be 10 (ten) calendar days.

C.15 Network installation and maintenance. The Concession holder undertakes to
install and maintain the network in the local service areas referred to herein.
During installation, it undertakes to obtain the relevant permits from the
relevant authorities and to respect any applicable federal, state and municipal
urban development or environmental protection programs.

When the Concession holder builds and installs the Network, it must take public
safety into account, along with the safety of public property and other services
in order to interfere as little as possible with the normal functioning thereof.

C.16 Emergency services. The Concession holder must give priority to the
installation and reparation of the telephone lines of the public security
services, fire fighting units and any other organizations that provide emergency
services and which the Secretariat may specify in accordance with any of its
programs. The Concession holder undertakes to provide any free emergency call
services that the Secretariat may specify within its local service area.

C.17 Directory information and complaints services. The Concession holder must
provide the directory information and complaints services in its local service,
available by dialing the codes set forth for this purpose in the Basic Numbering
Technical Plan 24 (twenty-four) hours a day, every day of the year.

C.18 Noncompliance by the Concession holder. If the Concession holder fails to
comply with its coverage commitments, any quality conditions or any other
condition hereof in one or more local service areas, the Secretariat, in
compliance with the provisions of article 38 of the Law, may nullify the
authorization granted for the provision of services in this local service area
or areas, applying the corresponding surety in such cases.

C.19 Guarantee of Concession holder compliance with its obligations. Without
prejudice to the issuance of general criteria by the Commission, the Concession
holder must provide a surety with an authorized institution in a period not
exceeding 30 (thirty) calendar days counted from the issuance hereof, for the
sum of $11,231,866.00 (ELEVEN MILLION TWO HUNDRED AND THIRTY-ONE THOUSAND EIGHT
HUNDRED AND SIXTY-SIX MEXICAN PESOS 00/100) to the Treasury of the Federation.
Said surety shall guarantee compliance with the infrastructure installation
obligations of the Concession holder, the provision of authorized services and
other obligations arising herefrom, as well as guarantee the payment of any
monetary sanctions imposed by the Secretariat.

Until such time as the aforementioned criteria are defined, the guarantee must
remain in force and be updated yearly in accordance with the National Consumer
Price Index or whichever takes its place.

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

Similarly, the policy in which the surety is issued must contain an express
declaration by which the surety institution accepts the provisions of articles
95 and 166 of the Federal Surety Institutions Law in effect and the waiving of
the order and exclusion benefits.

C:20 Authorization of local service provision contracts. The Concession holder
must submit for the approval of the Commission, following application, the model
contracts to be executed with the users in connection with the provision of the
local service. Similarly, it must present for the authorization of the
Commission any modifications or adjustments to the respective commercial code of
practice.

C.21 Presentation of diverse information. The Concession holder must present, in
a period of 60 (sixty) calendar days counted from the start of local service
provision, for the authorization of the Commission the information corresponding
to the services contemplated herein, regarding the complaints system and failure
reparation and invoicing systems, as well as separate accounts for each service.

C.22 Entry of this Attachment in the Telecommunications Register. The Concession
holder must enter this Attachment in the Telecommunications Register on the
understanding that any Concessions, modifications and attachments that may have
been issued have been entered beforehand.

C.23 Technical network specifications. The Concession holder undertakes to
extend the Network in order to provide telecommunications services in the local
service areas, with at least the technical specifications set forth in section
2.3.1. "Technical Project Specifications" from the request for authorization to
provide the local service, a summary of which is given below:

SUMMARY OF TECHNICAL SPECIFICATIONS OF ATTACHMENT C TO THE CONCESSION TITLE FOR
THE INSTALLATION, OPERATION AND DEVELOPMENT OF A PUBLIC TELECOMMUNICATIONS
NETWORK, GRANTED TO ALESTRA S DE R.L. DE C.V. ON DECEMBER 6, 1995

1. Technical project specifications.

1.1 Switching equipment. Local service switching functions shall be provided by
digital equipment model 5ESS-2000 manufactured by Lucent Technologies or
exchanges with similar capacities and functions, located in the local service
areas covering Mexico City, Monterrey, N.L. and Guadalajara, Jal., using system
and equipment amplitude modulation.

1.2 Transmission equipment (transportation and access). The equipment that will
be used as a transportation medium shall be the metropolitan optic fiber rings,
complemented with microwave digital equipment.

1.3 Customer access equipment. The equipment that will be used for customer
access, in accordance with the particular requirements of each one, may be: (i)
optic fiber connection, (ii)

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

point to point microwave link digital equipment, (iii) point to multipoint
microwave link digital equipment, (iv) copper cable and (v) any other type of
infrastructure leased from third parties.

1.4 Transportation (metropolitan optic fiber rings). The metropolitan optic
fiber rings of the Concession holder are made up as follows:

       .     The first part corresponds to the urban sections of the long
             distance inter-city network (Dense Wave Division Multiplexing
             "DWDM" Transportation Technology) independent of the metropolitan
             networks.

       .     The second part corresponds to the metropolitan ring infrastructure
             (Synchronous Digital Hierarchy "SDH" Transportation Technology)
             that has no relation with the inter-city part of the long distance
             network, and

       .     The third part corresponds to the infrastructure shared between the
             first and second parts (long distance network of 12 "DWDM" pairs
             shared with the local network of 18 "SDH" pairs).

The optic fiber infrastructure shall have the following features:

       .     Three metropolitan rings with SDH technology, using 1,330 nm
             monomode fiber in Mexico City, Monterrey and Guadalajara. These
             networks have protected STM-4 and STM-16 capacity.

       .     The metropolitan rings have 18 pair cable (36 normal dispersion
             index monomode fibers, 1310 and 1550 nm) and two pairs for user
             access.

       .     The urban part of the long distance network has 12 pair cable (24
             fibers and using "DWDM" technology).

1.5 Transportation and access (point to point digital microwave links). If
authorization has been obtained beforehand from the Secretariat for their use in
the Concession holder's own network, the digital microwave access and
transportation equipment shall operate in the 15 GHz and 23 GHz bands, in
compliance with the Concession granted by the Secretariat on June 4, 1998, as
well as any other frequency band in which the Concession holder obtains
frequencies through the respective tenders or leases of the capacity of other
concession holders.

1.6 Point to multipoint digital microwave links. In order to meet low capacity
demand, connectivity solutions may be combined that, along with the supply of
other services, justify the installation of terminal equipment with capacity
ranging from E0 to E1.

With the area of coverage authorized herein, the Concession holder may, with the
necessary authorization, use the 10.5 GHz frequency bands corresponding to the
setting up of point to multipoint digital microwave links, in compliance with
the concession titles granted by the Secretariat on September 28, 1998.

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

2. Technical description of the project and network architecture. The network
architecture for the provision of the local service shall be sufficiently
flexible to quickly incorporate all the services to be supplied in accordance
with the coverage and quality commitments set forth in this resume.

The Concession holder must assign each of its local service exchanges to the
corresponding local service exchange group. A local service exchange may form
part of one or several local service exchange groups. To this end, the
Concession holder must request the authorization of the Commission, which shall
assign the local numbering to be used in the exchange. Said exchange must have
interconnection in all the local service exchange groups of which it forms part.

The Concession holder must offer its users exclusively numbers assigned to the
local service exchange group corresponding to the municipality in which he
provides the service.

The Concession holder shall respect, in all cases in the use of radio-electric
spectrum frequency bands, the geographical limits of the concession on the
radio-electric spectrum frequency bands used to provide the service and use the
local numbering that corresponds to each local service exchange group in
compliance with provisions of the Local Service Rules.

Network Architecture Diagram.

3. Standards and technologies. The equipment, features, standards and protocols
to be used for local service transmission, synchronization, signaling. Microwave
digital links and traffic switching shall be as follows:

3.1 Transmission. The Concession holder's physical transmission network shall
use: (i) in the primary transportation part, the fiber optic metropolitan
infrastructure and microwave digital links and (ii) in the secondary
transportation part (access), optic fiber connections, point to point and point
to multipoint microwave digital links, cordless accesses and copper cabling.

3.2 Equipment in the Points of Presence. The following equipment shall be
available and other equipment may be added that have been officially approved
previously by the Commission:

       . Crossed capacity equipment with capacity ranging from E0 to E1.
       . Crossed capacity equipment with capacity ranging from E1 to STM-1.
       . Electric and optic multiplexor ranging from E1 to STM-4.
       . Electric and optic multiplexor ranging from STM-16 to STM-1.
       . DWDM equipment.
       . Crossed connector-electric/optic multiplexor ranging from E1 to STM-16.
       . Customer access equipment in metropolitan networks.

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

3.3 Optic fiber metropolitan ring capacity

-   Mexico City: STM-16
-   Monterrey: STM-16
-   Guadalajara: STM-4

3.4 Optic fiber metropolitan ring equipping

--------------------------------------------------------------------------------
Equipment                        Alcatel*
--------------------------------------------------------------------------------
Technology                       1330 nm monomode fiber SDH
--------------------------------------------------------------------------------
Protection                       SNCP ring
--------------------------------------------------------------------------------
Add/Drop Capacity                In all nodes
--------------------------------------------------------------------------------
Remote management system         From the Monitoring Center to the Network in
                                 Monterrey
--------------------------------------------------------------------------------

3.5 Synchronization. In accordance with the provisions set forth in the Basic
Signaling Technical Plan, the public telecommunications network shall be
interconnected preferably at E1 level in semi-synchronization, via stratum 1
clocks. The Concession holder supports and upholds UIT recommendations G.703,
G.822 and G.823 in the interconnection points, as well as UIT recommendation
G.812 in the interconnection exchange clocks to avoid the loss of stratum 1
clock reference. Synchronization between the Concession holder network and other
public networks shall be defined by UIT recommendation Q.541.

3.6 Signaling. Until such time as the Secretariat determines other
interconnection architectures, the Concession holder must interconnect with
other public telecommunications networks in two STP pairs (Signaling Transfer
Point) using the quasi-associated signaling mode. Interconnection may use
current signaling systems in the network.

       .  ISUP-MX, NOM-112 for interconnection with Telmex and other carriers.
       .  Exceptionally, R2 for interconnection with exchanges that do not
          support ISUP_MX, NOM-112.
       .  Modified R2 for interconnection between PABX switches and the network.
       .  ETSI-INAP for internal signaling with SCPs.
       .  ISDN Q.931 for access of customers who desire voice and data services
          in the same trunk.

Notwithstanding the foregoing, the Concession holder must, at all times, observe
the basic technical plans necessary for the efficient interconnection and
interoperation between public telecommunications networks, the basic technical
plans drafted and managed by the Commission and any applicable official Mexican
standards.

<PAGE>

In the top left hand corner there is the Mexican coat of arms surrounded by the
words in Spanish "United Mexican States". Under this are the words in Spanish
"Secretariat of Communications and Transport".

3.7 Switching. The main functions of the Concession holder exchanges are:

       .   Call switching
       .   Call control
       .   Subscriber functionalities
       .   Routing logic
       .   Signaling interface
       .   Traffic control
       .   Fraud control
       .   Operation, management and maintenance functions

The sizing of the Exchange capacity and the number of Exchanges required shall
be based on the following criteria:

       .   Market estimates with regard to the number of subscribers
       .   "GOS" grade of service between the Exchange and the public network
       .   Average traffic per subscriber
       .   Call type mixing
       .   Duration time in call reception
       .   Duration time in call transmission.

       -------------------------------------------------------------------------

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                                           SUBSECRETARIA DE COMUNICACIONES

                                           2.-269/00

                                           Mexico, D.F., a 30 de mayo de 2000.

LIC. RAUL DE JESUS ORTEGA IBARRA
Representante Legal de
Alestra, S. de R.L. de C.V.
Av. Paseo de las Palmas No. 405- Piso 21
Col. Lomas de Chapultepec
11000, Mexico, D.F.
P r e s e n t e

     Con el presente se hace entrega formal del oficio No. 2.-268/00 de fecha 30
de mayo de 2000, mediante el cual la Secretaria de Comunicaciones y Transportes
otorga a Alestra, S. de R.L. de C.V., la autorizacion para que preste servicios
locales en las ciudades de Mexico, D.F., Monterrey, N.L. y Guadalajara, Jal.,
adicionales a los comprendidos en el Titulo de Concesion para instalar, operar y
explotar una red publica de telecomunicaciones otorgado a su representada el 6
de diciembre de 1995, en los terminos que se senalan en el Anexo "C", el cual
forma parte integrante de la propia Concesion.

     Lo anterior, en atencion a su solicitud fechada el 15 de octubre de 1999,
presentada ante esta Dependencia del Ejecutivo Federal y en base a la opinion
favorable emitida por la Comision Federal de Telecomunicaciones, mediante
Acuerdo del Pleno No. P/280300/068 de fecha 28 de marzo de 2000.

                                  ATENTAMENTE,
                        SUFRAGIO EFECTIVO. NO REELECCION
                                EL SUBSECRETARIO

                              /s/ Jorge Silberstein
                                JORGE SILBERSTEIN

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                                           SUBSECRETARIA DE COMUNICACIONES

                                           2.-268/00

                                           Mexico, D.F., a 30 de mayo de 2000.

LIC. RAUL DE JESUS ORTEGA IBARRA
Representante Legal de
Alestra, S. de R.L. de C.V.
Av. Paseo de las Palmas No. 405- Piso 21
Col. Lomas de Chapultepec
11000, Mexico, D.F.
P r e s e n t e

En respuesta a su escrito de fecha 15 de octubre de 1999, mediante el cual
solicito autorizacion para prestar servicios adicionales al amparo del Titulo de
Concesion para instalar, operar y explotar una red publica de telecomunicaciones
(la Concesion), otorgado a su representada el 6 de diciembre de 1995, y tomando
en consideracion la opinion favorable emitida por la Comision Federal de
Telecomunicaciones mediante Acuerdo del Pleno No. P/280300/068 de fecha 28 de
marzo de 2000; con fundamento en el articulo 7 de la Ley Federal de
Telecomunicaciones; 36 de la Ley Organica de la Administracion Publica Federal;
Condicion 1.2. de la Concesion, y 6o. fraccion VIII del Reglamento Interior de
la Secretaria de Comunicaciones y Transportes, se autoriza a Alestra, S. de R.L.
de C.V., (antes Sistemas Telefonicos de la Republica, S. de R.L. de C.V.), que
preste en las ciudades de Mexico, D.F., Monterrey, N.L. y Guadalajara, Jal., los
servicios locales, adicionales a los autorizados en la Concesion, conforme a lo
establecido en el Anexo "C" que se adjunta al presente, el cual forma parte
integrante de la misma.

                                  ATENTAMENTE,
                        SUFRAGIO EFECTIVO. NO REELECCION
                                EL SUBSECRETARIO

                         /s/ Jorge Silberstein Tenenbaum
                           JORGE SILBERSTEIN TENENBAUM

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Anexo C del Titulo de Concesion para instalar, operar y explotar una red publica
de telecomunicaciones otorgado por el Gobierno Federal, por conducto de la
Secretaria de Comunicaciones y Transportes, en favor de Alestra S. de R.L. de
C.V., con fecha 6 de diciembre de 1995.

C.1. DEFINICION DE TERMINOS. Los terminos empleados en el presente Anexo tendran
el significado que se les de en la Concesion o en la Ley, asi como los que sean
expresamente definidos en este numeral.

        C.1.1. Area de servicio local: es la delimitacion geografica en la cual
        se presta el Servicio Local entre usuarios ubicados en cualquier punto
        dentro de ella, determinada en las resoluciones emitidas por la Comision
        al respecto y las que en el futuro se emitan;

        C.1.2. Comision: la Comision Federal de Telecomunicaciones;

        C.1.3. Enlace dedicado local: medio de transmision provisto para uso
        exclusivo del usuario entre dos puntos definidos y ubicados dentro de
        una misma Area de servicio local;

        C.1.4. Interconexion: conexion fisica y logica entre dos redes publicas
        de telecomunicaciones, que permite cursar trafico publico conmutado
        entre las centrales de ambas redes. La interconexion permite a los
        usuarios de una de las redes, conectarse y cursar trafico publico
        conmutado a los usuarios de la otra y viceversa, o utilizar servicios
        proporcionados por la otra red;

        C.1.5. Interoperabilidad: caracteristicas tecnicas de las redes publicas
        de telecomunicaciones interconectadas, por medio de las cuales se
        asegura la provision de un servicio especifico de una manera consistente
        y predecible, en terminos de la entrega funcional de servicios entre
        redes;

        C.1.6. Planes tecnicos fundamentales: el Plan Tecnico Fundamental de
        Senalizacion y el Plan Tecnico Fundamental de Numeracion, publicados en
        el Diario Oficial de la Federacion el 21 de junio de 1996, y los que en
        lo sucesivo emita la Comision, de conformidad con lo establecido en el
        articulo 41 de la Ley y en la Regla Trigesimatercera de las Reglas del
        Servicio Local;

        C.1.7. Reglas: las Reglas del Servicio Local, publicadas en el Diario
        Oficial de la Federacion el 23 de octubre de 1997, o las que en lo
        sucesivo las complementen o sustituyan;

        C.1.8. Servicio local: aquel por el que se conduce trafico publico
        conmutado entre usuarios de una misma central o entre usuarios de
        centrales que forman parte de un mismo grupo de centrales de servicio
        local, que no requiere de la marcacion de un prefijo de acceso al
        servicio de larga distancia, independientemente de que dicho trafico
        publico conmutado se origine o termine en una red publica de
        telecomunicaciones alambrica o inalambrica, y por el que se cobra una
        tarifa independiente de la distancia;

        El grupo de centrales de servicio local a que se refiere el parrafo
        anterior, debe de entenderse como aquellas que proporcionan el servicio
        en una misma Area de servicio local, y

        C.1.9. Trafico publico conmutado: toda emision, transmision o recepcion
        de signos, senales, datos, escritos, imagenes, voz, sonidos o
        informacion de cualquier naturaleza que se efectue a traves de una red
        publica de telecomunicaciones que utilice para su enrutamiento tanto
        centrales como numeracion asignada y administrada por la Comision, de
        conformidad con el Plan Tecnico Fundamental de Numeracion.

                                        1

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C.2. SERVICIOS COMPRENDIDOS. En el presente Anexo, se encuentran comprendidos
los siguientes servicios:

        C.2.1. El servicio de telefonia local a usuarios residenciales y
        comerciales, de conformidad con los parametros y criterios de
        interconexion e interoperabilidad que se establecen en las Reglas y en
        el presente Anexo;

        C.2.2. La emision, transmision o recepcion de signos, senales, escritos,
        imagenes, voz, sonidos o informacion de cualquier naturaleza a traves de
        su Red, incluyendo servicios no telefonicos como datos, video, audio y
        videoconferencia;

        C.2.3. La venta o arrendamiento de capacidad de la Red para la emision,
        transmision o recepcion de signos, senales, escritos, imagenes, voz,
        sonidos o informacion de cualquier naturaleza;

        C.2.4. La comercializacion de la capacidad adquirida de otros
        concesionarios de redes publicas de telecomunicaciones con las que el
        Concesionario tenga celebrados los convenios correspondientes;

        C.2.5. Servicios de operadora autorizados a los concesionarios del
        Servicio local, de conformidad con lo establecido en el Plan Tecnico
        Fundamental de Numeracion y la regulacion especifica que al efecto emita
        la Comision;

        C.2.6. Provision de enlaces dedicados locales, en los diversos formatos
        y capacidades;

        C.2.7. Servicios de valor agregado que le permita prestar la red publica
        concesionada, mismos que debera registrar ante la Comision previamente a
        su prestacion, de conformidad con lo dispuesto en el articulo 33 de la
        Ley, y

        C.2.8. Servicios de telefonia publica, de conformidad con lo establecido
        en el Reglamento del Servicio de Telefonia Publica, publicado en el
        Diario Oficial de la Federacion el 16 de diciembre de 1996.

Los servicios autorizados en el presente Anexo se deben entender
limitativamente; por lo tanto, cualquier otro servicio que el Concesionario
pretenda proporcionar, requerira de la respectiva concesion, permiso o
autorizacion expresa de la Secretaria, de acuerdo a lo establecido por la Ley y
demas disposiciones aplicables.

C.3. CRITERIOS PARA LA INTERCONEXION CON OTRAS REDES PUBLICAS DE
TELECOMUNICACIONES. De conformidad con lo establecido por los articulos 42 y 43
de la Ley y las Reglas Decimaquinta y NOVENA TRANSITORIA de las Reglas, el
Concesionario debera negociar las condiciones de interconexion de su Red con las
de otros concesionarios de redes publicas de telecomunicaciones que se lo
soliciten.

                                        2

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En el supuesto de que el Concesionario no convenga con otro concesionario de red
publica de telecomunicaciones autorizado para la prestacion del Servicio local,
cualesquiera de las condiciones aplicables a la interconexion de sus redes
incluyendo las tarifas respectivas, dentro del plazo establecido por la Ley, la
Comision resolvera considerando fundamentalmente lo siguiente:

        a) Los objetivos del Gobierno Federal tendientes al incremento de la
           cobertura y penetracion del servicio telefonico, asi como a elevar la
           calidad y aumentar la diversidad de los servicios con precios mas
           accesibles y en beneficio de un mayor numero de usuarios, y

        b) Los servicios, capacidades o funciones que se provean las respectivas
           redes entre si.

Cuando por cualquier motivo el intercambio de trafico entre dos redes no
justifique la instalacion de un enlace de interconexion entre las redes
involucradas, se podra utilizar la funcion de transito local.

C.4. PRESTACION DE LOS SERVICIOS OBJETO DEL PRESENTE ANEXO. En la prestacion de
los servicios mediante su Red, el Concesionario debera ajustarse a lo siguiente:

        C.4.1. El Concesionario podra instalar infraestructura de acceso a los
        usuarios de cualquier capacidad (banda angosta, banda ancha, E0, NXE0,
        E1, NXE1, E3 o cualquier otro formato estandar existente) a solicitud de
        los mismos y podra ofrecer por dicho acceso el Servicio local, asi como
        cualquiera de los servicios comprendidos en la condicion C.2. del
        presente Anexo.

        C.4.2. A partir de la fecha en que el Concesionario inicie la prestacion
        del Servicio local, debera presentar ante la Comision, dentro de los
        primeros 10 (diez) dias habiles posteriores a que concluya cada
        semestre, un informe en el que senale las demarcaciones en las que se
        encuentra en posibilidad de prestar dicho servicio, senalando los
        avances respecto al semestre anterior.

        El Concesionario debera atender de manera no discriminatoria toda
        solicitud dentro del area en la que se encuentra en posibilidad de
        prestar el Servicio local.

        C.4.3. En caso de que el Concesionario pretenda ofrecer el Servicio
        local a traves de bandas de frecuencias del espectro radioelectrico que
        le hubieren sido concesionadas o le sean concesionadas en el futuro,
        debera obtener previamente la autorizacion correspondiente de la
        Secretaria.

                                        3

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C.5. PROVISION DE ENLACES DEDICADOS LOCALES. De manera previa a que el
Concesionario otorgue, bajo cualquier figura juridica, el uso de enlaces
dedicados locales, debera someter a la aprobacion de la Comision los proyectos
de contratos y registrar las tarifas respectivas. En dichos contratos se debera
incorporar una clausula en la que ambas partes acuerden la facultad de la
Comision de requerir cualquier informacion respecto a los enlaces dedicados
locales y la de verificar, por si misma o por conducto de un auditor, el tipo de
trafico cursado a traves de los enlaces, asi como el uso y funcionamiento de los
mismos en las instalaciones de los usuarios que hayan contratado con el
Concesionario. Asimismo, dicho contrato debera contemplar causales de rescision
en los casos en que alguna autoridad competente determine que alguna de las
partes infringe alguna disposicion legal, reglamentaria o administrativa
aplicable.

C.6. SERVICIO DE SELECCION POR PRESUSCRIPCION DEL OPERADOR DE LARGA DISTANCIA.
De conformidad con lo establecido en la Regla 12 de las Reglas del Servicio de
Larga Distancia, el Concesionario tiene la obligacion de implantar en sus
centrales el servicio de seleccion por presuscripcion del operador de larga
distancia.

No obstante lo anterior, el Concesionario estara exento de la obligacion de
proporcionar a sus usuarios el servicio de seleccion por presuscripcion del
operador de larga distancia, hasta que se cumpla, en el Area de servicio local
correspondiente, cualquiera de las siguientes condiciones:

     a)   Que el Concesionario haya estado en operacion comercial del Servicio
          local, durante un periodo de 5 (cinco) anos; o

     b)   Que el Concesionario logre una participacion de mercado del 25%
          (veinticinco por ciento) o mas.

Las condiciones establecidas en los incisos anteriores, no seran aplicables para
aquellas Areas de servicio local en las que el Concesionario tenga menos de
3,000 (tres mil) lineas instaladas.

De igual forma, en el caso en que el Concesionario preste a los usuarios de su
red local el servicio publico de telefonia basica de larga distancia, debera
ofrecerles tarifas que permitan la prestacion del servicio en condiciones
satisfactorias de competencia.

Cuando a juicio de la Comision las tarifas a que se refiere el parrafo que
antecede sean significativamente diferentes a las que ofrecen en competencia las
empresas de larga distancia, de forma que el Concesionario obtenga beneficios
extraordinarios de los criterios generales de excepcion a los que se refiere el
presente numeral, la Comision dejara sin efectos la presente excepcion y el
Concesionario estara obligado a ofrecer a sus usuarios el servicio de seleccion
por presuscripcion del operador de larga distancia.

                                        4

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C.7. OBLIGACION DE ENTREGA DEL NUMERO TELEFONICO QUE IDENTIFICA EL ORIGEN DE LA
LLAMADA. El Concesionario debera cumplir con lo aplicable de lo dispuesto en la
fraccion X del articulo 43 de la Ley, asi como en las disposiciones establecidas
en el Plan Tecnico Fundamental de Senalizacion. Al efecto, el Concesionario
debera enviar a las centrales del concesionario de servicio local o de larga
distancia al que entregue el Trafico publico conmutado, la informacion que se
estipula en dichas disposiciones, asi como la informacion referente al numero
del abonado de origen y de destino. Por lo anterior, el Concesionario no podra
reoriginar llamadas de larga distancia para entregarlas como locales, ni
substituir o incorporar un numero de "A" que no corresponda al numero de origen
de la llamada.

C.8. USO EXCLUSIVO DE LOS ENLACES DE INTERCONEXION CONTRATADOS PARA LA RECEPCION
Y ENRUTAMIENTO DEL TRAFICO. Todo Trafico publico conmutado que se curse entre
dos concesionarios de servicio local, de un concesionario de servicio local a un
operador de larga distancia o de un operador de larga distancia a un
concesionario de servicio local, debera conducirse a traves de enlaces de
interconexion ajustandose a los convenios correspondientes, sin modificar los
numeros de origen o de destino, salvo en aquellos casos autorizados por la
Comision.

C.9. OPERACION Y CALIDAD DE LOS SERVICIOS. Hasta en tanto no sean emitidas por
la Comision las normas de calidad especificas para la prestacion del Servicio
local, el Concesionario debera cumplir con todas y cada una de las normas
minimas que a continuacion se refieren:

        C.9.1. El porcentaje de lineas con falla respecto al total de lineas en
        servicio debera ser como maximo del 4% (cuatro por ciento);

        C.9.2. El porcentaje de reparacion de lineas el mismo dia de recepcion
        de la queja debe ser como minimo del 80% (ochenta por ciento);

        C.9.3. El porcentaje de reparacion de lineas dentro de los tres dias
        siguientes al de la recepcion de la queja, sera como minimo del 94%
        (noventa y cuatro por ciento);

        C.9.4. El porcentaje de intentos de llamadas en la hora de maximo
        trafico que recibe el tono de marcar en 4 (cuatro) segundos, debera ser
        al menos de 99% (noventa y nueve por ciento);

        C.9.5. El porcentaje de establecimiento de llamadas locales que lleguen
        a su destino en la hora de maximo trafico, sin considerar si esta
        ocupado, no contesta el numero deseado, marcacion incompleta o numero
        inexistente, debera ser como minimo del 97% (noventa y siete por
        ciento);

        C.9.6. El porcentaje de contestacion de operadora para los servicios de
        informacion de numeros de directorio y para recepcion de quejas sera
        como minimo del 92% (noventa y dos por ciento);

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        C.9.7. El porcentaje de instalacion de enlaces dedicados locales en 20
        (veinte) dias a que se obliga como minimo el Concesionario es de 95%
        (noventa y cinco por ciento);

        C.9.8. El porcentaje de instalacion de enlaces dedicados locales en 35
        (treinta y cinco) dias a que se obliga como minimo el Concesionario es
        de 99% (noventa y nueve por ciento);

        C.9.9. El porcentaje de reparacion de enlaces dedicados locales en 8
        (ocho) horas a que se obliga como minimo el Concesionario es de 60%
        (sesenta por ciento);

        C.9.10. El porcentaje de reparacion de enlaces dedicados locales en un
        dia a que se obliga como minimo el Concesionario es de 90% (noventa por
        ciento), y

        C.9.11. El porcentaje de telefonos publicos fuera de servicio sera del
        12% (doce por ciento) como maximo;

En un plazo de 90 (noventa) dias naturales contados a partir del otorgamiento de
la Concesion, el Concesionario presentara a la aprobacion de la Comision los
plazos en que, de acuerdo con las caracteristicas tecnicas de su Red, pueda
cumplir con las normas de calidad para la prestacion del Servicio local antes
senaladas. Dichos plazos no deberan exceder, en ningun caso, de 360 (trescientos
sesenta) dias naturales, contados a partir del inicio de la prestacion de los
servicios autorizados mediante el presente Anexo.

De igual forma, cada uno de los anteriores conceptos deberan ser reportados a la
Comision de manera bimestral.

C.10. TARIFAS DESAGREGADAS EN LA PRESTACION DE LOS SERVICIOS. Los servicios de
medicion, tasacion, facturacion, cobranza y servicios de informacion de
directorio que provea el Concesionario en la interconexion de su red publica de
telecomunicaciones con la de otro concesionario de servicio local, deberan
prestarse mediante el cobro de tarifas desagregadas registradas ante la
Comision, que no resulten discriminatorias respecto de aquellas que el propio
Concesionario aplique por llevar a cabo funciones similares a sus subsidiarias y
filiales, a otros proveedores de servicio o a las que impute en la contabilidad
separada por servicios a su propia operacion.

C.11. RESPALDO DE LOS PUNTOS DE INTERCONEXION ENTRE REDES. De conformidad con la
fraccion II de la Regla Vigesimasegunda de las Reglas, si el Concesionario opera
mas de una central dentro de un grupo de centrales de servicio local determinado
(Area de servicio local), debera, previa solicitud de otro concesionario de
servicio local, senalar, sujeto a factibilidad tecnica, al menos un segundo
punto de interconexion en sus centrales, con proposito de respaldo.

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C.12. PLAZO PARA INICIAR LA PRESTACION DEL SERVICIO LOCAL. El Concesionario
debera iniciar la prestacion del Servicio local, a mas tardar, en los siguientes
360 (trescientos sesenta) dias naturales, contados a partir del otorgamiento del
presente Anexo.

C.13. COMPROMISOS DE COBERTURA DE LA RED. Las areas de servicio local
autorizadas para que el Concesionario proporcione los servicios comprendidos en
el presente Anexo, son aquellas donde se encuentran ubicadas las ciudades de
Mexico, D.F., Monterrey, N.L. y Guadalajara, Jal.

Al termino de los primeros 2 (dos) anos posteriores al inicio de la prestacion
del Servicio local, el Concesionario debera acreditar ante la Comision que con
infraestructura propia o arrendada, esta en posibilidad de prestar el Servicio
local a cuando menos el 40% (cuarenta por ciento) de la poblacion del Area de
servicio local respectiva conforme al ultimo censo disponible.

Para el termino de los 5 (cinco) anos contados a partir de la fecha de inicio de
la prestacion del Servicio local, el Concesionario debera acreditar ante la
Comision que con infraestructura propia o arrendada, esta en posibilidad de
prestar el Servicio local a cuando menos el 45% (cuarenta y cinco por ciento) de
la poblacion del Area de servicio local respectiva conforme al ultimo censo
disponible.

Lo anterior, en el entendido que para ambos terminos, un porcentaje
significativo (50% o mas) de sus suscriptores y usuarios deben ser
residenciales.

El Concesionario se obliga a instalar con infraestructura propia, en los
primeros 5 (anos) contados a partir del otorgamiento del presente Anexo, los
siguientes kilometros de fibra optica ("FO"):

   ------------------------------------------------------------------------
   AREA DE SERVICIO                                                TOTAL DE
         LOCAL         ANO I   ANO II   ANO III  ANO IV   ANO V     KMS. DE
                                                                   PARES DE
                                                                      FO
   ------------------------------------------------------------------------
   Mexico, D.F.         384      8        458      30       22         902
   ------------------------------------------------------------------------
   Monterrey, N.L.       12      4        218      14        8         256
   ------------------------------------------------------------------------
   Guadalajara, Jal.     10      2        128      14        6         160
   ------------------------------------------------------------------------
   Total                406     14        804      58       36       1,318
   ------------------------------------------------------------------------

La red de transporte principal contendra 18 (dieciocho) pares de fibra optica y
la red de transporte secundaria para acceso con los clientes, 2 (dos) pares.

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El Concesionario prestara los servicios autorizados en el presente Anexo, de
conformidad con la ampliacion de la infraestructura de la Red a que se hace
referencia en el Apendice I del Anexo A de la Concesion, otorgado en favor del
Concesionario el 17 de diciembre de 1996. No obstante lo anterior, la
infraestructura contemplada en el apendice anteriormente mencionado no podra
utilizarse para efectos del presente Anexo, hasta en tanto el Concesionario no
inicie la prestacion del Servicio local.

El Concesionario, observando previamente lo dispuesto en la condicion C.4.3. del
presente Anexo, debera instalar durante los primeros 5 (cinco) anos, 301
(trescientos uno) enlaces digitales de microondas punto a punto, distribuidos
por etapas de la siguiente forma:

   ----------------------------------------------------------------------
     AREA DE SERVICIO    ANO I  ANO II   ANO III  ANO IV   ANO V    TOTAL
          LOCAL
   ----------------------------------------------------------------------
   Mexico, D.F.           44      14       14       54      35       161
   ----------------------------------------------------------------------
   Monterrey, N.L.        26       7        1       28      16        78
   ----------------------------------------------------------------------
   Guadalajara, Jal.      21       6        0       26       9        62
   ----------------------------------------------------------------------
   Total                  91      27       15      108      60       301
   ----------------------------------------------------------------------

De igual forma, de conformidad con lo dispuesto por la condicion C.4.3. del
presente Anexo, el Concesionario instalara durante los primeros 5 (cinco) anos,
9 (nueve) radiobases para enlaces digitales de microondas punto a multipunto,
distribuidas por etapas de la siguiente forma:

   ----------------------------------------------------------------------
     AREA DE SERVICIO    ANO I  ANO II   ANO III  ANO IV   ANO V    TOTAL
          LOCAL
   ----------------------------------------------------------------------
   Mexico, D.F.            0       0        0        2       2        4
   ----------------------------------------------------------------------
   Monterrey, N.L.         0       0        0        1       2        3
   ----------------------------------------------------------------------
   Guadalajara, Jal.       0       0        0        0       2        2
   ----------------------------------------------------------------------
   Total                   0       0        0        3       6        9
   ----------------------------------------------------------------------

En adicion a lo anterior, respecto al programa de instalacion de aparatos
telefonicos de uso publico, el Concesionario se obliga a someter a la aprobacion
de la Secretaria o la Comision,

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dentro de los 180 (ciento ochenta) dias naturales siguientes al otorgamiento del
presente Anexo, el programa de instalacion de casetas publicas telefonicas
respectivo. Una vez autorizado, el programa tendra una vigencia de 3 (tres) anos
y el Concesionario se obliga a someter a la aprobacion de la Secretaria o la
Comision el nuevo programa de instalacion con 180 (ciento ochenta) dias
naturales de anticipacion a que termine la vigencia del programa
correspondiente.

C.14. ATENCION DE SOLICITUDES. El Concesionario se obliga a atender cualquier
solicitud de lineas de servicio telefonico de manera no discriminatoria, en un
plazo maximo de 30 (treinta) dias naturales, contados a partir de que reciba la
solicitud correspondiente y a disminuir en 5 (cinco) dias naturales el plazo
maximo mencionado por cada ano sucesivo hasta el ano 2004, en el que el plazo
maximo sera de 10 (diez) dias naturales.

C.15. INSTALACION Y MANTENIMIENTO DE LA RED. El Concesionario se obliga a
instalar y mantener la red en las areas de servicio local a que se refiere este
Anexo. En la instalacion de esta, se obliga a conseguir los permisos relativos
ante las autoridades competentes y a respetar los programas federales, estatales
y municipales de desarrollo urbano y de proteccion ecologica aplicables.

Cuando el Concesionario construya e instale la Red, debera tomar en cuenta la
seguridad del publico, de sus bienes y de otros servicios, a efecto de
interferir lo menos posible con su funcionamiento normal.

C.16. SERVICIOS DE EMERGENCIA. El Concesionario debera dar prioridad a la
instalacion y reparacion de las lineas telefonicas de los cuerpos de seguridad
publica, bomberos y organizaciones que presten servicios de emergencia y que la
Secretaria determine conforme a los programas que establezca. El Concesionario
se obliga a proporcionar gratuitamente los servicios de llamadas de emergencia
que determine la Secretaria dentro de su Area de servicio local.

C.17. SERVICIOS DE INFORMACION DE DIRECTORIO Y DE RECEPCION DE QUEJAS. El
Concesionario debera proporcionar servicios de informacion de directorio y de
recepcion de quejas del Servicio local, a traves de la marcacion de los codigos
asignados en el Plan Tecnico Fundamental de Numeracion para este proposito,
durante las 24 (veinticuatro) horas del dia, todos los dias del ano.

C.18. INCUMPLIMIENTO DEL CONCESIONARIO. Si en una o mas areas de servicio local
el Concesionario incumple con los compromisos de cobertura, cualquiera de las
condiciones de calidad o cualquier otra condicion del presente Anexo, la
Secretaria, conforme lo dispuesto por el articulo 38 de la Ley, podra dejar sin
efectos la autorizacion otorgada para prestar servicios en esa o esas areas de
servicio local, aplicando en tales casos, la fianza correspondiente.

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C.19. GARANTIA DEL CUMPLIMIENTO DE LAS OBLIGACIONES DEL CONCESIONARIO. Sin
perjuicio de que la Comision establezca criterios de aplicacion general, el
Concesionario debera establecer fianza con institucion autorizada, en un plazo
no mayor de 30 (treinta) dias naturales contados a partir del otorgamiento del
presente Anexo, por la cantidad de $11' 231,866.00 (ONCE MILLONES DOSCIENTOS
TREINTA Y UN MIL OCHOCIENTOS SESENTA Y SEIS PESOS 00/100 M.N.), a favor de la
Tesoreria de la Federacion. Dicha fianza garantizara el cumplimiento de las
obligaciones de instalacion de infraestructura del Concesionario, prestacion de
los servicios autorizados y demas obligaciones derivadas del presente Anexo, asi
como para garantizar el pago de las sanciones pecuniarias que, en su caso,
imponga la Secretaria.

En tanto no se definan los criterios generales senalados con anterioridad, la
garantia debera mantenerse vigente y actualizarse anualmente conforme al Indice
Nacional de Precios al Consumidor o el Indice que los sustituya.

De igual forma, la poliza en que se expida la fianza debera contener la
declaracion expresa de que la institucion afianzadora acepta lo establecido en
los articulos 95 y 118 de la Ley Federal de Instituciones de Fianzas en vigor y
la renuncia a los beneficios de orden y excusion.

C.20. AUTORIZACION DE LOS CONTRATOS DE PRESTACION DEL SERVICIO LOCAL. El
Concesionario debera someter a la aprobacion de la Comision, previamente a su
aplicacion, los modelos de contratos a ser celebrados con los usuarios
relacionados con la prestacion del Servicio local. Asimismo, debera presentar
para la autorizacion de la Comision las modificaciones o adecuaciones al codigo
de practicas comerciales respectivo.

C.21. PRESENTACION DE INFORMACION DIVERSA. En un plazo de 60 (sesenta) dias
naturales contados a partir del inicio de la prestacion del Servicio local, el
Concesionario debera presentar para la autorizacion de la Comision la
informacion correspondiente de los servicios contemplados en el presente Anexo,
relativa al sistema de quejas y reparacion de fallas y sistemas de facturacion,
asi como la relativa a la separacion contable por servicio.

C.22. INSCRIPCION DEL PRESENTE ANEXO EN EL REGISTRO DE TELECOMUNICACIONES. El
Concesionario debera inscribir el presente Anexo ante el Registro de
Telecomunicaciones, en el entendido de que previamente deberan estar inscritos
la Concesion, las modificaciones y los anexos que, en su caso, se hubieren
otorgado.

C.23. ESPECIFICACIONES TECNICAS DE LA RED. El Concesionario se obliga a ampliar
la Red para proporcionar los servicios de telecomunicaciones en las areas de
servicio local, cuando menos con las especificaciones tecnicas indicadas en el
numeral 2.3.1. "Especificaciones tecnicas, del proyecto", de su solicitud de
autorizacion para prestar el Servicio local, del cual un resumen se transcribe a
continuacion:

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RESUMEN DE ESPECIFICACIONES TECNICAS DEL ANEXO C DEL TITULO DE CONCESION PARA
INSTALAR, OPERAR Y EXPLOTAR UNA RED PUBLICA DE TELECOMUNICACIONES, OTORGADO EN
FAVOR DE ALESTRA, S. DE R.L. DE C.V. EL 6 DE DICIEMBRE DE 1995.

1.      ESPECIFICACIONES TECNICAS DEL PROYECTO.

1.1.    Equipos de conmutacion. Las funciones de conmutacion del Servicio Local
seran realizadas por centrales digitales modelo 5ESS-2000, fabricadas por Lucent
Technologies o centrales con capacidades y-funciones similares, ubicadas en las
Areas de servicio local donde se encuentran comprendidas las ciudades de Mexico,
D.F., Monterrey, N.L. y Guadalajara, Jal., mediante ampliaciones modulares de
sistemas y equipos.

1.2.    Equipos de transmision (transporte y acceso). Los equipos que se
utilizaran como medio de transporte seran los anillos metropolitanos de fibra
optica, complementados con equipo digital de microondas.

1.3     Equipos de acceso al cliente. El equipo que se utilizara para el acceso
al cliente, de acuerdo a los requerimientos particulares de cada uno, podra ser:
(i) acometida de fibra optica, (ii) equipo digital de enlaces de microondas
punto a punto, (iii) equipo digital de enlaces de microondas punto a multipunto,
(iv) cable de cobre y (v) cualquier otro tipo de infraestructura arrendada a
terceros.

1.4     Transporte (anillos metropolitanos de fibra optica). Los anillos
metropolitanos de fibra optica del Concesionario se componen de la siguiente
manera:

..   La primera parte corresponde a los tramos urbanos de la red interurbana de
    larga distancia (Tecnologia de Transporte Dense Wave Division Multiplexing
    "DWDM"), independiente a las redes metropolitanas.

..   La segunda parte corresponde a la infraestructura de los anillos
    metropolitanos (Tecnologia de Transporte Synchronous Digital Hierarchy
    "SDH"), que no tiene relacion con la parte interurbana de la red de larga
    distancia, y.

..   La tercera parte corresponde a la infraestructura compartida por la primera
    y la segunda (red de larga distancia de 12 pares "DWDM" compartida con red
    local de 18 pares "SDH").

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LA INFRAESTRUCTURA DE FIBRA OPTICA TENDRA LAS SIGUIENTES CARACTERISTICAS:

..   Tres anillos metropolitanos con tecnologia SDH, usa fibra monomodo de 1,330
    nm en las ciudades de Mexico, Monterrey y Guadalajara; estas redes tienen
    capacidad de STM-16 y STM-4 protegidos.

..   Los anillos metropolitanos tienen cable de 18 pares (36 fibras monomodo de
    indice de dispersion normal, 1310 y 1550nm) y dos pares para acceso al
    usuario.

..   La parte urbana de la red de larga distancia tiene cable de 12 pares (24
    fibras e incorpora la tecnologia "DWDM").

1.5     Transporte y acceso (enlaces de microondas digitales punto a punto). En
caso de obtener previamente de la Secretaria la autorizacion para su uso en su
propia red, los equipos de transporte y acceso de microondas digitales operaran
en las bandas de 15 GHz y 23 GHz, de conformidad con la Concesion otorgada por
la Secretaria el 4 de junio de 1998, asi como cualquier otra banda de
frecuencias en la que el Concesionario obtenga frecuencias por medio de las
licitaciones respectivas o arriende capacidad de otros concesionarios.

1.6     Enlaces de microondas digitales punto a multipunto: Para satisfacer la
demanda de baja capacidad, se podran combinar soluciones de conectividad que,
junto con la oferta de otros servicios, justifiquen la instalacion de equipos
terminales con capacidad desde un E0 hasta un E1.

Dentro del area de cobertura autorizada en el presente Anexo, el Concesionario
podra, previa autorizacion, utilizar las bandas de frecuencias de 10.5 GHz
correspondientes al establecimiento de enlaces de microondas de punto a
multipunto, de conformidad con los titulos de concesion otorgados por la
Secretaria el dia 28 de septiembre de 1998.

2.      DESCRIPCION TECNICA DEL PROYECTO Y DE LA ARQUITECTURA DE LA RED. La
arquitectura de red para la prestacion del Servicio Local sera lo
suficientemente flexible para incorporar rapidamente todos los servicios que se
pretenden ofrecer de acuerdo con los compromisos de cobertura y calidad
estipulados en el presente resumen.

El Concesionario debera asignar cada una de sus centrales de servicio local al
grupo de centrales de servicio local que le corresponda, una central de servicio
local podra formar parte de uno o varios grupos de centrales de servicio local.
Al efecto, el Concesionario debera solicitar autorizacion a la Comision, quien
asignara la numeracion local que se

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utilizara en la central. Dicha central debera tener interconexion en todos los
grupos de centrales de servicio local de los que forme parte.

El Concesionario debera ofrecer a sus usuarios exclusivamente numeros asignados
al grupo de centrales de servicio local correspondiente a la poblacion en donde
les presta el servicio.

En el uso de bandas de frecuencias del espectro radioelectrico para la
prestacion del Servicio Local, el Concesionario respetara, en todo caso, los
limites geograficos de las concesiones sobre bandas de frecuencias del espectro
radioelectrico que utilice para prestar el servicio y utilizar la numeracion
local que corresponda a cada grupo de centrales de servicio local de conformidad
con las disposiciones contenidas en las Reglas del Servicio Local.

                      DIAGRAMA DE LA ARQUITECTURA DE LA RED

[GRAPHIC APPEARS HERE]

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3.      ESTANDARES Y TECNOLOGIAS. Los equipos, facilidades, estandares y
protocolos que seran utilizados para la transmision, sincronizacion,
senalizacion, enlaces digitales de microondas y conmutacion del trafico de
servicio local seran los siguientes.

3.1.    Transmision. La red fisica de transmision propia utilizara: (i) en la
parte de transporte principal, la infraestructura metropolitana de fibra optica
y enlaces digitales de microondas y (ii) en la parte de transporte secundario
(acceso), acometidas de fibra optica, enlaces digitales de microondas punto a
punto, punto a multipunto, accesos inalambricos y cableado de cobre.

3.2.    Equipos en los Puntos de Presencia. Se contara con los siguientes
equipos y se podran adicionar otros que previamente hayan sido homologados por
la Comision:

..   Equipo de conexion cruzada con capacidad de E0 a E1
..   Equipo de conexion cruzada con capacidad de E1 a STM-1
..   Multiplexor electrico y optico de E1 a STM-4
..   Multiplexor electrico y optico de STM-16 a STM-1
..   Equipo de DWDM
..   Conector cruzado-multiplexor electrico/optico de E1 a STM-16
..   Equipo para acceso a clientes en redes metropolitanas

3.3.    Capacidad de los anillos metropolitanos de fibra optica:

    .   Mexico: STM-16,
    .   Monterrey: STM-16
    .   Guadalajara: STM-4.

3.4.    Equipamiento de los anillos metropolitanos de fibra optica

--------------------------------------------------------------------------------
Equipo:                     Alcatel*
--------------------------------------------------------------------------------
Tecnologia:                 SDH de fibra monomodo de 1330 nm
--------------------------------------------------------------------------------
Proteccion:                 Anillo SNCP
--------------------------------------------------------------------------------
Capacidad de Add/Drop:      En todos los nodos
--------------------------------------------------------------------------------
Sistema de gestion remota:  Desde el Centro de Monitoreo de la Red en Monterrey,
                            N.L.
--------------------------------------------------------------------------------

* El Concesionario podra emplear cualquier otro equipo previamente homologado.

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3.5.    Sincronizacion. De acuerdo con las disposiciones establecidas en el Plan
Tecnico Fundamental de Senalizacion, las redes publicas de telecomunicaciones
estaran interconectadas preferentemente a nivel de E1 en modo plesiocrono, a
traves de relojes de estrato 1. El Concesionario apoya y soporta las
recomendaciones G.703, G.822 y G.823 de la UIT en los puntos de interconexion,
asi como la recomendacion G.812 de la UIT en los relojes de las centrales de
interconexion para evitar perdida de referencia del reloj de estrato 1. La
sincronizacion entre la red del Concesionario y otras redes publicas estara
definida por la recomendacion Q.541 de la UIT.

3.6.    Senalizacion. En tanto la Secretaria no determine otras arquitecturas de
interconexion, el Concesionario debera interconectarse con otras redes publicas
de telecomunicaciones en dos pares de STP (Punto de Transferencia de
Senalizacion) utilizando el modo de senalizacion cuasi-asociado. La
interconexion podra emplear sistemas de senalizacion existentes en la Red.

..   ISUP-MX, NOM-112 para la interconexion con Telmex y otros operadores.
..   Por excepcion, R2 para la interconexion con centrales que no soportan
    ISUP-MX, NOM112.
..   R2 modificado para la interconexion entre conmutadores PABX y la Red.
..   ETSI-INAP para la senalizacion intema con los SCPs.
..   ISDN Q.931 para los accesos de clientes que deseen servicios de voz y datos
    en una misma troncal.

No obstante lo anterior, el Concesionario debera observar en todo momento, los
planes tecnicos fundamentales necesarios para la eficiente interconexion e
interoperabilidad entre redes publicas de telecomunicaciones, los planes
tecnicos fundamentales elaborados y administrados por la Comision, asi como las
normas oficiales mexicanas que resulten aplicables.

3.7.    Conmutacion. Las principales funciones de las centrales del
Concesionario son:

..   Conmutacion de llamadas.
..   Control de llamadas.
..   Funcionalidades de abonado.
..   Logica de enrutamiento.
..   Interfaz de senalizacion.
..   Control de trafico.
..   Control de fraude.
..   Funciones de operacion, administracion y mantenimiento.

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El dimensionamiento de la capacidad de la Central y el numero de Centrales
requeridas estara basado en los siguientes criterios:

..   Estimados de mercado con respecto al numero de abonados.
..   Grado de servicio "GOS" entre la Central y la red publica.
..   Trafico promedio por abonado.
..   Mezcla de tipos de llamadas.
..   Tiempo de duracion en la recepcion de la llamada.
..   Tiempo de duracion en el envio de la llamada.

                                       16<PAGE>

                                                                   EXHIBIT 4.3.1

                            AMENDED ESCROW AGREEMENT

     This Escrow Agreement is made this 13th day of January, 2003, by and
between Oregon Trail Ethanol Coalition, L.L.C., a Nebraska limited liability
company ("OTEC"), U.S. Bancorp Piper Jaffray, Inc. ("Underwriter") and Midwest
Bank N.A., a Nebraska chartered banking corporation, with an office located in
Deshler, Nebraska ("Escrow Agent").

                                    RECITALS:

     WHEREAS, OTEC was formed for the purpose of constructing and operating an
ethanol plant near Davenport, in Thayer County, Nebraska;

     WHEREAS, OTEC is, or will be, conducting a public offering of its
membership units and pursuant to the terms and conditions of its prospectus,
OTEC has committed to escrow the proceeds of the membership units sold to
investors;

     WHEREAS, OTEC has retained the services of Underwriter to assist with the
sale of the membership units on a best efforts basis.

     WHEREAS, OTEC and Underwriter have agreed to provide for the impoundment of
the proceeds to be received from the sale of the membership units.

     WHEREAS, OTEC and Underwriter wish to establish an escrow account with
Midwest Bank, N.A. to hold the proceeds of subscriptions for the membership
units for a minimum of 18,000 membership units and a maximum of 24,000
membership units, until written instructions from OTEC have been received;

     WHEREAS, Midwest Bank N.A. is willing to hold the escrow account and serve
as Escrow Agent, in accordance with the terms and conditions provided in this
Escrow Agreement.

     NOW, THEREFORE, the parties agree as follows:

     1.   Establishment of Escrow Account. OTEC shall open and maintain an
escrow account with Escrow Agent which shall be an interest bearing account, and
shall earn interest at the rate offered from time to time by Escrow Agent (the
"Escrow Account").

     2.   Escrow Account Authorizations. Only officers of the Escrow Agent shall
be entitled to withdraw funds from the Escrow Account as provided herein. OTEC
shall deliver to Escrow Agent for deposit in the Escrow Account all funds,
checks, bank money orders, etc., received by OTEC from the sale of membership
units. All checks, bank money orders, etc. shall be made payable to "Midwest
Bank N.A. as Escrow Agent for Oregon Trail Ethanol Coalition, L.L.C.". OTEC
shall deliver to Escrow Agent with each subscriber's funds, the subscriber's
name, address, amount of investment and date of deposit. Escrow Agent shall
maintain this information in its records for the purpose of returning to each
subscriber the subscriber's funds in the event that the minimum equity offering
of $18 million is not subscribed by March 1, 2003, subject to extension by
OTEC to up to April 30, 2003, the OTEC prospectus (the "Termination Date"). All
proceeds so deposited shall remain the property of the subscriber and shall not
be subject to any liens or charges by the Escrow Agent or judgments or
creditors' claims against OTEC unless and until released to OTEC as hereinafter
provided. The pro rata amount of interest to be allocated to each subscriber in
the event the funds are returned to the subscribers will be based on the date of
the deposit of the respective subscriber's funds into the Escrow Account by
OTEC.

<PAGE>

     3.   Investment of Deposited Funds. The Escrow Agent shall invest all funds
received and deposited in the Escrow Account in United States government or
government agency securities, or certificates of deposit issued by banks with a
net worth of at least $18,000,000. Any investment of deposited funds must be
made in recognition that offering proceeds must be able to be transmitted
promptly to OTEC or the subscribers if the stated conditions are met. The
following securities are not permissible as investments: (1) money market funds;
(2) corporate equity or debt securities; (3) repurchase agreements; (4) bankers
acceptances; (5) commercial paper; and (6) municipal securities.

     4.   Withdrawals from Escrow Account.

          (a)  Disbursement Of 10% Of Escrow Funds. If the Escrow Agent
receives, on or before the Termination Date, subscriptions in an aggregate
amount of not less than $18,000,000 and written acceptance of each subscriber's
subscription by OTEC, and OTEC has met the Release Conditions set forth in
Paragraph 4(c) below, then the Escrow Agent shall disburse, upon written
instruction from OTEC, substantially in the form attached hereto as Exhibit A,
10% of the subscription payments held in the Escrow Account to OTEC ("Initial
Disbursement"). If the Escrow Agent receives additional subscription payments
after the Initial Disbursement, the Escrow Agent shall deposit the subscription
payments into the Escrow Account and upon receiving written instruction from
OTEC, substantially in the form attached hereto as Exhibit A, shall disburse to
OTEC 10% of all subscription payments received after the Initial Disbursement.
The Escrow Agent shall retain the remaining 90% of all subscription payments in
the Escrow Account to be disbursed as set forth in Section 4(b) below.

          (b)  Disbursement Of Remaining 90% Of Subscription Payments. Upon
receipt by the Escrow Agent of written confirmation from OTEC that OTEC has
received an executed commitment letter from a lender for the amount of debt
financing that OTEC determines necessary ("Commitment Letter Notice"), and OTEC
has met the Release Conditions set forth in Paragraph 4(c) below, the Escrow
Agent shall disburse to OTEC, pursuant to written instruction from OTEC,
substantially in the form attached hereto as Exhibit A, the remaining 90% of the
subscription payments remaining in the Escrow Account in immediately available
funds ("90% Disbursement"). If the Escrow Agent receives additional subscription
payments after the 90% Disbursement, then the Escrow Agent shall disburse the
subscription payments to OTEC upon written instruction from OTEC, substantially
in the form attached hereto as Exhibit A. If the Escrow Agent does not receive
the Commitment Letter Notice from OTEC by the Termination Date, then the Escrow
Agent shall refund to subscribers with interest determined on a pro rata basis
per subscriber, the remaining 90% of each Subscriber's subscription payment per
written instruction from OTEC.

          (c)  Conditions on Disbursements. OTEC shall not withdrawal funds from
the Escrow Account under Paragraph 4(a) or Paragraph 4(b) above for use by OTEC
unless the following conditions are met (the "Release Conditions"): (a) there
shall not be any legal orders prohibiting the offering or release of funds from
escrow, or orders from the United States Securities and Exchange Commission
revoking the effectiveness of the Registration Statement related to the
offering, and (b) the Escrow Agent has contacted the Securities Bureau of the
Nebraska Department of Banking and Finance (the "Bureau") and the Bureau has
indicated that the funds may be released from the Escrow Account.

     5.   Termination of Escrow Account. In the event that OTEC has not received
subscriptions for the minimum offering amount by the Termination Date, then OTEC
shall instruct the Escrow Agent to return to the subscribers, all funds from the
sale of membership units held in the Escrow Account with interest determined on
a pro rata basis per subscriber.

                                        2

<PAGE>

OTEC may, in its sole discretion, abandon the sale of the membership units at
any time prior to the termination of the offering period. Upon the receipt of
written instructions from the Chairman of the Board or President of OTEC that
the offering is being abandoned, the Escrow Agent shall refund the monies on
deposit to the subscribers thereof as provided in this Paragraph 5.

     6.   Escrow Agent's Reliance. Escrow Agent shall be under no duty or
responsibility to make any inquiry or investigation as to the accuracy,
adequacy, and shall be entitled to assume conclusively, correctness and
completeness of any and all information given in any affidavit, statement, or
other paper received by Escrow Agent under this Escrow Agreement, including, but
not limited to the prospectus. Escrow Agent shall be entitled to rely upon any
notice, request, affidavit, approval, statement, consent or other paper believed
by Escrow Agent to be genuine and to have been signed by the proper party or
parties.

     7.   Hold Harmless. Escrow Agent shall not be liable to OTEC and/or any
subscriber for any error of judgment, or for any act done or step taken or
omitted by it in good faith, or for any mistake of fact or law, or for anything
which it may do or refrain from doing in connection herewith, excepting only its
own intentional and deliberate misconduct.

     8.   Indemnification. OTEC agrees to defend, indemnify and hold Escrow
Agent harmless from and against any and all claims, actions, judgments, losses,
liabilities, obligations, damages, charges, costs, and expenses of any nature
whatsoever, including, without limitation, reasonable attorneys' fees and
expenses incurred by Escrow Agent (including such fees and expenses incurred in
any litigation by or against any of the parties to this Escrow Agreement under
this Paragraph 8, arising directly or indirectly from, out of or incident to
this Escrow Agreement, excepting only those accruing as a result of Escrow
Agent's own intentional and deliberate misconduct).

     9.   Escrow Agent's Fees. Escrow Agent shall be entitled to charge OTEC a
fee for providing services hereunder in accordance with the terms of Exhibit B
attached hereto and incorporated herein by reference.

     10.  Time. Time is of the essence of this Agreement.

     11.  Applicable Law. The interpretation and enforcement of this Agreement
shall be governed by the laws of the State of Nebraska.

     12.  Binding Effect. This Agreement shall be binding upon the parties and
their respective successors and assigns.

     IN WITNESS WHEREOF, the parties have hereunto signed this Agreement.

OREGON TRAIL ETHANOL COALITION, L.L.C.       MIDWEST BANK, N.A.,
a Nebraska limited liability company         a Nebraska chartered banking
                                             corporation

By:      /s/ Mark Jagels                     By:      /s/ Rob Schardt
   -----------------------------------          --------------------------------

   Its:  Chairman of the Board                  Its:  President
       -------------------------------              ----------------------------

U.S. BANCORP PIPER JAFFRAY, INC.

By:      /s/ Mark E. Fisler
   -----------------------------------
   Its:  Managing Director
       -------------------------------

                                        3

<PAGE>

                                    EXHIBIT A

                         FUND DISBURSEMENT INSTRUCTIONS

The undersigned certifies that he, she or it is duly authorized to execute and
deliver this Escrow Notice on behalf of Oregon Trail Ethanol Coalition, L.L.C.
("OTEC"). Pursuant to the Amended Escrow Agreement dated January 13, 2003 (the
"Escrow Agreement") by and among OTEC U.S. Bancorp Piper Jaffray, Inc.
("Underwriter") and Midwest Bank, N.A. (the "Escrow Agent"), OTEC hereby request
that the Escrow Agent remit, in immediately available funds, $_____________ from
the Escrow Account to the following parties as follows:

                  PARTY                          AMOUNT
                  -----                          ------

                                                 $

                                     TOTAL       $

IN WITNESS WHEREOF, the undersigned have executed this Fund Disbursement
Instruction as of the date set forth below.

OREGON TRAIL ETHANOL COALITION, L.L.C.
a Nebraska limited liability company

By:
   --------------------------------------------------

   Its:   Chairman of the Board
       ----------------------------------

                                        4

<PAGE>

                                    EXHIBIT B

                                  FEE AGREEMENT

     Regardless of whether the Release Conditions are met by the Termination
Date the Escrow Agent shall be paid a fee of $500 plus the aggregate of the
Daily Escrow Charges (as defined below) for each day funds are held in the
Escrow Account . The "Daily Escrow Charge" shall equal the balance of the funds
held in the Escrow Account on each day multiplied by .005 and then divided by
365.

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