Exhibit 10.15.1

Amended and Restated
AT&T Master Carrier Agreement

|                                            
|--------------------------------------------
|CUSTOMER Name (Full Legal Name):            
|Universal Access                            
|("CUST0MER")                                
|                                            
|CUSTOMER Name (and Title) for Notice:       
|                                            
|CUSTOMER Address:233 S. Wacker Dr. Suite 600
|                                            
|CityChicago                                 
|                                            
|CUSTOMER Fax number for Notice:312-660-5057 
|                                            

CUSTOMER
and AT&T entered into a Master Carrier Agreement executed by the parties on the following dates:

|Date of execution by CUSTOMER: |  |  |  | Date of execution by AT&T: |  | 
|------------------------------ |  |  |  | -------------------------- |  | 

The
parties hereby replace that prior agreement with this Amended and Restated Master Carrier Agreement, which shall be legally binding when signed by both parties and shall continue in effect until
the end of the longest term specified in the Attachment(s), or until otherwise terminated as provided in accordance with this Agreement. The rates and commitments provided in the Attachments shall be
effective as provided in each Attachment.

This
Amended and Restated Master Carrier Agreement consists of this Cover Sheet, the attached Terms and Conditions, and the Attachment(s) listed below (these documents together are collectively
referred to as the "Agreement"). In the event of any inconsistency between these documents, precedence will be given to the documents in the following order: (1) this Cover Sheet;
(2) Attachment(s); (3) the Terms and Conditions. In the event of any inconsistency between the terms of this Agreement and the terms of an applicable Tariff, the terms of the Agreement
shall prevail.

|Title                                                             |  | Doc. ID                 |  | Date/time stamp   
|----------------------------------------------------------------- |  | ----------------------- |  | ------------------
|Master Carrier Agreement Terms and Conditions                     |  | MCA990816.doc           |  | 08/16/99 3:42 pm  
|Data Service Terms and Pricing                                    |  | UAI DSTP010413          |  | 04/13/01 10:20 AM 
|Local ServicesDedicated Transport Services                       |  | UAI DTSSTP001031        |  | 10/31/2000 2:38 PM
|AT&T Term Plan-Service Order Attachment                           |  | ma-vii-termplan-sig.doc |  | 07/3l/2001        
|AT&T Teleconference Services Pricing Plan                         |  | TC123.45                |  |                   
|AT&T Teleconference Web Meeting Services Service Order Attachment |  | AWM SOA 022602.doc      |  |                   

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CUSTOMER'S SIGNATURE BELOW ACKNOWLEDGES THAT CUSTOMER HAS READ, UNDERSTANDS AND AGREES TO EACH OF THE TERMS AND CONDITIONS OF THIS AGREEMENT AND THAT THE INDIVIDUAL SIGNING
THIS AGREEMENT IS DULY AUTHORIZED TO DO SO.

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|CUSTOMER |                                                                           | AT&T Corp.
|-------- | ------------------------------------------------------------------------- | ----------
|         |                                                                           |           
|By:      | /s/GEORGE A. KING(Authorized Customer Signature)                          |           
|         | George A. King,Chief Development Officer(Typed or Printed Name and Title) |           
|Date:    | June 20, 2002                                                             |           

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AT&T MA Reference No.

AT&T Term Plan - Service Order Attachment

|CUSTOMER Legal Name ("Customer", "You or Your")                                                                     |  | AT&T Corp. ("AT&T")                               |  | AT&T Sales Contact Name                                                                                                                         
|------------------------------------------------------------------------------------------------------------------- |  | ------------------------------------------------- |  | ------------------------------------------------------------------------------------------------------------------------------------------------
|Universal Access, Inc.                                                                                              |  | AT&T Corp.                                        |  | Robert Gartner                                                                                                                                  
|Customer Address                                                                                                    |  | AT&T Address                                      |  | AT&T Sales Contact Address                                                                                                                      
|233 S. Wacker Dr. Suite 600
Chicago
Il                        USA
60606                                             |  | 55 Corporate Drive
Bridgewater, New Jersey 08807  |  | 1701 Golf Road Tower 3 Floor 5
Rolling Meadows
IL                        USA
60008                                                              
|Customer Contact                                                                                                    |  | AT&T Contact                                      |  | AT&T Sales Contact Information                                                                                                                  
|Name: Jim Nettleton
Title: Director
Telephone: 312-660-3648
Fax: 312-881-4066
Email: jnettleton@universalaccess.net |  | Master Agreement Support Team
Email: mast@att.com |  | Telephone: 847-952-2507
Fax: 847-952-2622
Email: robertgartner@att.com
Branch Manager: Pat Griffin
Sales Strata: Wholesale Sales Region: Western
|Customer Billing Address                                                                                            |  | Customer Account Information                      |  |                                                                                                                                                 
|233 S. Wacker Dr. Suite 600
Chicago
IL                        USA
60606                                             |  | Master Customer Number (MCN): 319100
Plan ID No.  |  |                                                                                                                                                 

This Service Order Attachment is an Attachment to the Master Agreement between Customer and AT&T
dated                        , ("Agreement") is an
integral part of that Agreement. Services provided under the Term Plan selected below are subject to the rates and terms and conditions as described in the AT&T Business Service Guide located at
http:/lwww.att.com/serviceguide/business. The order of priority in the event of inconsistency among terms shall be the Attachment, then the Master Agreement, and then the AT&T Business Service Guide
at http/Iwww.att.com/serviceguide/business.

Eligible Charges:If you have selected an AT&T Term Plan which includes a revenue or usage
commitment, the commitment will be satisfied by the charges for AT&T Services as described In the AT&T Service Guide.

Term Start Date:The Term start date will be determined by AT&T in accordance with the type and
availability of Services, provisioning requirements, local access, and site readiness.

Contract Prices:Your Term Plan prices, Including discounts, credits and waivers, are specified in
the AT&T Service Guide. Upon expiration of the Term, Services will continue to be provided under the terms of the Agreement, until terminated at any time by either party on notice to the other, at the
charges specified In the AT&T Service Guide.

Shortfall Charges:If you have selected an AT&T Term Plan which Includes a revenue or usage
commitment and If You fail to satisfy Your commitment, You will be billed a shortfall charge. The shortfall charge will be calculated as set forth in description of Your Term Plan In the AT&T Service
Guide.

Termination Charges:Subject to certain exceptions, if Your Term Plan is terminated before the end of
the Term, You will be billed Termination Charges calculated as set forth in description of Your Term Plan in the AT&T Service Guide. Customer hereby places an order for an AT&T Term Plan as follows:

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AT&T Term Plan

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SIGNATURE BELOW BY YOUR AUTHORIZED REPRESENTATIVE IS YOUR CONSENT TO
THE TERMS AND CONDITIONS OF THIS SERVICE ORDER ATTACHMENT.

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|CUSTOMER: Insert Customer's Legal Name |                                         | AT&T CORP.
|---------------------------------------- | --------------------------------------- | ----------
|                                         |                                         |           
|By:                                      | /s/GEORGE A. KING(Authorized Signature) |           
|                                         | George A. King(Typed or Printed Name)   |           
|                                         | Chief Development Officer(Title)        |           
|                                         | June 20, 2002(Date)                     |           

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AT&T MA Reference #

AT&T Teleconference Web Meeting Services Service Order Attachment

|CUSTOMER Legal Name                                                                                                 |  | AT&T Corp. ("AT&T")                                                                          |  | AT&T Sales Contact Name                                                                                                                
|------------------------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------------------------------------------- |  | ---------------------------------------------------------------------------------------------------------------------------------------
|Universal Access, Inc.                                                                                              |  | AT&T Corp.                                                                                   |  | Robert Gartner                                                                                                                         
|CUSTOMER Address                                                                                                    |  | AT&T Address                                                                                 |  | AT&T Sales Contact Address                                                                                                             
|233 S. Wacker Dr. Suite 600
Chicago
IL                        USA
60606                                             |  | 55 Corporate Drive
Bridgewater, New Jersey 08807                                             |  | 1701 Golf Road Tower 3 Floor 5
Rolling Meadows
IL                        USA
60008                                                     
|CUSTOMER Contact                                                                                                    |  | AT&T Contact                                                                                 |  | AT&T Sales Contact Information                                                                                                         
|Name: Jim Nettleton
Title: Director
Telephone: 312-660-3648
Fax: 312-881-4066
Email: jnettleton@universalaccess.net |  | Master Agreement Support Team
Email:mast@att.comurl:http://ma.kweb.att.com/Fax: 908-658-2562 |  | Telephone: 847-952-2507
Fax: 847-952-2622
Email:robertgartner@att.comBranch Manager: Pat Griffin
Sales Strata: Wholesale Territory #: 0
|CUSTOMER Billing Address                                                                                            |  | CUSTOMER Account Information                                                                 |  |                                                                                                                                        
|233 S. Wacker Dr. Suite 600
Chicago
IL                        USA
60606                                             |  | Master Customer Number (MCN): 319100
Plan ID Number                                          |  | o AT&T SDN OneNet®o AT&T VTNS®o AT&T ABN®o AT&T UniPlan®                                                                               

This
Service Order Attachment for the AT&T Teleconference Web Meeting Services ("Service") consists of a Terms and Conditions Section and a Pricing Schedule, which together constitute an
Attachment to the Master Agreement dated between You and AT&T ("Agreement") and is an integral part of that Agreement. In the event of conflict among the documents, the order of priority shall be this
Attachment, then the Master Agreement General Terms and Conditions.

This
Attachment is effective when signed by both You and AT&T (the "Effective Date').

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CUSTOMER HAS READ AND UNDERSTANDS THE TERMS AND CONDITIONS OF THIS
SERVICE ORDER ATTACHMENT AND AGREES TO BE BOUND BY THEM.

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|CUSTOMER: Universal Access, Inc. |                                         | AT&T CORP.
|-------------------------------- | --------------------------------------- | ----------
|                                 |                                         |           
|By:                              | /s/GEORGE A. KING(Authorized Signature) |           
|                                 | George A. King(Typed or Printed Name)   |           
|                                 | Chief Development Officer(Title)        |           
|                                 | June 20, 2002(Date)                     |           

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Terms And Conditions

Section 1.    Scope and Service Description

This service is a Data Conference Service ("AT&T WebMeeting Service") that must be established as a Service within the family of AT&T TeleConference Services.
AT&T WebMeeting Service can be used in conjunction with other AT&T TeleConference Services to enable Customers to present, collaborate, share files/applications and modify documents via the Internet.
Specific Web Meeting Services Feature Descriptions are as set forth in Section 2 herein.

2.    Feature Description

The following primary features are currently available for this service, as may be modified from time to time:



AT&T
reserves the right to modify features from time to time. Consult your AT&T Sales Representative for updates on feature modifications and enhancements.

3.    Charges

AT&T reserves the right to modify charges for AT&T Web Meeting Service. Should AT&T elect to modify rates, AT&T and Customer will attempt to negotiate a revised
Web Meeting Service Order Attachment, which reflects the new Web Meeting Service rate, based on mutual agreement. Notwithstanding, anything contained herein to the contrary if Customer and AT&T are
unable to reach

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agreement on a modified rate for Web Meeting Services, AT&T will have no further obligation to provide service at the rates contained in this Attachment.

Charges
for AT&T Web Meeting Service are in addition to applicable charges for other AT&T TeleConference Service, which can be used in conjunction with Web Meeting Service. If
teleconference charges retire an AT&T minimum annual revenue commitment, then AT&T WebMeeting Service usage charges will contribute toward retirement of a minimum revenue commitment in any
TeleConference
specific Term Plan, TeleConference Service Order Attachment, in an AT&T Service Order Attachment, or other agreements.

There
are two, billing options available; details are as set forth in Section 6 herein.

4.    Term

There is no term associated with this attachment.

5.    Payment

Charges are billed and payable in U.S. Dollars.

6.    Web Meeting Service Rates and Charges

There are two WebMeeting Service billing options: Cost Per Minute or Seat License billing. A checked box below indicates the agreed option:

Schedule I
    ý Cost Per Minute

Web Meeting usage charges are $.33 cents per minute multiplied by the number of ports used in a WebMeetlng conference to determine the total usage minutes. Total
usage minutes are calculated for each WebMeeting conference. Charges for AT&T Web Meeting Service are in addition to applicable charges for AT&T TeleConference Service, which can be used in
conjunction with Web Meeting Service.

If
CUSTOMER utilizes the Multliocation Billing option from AT&T TeleConference Services, all locations are affected by this WebMeeting billing option. WebMeeting Cost Per Minute charges
can appear at applicable specific locatIon(s).

A
No Show fee will apply if zero ports are used after 30 minutes from the reserved start time of a WebMeeting. The fee is calculated by multiplying the cost per minute rate by the amount
of ports by 30 minutes.

Schedule II
    o Seat License

Web Meeting usage charges are based on a calendar month subscription to Seat Licenses. Seat Licenses equate to concurrent CUSTOMER ports in use at any time and
provide unlimited usage to less than or equal to the total amount of Seat Licenses subscribed to for all concurrent WebMeeting conferences. Seats are available to all CUSTOMER users. The Web Meeting
charges are $         per Seat. CUSTOMER must subscribe to a minimum of             Seats. Initially, CUSTOMER will subscribe
to            Seats. CUSTOMER's monthly Seat
License rate equates to the amount of subscribed Seats multiplied by the amount per Seat.

If
concurrent CUSTOMER users exceed the amount of Seat Licenses, $1.00 per minute for each port in excess of the current amount of Seats subscribed to for the duration each
excessive port is used until total users equate to or are less than the amount of seats subscribed to.

CUSTOMER
changes to the amount of subscribed Seats must be provided with 15 days written notice to your AT&T TeleConference Account Executive. While the amount of Seats subscribed to can
increase or decrease, CUSTOMER cannot subscribe to less than the minimum number of Seats.

If
CUSTOMER utilizes Multilocation Billing option from AT&T TeleConference Services, all locations are affected by this WebMeeting billing option. All locations can use WebMeeting Seat
Licenses and all locations will contribute to the amount of concurrent users but all WebMeeting charges and credits are billed to the Headquarters location.

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AT&T TELECONFERENCE SERVICES PRICING PLAN  Attachment to AT&T Term Plan

AT&T TeleConference Service Description

The AT&T TeleConference Service is comprised of several elements. The primary elements include The AT&T Corporate Plan and Executive Offerings. Other elements may
be selected and attached as a separate service order attachments. These other elements may include: Web Meeting, Global Offer, and Conference Casting. Usage from these elements will count toward the
overall commitment.

For
detailed information on 'availability, please refer to the AT&T Business Service Guide at http://www.att.com/serviceguide /business.

RATES: Corporate Plan & Executive Offerings

All Rates are per minute per person/connection unless otherwise specified. Rates for Operator Dialed & Toll Free Dial-In include bridge + transport. Rates
for Caller Paid Dial-In include the bridge charges only. Participants pay own transport.



Call Option

Bridge

Transport

TotalOperator Dialed

$
0.200

$
0.060

$
0.260Operator Assisted Toll Free Dial-In

$
0.130

$
0.060

$
0.190Automated Toll Free Dial-In

$
0.100

$
.0600

$
0.160Reservationless Toll Free Dial-In

$
0.100

$
0.600

$
0.160Operator Assisted Caller Paid Dial-In

$
0.130

$
.*

$
0.130Automated Caller Paid Dial-In

$
0.100

$
.*

$
0.l00Reservationless Caller Paid Dial-In

$
0.100

$
.*

$
0.100


International.    Includes
Bridge Charge plus International transport

Canada:    $0.65/minute/connection
weekdays;
$0.48/minute/connection weekends**.

Other
International:    Charges to the U. S. from the international calling location apply and will be billed by the participant's carrier.

Call Cancellation/No-Show Charges



Executive Offerings

AT&T TeleConference Service provides three (3) levels of service - Executive, Premier, and Event.



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Call Option

Executive

Premier

EventOperator Dialed

$
0.550

$
0.550

$
0.550Operator Assisted Toll Free Dial-In*

$
0.550

$
0.550

$
0.550Automated Toll Free Dial-In

$
0.450

$
0.350

$
0.350Operator Assisted Caller Paid Dial-In *

$
0.400

$
0.300

$
0.300Automated Caller Paid Dial-In*

$
0.300

$
0.300

$
0.300




International

Operator-Dialed:$0.450 (Bridge Rate Only) plus applicable AT&T Business International Long Distance rates.

Canada: $0.65/minute/connection
weekdays; $0.48/minute/connection weekends**.

Other
International: Charges to the U. S. from the international calling location apply and will be billed by the participant's carrier.

Call Cancellation/No-Show Charges

Executive Offerings$5.00/unused reserved Dial-In connection unless: 24-hour advance cancellation notice for calls with
less than 1,000 connections; 48-hour advance cancellation notice for calls with 1,000 or more connections. A minimum charge of $3,375.00 per TeleConference applies only to teleconferences of
1,000 reserved connection or more if not canceled 48-hours or more before the call start time.

OPTIONAL FEATURE CHARGES FOR CORPORATE AND EXECUTIVE OFFERINGS

Optional Features

For detailed information on feature availability, please refer to the AT&T Business Service Guide at http://www.att.com/serviceguide/business.



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EXECUTIVE & PREMIER BILLABLE FEATURES

|                                                                               
|-------------------------------------------------------------------------------
|
|                                                                               
|Communications Line                                                            
|                                                                               
|Participant Screening                                                          
|                                                                               
|Participant List                                                               
|                                                                               
|Moderator Led Q & A                                                            
|                                                                               
|Voting & Polling                                                               
|                                                                               
|Sub-conferencing                                                               
|                                                                               
|Other Options                                                                  
|                                                                               
|Tape Recording $20.per hour                                                    
|                                                                               
|Digitized Replay
$.40lminute for TF; $.35 minute for Caller Paid               
|                                                                               
|Transcription: $50 per transcription increment                                 
|                                                                               
|TranslationLanguages $3.50 per minute; plus one additional connection.        
|                                                                               
|Fax Service $1.00 page/participant                                             
|                                                                               
|Pre-Notification                                                               
|                                                                               
|Participant Registration (RSVP)                                                
|                                                                               
|Participant-Paid Pre-Registration (Enhanced RSVP)                              
|                                                                               
|Conference Casting
Small Audio - $500
Large Audio - $1000
Replay/Archive - $250
|                                                                               

TERM PLAN TERMS AND CONDITIONS



Discontinuance Without Liability

This plan may be discontinued prior to the expiration of the specified term without liability under the following conditions:



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Discontinuance With Liability

A "Customer" who has ordered a plan, but discontinues service before the expiration of the term plan, is subject to the appropriate shortfall penalty for the
current year and any remaining years in the term plan upon discontinuance of the term plan. If the "Customer" has exercised the First Year Termination Without Liability Clause listed above, then this
clause would not apply.

Expiration of the Term

The Customer's obligation to AT&T automatically expires when the term plan ends. Unless the Customer notifies AT&T at least 90 days prior to the expiration of the
term, service thereafter will be provided at the Volume Discounts Plan III rates as specified in AT&T Business Service Guide (formerly Tariff FCC No. 1).

Shortfall Penalty

If the "Customer" does not meet the Annual Revenue Commitment in any one year, the "Customer" will be billed the difference between the minimum annual revenue
commitment and the actual billed usage. In the event the customer has exercised the 'Discontinuance Clause With Out Liability during the first year", the shortfall penalty would not apply to the
current or remaining years. If the customer exercised the "New Plan" agreement, the new plan would supersede the previous agreement, and no shortfall penalty would apply for the previous agreement.
However, the terms and conditions do begin again with the new agreement and short fail penalties could apply as stated above.

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