##### 



Exhibit 10.2.4
 Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
  Amendment No. 46(CA) Rev. 3
SOW: þ No
    
    Date: June 1, 2007o Yes
 
 AMENDMENT
 TO
 CONTRACTOR SERVICES AGREEMENT
 FOR
 NUMBERING ADMINISTRATION CENTER / SERVICE
MANAGEMENT SYSTEM
 ANNUAL UPDATE TO CONVERSION FACTOR
 FOR THE PERIOD JUNE 1, 2007 TO MAY 31, 2008
  CONFIDENTIAL
 Page 1




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
  Amendment No. 46(CA) Rev. 3
SOW: þ No
    
    Date: June 1, 2007o Yes
 AMENDMENT
 TO
 CONTRACTOR SERVICES AGREEMENT FOR NUMBERING
ADMINISTRATION CENTER / SERVICE MANAGEMENT SYSTEM
 Annual Update to Conversion Factor
 For the Period June 1, 2007 to May 31, 2008
 1. PARTIES
 Revision Amendment Amending Agreement Second Amending Agreement Master Agreement Contractor Customer
 2. EFFECTIVENESS
 st Revision Effective
Date
 3. ANNUAL UPDATE
  CONFIDENTIAL
 Page 2




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
  Amendment No. 46(CA) Rev. 3
SOW:  þ No
    
    Date: June 1, 2007o Yes
  
    
    1.5723 for the period June 1, 2003 to May 31, 2004, as reflected in the Amending Agreement
    
    1.3612 for the period of June 1, 2004 to May 31, 2005, as reflected in Amendment No. 46
    
    1.2484 for the period of June 1, 2005 to May 31, 2006, as reflected in Revision 1 to
Amendment No. 46
    
    1.1274 for the period of June 1, 2006 to May 31, 2007, as reflected in Revision 2 to
Amendment No. 46
 1.1169.
 4. AMENDMENT AND RESTATEMENT
  5. RESERVATION
  CONFIDENTIAL
 Page 3




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
  Amendment No. 46(CA) Rev. 3
SOW:  þ No
    
    Date: June 1, 2007o Yes
  6. COMPLETION AND ACCEPTANCE CRITERIA
  N/A
    
    Functional Requirements SpecificationsN/A
    
    Requirements Traceability MatrixN/A
    
    External DesignN/A
    
    System DesignN/A
    
    Detailed DesignN/A
    
    Integration Test PlanN/A
    
    System Test PlanN/A
    
    Software Quality Assurance Program ReportN/A
    
    User DocumentationN/A
    
    Software Configuration Management PlanN/A
    
    Standards and Metrics
 7. IMPACTS ON MASTER AGREEMENT.
  ü
    
    Master AgreementNone
    
    Exhibit B Functional Requirements SpecificationNone
    
    Exhibit C Interoperable Interface Specificationü
    
    Exhibit E Pricing SchedulesNone
    
    Exhibit F Project Plan and Test Scheduleü
    
    Exhibit G Service Level RequirementsNone
    
    Exhibit H Reporting and Monitoring RequirementsNone
    
    Exhibit I Key PersonnelNone
    
    Exhibit J User Agreement FormNone
    
    Exhibit K External DesignNone
    
    Exhibit L Infrastructure/HardwareNone
    
    Exhibit M Software Escrow AgreementNone
    
    Exhibit O Statement of Work Cost Principles
 8. MISCELLANEOUS.
 CONFIDENTIAL
  Page 4




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
  Amendment No. 46(CA) Rev. 3
SOW:  þ No
    
    Date: June 1, 2007o Yes
 Continuation of Master Agreement and User Agreement
  Counterparts.
  Entire Agreement.
  [THIS SPACE INTENTIONALLY LEFT BLANK]
CONFIDENTIAL
 Page 5




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
  Amendment No. 46(CA) Rev. 3
SOW:  þ No
    
    Date: June 1, 2007o Yes
  CONTRACTOR: NeuStar, Inc.By:
   /s/ Michael OConnorIts:
     VP - Customer RelationsDate:

    6 June 2007CUSTOMER: Canadian LNP Consortium, Inc.By:
   /s/ Jacques SarrazinIts:
   PresidentDate:
 June 4/07
 CONFIDENTIAL
 Page 6




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
  Amendment No. 46(CA) Rev. 3
SOW:  þ No
    
    Date: June 1, 2007o Yes
    Amended and Restated Exhibit E to Master Agreement
  CONFIDENTIAL
 Page 7




---



##### 



EXHIBIT E
 PRICING SCHEDULES
 NPAC/SMS SERVICES
 , th




---



##### 



PRICING SCHEDULES
        , th




---



##### 



Schedule 1
 Service Element Fees/Unit Pricing
 Price
    
    PriceU.S.
    
    CanadianCategory
    
    Service Element
    
    Unit
    
    Dollars
    
    Dollars1. [* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *]2. [* * *][* * *]1
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]2
 Price inUSD foreach TNPortingEvent
    
    Price inApplicable Tiers
    
    Tier Start*
    
    Tier End*
    
    Within Tier
    
    CDNTier 1
    
    0
    
    2,200,000
    
    $[* * *]
    
    $[* * *]Tier 2
    
    2,200,001
    
    4,400,000
    
    $[* * *]
    
    $[* * *]Tier 3
    
    4,400,001
    
    6,600,000
    
    $[* * *]
    
    $[* * *]Tier 4
    
    6,600,001
    
    8,800,000
    
    $[* * *]
    
    $[* * *]Tier 5
    
    8,800,001
    
    11,000,000
    
    $[* * *]
    
    $[* * *]Tier 6
    
    11,000,001
    
    13,200,000
    
    $[* * *]
    
    $[* * *]Tier 7
    
    13,200,001
    
    15,400,000
    
    $[* * *]
    
    $[* * *]Tier 8
    
    15,400,001
    
    17,600,000
    
    $[* * *]
    
    $[* * *]Tier 9
    
    17,600,001 and above
    
    N/A
    
    $[* * *]
    
    $[* * *]
 
 *
    
    The above tier volumes represent cumulative TN Porting Events measured from [* * *]. The price described above
for each TN Porting Event is the price for each TN Porting Event within each Tier set forth above. [* * *]
    
    
    [* * *]
    
    
    
    [* * *]
    
    
    
    [* * *][* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *][* * *]3
    
    
    [* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *][* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *][* * *]4
    
    
    [* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *]
 , th




---



##### 



[* * *]5
    
    
    
    [* * *]
    
    $     [* * *]
    
    $     [* * *][* * *]
    
    
    
    [* * *]
    
    $     [* * *]
    
    $     [* * *][* * *]
    
    
    
    [* * *]
    
    $     [* * *]
    
    $     [* * *]3. [* * *][* * *]6
    
    
    
    [* * *]
    
    $     [* * *]
    
    $     [* * *][* * *]7
    
    
    
    [* * *]
    
    $     [* * *]
    
    $     [* * *]
 [* * *]
 [* * *]
 Price in USD foreach TN PortingEvent Within Tierfor Annual VolumeApplicable
    
    
    
    
    
    Exceeding [* * *]Tiers
    
    Tier Start*
    
    Tier End*
    
    in a Calendar Year
    
    Price in CDNTier 1
    
    0
    
    2,200,000
    
    $     [* * *]
    
    $     [* * *]Tier 2
    
    2,200,001
    
    4,400,000
    
    $     [* * *]
    
    $     [* * *]Tier 3
    
    4,400,001
    
    6,600,000
    
    $     [* * *]
    
    $     [* * *]Tier 4
    
    6,600,001
    
    8,800,000
    
    $     [* * *]
    
    $     [* * *]Tier 5
    
    8,800,001
    
    11,000,000
    
    $     [* * *]
    
    $     [* * *]Tier 6
    
    11,000,001
    
    13,200,000
    
    $     [* * *]
    
    $     [* * *]Tier 7
    
    13,200,001
    
    15,400,000
    
    $     [* * *]
    
    $     [* * *]Tier 8
    
    15,400,001
    
    17,600,000
    
    $     [* * *]
    
    $     [* * *]Tier 9
    
    17,600,001 and above
    
    N/A
    
    $     [* * *]
    
    $     [* * *]$     [* * *]
    
    $     [* * *]
 [* * *] [* * *]
 , th




---



##### 



[* * *]
 [* * *]
 Price in USD foreach TN PortingEventfor Annual VolumeApplicable
    
    
    
    
    
    Exceeding [* * *]Tiers
    
    Tier Start*
    
    Tier End*
    
    in a Calendar Year
    
    Price in CDNTier 1
    

0
    
    2,200,000
    
    $     [* * *]
    
    $     [* * *]Tier 2
    
    2,200,001
    
    4,400,000
    
    $     [* * *]
    
    $     [* * *]Tier 3
    
    4,400,001
    
    6,600,000
    
    $     [* * *]
    
    $     [* * *]Tier 4
    
    6,600,001
    
    8,800,000
    
    $     [* * *]
    
    $     [* * *]Tier 5
    
    8,800,001
    
    11,000,000
    
    $     [* * *]
    
    $     [* * *]Tier 6
    
    11,000,001
    
    13,200,000
    
    $     [* * *]
    
    $     [* * *]Tier 7
    
    13,200,001
    
    15,400,000
    
    $     [* * *]
    
    $     [* * *]Tier 8
    
    15,400,001
    
    17,600,000
    
    $     [* * *]
    
    $     [* * *]Tier 9
    
    17,600,001 and above
    
    N/A
    
    $     [* * *]
    
    $     [* * *]
 [* * *] [* * *] [* * *]
 , th




---



##### 



, th




---



##### 



Schedule 2
 Training Charges
 Price
    
    PriceU.S.
    
    CanadianService Element
    
    Unit
    
    Dollars
    
    Dollars[* * *]* [* * *]
    
    [* * *]
    
    $     [* * *]
    
    $     [* * *][* * *]* [* * *]89
    
    [* * *]
    
    $     [* * *]
    
    $     [* * *]
 
 *
    
    Training consists of LTI User Training lasting 8 to 12 hours. , th




---



##### 



Schedule 3
 Interoperability Testing *
 PriceCategory & Service
    
    
    
    
    
    
    
    
    
    CanadianElement
    
    Unit
    
    Price
    
    Dollars[* * *][* * *]
    
    
    
    [* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *][* * *]
    
    
    
    [* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *][* * *][* * *]
    
    
    
    [* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *][* * *]
    
    
    
    [* * *]
    
    
    $
    [* * *]
    
    
    $
    [* * *]
 *
    
    [* * *] 
 1
    
    [* * *]2
    
    The TN Porting Event [* * *]The TN Porting Event [* * *]3
    
    An Ad Hoc Report [* * *]4
    
    [* * *]5
    
    [* * *]6
    
    The one-time Log-on ID [* * *]7
    
    The Mechanized Interface [* * *]8
    
    [* * *]9
    
    [* * *] , th
 E-7




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked [***]
and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
 Amendment No. 46(CA) Rev. 3
    
    Date: June 1, 2007
 SOW: þ No  o Yes
    Amended and Restated Exhibit G to Master Agreement
 CONFIDENTIAL




---



##### 



EXHIBIT G
 SERVICE LEVEL REQUIREMENTS
 NPAC/SMS
 Service
    
    
    
    
    
    
    
    
    
    ReportAffecting/
    
    
    
    
    
    
    
    
    
    Frequency andNon-Service
    
    Performance
    
    
    Performance Credit
    
    
    Performance CreditNo.
    
    Procedure
    
    Service Commitment Level
    
    Affecting
    
    Credit US Dollars
    
    
    Canadian Dollars
    
    
    Calculation Interval1.
    
    Service Availability
    
    Maintain a 99.9% minimum Service Availability
    
    Service Affecting
    
    >99.85% but <99.90%:
 $[* * *];
    
    >99.85% but <99.90%: 
$[* * *];
    
    Monthly(customer)
    
    
    
    
    
    >99.80% but <99.85%: 
$[* * *];
    
    >99.80% but <99.85%: 
$[* * *];>99.75% but <99.80%: 
$[* * *];
    
    >99.75% but <99.80%: 
$[* * *];>99.70% but <99.75%: 
$[* * *];
    
    >99.70% but <99.75%: 
$[* * *];>99.65% but <99.70%: 
$[* * *];
    
    >99.65% but <99.70%: 
$[* * *];>99.60% but <99.65%: 
$[* * *];
    
    >99.60% but <99.65%: 
$[* * *];<99.60%: $[* * *]
    
    <99.60%: $[* * *]




---



##### 



Service
    
    
    
    
    
    ReportAffecting/
    
    
    
    
    
    Frequency andNon-Service
    
    Performance
    
    Performance Credit
    
    Performance CreditNo.
    
    Procedure
    
    Service Commitment Level
    
    Affecting
    
    Credit US Dollars
    
    Canadian Dollars
    
    Calculation Interval2.
    
    Scheduled
Service
Unavailability
(Customer)
    
    Scheduled Service Unavailability
will be equal to or less than 20
hours per calendar quarter, or such
longer period otherwise agreed to
by the Parties, provided that such
twenty (20) hour period (each, a 20
Hour Period) shall not include time
reasonably required for release
implementations, data rebuilds, and
other non-routine tasks (the time for
which shall be agreed to on a case
by case basis). Contractor shall, not
less than ten (10) business days
prior to, and not less than four (4)
business days after, each Scheduled
Service Unavailability event,
provide to Customer a request for
maintenance and report,
respectively, both in the form of
Annex A attached to this Exhibit G.
Contractor shall not proceed with
the proposed Scheduled Service
Unavailability unless it has received
prior written approval (e-mail is
acceptable) from Customer for its
request for maintenance, which
approval shall not be unreasonably
withheld. For greater certainty, for
any Scheduled Service
Unavailability in excess of 20 hours
in each 20 Hour Period, Customer
shall be entitled to enforce all
remedies available to it, including
without limitation Performance
Credits as set forth in this SLR 2.
No Scheduled Service
Unavailability event shall exceed
ten (10) hours. Each such event
shall be scheduled in advance and
shall be coordinated with each
Users maintenance schedule.
    
    Service
Affecting
    
    $[* * *] for each hour or
portion thereof in excess
of approved Scheduled
Service Unavailability
or such longer period
otherwise agreed to by
the Parties
    
    $[* * *] for each hour or
portion thereof in excess
of approved Scheduled
Service Unavailability
or such longer period
otherwise agreed to by
the Parties
    
    Monthly3.
    
    SOA/LSMS
Acknowledge-
ment Response
Times
(Customer)
    
    Response time (i.e., means NPAC
processing time) for 95% of the
responses will be equal to or less
than 3 seconds, except for
miscellaneous transactions, such as
queries, audits and edits
    
    Service
Affecting
    
    $[* * *]
    
    $[* * *]
    
    Monthly4.
    
    LSMS
Broadcast Time
(Customer)
    
    A mean time maximum of 60
seconds from activation to broadcast
    
    Service
Affecting
    
    $[* * *]
    
    $[* * *]
    
    Monthly5.
    
    SOA to NPAC
Interface
Transaction
Rates
(Customer)
    
    To the extent there is sufficient
load, maintain, for 95% of the
CMIP transactions, a rate of 4
CMIP transactions per second
(sustained) for each SOA to NPAC
SMS interface association; however,
this interface requirement does not
apply when there are at least 40
CMIP transactions per second
(sustained) for a single NPAC/SMS
region. Neither criterion applies if
throughput is impacted by delays
caused by all Users.
    
    Service
Affecting
    
    $[* * *]
    
    $[* * *]
    
    Monthly




---



##### 



Service
    
    
    
    
    
    ReportAffecting/
    
    
    
    
    
    Frequency andNon-Service
    
    Performance
    
    Performance Credit
    
    Performance CreditNo.
    
    Procedure
    
    Service Commitment Level
    
    Affecting
    
    Credit US Dollars
    
    Canadian Dollars
    
    Calculation Interval6.
    
    NPAC to
LSMS Interface
Transaction
Rates
(Customer)
    
    To the extent there is sufficient

offered load, maintain, for 95% of 
the CMIP transactions, a rate of 4
CMIP transactions per second
(sustained) over each NPAC/SMS 
to Local SMS interface association; 
however, this interface requirement 
does not apply when there are at 
least 156 CMIP transactions per 
second (sustained) for a single
NPAC/SMS region. Neither 
criterion applies if throughput is 
impacted by delays caused by all
Users.
    
    Service
Affecting
    
    $[* * *]
    
    $[* * *]
    
    Monthly7.
    
    SOA/LSMS
Interface
    
    Maintain an Interface Availability at
a minimum of 99.9%
    
    Service
Affecting
    
    >99.85% but <99.90%: 
$[* * *];
    
    >99.85% but
 <99.90%: 
$[* * *];
    
    MonthlyAvailability
(User)
    
    
    
    
    
    >99.80% but <99.85%: 
$[* * *];
    
    >99.80% but <99.85%: 
$[* * *];>99.75% but <99.80%: 
$[* * *];
    
    >99.75% but <99.80%:
 $[* * *];>99.70% but <99.75%: 
$[* * *];
    
    >99.70% but <99.75%:
 $[* * *];>99.65% but <99.70%: 
$[* * *];
    
    >99.65% but <99.70%: 
$[* * *];>99.60% but <99.65%: 
$[* * *];
    
    >99.60% but <99.65%: 
$[* * *];<99.60%:
$[* * *]
    
    <99.60%:
$[* * *]8.
    
    Unscheduled
Backup
Cutover time
(Customer)
    
    A maximum of 10 minutes to 
cutover to the backup site
    
    Service
Affecting
    
    $[* * *]
    
    $[* * *]
    
    Per Event9.
    
    NPAC/SMS
Partial Disaster
Restoral
Interval
(Customer)
    
    Partial restoration will be equal to or
less than 24 hours (Partial 
restoration meaning the capability 
of receiving, processing and 
broadcasting updates)
    
    Service
Affecting
    
    $[* * *] for each day or
portion thereof in excess
of 24 hours
    
    $[* * *] for each day or
portion thereof in
excess of 24 hours
    
    Per Event10.
    
    NPAC/SMS
Full Disaster
Restoral
(Customer)
    
    Full restoration will occur at a
maximum of 48 hours
    
    Service
Affecting
    
    $[* * *] for each day or
portion thereof in excess
of 24 hours
    
    $[* * *] for each day or
portion thereof in
excess of 24 hours
    
    Per Event11.
    
    RESERVED12.
    
    User Problem
Resolution
    
    Minimum 80% calls during Normal
Business Hours answered by live
operators within 10 seconds
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Monthly13.
    
    RESERVED14.
    
    User Problem
Resolution
    
    99.0% callback within 30 minutes 
for requests made during other than 
Normal Business Hours
    
    Non Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Monthly15.
    
    User Problem
Resolution
    
    A minimum of 99.5% of all 
commitments to get back to the 
User after the initial contact will be
met
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Monthly16.
    
    RESERVED17.
    
    RESERVED18.
    
    System
Security
    
    Monitor and record unauthorized
system access
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Per Event




---



##### 



Service
    
    
    
    
    
    ReportAffecting/
    
    
    
    
    
    Frequency andNon-Service
    
    Performance
    
    Performance Credit
    
    Performance CreditNo.
    
    Procedure
    
    Service Commitment Level
    
    Affecting
    
    Credit US Dollars
    
    Canadian Dollars
    
    Calculation Interval19.
    
    System
Security
    
    Remedy logon security permission
errors immediately after User
notification
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Per Event20.
    
    RESERVED21.
    
    Scheduled
Service
Unavailability
Notification
    
    Notice of Scheduled Service
Unavailability for routine
maintenance of NPAC/SMS to be
given a minimum of 2 weeks in
advance.
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Per EventNotice of Scheduled Service
Unavailability for non-routine
maintenance of NPAC/SMS to be
given as follows:     During Normal Business
Hours  a minimum of 7 days
in advance      During Non-Normal
Business Hours         a minimum of 24
hours in advance22.
    
    Unscheduled
Service
Unavailability
Notification
    
    Notify User within 15 minutes of
detection of an occurrence of
unscheduled Service Unavailability
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Per Event23.
    
    Unscheduled
Service
Unavailability
Notification
    
    Provide 30-minute updates of
NPAC status following an
occurrence of unscheduled Service
Unavailability through recorded
announcement and client bulletins
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Per Event24.
    
    RESERVED25.
    
    RESERVED26
    
    RESERVED27.
    
    RESERVED




---



##### 



Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
 Amendment No. 46(CA) Rev. 3
    
    Date: June 1, 2007
 SOW: þ No  o Yes
    Amended and Restated Section 6.1(c) of the Master Agreement
 CONFIDENTIAL




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ARTICLE 6  PRICING AND ADJUSTMENT
      [* * *] [* * *]
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Pursuant to 17 CFR 240.24b-2, confidential information has been omitted in places marked
[***] and has been filed separately with the Securities and Exchange Commission pursuant to a
Confidential Treatment Application filed with the Commission.
 Amendment No. 46(CA) Rev. 3
    
    Date: June 1, 2007
 SOW: þ No  o Yes
    Amended and Restated Article 16 of the Master Agreement
 CONFIDENTIAL




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ARTICLE 16  DELAYS; PERFORMANCE CREDITS AND CORRECTIVE REPORTING; DEFAULTS; FORCE MAJEURE
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