##### 



Exhibit 10.2.3
  
 AMENDMENT
 TO
 CONTRACTOR SERVICES AGREEMENT
 FOR
 NUMBERING ADMINISTRATION CENTER / SERVICE
MANAGEMENT SYSTEM
 ANNUAL UPDATE TO CONVERSION FACTOR
 FOR THE PERIOD JUNE 1, 2006 TO MAY 31, 2007
 Page 1




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##### 



Amendment No. 46(CA) Rev. 2
    
    Date: June 1, 2006SOW:    þNooYes
 AMENDMENT
 TO
 CONTRACTOR SERVICES AGREEMENT FOR NUMBERING
ADMINISTRATION CENTER / SERVICE MANAGEMENT SYSTEM
 Annual Update to Conversion Factor
 For the Period June 1, 2006 to May 31, 2007
 1. PARTIES
  2. EFFECTIVENESS
 st
 3. ANNUAL UPDATE
 1.5723
  Page 2




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##### 



Amendment No. 46(CA) Rev. 2
    
    Date: June 1, 2006SOW:    þNooYes
 1.3612 1.2484 1.1274
 4. AMENDMENT AND RESTATEMENT
  5. RESERVATION
  6. COMPLETION AND ACCEPTANCE CRITERIA
             Page 3




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##### 



Amendment No. 46(CA) Rev. 2
    
    Date: June 1, 2006SOW:    þNooYes
 7. IMPACTS ON MASTER AGREEMENT.
  þ
   þ
  þ
        8. MISCELLANEOUS.
 Continuation of Master Agreement and User Agreement
  Counterparts.
  Page 4




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##### 



Amendment No. 46(CA) Rev. 2
    
    Date: June 1, 2006SOW:    þNooYes
 Entire Agreement.
  [THIS SPACE INTENTIONALLY LEFT BLANK]
 Page 5




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##### 



Amendment No. 46(CA) Rev. 2
    
    Date: June 1, 2006SOW:    þNooYes
  CONTRACTOR: NeuStar, Inc.By:
    
    /s/ Michael OConnorIts:
    
    VP-Customer RelationsDate:
    
    19 July 2006CUSTOMER: Canadian LNP Consortium, Inc.By:
    
    /s/ Jacques SarazinIts:
    
    PresidentDate:
    
    June 30/06
 Page 6




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##### 



Amendment No. 46(CA) Rev. 2
    
    Date: June 1, 2006SOW:    þNooYes
    Amended and Restated Exhibit E to Master Agreement
 Page 7




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##### 



EXHIBIT E
 PRICING SCHEDULES
 NPAC/SMS SERVICES




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##### 



PRICING SCHEDULES
        E-9




---



##### 



Schedule 1
 Service Element Fees/Unit Pricing
 PriceU.S.
    
    PriceCategory
    
    Service Element
    
    Unit
    
    Dollars
    
    Canadian Dollars1. [* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]1
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *]2. [* * *][* * *]2
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]3
 Price in USDfor each TNApplicable
    
    
    
    
    
    Porting Event
    
    Price inTiers
    
    Tier Start*
    
    Tier End*
    
    Within Tier
    
    CDN[* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *]* The above tier volumes represent cumulative TN Porting Events measured from September 1, 2005.
The price described above for each TN Porting Event is the price for each TN Porting Event within each
Tier set forth above.[* * *]
    
    
    
    [* * *]
    
    [* * *]
    
    [* * *]$[* * *]
    
    $[* * *][* * *]4
    
    
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    $[* * *]
    
    $[* * *][* * *]5
    
    
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]6
    
    
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    
    
    [* * *]
    
    $[* * *]
    
    $[* * *]3. [* * *][* * *]7
    
    
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]8
    
    
    
    [* * *]
    
    $[* * *]
    
    $[* * *]
 E-10




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##### 



E-11




---



##### 



Schedule 2
 Training Charges
 Price
    
    PriceU.S.
    
    CanadianService Element
    
    Unit
    
    Dollars
    
    Dollars[* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]9 10
    
    [* * *]
    
    $[* * *]
    
    $[* * *]
 
 *
    
    Training consists of LTI User Training lasting 8 to 12 hours. E-12




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##### 



Schedule 3
 Interoperability Testing *
 PriceCanadianCategory & Service Element
    
    Unit
    
    Price
    
    Dollars[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *][* * *]
    
    [* * *]
    
    $[* * *]
    
    $[* * *]
  
 1
    
    Monthly port charges [* * *]2
    
    [* * *]3
    
    The TN Porting Event [* * *]The TN Porting Event [* * *]4
    
    An Ad Hoc Report [* * *]5
    
    [* * *]6
    
    [* * *]7
    
    The one-time Log-on ID [* * *]8
    
    The Mechanized Interface [* * *]9
    
    [* * *]10
    
    [* * *] E-13




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##### 



Amendment No. 46(CA) Rev. 2
    
    Date: June 1, 2006SOW:    þNooYes
    Amended and Restated Exhibit G to Master Agreement
 Page 14




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##### 



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
(Customer)
    
    Maintain a 99.9%
minimum Service
Availability
    
    Service Affecting
    
    >99.85% but
<99.90%: $[* *
*];
>99.80% but
<99.85%: $[* *
*];
>99.75% but
<99.80%: $[* *
*];
>99.70% but
<99.75%: $[* *
*];
>99.65% but
<99.70%: $[* *
*];
>99.60% but
<99.65%: $[* *
*];
<99.60%: $[* * *]
    
    >99.85% but
<99.90%: $[* *
*];
>99.80% but
<99.85%: $[* *
*];
>99.75% but
<99.80%: $[* *
*];
>99.70% but
<99.75%: $[* *
*];
>99.65% but
<99.70%: $[* *
*];
>99.60% but
<99.65%: $[* *
*];
<99.60%: $[* * *]
    
    Monthly




---



##### 



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
Acknowledgement
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)
    
    Maintain a minimum of 2
transactions per second
per User SOA for 95%
of the transactions.
    
    Service Affecting
    
    $[* * *]
    
    $[* * *]
    
    Monthly6.
    
    NPAC to LSMS
Interface
Transaction Rates
(Customer)
    
    Maintain a minimum of
10 transactions per
second per User LSMS
for 95% of the
transactions (excluding
the impact of delays
caused by 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 Interval7.
    
    SOA/LSMS Interface
Availability
(User)
    
    Maintain an Interface
Availability at a
minimum of 99.9%
    
    Service Affecting
    
    >99.85% but
<99.90%: $[* *
*];
>99.80% but
<99.85%: $[* *
*];
>99.75% but
<99.80%: $[* *
*];
>99.70% but
<99.75%: $[* *
*];
>99.65% but
<99.70%: $[* *
*];
>99.60% but
<99.65%: $[* *
*];
<99.60%: $[* * *]
    
    >99.85% but
<99.90%: $[* *
*];
>99.80% but
<99.85%: $[* *
*];
>99.75% but
<99.80%: $[* *
*];
>99.70% but
<99.75%: $[* *
*];
>99.65% but
<99.70%: $[* *
*];
>99.60% but
<99.65%: $[* *
*];
<99.60%: $[* * *]
    
    Monthly8.
    
    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 Event19.
    
    System Security
    
    Remedy logon security
permission errors
immediately after User
notification
    
    Non-Service
Affecting
    
    [* * *]
    
    [* * *]
    
    Per Event20.
    
    RESERVED




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##### 



Service
    
    
    
    
    
    ReportAffecting/
    
    
    
    
    
    Frequency andNon-Service
    
    Performance
    
    Performance Credit
    
    Performance CreditNo.
    
    Procedure
    
    Service Commitment Level
    
    Affecting
    
    Credit US Dollars
    
    Canadian Dollars
    
    Calculation Interval21.
    
    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




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##### 



Amendment No. 46(CA) Rev. 2


    
    
    
    Date:
    
    June 1, 2006SOW:
    
    þNooYes
    Amended and Restated Section 6.1(c) of the Master Agreement
 Page19




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##### 



ARTICLE 6  PRICING AND ADJUSTMENT




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##### 








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##### 



Amendment No. 46(CA) Rev. 2


    
    
    
    Date:
    
    June 1, 2006SOW:
    
    þNooYes
    Amended and Restated Article 16 of the Master Agreement
 Page22




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##### 



ARTICLE 16  DELAYS; PERFORMANCE CREDITS AND CORRECTIVE REPORTING; DEFAULTS; FORCE
MAJEURE
  i.e.,




---



##### 



i.e.,