Localization means the transformation of the called number to a format that can be understood by PSTN.
User in USA dials 90114420887874001, this the LOCALIZATION, the CUCM transforms the Called Number to +4420887874001 using the translation pattern, this is the GLOBALIZATION, the CUCM then transforms the Called Number to 90114420887874001 using the Transformation Pattern applied at the Gateway or SIP trunk configuration page, this the LOCALIZATION.
How the Calling Number is dislayed at the user UK?
In the CUCM located in UK we configure a Calling Party Transformation Pattern so that the calling number will be displayed as 00014085551001, NOT +14085551001 therefore the user is not aware about the + sign, this is the LOCALIZATION
But what about the missed call?
Case 1:
If you apply the Transformation Pattern at the Gateway or SIP Trunk Configuration Page under the Incoming Party Settings on CUCM:
Use the Calling Party Transformation CSS UK-CSS
The call at the user UK displays the calling number 00014085551001.
In the missed call, the user sees calling number 00014085551001.
Case 2:
If you apply the Transformation Pattern at the Phone Configuration Page on CUCM:
Number Presentation Transformation
Remote Number
Calling Party Transformation CSS UK-CSS
The call at the user UK displays the calling number 00014085551001.
In the missed call, the user sees calling number +14085551001.