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Messaging Basics

What is HLR?

HLR is a Data Service provided by CLX. It’s a great way to validate and cleanse your mobile number databases and to obtain vital information regarding the numbers in your list. Here is what using HLR can provide you:

  • The country and the Mobile Network Operator (MNO) that the number currently belongs to
  • The Mobile Country Code (MCC) and Mobile Network Code (MNC) for the number’s current network
  • An indication as to whether the number has been ported from one network to another
  • The original network that a mobile number belonged to when it was first registered
  • Identification of invalid numbers due to the number never being registered or the number being deactivated (Unknown Subscriber)
  • Identification of temporary errors that would prevent immediate SMS delivery (e.g. Absent Subscriber that arises if the mobile phone is turned off or out of coverage for an extended period of time
  • Identification of the current network even if a temporary error (such as Absent Subscribers) is returned
  • The MSC address that currently serves the mobile number; this is particularly useful for identifying numbers roaming in another country, as the foreign number that the number is logged onto can also be identified using this data

Please note:

  • Accurate HLR data cannot be retrieved for mobile numbers in Brazil, Canada and the USA. Regularly-updated Mobile Number Portability (MNP) databases are queried instead of performing HLR queries for these countries
  • Finding out the following information is network dependent: discovering a number’s MNO, whether or not a number has been ported from one network to another, if a number is roaming and identifying temporary errors

You can find out more by clicking here.