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TechSpec
  • Foreword
  • 1 Scope
  • 2 References
  • 3 Definitions and abbreviations
  • 4 Handling of Follow Me
    • 4.1 General
    • 4.2 Information Flows
    • 4.3 Handling of FM control in HLRa and FFNb
      • 4.3 Handling of FM control in HLRa and FFNb
      • 4.3.1 Handling of FM control in HLRa
      • 4.3.2 Handling of FM control in FFNb
    • 4.4 USSD interworking and Cross-phase compatibility
  • 5 Information stored in the network entities
  • B.1 General principles
  • B.2 Information Elements used in the messages
  • B.3 Messages Contents of the FM Request
  • B.4 Messages Contents of the HLR-FM-Request
  • B.5 Contents and Format of the USSD String of the USSD-Notify
  • B.6 Inter-process Message Init-Notify

4.3 Handling of FM control in HLRa and FFNb

23.0943GPPFollow-Me (FM)Release 17Stage 2TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

HLRa and FFNb can both receive FM control messages, based on USSD. The USSD handler in each entity analyses the Service Code contained in the USSD string and, recognising the Service Code for FM, invokes the FM USSD application.

The FM control messages and their contents are given in Annex B (normative).