Section: A.6 Guidelines regarding use of need codes
Content: The following rule provides guidance for determining need codes for optional downlink fields: - if the field needs to be stored by the UE (i.e. maintained) when absent: - use Need M (=Maintain); - else, if the field needs to be released by the UE when absent: - use Need R (=Release); - else, if UE shall take no action when the field is absent (i.e. UE does not even need to maintain any existing value of the field): - use Need N (=None); - else (UE behaviour upon absence does not fit any of the above conditions): - use Need S (=Specified); - specify the UE behaviour upon absence of the field in the procedural text or in the field description table.