C.7 Information storage

23.2723GPPCircuit Switched (CS) fallback in Evolved Packet System (EPS)Release 17Stage 2TS

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

C.7.1 HSS

The following table specifies the HSS data defined per UE to support SMS in MME.

Table C.7.1-1: HSS data

Field	Description
SMS Subscription Parameters	SMS subscription parameters, e.g. SMS teleservice, SMS barring list.
Network Access Mode (NAM)	Indicates whether the subscription includes subscriber data allowing for accessing PS and or CS domain. NOTE 2
PS and SMS only	Indicates a subscription which is limited to PS domain services and to SMS service via the CS and the PS domain. NOTE 2
MME Registered for SMS	Indicates that MME has been registered for SMS in the HSS

NOTE 1: When the UE is not reachable in the MME, the HSS sets the MNRF in the Message Waiting Data (MWD) since the MME is registered as an MSC.

NOTE 2: If "PS and SMS only" is set for this subscriber, NAM is set to "CS+PS".

When the HSS functionality for "SMS in the MME" is enabled, the HSS will include an "SMS in MME" feature indication along with the UE subscription information to the MME.

C.7.2 MME

The following table specifies the MME data defined per UE to support SMS in MME.

Table C.7.2-1: MME Context for SMS

Field	Description
SMS Subscription Data	SMS subscription parameters, e.g. SMS teleservice, SMS barring list.
MME Registered for SMS	Indicates that MME has been registered for SMS in the HSS
MNRF-MME	Indicates whether activity from the UE shall be reported to the HSS.
Network Access Mode (NAM)	Indicates whether the subscription includes subscriber data allowing for access to PS and or CS domain. NOTE 1
PS and SMS only	Indicates a subscription which is limited to PS domain services and to SMS service via the CS and the PS domain. NOTE 1
SMS in MME Support	Capability of the HSS to support the SMS in MME feature

NOTE 1: If "PS and SMS only" is set for this subscriber, NAM is set to "CS+PS".