Meaning of Device Reachability type DATA

[DucHuySET]

Hi everyone,

I need some clarification on the exact purpose of Reachability for DATA:

• Does it indicate that the UE can actively send and receive DATA (i.e., a PDU session with an internet DNN has been established, so the UE can receive notifications from services like Facebook, YouTube, etc.)?
• Or does it mean that the UE is known by the Network (AMF) (i.e., the UE is in CM-Connected state or the AMF has tracking/routing information to process paging), thus the UE is ready and able to establish a PDU session with an internet DNN to receive DATA?

I’m confused because:

1. In the CAMARA API Device Reachability Status, the use case indicates the API’s purpose is to check if the UE can receive DATA in order to send necessary data.
2. However, this API is actually implemented using the 3GPP API UE_Reachability for DATA. According to TS 23.502 (Table 4.15.3.1-1), this API monitors UE events like transitions to CM-CONNECTED or when the UE becomes reachable for paging. This state does not guarantee an active internet PDU session or the UE’s ability to receive DATA, but only informs about the UE’s readiness and potential to establish such a session.

Could someone clarify which interpretation is correct?

Thank you!