6.3.23 EASDF discovery and selection

Multiple instances of EASDF may be deployed in a network. NF consumers mentioned in this clause are SMF(s) or I-SMF in the case that I-SMF based Local Offloading Management applies..

In the case that I-SMF based Local Offloading Management applies, EASDF discovery and selection is only performed by the selected I-SMF.

The NF consumers shall utilize the NRF to discover EASDF instance(s) unless EASDF information is available by other means, e.g. locally configured on the NF consumer. The EASDF selection function in NF consumers or SCP selects an EASDF instance based on the available EASDF instances.

The following factors may be considered by the NF consumer or SCP for EASDF selection:

• S-NSSAI.
• DNN.
• the N6 IP address of the EASDF.

NOTE: The IP address of the EASDF is not used for EASDF discovery. It can be used is to select an EASDF that is "IP near" to the PSA of the PDU Session.

• The N6 IP address of the PSA UPF.
• Location as per NF profile.
• DNAI (if exist).
• Supported DNS security protocols (if existing).