WPS Session Critical Information

Following are the important WPS session critical information:

  • SMF does not identify a session as WPS during establishment and hence priority tagging based on establishment is not possible on the SMF. SMF is not aware of MCS and MPS subscription or establishment causes.

  • SMF does not support any special access rights enforcement for WPS session configuration or for WPS session monitoring.

  • SMF does not support any hardware isolation between WPS and non-WPS users.

  • IPSEC support on N4 is not supported for WPS. IPSEC is enabled at interface/peer level.

  • Upgrade the UPF before the SMF for the SBI message priority feature to work smoothly. Otherwise, configure the new priority values on the SMF only after UPF is upgraded. UPF supports Message Priority (MP) values 1 to 3 in older releases. If SMF gets upgraded first, and new configuration gets applied on the N4 interface, then UPF ignores new values and treats those sessions as normal call.

  • If new priority values are configured post upgrade, then on the UPF, old sessions uses old MP values that were applied before the upgrade and new sessions uses new MP values. Due to this there can be conflicting MP values for sessions of same type and session recovery based on the priority does not work as expected untill MP values of old sessions gets updated. MP values of old sessions gets updated during subsequent N4 modification from SMF.

  • If a message priority profile is associated to any QoS profile or DNN profile or WPS profile, SMF enables this SBI message priority feature. Else, the SBI message priority feature remains disabled and SMF sends the hardcoded values as before on N4 and GTP interfaces.