E.3 Multiple Sessions

23.5483GPP5G System Enhancements for Edge ComputingRelease 17Stage 2TS

The URSP rules provided by 5GC to the UE are defined to cover both 5GS as well as EPS when interworking is applied. In EPS there is no possibility to provide new URSP rules to the UE, instead according to clauses 5.15.5.3 and 5.17.1.2 of TS 23.501 [2], the URSP rules provided to the UE when it was registered in 5GC can also be used when the UE is registered in EPC if HPLMN uses URSP (see TS 24.526 [8]).

AF guidance of URSPs may not take effect if the UE is in EPS and the UE does not use the URSP rules on EPS (see TS 24.526 [8] 4.4.2 for the use of URSP in EPS). Therefore, it is not deterministic when they will take effect, since PCF could have issued the URSP rules when the UE was on EPS (where URSP rules cannot be sent).