A.1 Use case for tunnel establishment measurements

28.4023GPPPerformance Management (PM)Performance measurements for Evolved Packet Core (EPC) and non-3GPP access interworking systemRelease 17Telecommunication managementTS

It needs to setup secure tunnels between non-3GPP UE and remote tunnel endpoint once UE attaches to interworking system. The tunnel resides between the non-3GPP UE and ePDG. In order to guarantee the user experiences, the tunnel should be established before the data is transmitted. During the period of tunnel establishment, ePDG may reject the tunnel establishment due to QoS profile request or policy enforcement in AAA servers. Those rejections would impact subsequent traffic transmission and user experiences.
It is desirable for operators to get the indications before massive rejection happened.