Methods by which User Plane (UP) management information is exchanged between an Application Function (AF) supporting one or more applications and a Slice Management Function (SMF) configured to manage traffic flows in a given slice of the network. The exchange of UP management information may be initiated from either the AF or the SMF. In the case of AF-initiated information exchange, the UP management information provided by the AF may comprise traffic requirements of applications supported by the AF. In the case of SMF-initiated information exchange, the UP management information provided by the SM may comprise operator policy information or events, and the AF may respond with information of traffic requirements of applications supported by the AF.