An integrated user-centric service unit (IUSU) supports end users to define network and service capability profiles according to their own necessities. Fixed, mobile and satellite convergence (FMSC) is the capability of IUSU in supporting multiple access technologies used by various devices. This Recommendation specifies the enhanced architecture, procedures and security considerations in support of IUSU for FMSC, in the context of IMT-2020 networks and beyond. The radio aspects are out of the scope of this Recommendation.