A session type manager, STM, entity of a core network, CN, of a mobile communication network, the mobile communication network including an access network, AN, and the CN, the STM entity configured to: control a connectivity of multiple transmission bearers over at least two access points, AP, of a same AN technology and the CN, based on a selective assignment of the multiple transmission bearers, wherein the selective assignment of the multiple transmission bearers is amongst at least two transmission bearers from the at least two AP of the same AN technology and at least one transmission bearer of the CN, the at least two transmission bearers from the at least two AP of the same AN technology and the at least one transmission bearer of the CN belonging to a single packet data unit, PDU, session; and provide information on an operation mode of the PDU session to be used by a user equipment, UE, the operation mode of the PDU session defining session configuration information for a transmission of a data traffic over the at least two transmission bearers from the at least two AP of the same AN technology and the at least one transmission bearer of the CN, wherein the session configuration information is related to an operation mode of the session of the UE to be set up, the operation mode being selected by the STM entity as either a preemptive mode or a simultaneous mode or a reliability mode; the preemptive mode is related to a reservation of resources in the multiple transmission bearers between the AN and the CN for the session of the UE to be set up; the simultaneous mode is related to a simultaneous usage of selected transmission bearers amongst the multiple transmission bearers between the AN and the CN; and the reliability mode is related to a redundancy on the transmission of data traffic of the selected transmission bearers amongst the multiple transmission bearers between the AN and the CN. control a connectivity of multiple transmission bearers over at least two access points, AP, of a same AN technology and the CN, based on a selective assignment of the multiple transmission bearers, wherein the selective assignment of the multiple transmission bearers is amongst at least two transmission bearers from the at least two AP of the same AN technology and at least one transmission bearer of the CN, the at least two transmission bearers from the at least two AP of the same AN technology and the at least one transmission bearer of the CN belonging to a single packet data unit, PDU, session; and provide information on an operation mode of the PDU session to be used by a user equipment, UE, the operation mode of the PDU session defining session configuration information for a transmission of a data traffic over the at least two transmission bearers from the at least two AP of the same AN technology and the at least one transmission bearer of the CN, wherein the session configuration information is related to an operation mode of the session of the UE to be set up, the operation mode being selected by the STM entity as either a preemptive mode or a simultaneous mode or a reliability mode; the preemptive mode is related to a reservation of resources in the multiple transmission bearers between the AN and the CN for the session of the UE to be set up; the simultaneous mode is related to a simultaneous usage of selected transmission bearers amongst the multiple transmission bearers between the AN and the CN; and the reliability mode is related to a redundancy on the transmission of data traffic of the selected transmission bearers amongst the multiple transmission bearers between the AN and the CN.