Reliable transmission of multicast and broadcast services

A wireless device comprising:

• one or more processors;
• and
• memory storing instructions that, when executed by the one or more processors, cause the wireless device:
• receive parameters, from a base station, comprising:
• a radio network temporary identifier (RNTI) associated with a multicast and broadcast service (MBS) session;
• a first scrambling identity associated with the MBS session;
• and
• a second scrambling identity associated with unicast transmissions;
• receive, based on the RNTI, a group common downlink control information (DCI) scheduling a transport block (TB) of the MBS session;
• based on the group common DCI being received based on the RNTI, determine a scrambling identity for the TB being equal to the first scrambling identity;
• and
• receive the TB being scrambled with a scrambling sequence initialized by:
• the determined scrambling identity;
• and
• the RNTI.