MBS

MBS is 5G's answer to a basic inefficiency: when many devices in the same area all want the same content, sending it as separate unicast streams wastes the air interface. MBS (also written 5G MBS, the NR successor to LTE's eMBMS) lets the network transmit once and have many receivers pick it up — one-to-many over the radio. Introduced in Release 17, it covers both broadcast (sent to everyone in the coverage area, no per-device feedback) and multicast (sent to a defined group, with more reliability machinery).

The use cases are the ones where a crowd wants the same bits at the same time: live video to a stadium, software or firmware updates pushed to a fleet of devices, V2X safety messages to all vehicles in an area, and public-safety group communications. The efficiency win scales with audience size — the more receivers, the more spectrum you save versus unicasting to each. The practical reality is that broadcast features in cellular have historically struggled to get deployed widely (eMBMS never took off the way some hoped), so MBS adoption is worth watching rather than assuming.