The ITU has defined three service categories for 5th GenerationNew Radio(5GNR) mobile communications: Enhanced Mobile Broadband( eMBB), Ultra-High Reliability and Low Latency Communications( uRLLC) and Massive Machine-Type Communications (mMTC).
Massive Machine-Type Communication (mMTC) involves services that require a high connection density. This can be as high as one million MTC components per square kilometer. Typical examples are smart cities, smart homes, smart agriculture, logistics, fleet management and water supply. mMTC services serve the further development of digital society and the demand for new high- performance services.
If machine communication is about large numbers of low-cost and low-energy devices and large amounts of data, critical machine-type communication( cMTC), mission-critical machine-type communication or ultra-reliable machine-type communication( uMTC) is about extremely short latency for real-time control of machines, high availability and reliability, and end-to-end latencies in the millisecond range.