I Type II Type IIi Hybrid Type II SmartZone Type II SmartZone OmniLink Standard These systems exhibit some of the characteristics of a high tier trunked radio system but not all features. Therefore, they are suitable for small deployments where users are expected to use the entire network available (such as a private system covering a campus or town). Because of their lack of advanced features they generally are not suited to mission critical deployments, public access mobile radio (PAMR) type operation or uncoordinated shared user types. DMR/dPMR true Tier 3/Mode 3 protocols are intended eventually to migrate into the "Advanced Mature high end" list below but today (2015) cannot be classified as such due to major interoperability issues, lack of mature protocol and lack of clearly defined user interface protocol. OpenSky System APCO Project 16 dPMR Mode 3 DMR Tier III Kenwood NEXEDGE Digital trunked radio Icom IDAS Digital trunked Land Mobile Radio Hytera Motorola, Motorola Capacity Plus, Motorola Connect Plus iDEN (integrated Digital Enhanced Network) Advanced systems Some trunked radio protocols provide additional reliability and security. NXDN Common Air Interface (CAI) was accepted at the meeting of the ITU-R (International Telecommunication Union Radiocommunications Sector) held in November 2016 and it has been added to Report M.2014-3, published in February 2017. It is an open, multi-vendor protocol widely adopted in mission-critical applications in Japan, USA and mainland Europe. Other protocols include: MPT-1327 TETRA APCO Project 25 TETRAPOL Notes Radio resource management Radio networks