This document specifies the MAC layer protocol for a logical control channel on the Um2 interface. This document specifies the following aspects of the logical control channel MAC layer:

• Logical channel structure

• Burst descriptions and field definitions

• Logical control channel procedures

• Logical control channel messages

The information necessary to enable an interoperable MAC layer protocol for a twoslot TDMA control channel is provided in this document or referenced in other documents as appropriate. This document assumes the reader has a good working knowledge of the two-slot TDMA document suite identified in [9] and of trunked LMR systems as described in [8].