The present document specifies the procedures used at the radio interface (Reference Point Um, see GSM 04.02) for
Call Control (CC), Mobility Management (MM), Radio Resource (RR) management and Session Management (SM).
When the notations for further study or FS or FFS are present in the present document they mean that the
indicated text is not a normative portion of the present document.
These procedures are defined in terms of messages exchanged over the control channels of the radio interface. The
control channels are described in GSM 04.03.
The structured functions and procedures of this protocol and the relationship with other layers and entities are described
in general terms in GSM 04.07.