The MS and BS Interface

The MAC management PDUs that are exchanged over the primary management connectioniii can trigger, or are triggered by, primitives that are exchanged over either the C-SAP or the M-SAP, depending on the particular management or control operation. The messages that are exchanged over the secondary management connection can trigger or are triggered by primitives that are exchanged over the M-SAP. This interface is a set of SAP between an IEEE 802.16 entity and NCMS as shown in Figure below. 

It consists of two parts: the M-SAP is used for delay-tolerant management-plane primitives; and the C-SAP is used for delay-sensitive control-plane primitives that support handovers, security context management, radio resource management, and low power operations such as idle mode and paging functions.