Figure below shows the user data processing path at the
BS and MS. As shown in the figure, the user data traverses the path from
network layer to physical layer and vice versa. In the transmitter side, a
network layer packet is processed by the convergence sub-layer, the ARQ
function (if enabled), the fragmentation/packing function, and the MAC PDU
formation function, to form the MAC PDU to be sent to the physical layer for
processing. In the receiver side, a physical layer SDU is processed by MAC PDU
formation function, the fragmentation/packing function, the ARQ function (if
enabled), and the convergence sub-layer function, to form the network layer
packets. The control primitives between the MAC CPS functions and between the
MAC CPS and PHY that are related to the processing of user traffic data are
also shown below
Signal flow graph in data- and control-planes
The control-plane signaling and processing
flow graph at the BS and the MS. In the
transmitter side, the flow of control primitives from control-plane
functions to data-plane functions and processing of control-plane signals
by data-plane functions in order to construct MAC management messages
and MAC header/sub-headers, to be transmitted over the air interface, are
illustrated. In the receiver side, the arrows show the processing
of the MAC control messages through data-plane functions and the
reception of the corresponding control-plane signals by control-plane
functions. The dotted arrows show the control primitives between MAC
CPS functions and between MAC CPS and physical layer functions that are
related to the processing of control-plane signaling. The
control primitives to/from M-SAP/C-SAP define the network related
functionalities, such as inter-BS interference management, inter/intra RAT
mobility management, etc., as well as management-related functionalities, such
as location management, system configuration, etc.
