ZTE Corporation ZXG-BTS2 Benutzerhandbuch
ZXG10-BTS (V2.9) Technical Manual
32
Confidential and Proprietary Information of ZTE CORPORATION
F
I G U R E
1 2
C
I R C U I T
S
E R V I C E
P
R O T O C O L
H
I E R A R C H Y O F T H E
U
M
I
N T E R F A C E
CM
MM
RR
LAPDm
Sig.L1
Sig.L1
LAPDm
RR
MS
BTS
Um Interface
F
I G U R E
1 3
P
A C K E T
S
E R V I C E
P
R O T O C O L
S
T A C K
S
T R U C T U R E O F T H E
U
M
I
N T E R F A C E
MS
Um
Gb
BSS
SGSN
BSSGP
LLC
SNDCP
Network
Service
L1bis
relay
BSSGP
L1bis
RLC
MAC
GSM RF
relay
RLC
MAC
GSM RF
SNDCP
IP/X.25
application
LLC
Network
Service
On the Um interface, the circuit service protocols fall into three layers:
The first layer is the physical layer and also the underlying layer. It
consists of various channels and provides the basic wireless channels for
consists of various channels and provides the basic wireless channels for
upper-level message transmission.
The second layer is the data link layer and also the medium layer, with the
LapDm adopted. It comprises various data transmission structures and
controls data transmission.
controls data transmission.
The third layer (L3) is the highest layer. It comprises various messages
and programs and provides service control.L3 consists of three sub-layers:
and programs and provides service control.L3 consists of three sub-layers:
radio resource management (RR), mobility management (MM) and
connection management (CM).
connection management (CM).
The relevant protocols of the Um interface are as follows: