User's Manual

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DESCRIPTION 21 ( 25 )
ERA/RGN/PD Jennie Bergström 5/1551-HRB 105 102/1 Uen
ERA/RKF/TU Carl Helander 2003-01-28 C
Prepared (also subject responsible if other) No
Approved Checked Date Rev Reference
E
UE
B 00 00559
Uu
GUI
VMI
Mub
Iub
RNC
RBS
Figure 5 External Interfaces
7.1 lub Interface
The Iub interface is the standardized interface between the RBS and the RNC.
The Iub is divided into several protocol layers:
• Physical layer (L1)
• ATM and ATM adaptation layers (L2)
• Network layer (L3) for frame handling
The L3 protocol for the RNC plane is called NBAP. The L2 and L3 part of
air interface channels RACH, FACH, PCH and DCH terminate in the RNC.
From an RBS perspective, the different air interface channels are all treated
as transparent user plane channels.
7.2 Uu Interface
The Uu interface is the radio interface between RBS and the UE. The radio
interface is divided into three protocol layers:
• Physical layer (L1)
• Data link layer (L2)
• Network layer (L3)