UMTS (Universal Mobile Telecommuniations System)
<伊落丹> illidan.modeler [at] gmail.com
Northern Capital, Republic of Pandaren
System Architecture
UTRAN
UTRAN, short for
UMTS
Terrestrial
Radio
Access
Network, is a collective term for the
Node B's and
Radio Network Controllers which make up the
UMTS radio access network.
The UTRAN allows connectivity between the
UE (user equipment) and the
core network. The UTRAN contains the base stations, which are called
Node Bs, and
Radio Network Controllers
(RNC). The RNC provides control functionalities for one or more Node
Bs. A Node B and an RNC can be the same device, although typical
implementations have a separate RNC located in a central office serving
multiple Node Bs.
The RNC and its corresponding Node Bs are called the
Radio Network Subsystem (RNS). There can be more than one RNS present in an UTRAN.
Radio Resource Control
RRC handles the
control plane signalling of Layer 3 between the
UEs and
UTRAN.
The major part of the control signalling between UE and UTRAN is RRC messages. RRC messages carry all parameters required to set up, modify and release layer 2 and layer 1 protocol entities. RRC messages also carry in their payload all higher layer signalling (mobility management (MM), connection management (CM), session management (SM), etc.). The mobility of user equipment in the connected mode is controlled by RRC signalling (measurements, handovers, cell updates, etc.).
Literature
1. [web] "UMTS Terrestrial Radio Access Network."
Wikipedia, The Free Encyclopedia. 20 Apr 2009, 09:51 UTC. 21 Apr 2009 <
http://en.wikipedia.org/w/index.php?title=UMTS_Terrestrial_Radio_Access_Network&oldid=284982903>.
2. [book] [Holma 2007] Section 7.8 "The Radio Resource Control Protocol"
3. [web] "Radio Resource Control."
Wikipedia, The Free Encyclopedia. 12 Feb 2009, 04:30 UTC. 5 May 2009 <
http://en.wikipedia.org/w/index.php?title=Radio_Resource_Control&oldid=270157640>.