Introduction to UMTS USR7 FOR TRAINING PURPOSES ONLY

Objectives Version1Rev0
Objectives
On completion of this chapter the student should be able to:
• Name and state the purpose of the UMTS Domains
• Describe the architecture of a UMTS network.
• Describe the purpose of the major network components.
• Describe the options for evolution to future releases.
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
FOR T
RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
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Version1Rev0 UMTS Domains
UMTS Domains
Domain split
A basic architectural split is between the user equipment (terminals) and the infrastructure. This results
in two domains: the User Equipment Domain and the Infrastructure domain. User equipment is the
equipment used by the user to access UMTS services. User equipment has a radio interface to the
infrastructure. The infrastructure consists of the physical nodes which perform the various functions
required to terminate the radio interface and to support the telecommunication services requirements
of the users. The infrastructure is a shared resource that provides services to all authorised end users
within its coverage area. The reference point between the user equipment domain and the infrastructure
domain is termed the "Uu" reference point (UMTS radio interface).
User equipment Domain
This domain encompasses a variety of equipment types with different levels of functio
nality. These
equipment types are referred to as user equipment (terminals), and they may also be compatible with
oneormoreexistingaccess(fixed or radio) interfaces e.g. dual mode UMTS-GSM user equipment.
The user equipment may include a removable smart card that may be used in different u
ser equipment

types. The user equipment is further sub-divided in to the Mobile Equipment Domain (ME) and the
User Services Identity Module Domain (USIM). The reference point between the ME and the USIM is
termed the "Cu" reference point.
Mobile equipment Domain
The Mobile Equipment performs radio transmission and contai
ns applications. The mobile equipment
may be further sub-divided into several entities, e.g. the one which performs the radio transmission and
related functions, Mobile Termination, (MT), and the one which contains the end-to-end application or
(e.g. laptop connected to a mobile phone), Termin
al Equipment,(TE).
USIM Domain
The USIM contains data and procedures which u
nambiguously and securely identify itself. These
functions are typically embedded in a standalone smart card. This device is associated to a given user,
and as such allows to identify this user regardless of the ME he uses.
Infrastructure Domain
The Infrastructure domain is further split into the Access Network Domain, which is characterized
by being in direct contact with t
he User Equipment and the Core Network Domain. This split is
intended to simplify/assist the process of de-coupling access related functionality from non-access
related functionality and is in line with the modular principle adopted for the UMTS. The Access Network
Domain comprises roughly
the functions specific to the access technique, while the functions in the Core
network domain may potentially be used with information flows using any access technique. This split
allows for different approaches for the Core Network Domain, each approach specifying distinct types
of Core Networks which c
an be connected to the Access Network Domain, as well as different access
techniques, each type of Access Network connected to th Core Network Domain. The reference point
between the access network domain and the core network domain is termed the "lu" reference point.
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FOR TRAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
© 2009 Motorola, Inc.
USR7
UMTS Domains Version1Rev0
UMTS Domains
Home
Network
Domain
Transit
Network
Domain
Serving
Network
Domain
Core
Network
Domain
Access
Network
Domain
Mobile
Equipment
Domain
USIM
Domain
Infrastructure
Domain
User Equipment
Domain
Iu [Yu]Uu

[Zu]
Cu
SIM
CARD
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
FOR T
RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
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Version1Rev0 UMTS Domains
UMTS Domains
Access Network D om ain
The Access Network Domain consists of the physical entities which manage the resources of the access
network and provides the user with a mechanism to access the core network domain.
Core Network Domain
The Core Network Domain consists of the physical entities which provide support for the network
features and telecommunication services. The support provided includes functionality such as the
management of user location information, control of network features and services, the transfer
(switching and transmission) mechanisms for signalling and for user generated information.
The core network domain is sub-divided into the ServingNetwork Domain,theHome Network Domain
and the Transit Network Domain. The reference point between the serving network domain and the
home network domain is termed the [Zu] reference point. The reference point between the serving
network domain and the transit network domain is termed the [Yu] reference point.
Serving Network Domain
The serving network domain is the part of the core network domain to w
hich the access network domain
that provides the user's access is connected. It represents the core network functions that are local to the
user's access point and thus their location changes when the user moves. The serving network domain
is responsible for routing calls and transport user data/info

rmation from source to destination. It has the
ability to interact with the home domain to cater for user specific data/services and with the transit domain
for non-user specific data/services purposes.
Home Network Domain
The home network domain represents the core network functions that are conducted at a permanent
location regardless of the location of the user
's access point. The USIM is related by subscription to the
home network domain. The home network domain therefore contains at least permanently user specific
data and is responsible for management of subscription information. It may also handle home specific
services, potentially not offered by t
he serving network domain.
Transit Network Domain
The transit network domain is the c
ore network part located on the communication path between the
serving network domain and the remote party. If, for a given call, the remote party is located inside the
same network as the originating UE, then no particular instance of the transit domain is activated.
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UMTS Domains Version1Rev0
UMTS Domains
Home
Network
Domain
Transit
Network
Domain
Serving
Network

Domain
Core
Network
Domain
Access
Network
Domain
Mobile
Equipment
Domain
USIM
Domain
Infrastructure
Domain
User Equipment
Domain
Iu [Yu]Uu
[Zu]
Cu
SIM
CARD
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
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RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
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USR7
Version1Rev0 UMTSArchitecture-Release1999
UMTS Architecture - Release 1999
The diagram opposite illustrates the basic configuration of a Public Land Mobile Network (PLMN)

supporting UMTS and GSM/GPRS. This architecture is as defined in Release 1999 of the 3GPP (Dec
02) specifications (TS23.002)
The Core Network (CN) Entities
The CN is constituted of a Circuit Switched (CS) domain and a Packet Switched (PS) domain. These
two domains differ by the way they support user traffic, as explained below. These two domains are
overlapping, i.e. they contain some common entities. A PLMN can implement only one domain or both
domains.
CS Domain
The CS domain refers to the set of all the CN entities offering "CS type of connection" for user trafficas
well as all the entities supporting the related signalling. A "CS type of connection" is a connection for
which dedicated network resources are allocated at the connection establishment and
released at the
connection release. The entities specific to the CS domain are:
• MSC - The Mobile-services Switching Centre
• GMSC - Gateway Mobile Service Switching Centre
• VLR - Visitor Location Register
PS Domain
ThePSdomainreferstothesetofalltheCNentitiesoffering"PS
type of connection" for user traffic
as well as all the entities supporting the related signalling. A "PS type of connection" transports the
user information using autonomous concatenation of bits called packets: each packet can be routed
independently from the previous one. The entities specifict
othePSdomainaretheGPRSspecific
entities, i.e.
• SGSN - Serving GPRS Support Node
• GGSN - Gateway GPRS Support Node
EntitiesCommontotheCSandPSdomains
The following entities are common provide common functions to the CS and PS Domains:
• HLR-TheHomeLocationRegister
• AUC - Authentication Centre

• EIR - Equipment Identity Register
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UMTS Architecture - Release 1999 Version 1 Rev 0
UMTS Architecture - Release 1999
GMSC
GGSN
AuC
HLR
EIR
SGSN
VLR
MSC
VLR
MSC
SIM
ME
USIM
Um
Um
CN
BSC
BTS BTS
BSC
BTS BTS
RNC
Node B
Node B

RNC
Node B
Node B
H
Gc
Gr
D
C
Gi
Gs
GfF
G
E
Gp
Gn
PSTN PSTN
Abis
Gb
BS
S
Abis
lublub
RNS
RNSBSS
SIM-ME I/f
or
MS
Cu
Uu
IuPSIuCS

IuPS
IuCS
A
Iur
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Version1Rev0 UMTSArchitecture-Release1999
UMTS Architecture - Release 1999
The Access Network (AN) Entities
Two different types of access network are used by the CN: the Base Station System (BSS) and the
Radio Network System (RNS). The BSS offers a Time Division Multiple Access(TDMA) based
technology to access the Mobile Station whereas the RNS offers a Wideband-Code Division Multiple
Access (W-CDMA) based technology. The MSC (resp. SGSN) can connect to one of these Access
Networktypeortobothofthem.
The Base Station System (BSS)
The Base Station System (BSS) is the system of base station equipments (transceivers, controllers,
etc ) which is viewed by the MSC through a single A-interface as being the entity responsible for
communicating with Mobile Stations in a certain area. Similarly, in PLMNs supporting GPRS, the BSS
is viewed by the SGSN through a single Gb interface. The functionality for the A interface is described
in GSM 08.02 and for the Gb interface in TS 23.060. The radio equipment of a BSS may support one or
more cells. A BSS may consist of one or more base stations. Where an Abis-interface is im
plemented,
the BSS consists of one Base Station Controller (BSC) and one or more Base Transceiver Station
(BTS).
The Radio Network System (RNS)
The Radio Network System (RNS) is the system of base station equipments (transceivers, controllers,

etc ) which is viewed by the MSC through a single Iu-interface as being the entity responsible for
communicating with Mobile Stations in a certain area. Similarl
y, in PLMNs supporting GPRS, the RNS
is viewed by the SGSN through a single Iu-PS interface. The functionality for the Iu-CS interface is
described in TS 25.410 and for the Iu-PS interface in TS 23.060. The radio equipment of a RNS may
support one or more cells. A RNS may consist of one or more base
stations. The RNS consists of one
Radio Network Controller (RNC) and one or more Node B.
TheMobileStation(MS)
The mobile station consists of the physical equipment used by a PLMN subscriber; it comprises the
Mobile Equipment (ME) and the Subscriber Identity Module (SIM), called User Services Identity
Module (USIM) for Release 99 and following re
leases. The ME comprises the Mobile Termination
(MT) which, depending on the application and services, may support various combinations of Terminal
Adapter (TA) and Terminal Equipment (TE) functional groups. These functional groups are described
in GSM 04.02.
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USR7
UMTS Architecture - Release 1999 Version 1 Rev 0
UMTS Architecture - Release 1999
GMSC
GGSN
AuC
HLR
EIR
SGSN
VLR
MSC

VLR
MSC
SIM
ME
USIM
Um
Um
CN
BSC
BTS BTS
BSC
BTS BTS
RNC
Node B
Node B
RNC
Node B
Node B
H
Gc
Gr
D
C
Gi
Gs
GfF
G
E
Gp
Gn

PSTN PSTN
Abis
Gb
BS
S
Abis
lublub
RNS
RNSBSS
SIM-ME I/f
or
MS
Cu
Uu
IuPSIuCS
IuPS
IuCS
A
Iur
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
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RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
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Version 1 Rev 0 UMTS Network - Release 1999
UMTS Network - Release 1999
The diagram opposite shows a simplified schematic of a Release 1999 UMTS Network. It illustrates only
those entities associated with providing a UMTS service (i.e. excludes any entities specifically associated
with GSM/GPRS)

Entities of the CN-CS Domain
The Mobile Services Switching Centre (MSC)
The Mobile-services Switching Centre (MSC) constitutes the interface between the radio system and
the fixed networks. The MSC performs all necessary functions in order to handle the circuit switched
services to and from the mobile stations. In order to obtain radio coverage of a given geographical area,
a number of base stations are normally required; i.e. each MSC would thus have to interface several
base stations. In addition several MSCs may be required to cover a country. The Mobile-services
Switching Centre is an exchange which performs all the switching and signalling functions for mobile
stations located in a geographical area designated as the MSC area. The main difference
between a
MSC and an exchange in a fixed network is that the MSC has to take into account the impact of the
allocation of radio resources and the mobile nature of the subscribers and has to perform procedures
required for the location registration (see TS 23.012) and procedures required fo
r handovers (see TS
23.009).
The Gateway MSC (GMSC)
If a network delivering a call to the PLMN cannot interrogate the H
LR, the call is routed to an MSC. This
MSC will interrogate the appropriate HLR and then route the call to the MSC where the mobile station
is located. The MSC which performs the routing function to the actual location of the MS is called the
Gateway MSC (GMSC). The acceptance of an interrogation to an H
LR is the decision of the operator.
The choice of which MSCs can act as Gateway MSCs is for the operator to decide (i.e. all MSCs or
some designated MSCs).
The Visitor Location Register (VLR)
A mobile station roaming in an MSC area is controlled by the Visitor Location Register (VLR) in charge
of this area. When a Mobile Station (MS) enters a new location area it starts a registration procedure.
The MSC in charge of that area notices this regi
stration and transfers to the VLR the identity of the
location area where the MS is situated. If this MS is not yet registered, the VLR and the HLR exchange

information to allow the proper handling of calls involving the MS. A VLR may be in charge of one or
several MSC areas. The VLR contains al
so the information needed to handle the calls set-up or received
by the MSs registered in its database. The following elements are included:
• The International Mobile Subscriber Identity (IMSI);
• The Mobile Station International
ISDN number (MSISDN);
• The Mobile Station Roaming Number (MSRN), see TS 23.003 for allocation principles;
• The Temporary Mobile Station Identity (TMSI), if applicable;
• The Local Mobile Station Id
entity (LMSI),ifused;
• The location area where the mobile station has been registered;
• The last known location and the initial location of the MS.
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UMTS Network - Release 1999 Version 1 Rev 0
UMTS Network - Release 1999
Node B
Node B
Iub Iub
RNC
UTRAN
Node B
Node B
Iub Iub
RNC
HLR
VLR

AuC
GMSC
MSC
GGSN
SGSN
CN-CS
CN-PS
CN Domain
Iu-CS Iu-PS
PSTN PDN
OMC-T
(Transport)
OMC-U
(UTRAN)
Iur
Uu
User Equipment
RNS
RNS
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
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RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
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Version 1 Rev 0 UMTS Network - Release 1999
UMTS Network - Release 1 999
Entities Common to the CS and PS Dom ains
The Home Location Register (HLR)
This functional entity is a database in charge of the management of mobile subscribers. A PLMN may

contain one or several HLRs: it depends on the number of mobile subscribers, on the capacity of the
equipment and on the organisation of the network. The following kinds of information are stored there:
• Subscription information.
• Location information enabling the charging and routing of calls towards the MSC where the MS
is registered (e.g. the MS Roaming Number, the VLR Number, the MSC Number, the Local MS
Identity).
• If GPRS is supported, location information enabling the charging and routing of messages in the
SGSN where the MS is currently registered (e.g. the SGSN Number).
• The types of identity are attached to each mobile (e.g. International Mobile Station Identity
(IMSI), one or more Mobile Station International ISDN Number(s) (MSISDN),ifGPRSis
supported zero or more Packet Data Protocol (PDP) address(es)).
The Authentication Centre (AuC)
The Authentication Centre (AuC) is an entity which stores data for each mobile subscriber to allow
the International Mobile Subscriber Identity (IMSI) to be authenticated and to allow communication
over the radio path between the mobile station and the network to
be ciphered. The AuC transmits the
data needed for authentication and ciphering via the HLR to the VLR, MSC and SGSN which needs
to authenticate a mobile station. The Authentication Centre (AuC) is associated with an HLR, and
stores an identity key for each mobile subscriber registere
d with the associated HLR. This key is used
to generate:
• Data which are used to authenticate the International Mobile Subscriber Identity (IMSI).
• A key used to cipher communication over the radio
path between the mobile station and the network.
The Equipment Identity Register (EIR)
The Equipment Identity Register (EIR) in the GSM system is the logical entity which is responsible for
storing in the network the International Mobile Equipment Identities (IMEIs), used in the GSM system.
The equipment is classified as "white l
isted", "grey listed", "black listed" or it may be unknown as specified
in TS 22.016 and TS 29.002.

This functional entity contains one or several databases which store(s) the IMEIs used in the GSM
system. An EIR shall as a minimum co
ntain a "white list" (Equipment classified as "white listed"). See
also TS 22.016 on IMEI.
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UMTS Network - Release 1999 Version 1 Rev 0
UMTS Network - Release 1999
Node B
Node B
Iub Iub
RNC
UTRAN
Node B
Node B
Iub Iub
RNC
HLR
VLR
AuC
GMSC
MSC
GGSN
SGSN
CN-CS
CN-PS
CN Domain
Iu-CS Iu-PS

PSTN PDN
OMC-T
(Transport)
OMC-U
(UTRAN)
Iur
Uu
User Equipment
RNS
RNS
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
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Version1Rev0 UMTS Network R4
UMTS Network R4
In R4 the separation of the switching and call control functions within the core network is commonly
referred to as a softswitch architecture. The call control component, i.e. the MSC server, is the softswitch
in this case. This separation of functions makes it easier to scale the network as the traffic demand
increases. If the network planners require more switching capacity they can add MGWs; if they require
more call control capacity they then add more MSC servers. This is a clear distinction from the UMTS
Release 99 and GSM networks, in which the call control and switching functions are all carried out within
the MSC and gateway MSC (GMSC).
Media Gateways (MGWs)
This translates media traffic between different types of network. Functionality carried out by the MGW
includes:
• Termination of bearer channels from the circuit switched and packet switched networks;
• Echo cancellation for circuit switched circuits;

• Translation of media from one CODEC form to another,
Each MGW is controlled by one or more MSC servers.
MSC Server
This performs functions such as call control for mobile-originated and mobile-terminated calls, and
mobility management in terms of maintenance of the registry of mo
biles within its area of control. The
MSC server integrates with the Visitor Location Register (VLR) component, which holds location
information as well as CAMEL (customized applications for mobile network enhanced logic) data for
subscribers. Functions carried out by the MSC server include
:
• Controlling the registration of mobiles to provide mobili
ty management;
• Providing authentication functions;
• Routing mobile-originated calls to their destination;
• Routing mobile-terminated calls by using pagin
g to individual mobiles.
The MSC server terminates signalling from the
mobile network over the Iu interface to the RNC. It also
controls the establishment of bearers across its core by the use of MGWs under its control.
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UMTS Network R4 Version1Rev0
UMTS Network R4
NODEB
BTS
RNC
BSC
GERAN

UTRAN
MGW MGW
MSC Server
CN CS Domain
SGSN GGSN
CN PS Domain
HLR/VLR/EIR
Data Network
PSTN/ISDN
Um
Uu
Network Management (NMS)
IuPS
IuCS
A
Gb
ABIS
Iub
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
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Version1Rev0 UMTSNetworkRelease5
UMTS Network Release 5
Release 5 (R5) builds on the partial implementation of IP packet switching within the core network, to
move to an all-IP architecture. In this release, packets can be moved end-to-end using IP transport with
an enhanced GPRS network connected to an IP multimedia subsystem (IMS). The GPRS backbone
for R5 must be able to provide similar levels and classifications of QoS usually associated with ATM

networks. This is to allow for the delivery of time-sensitive traffic such as voice and multimedia. As well
as enhancements to the core network, the RAN also migrates from ATM to IP. Even though the vision
for R5 is for a total IP solution, the operator may well still use ATM as a transport solution for some parts
of the network. This is possible because all UMTS releases must provide backward compatibility with
earlier releases.
Notice that in the R5 network, the CS domain can be dispensed with since the services associated
with it, such as transfer of voice traffic, can be carried over the GPRS and IMS networks using IP QoS
mechanisms. That given, many operators may still be using the R4 CS domain as well as the R5 IMS
architecture. This allows for a gradual migration to an all-IP architecture with the minimal disruption
to service. Some voice calls may be handled using the CS domain and some, for example video call
services, via the IMS.
IP MULTIMEDIA SUBSYSTEM (IMS)
R5 introduces a new network domain called the IP Multimedia Subsystem (IMS). This is an IP network
domain designed to provide appropriate support for real-time multimedia servi
ces.
The UE communicates with the IMS using GPRS, with the IMS being directly connected to the GGSN.
The IMS provides services to mobile users such as:
• Real-time communication using voice, video or multimedia messaging (i.e. voice and video
telephony);
• Audioconferencing and videoconferencing;
• Content delivery services such as video, audio or multimedia download;
• Content streaming services such as video, audio or
multimedia streaming (e.g. using video on
demand server);
• Multimedia Messaging Service (MMS).
Each operator’s IMS can be connected to other op
erators’ IMSs, allowing multimedia services between
users on different networks. Connections to the public Internet allow MMS messaging as well as voice
over IP (VoIP) and video telephony between mobile and fixed-line users. Finally, the interface to the ISDN
(or other circuit switched networks) allow

s VoIP calls to be connected through to conventional fixed-line
and mobile users, e.g. GSM. Connections between the IMS and other IP networks are controlled by
firewalls to protect against hacking. The interface between the IMS and the CS network is controlled by
the softswitch and MGW components. W
ithin the operator’s network the IMS is connected to the Home
Subscriber Server (HSS) to allow for subscriber authentication, authorization and mobility management.
For R5 and beyond, the IMS can be used to provide transport for all of the operator’s services, including
conventional voice calls.
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UMTS Network Release 5 Version 1 Rev 0
UMTS Network Release 5
NODEB
BTS
RNC
BSC
GERAN
UTRAN
SGSN GGSN
CN PS Domain
HSS
IMS
IP Multimedia
PSTN/ISDN
Um
Uu
Network Management (NMS)
ATM/IP

IuPS
Gb
ABIS
Iub
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Version 1 Rev 0 UMTS Terrestrial Radio Access Network (UTRAN)
UMTS Terrestrial Radio Access Network (UTRAN)
The UTRAN consists of a set of Radio Network Subsystems (RNSs) connected to the Core Network
through the IuCS and IuPS. A RNS consists of a Radio Network Controller (RNC) and one or more
Node Bs. A Node B is connected to the RNC through the Iub interface. A Node B can support FDD mode,
TDD mode or dual-mode operation. The RNC is responsible for the Handover decisions that require
signalling to the UE. An RNC may include a combining/splitting function to support combination/splitting
of information streams.
Inside the UTRAN, the RNCs of the Radio Network Subsystems can be interconnected together through
the Iur. Iu(s) and Iur are logical interfaces. Iur can be conveyed over direct physical connection between
RNCs or virtual networks using any suitable transport network.
UTRAN Functions
The following is a list of the functions performed by the UTRAN sub-systems. These functions will be
discussed in further detail in later chapters.
Functions related to overall system access control
• Admission Control
• Congestion Control
• System information broadcasting
Radio channel ciphering and deciphering
Functions related to mobility

• Handover
• SRNS Relocation
Functions related to radio resource management and control
• Radio resource configuration and operation
• Radio environment survey
• combining/splitting control
• Radio bearer connection set-up and release (Radio Bearer Control)
• Allocation and deallocation of Radio Bearers
• Radio protocols function
• RF power control
• RF power setting
• Radio channel coding/decod
ing
• Channel coding control
• Initial (random) access detection and handling
• CN Distribution function
for Non Access Stratum messages
Functions related to br
oadcast and multicast services
NOTE: Only Broadcast is applicable for Release 1999.
• Broadcast/Multicast Information Distribution
• Broadcast/Multic
ast Flow Control
• CBS Status Reporting
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UMTS Terrestrial Radio Access Network (UTRAN) Version 1 Rev 0
UMTS Terrestrial Radio Access Network (UTRAN)

c
Node B Node B
Iub Iub
RNC
Node B Node B
Iub Iub
RNC
Core Network
Iu Iu
Iur
RNS
RNS
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Version 1 Rev 0 Radio network Controller (RNC)
Radio network Controller (RNC)
A Radio Network Controller (RNC) is a network component within the PLMN with the functions to
support one or more Node B, Cell and/or User Equipment.
Typically one RNC can support up to 300 Node Bs, which in turn can provide resources for up to 6 cells.
However, it should be noted that the ultimate limiting factor in planning the number of RNCs required
withinaPLMNwillbethetraffic capacity that the RNC can support. Typical values will start at around
1000 Erlang, rising to 10,000 Erlang as networks mature.
A Radio Network Controller (RNC) can be considered to operate in one or more of the following roles:
• Controlling Radio Network Controller (CRNC)
• Serving Radio Network Controller (SRNC)
• Drift Radio Network Controller (DRNC)

Controlling Radio Network Controller (CRNC)
Controlling RNC is a role an RNC can take with respect to a specific set of Node B's. There i
s only one
Controlling RNC for any Node B. The Controlling RNC has the overall control of the logical resources of
its node B's.
The main functions of a CRNC are:
• Control of the Radio Resources for the Node-B it controls.
• Provision of Services to the Node-B that it controls.
• Load and Congestion Control
• Admission Control
• Code allocation for new radio links
2-22 CP13: Introduction to UMTS USR7
FOR TRAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
© 2009 Motorola, Inc.
USR7
Radio network Controller (RNC) Version 1 Rev 0
Radio network Controller (RNC)
UTRAN CRNC Functions
Controlling of the Radio Resources
Provision of Services to the Node-B
Load and Congestion Control
Admission Control
Code Allocation for new Radio Links
·
·
·
·
·
Iu
lur

Iu
C-RNCC-RNC
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
FOR T
RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
2-23
USR7
Version 1 Rev 0 Radio network Controller (RNC)
Radio network Controller (RNC)
Serving Radio Network Controller (SRNC)
A Serving RNC is the RNC located within a Serving RNS (SRNS).SRNSisaroleanRNScantakewith
respect to a specific connection between an UE and UTRAN.
There is one Serving RNS for each UE that has a connection to UTRAN.
The Serving RNS is in charge of the radio connection between a UE and the UTRAN.
The Serving RNS terminates the Iu for this UE.
The main functions of an SRNC are:
• Termination of the Radio Resource Control Signalling between the RNC and the UE.
• L2 Processing (PDCP, RLC, MAC).
• Radio Resource Control operations.
• Mapping of Iu Bearer Parameters onto Transport Channels Parameters.
• Hand-over decisions.
• Outer loop power control.
• Macro-Diversity combining and splitting.
2-24 CP13: Introduction to UMTS USR7
FOR TRAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
© 2009 Motorola, Inc.
USR7
Radio network Controller (RNC) Version 1 Rev 0
Radio network Controller (RNC)

UTRAN SRNC Functions
Termination of the Radio Resource Control Signalling
between the RNC and the UE
L2 Processing (PDCP, RLC, MAC)
Radio Resource Control Operations
Mapping of Bearer Parameters onto Transport Channel Parameters
·
·
·
·
Hand-Over Decisions
·
S-RNC
Outer Loop Power Control
·
Macro-diversity Combining and Splitting
·
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
FOR T
RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
2-25
USR7
Version 1 Rev 0 Radio network Controller (RNC)
Radio network Controller (RNC)
Drift Radio Network Controller (DRNC)
A Drift RNC is located within a Drift RNS. DRNS is role that an RNS can take with respect to a specific
connection between a UE and UTRAN.
A DRNS is any RNS that supports the Serving RNS by providing radio resources via the cell(s) it controls,
to provide additional radio bearer services for a specific connection between a UE and UTRAN.

There may be zero, one or more DRNSs associated with a specific connection between a UE and
UTRAN.
The main functions of a DRNC are:
• Macro-diversity combining and splitting.
• No L2 processing, i.e. no re-transmissions, acknowledgements or negative acknowledgements.
• Transparent routing of data on the Iub and Iur Interfaces, except when Common or shared channels
are used.
2-26 CP13: Introduction to UMTS USR7
FOR TRAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
© 2009 Motorola, Inc.
USR7
Radio network Controller (RNC) Version 1 Rev 0
Radio network Controller (RNC)
UTRAN DRNC Functions
Macro-diversity Combining and Splitting
No L2 Processing
Transparent Routing except for Common/Shared Channels
·
·
·
D-RNC
S-RNC
© 2009 Motorola, Inc.
CP13: Introduction to UMTS USR7
FOR T
RAINING PURPOSES ONLY - THIS MANUAL WILL NOT BE UPDATED
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USR7