WR_BT06_E1_1Interface protocol and signaling flow

ZTE University

TD&W&PCS BSS Course Team

Objectives

At the end of this course, you will be able to:Ø Master Network interfaces protocol

Ø Master signaling flow

Content

Network InterfacesUE State transition

Signaling flow

UTRAN Architecture

Network Interfaces

Iu Interface

Node B

RNC

RNC

CSDomain

PSDomain

BCDomain

Node B

Node B

Node B

UTRAN Core Network (CN)

“Iu-CS”

“Iu-PS”

“Iu-BC”

Iu Interface

Network Interfaces

Iu-CS Interface Stack Structure

Network Interfaces

Iu-CS Interface Stack Structure

n RANAP：RAB management

Iu signaling management

data throughput report

Paging

Security

location report

n SCCP ：Support connection and connectionless

service. Used to realize routing function.

Iu-CS Interface Stack Structure

n M3UA：Support for the transport of MTP3-User messages.

Native management functions (Error report)

Interworking with MTP3 network management functions

Support for the Management of SCTP associations

Address mapping

n SCTP：Establishment and release of association

User data segmentation

Verification and avoidance of congestion

Data block binding

Packet validity verification

Path management

Iu-CS Interface Stack Structure

RTP( Real time transport protocol)：

Provide time information and implement stream synchronization for P to

P(M) multimedia data streams service over internet,.

Established on UDP,TCP or ATM.

n RTCP：

Managing transmission quality

Exchange control message between current applications

Iu-PS Interface Stack Structure

Network Interfaces

Iu interface Functions

n RAB management� RAB setup, modification and release� mapping of RAB characteristics to the Uu bearer� mapping of RAB characteristics to the Iu transmission bearer� RAB queuing, preemption and priority

n Iu radio resource management� radio resource acceptance control

n Iu connection management� Iu signaling connection management

n Iu-UP (RNL) management� Iu-UP frame protocol mode selection and protocol initialization

n Mobility management (IMSI ATTACH/DETACH, location update etc)n Security management (Authentication and encryption )n Service and network accessn Paging coordination

Network Interfaces

Iur Interface Stack Structure

Network Interfaces

Iur interface Functions

Iur interface has the following functions:

n Inter-RNC mobility management� SRNC relocation, inter-RNC cell and UTRAN registration area update,

inter-RNC paging, and protocol error report.

n Dedicated channel data transmission� used to transmit dedicated channel data between two RNCs.

n Common channel data transmission� setup and release of the transmission connection needed in common

channel data stream transmission of the Iur interface,

n Global resource management� transmission of inter-RNC cell measurement information.� transmission of inter-RNC Node B timing information.

Network Interfaces

Iub Interface Stack Structure

Network Interfaces

Iub interface Functions

n Management of the Iub interface transmission resources.

n Logic operation maintenance of Node B, including:

� the cell configuration management

� radio network performance measurement

� common transmission channel management

� radio resource management

n Transmission of application-related operation & maintenance data.

n System information management.

n Channel traffic management.

n Timing and synchronization management, including:

� Node B synchronization

� transmission channel synchronization between the RNC and Node B

Network Interfaces

Uu Interface Stack Structure

L3

cont

r o lcont

rol

cont

rol

cont

rol

LogicalChannels

TransportChannels

C-planesignalling

U-planeinformation

PHY

L2/MAC

L1

RLC

DC

Nt

GC

L2/RLC

MAC

RLCRLC

RLCRLC

RLCRLCRLC

Duplicationavoidance

UuSboundary

BMC L2/ BMC

control

PDCPPDCP L2/PDCP

DC

Nt

GC

RadioBearers

RRC

Network Interfaces

Uu Interface Stack Structure(1)

n Physical Layer Protocol� provides the MAC sublayer with transmission channel services.

n MAC Protocol (Media Access Control)� provides the RLC sublayer with logic channel services. (Data correction and

flow control)n RLC Protocol (Radio Link Control)

� on the control plane, provides the RRC sublayer with signaling radio bearerservices.

� on the user plane, provides service radio bearer services together with thePDCP sublayer.

n PDCP (Packet data convergence protocol)� adapt different types of network layer protocols to the radio interface.� only exists in the packet domain

n BMC (Broadcast main control)� transfer broadcast and multicast information over the radio interface.

Network Interfaces

Uu Interface Stack Structure(2)

n RRC (Radio resource control)� Provide services for the non-access layer, for example, transmitting

messages like call control, session management and mobilitymanagement at the control interface.

� Setup, maintenance and release of an RRC connection between UEand UTRAN.

� Setup, reconfiguration and release of radio bearer.� Distribution, reconfiguration and release of radio resources used in the

RRC connection.� RRC connection’s mobility function management.� Request for QoS control.� UE measurement report and report control.� Outer loop power control, ciphering control, paging.� Initial cell selection and reselection in the idle mode.

Network Interfaces

Radio Network Control-Plane protocol

RNC

CN

Node B

UE RNC

RANAPRNSAP

NBAP

RRC

NBAP：Node B Application Part

RANAP: Radio Access Network Application Part

RNSAP: Radio Network Subsystem Application Part

RRC: Radio Resource Control

Network Interfaces

NBAP

L1 L1

MAC

RLC

RRC

MM/GMM

CC SM

NBAP

Transport Layer

TransportLayer

TransportLayer

MAC

RLCRRC RANAP RANAP

MM/GMM

CC SM

Uu

UE Node B RNC CN

Iub Iu

…Transport

Layer

UTRAN Control Plane Protocol Stack

Network Interfaces

L1

MAC

RLC

PDCP

TransportLayer

TransportLayer

Iu UP

Uu

UE Node B RNC CN

Iub Iu

L1 FP FPTransport Layer

MAC

RLC

PDCP

Iu UPUser data

TransportLayer

UTRAN User Plane Protocol Stack

Network Interfaces

Content

ATM Basics

Network Interfaces

UE State transitionSignaling flow

UE Working Modes

n There are two basic working modes:

� Idle

� UE stands by without any service. There’s no connection

between UE and UTRAN. UTRAN don’t have any information

about UE. Through NAS identity( IMSI/ TMSI) to identify UE.

� Connected

� UE transferred to the connected mode after accomplishing

RRC Connection Setup.

� UE has 4 states under the connected mode:►Cell-DCH, Cell-FACH, Cell-PCH, URA-PCH

UE State transition

UE States Under the Connected Mode

n Cell-DCH

� UE is activated, and in service using its dedicated channels.

� There are dedicated channels in both uplink and downlink.

� UTRAN knows exactly which cell the UE is in.

n Cell-FACH

� UE is activated, but without too much data to transmit, so

there’s no need to assign dedicated channels to it.

� Downlink data transmitted in FACH, while uplink in RACH.

� UTRAN knows exactly which cell the UE is in.

UE State transition

n Cell-PCH� There is no data transmitted in both uplink and downlink.

� UE needs to listen to PICH for paging information.

� UE works in discrete receiving, which saves the power effectively.

� UTRAN knows exactly which cell the UE is in.

� UE needs to do cell update procedure when it passes cells.

n URA-PCH� There is no data transmitted in both uplink and downlink.

� UE needs to listen to PICH for paging information and receive discretely.

� UTRAN only knows which URA (UTRAN Registration Area) UE exists.

� UE updates its location information only when its URA changes, whichfurther reduces the signaling saves resource.

UE States Under the Connected Mode

UE State transition

RRC State Transition (I)

n After RRC Connection Setup, UE willtransit to CELL_FACH or CELL_DCH.

n CN indicates UE using dedicated channel(CELL_DCH) or common channel(CELL_FACH) according to the servicerequest.

n If there is no service right now, UE will beindicated into PCH mode or release RRCconnection back to IDLE mode.

URA_PCH

CELL_DCH CELL_FACH

CELL_PCH

IDLE

DEAD

IDLE

DEAD

CELL_DCH CELL_FACH

IDLE

Sketch of RRC State Transition

—— Transit from IDLE Mode

UE State transition

URA_PCH

CELL_DCH

CELL_PCH

IDLE

DEAD

IDLE

DEAD

CELL_FACH

IDLE

n UE do not occupy dedicated channels

In the mode of CELL_FACH.

n UE receives downlink data through

FACH(S-CCPCH).

n UE transmits uplink data through

RACH(PRACH).

——Transit from CELL_FACH Mode

RRC State Transition (II)

Sketch of RRC State Transition

UE State transition

URA_PCH

CELL_DCH CELL_FACH

CELL_PCH

IDLE

DEAD

IDLE

DEAD

CELL_DCH

IDLE

URA_PCH CELL_PCH

CELL_DCH

n UE transceives uplink and downlink data

through dedicated channels (DPDCHs and

DPCCHs).

n During the time when there is no data

transmitted, CN may indicate UE’s

transiting to URA_PCH or CELL_PCH.

——Transit from CELL_DCH Mode

Sketch of RRC State Transition

RRC State Transition (III)

UE State transition

URA_PCH

CELL_DCH CELL_FACH

CELL_PCH

IDLE

DEAD

IDLE

DEAD

CELL_DCH

IDLE

CELL_DCH

URA_PCH CELL_PCH

CELL_FACH

——CELL_PCH and URA_PCH states

n UE has no activated uplink.

n Paging Information makes UE back toCELL_FACH or CELL_DCH mode.

n In CELL_PCH, UE should transit toCELL_FACH first to finish cell updating, andgo back if no service request.

n In URA_PCH, if URA changes, UE alsotransits to CELL_FACH to finish cell updatingfirst before it goes back to URA_PCH.

n System resource can be saved in these twomodes.

UE State transition

Sketch of RRC State Transition

RRC State Transition (IV)

Content

ATM Basics

Network Interfaces

UE State transition

Signaling flow

Basic Conception (1)

n RRC (Radio Resource Control)

� provides information transfer service to the NAS (Non Access

Stratum).

� responsible for controlling the configuration of UMTS radio

interface Layers 1 and 2.

n RRC Connection

� A point to point bidirectional connection between the RRC (Radio

Resource Control) entities on the UE (User Equipment) and

UTRAN (UMTS Terrestrial Radio Access Network).

� The UE requires an RRC connection to access the services of the

UMTS network.

Signaling flow

Basic Conception (2)

n RAB -Radio Access Bearer

� Identify the service the AS (Access Stratum) provides to the NAS

(Non Access Stratum) for transfer of user data between the UE

(User Equipment) and the CN (Core Network).

n RB -Radio Bearer

� The service provided by the Layer 2 for the transfer of user data

between UE (User Equipment) and UTRAN (UMTS Terrestrial

Radio Access Network).

Signaling flow

Basic Conception (3)

n RL (Radio Link)

� RL is a logical association between single UE (User Equipment)

and a single UTRAN (UMTS Terrestrial Radio Access Network)

access point.

� Its physical realization comprises one or more radio bearer

transmissions.

� It is possible for a UMTS mobile to have many radio links

established, when this occurs the mobile is said to be in a soft

handover.

Signaling flow

Sketch of the basic conceptions

Signaling flow

SRB0:CCCH(UL:RLC-TM, DL:RLC-UM) channel

SRB1:DCCH, RLC-UM mode transfer information

SRB2:DCCH, RLC-AM mode transfer，not includingRRC information used to bear NAS information.

SRB3,SRB4: optional configuration，DCCH, RLC-AM mode , including information used to bear NASinformation.

RB5-RB31 data RAB.

UE Call Procedure Overview

Signaling flow

StartupCell Searching

StartupCell Searching

LocationUpdate

LocationUpdate

StandbyStandby

RRCConnection Setup

RRCConnection Setup

NASConnection Setup

NASConnection Setup

HandoverHandoverCell/URAUpdate

Cell/URAUpdate

RLReconfiguration

RLReconfiguration

RB/RABReconfiguration

RB/RABReconfiguration

RABAssignment

RABAssignment

RRCConnection Release

RRCConnection Release

Call/Calledinitiate

Call/Calledinitiate

①

②

③

④ ⑤ ⑥

⑦

⑧

⑨

Trilogy of Call Setup

n RRC Connection Setup

� The signaling interacting in UTRAN is normal when receiving the

signaling ”RRC Connection Setup Complete”.

n NAS Connection Setup

� UE interacts with CN about the service request, authentication and

ciphering, etc. through the Non-Access Stratum (NAS) signaling,

n RAB Assignment

� CN allocates resource according to UE’s service requests.

Signaling flow

Call Setup Flow

� CN initiates a paging message to RNC.

� RNC judges the paging message from the CN and then sends a paging

message to the corresponding UE.

� If no RRC connection is available, UE will send a RRC connection setup

request message (RRC Connection Request) to RNC.

� RNC determines to set up a RRC connection according to the service

request and system resource occupation then sends a RRC connection

setup message (RRC Connection Setup) to UE.

� After signaling connection setup, the higher layer of UE (NAS) sends a

service request message to CN through a directly transfer message.

� CN sends a RAB assignment message (RAB Assignment Request) tothe RNC to allocate resource for UE’s request.

Signaling flow

UE Node B RNC

RRC RRC1.CCCH: RRC Connection Request

(UE identity, service type)Allocate RNTSelect L1

and L2 parameters

NBAP NBAP2.Radio Link Setup Request

Start RX

NBAP NBAP3.Radio Link Setup Response

ALCAP Iub Data Transport Bearer Setup

DCH-FP DCH-FP4.Downlink Synchronisation

DCH-FP DCH-FP5.Uplink Synchronisation

Start TX

RRC RRC6.CCCH: : RRC Connection Setup

RRC RRC7.DCCH: : RRC Connection Setup Complete

RRC setup

Signaling flow

RAB setup

UE SRNCNode B CNRAB ASSIGNMENT REQUEST

RL RECONFIG PRE (PSC, OVSF, POWER, phase etc,)

RL RECONFIG READY

RRC RB SETUP

RRC RB SETUP COMPLETERAB ASSIGNMENT RESPONSE

RL RECONFIG COMMIT

Signaling flow

Call Setup Flow

UE Node B RNC CN

RRC connection setup requestRRC connection setup

RAB assignment requestRL setup request

RL setup response

RB setup

RB setup completion

Paging (RANAP)Paging (RRC)

NAS message interaction (service request)

RAB assignment response

Signaling flow

Initial direct transfer & Initial UE message

Soft Handover Flow

UE NodeB（DRNS) DRNCNodeB

(SRNS)Measurement

report

RL creation requestRL setup request

Active set update command

SRNC

RL setup response RL setup response

Active set update completion

RL Deletion request

RL Deletion response

A

B

Signaling flow

Inter-frequency handover Flow

UE Target NodeB SRNCOriginal

NodeB

Measurement report

RL setup request

Reconfiguration command

RL setup response

Reconfiguration completion

RL deletion request

RL deletion response

Signaling flow

Call setup flow (1)

Signaling flow

Initial UE Identity, Establishment cause, Initial UE Capability

Cell id, Transport Format Set, Transport Format Combination Set,frequency, UL scrambling code, Power control information

Transport layer addressing information

ALCAP Protocol to establish User plane bearing

Iub interface data bearing synchronisation

Initial UE Identity, Transport Format Set, frequency,Transport Format Combination Set, Power control information。

Call setup flow (2)

Signaling flow

Service Request、Location Update Request

Call setup flow (3)

Signaling flow

Call Setup

Transport Format Set, Transport Format Combination Set,Power control information

Transport layer addressing information

Call setup flow (4)

Signaling flow

ALCAP bearing setup

Frame synchronization

Transport Format Set, Transport Format Combination Set

Call setup flow (5)

Signaling flow

Call setup flow (6)

Signaling flow

Exercise

n vertical:UTRAN interface universal model involve 4

planes,they are ( ) ( ) ( ) ( )

n horizontal :UTRAN interface universal model involve 2

layers, they are ( ) ( )

n pls write down IUCS\ IUPS \IUB interface control plane

application protocol and user plane protocol.

n Uu Interface is fall into ( )plane and ( ) plane.

n There are 3 layers in Uu Interface, they are ( ) ( ) ( ).

n pls describe the RRC setup procedure.