2-OWA000060 UMTS UTRAN Signaling Procedures

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Transcript of 2-OWA000060 UMTS UTRAN Signaling Procedures

  • Course ContentsChapter 1 UTRAN Network OverviewChapter 2 UTRAN Interface Chapter 3 Basic Signaling Process

  • UTRAN OverviewUE Working Mode and StateServing RNCDrift RNC and Control RNC Source RNC and Target RNC

    Lets discuss some basic notions.UE Working Mode and StateServing RNCDrift RNC and Control RNC Source RNC and Target RNCNotions about AREA

  • UE Working Modes and statesIdle ModeThe UE has no relation to UTRAN, only to CN. For data transfer, a signalling connection has to be established. UE camps on a cell

    It enables the UE to receive system information from the PLMN When registered and if the UE wishes to establish an RRC connection, it can do this by initially accessing the network on the control channel of the cell on which it is camped UE can receive "paging" message from control channels of the cell.It enables the UE to receive cell broadcast services. The idle mode tasks can be subdivided into three processes:

    PLMN selection and reselection;Cell selection and reselection;Location registration.

    When a UE is switched on, a public land mobile network (PLMN) is selected and the UE searches for a suitable cell of this PLMN to camp on. The NAS shall provide a list of equivalent PLMNs, if available, that the AS shall use for cell selection and cell reselection.The UE searches for a suitable cell of the chosen PLMN and chooses that cell to provide available services, and tunes to its control channel. This choosing is known as "camping on the cell". The UE will, if necessary, then register its presence, by means of a NAS registration procedure, in the registration area of the chosen cell.If the UE finds a more suitable cell, it reselects onto that cell and camps on it. If the new cell is in a different registration area, location registration is performed .

  • UE Working Modes and statesConnected Mode (Cell-DCH, Cell-FACH, Cell-PCH, URA-PCH)When at least one signalling connection exists, the UE is in connected mode and there is normally an RRC connection between UE and UTRAN. The UE position can be known on different levels:

    UTRAN Registration Area (URA) levelThe UE position is known on URA level. The URA is a set of cellsCell levelThe UE position is known on cell level. Different transport channel types can be used for data transfer:Common transport channels (RACH / FACH, DSCH, CPCH)Dedicated transport CHannels (DCH)

    The connected mode is entered when the RRC connection is established. The UE is assigned a Radio Network Temporary Identity (RNTI) to be used as UE identity on common transport channels. Two types of RNTI exist. The Serving RNC allocates an s-RNTI for all UEs having an RRC connection. The combination of s-RNTI and an RNC-ID is unique within a PLMN. c-RNTI is allocated by each Controlling RNC through which UE is able to communicate on DCCH. cRNTI is always allocated by UTRAN when a new UE context is created to an RNC, but the UE needs its c-RNTI only for communicating on common transport channels.The UE leaves the connected mode and returns to idle mode when the RRC connection is released or at RRC connection failure.Within connected mode the level of UE connection to UTRAN is determined by the quality of service requirements of the active radio bearers and the characteristics of the traffic on those bearers.The UE-UTRAN interface is designed to support a large number of UEs using packet data services by providing flexible means to utilize statistical multiplexing. Due to limitations, such as air interface capacity, UE power consumption and network h/w availability, the dedicated resources cannot be allocated to all of the packet service users at all times.Variable rate transmission provides the means that for services of variable rate the data rate is adapted according to the maximum allowable output power.The UE state in the connected mode defines the level of activity associated to the UE. The key parameters of each state are the required activity and resources within the state and the required signalling prior to the data transmission. The state of the UE shall at least be dependent on the application requirement and the period of inactivity.Common Packet Channel (CPCH) uplink resources are available to UEs with an access protocol similar to the RACH. The CPCH resources support uplink packet communication for numerous UEs with a set of shared, contention-based CPCH channels allocated to the cell.The different levels of UE connection to UTRAN are listed below:-No signalling connection existsThe UE is in idle mode and has no relation to UTRAN, only to CN. For data transfer, a signalling connection has to be established.-Signalling connection existsWhen at least one signalling connection exists, the UE is in connected mode and there is normally an RRC connection between UE and UTRAN. The UE position can be known on different levels:-UTRAN Registration Area (URA) levelThe UE position is known on URA level. The URA is a set of cells-Cell levelThe UE position is known on cell level. Different transport channel types can be used for data transfer:-Common transport channels (RACH / FACH, DSCH, CPCH)-Dedicated transport CHannels (DCH)Assuming that there exists an RRC connection, there are two basic families of RRC connection mobility procedures, URA updating and handover. Different families of RRC connection mobility procedures are used in different levels of UE connection (cell level and URA level):-URA updating is a family of procedures that updates the UTRAN registration area of a UE when an RRC connection exists and the position of the UE is known on URA level in the UTRAN;-handover is a family of procedures that adds or removes one or several radio links between one UE and UTRAN when an RRC connection exists and the position of the UE is known on cell level in the UTRAN.

  • UE Working Modes and states

    Cell-DCH

    In active stateCommunicating via its dedicated channels UTRAN knows which cell UE is in.

  • Cell-FACH and Cell-PCH StateCell-FACH

    In active stateFew data to be transmitted both in uplink and in downlink. There is no need to allocate dedicated channel for this UE. Downlink uses FACH and uplink uses RACH. UE need to monitor the FACH for its relative information. UTRAN knows which cell UE is in. Cell-PCH

    No data to be transmitted or received. Monitor PICH, to receive its paging. lower the power consumption of UE.UTRAN knows which cell UE is in.UTRAN have to update cell information of UE when UE roams to another cell

    If there is only few data to be transmitted,there is no need to allocate dedicated channel. Thus UE will be in Cell-FACH. UE in Cell-FACH state is communicating via FACH (downlink) and RACH (uplink) with UTRAN. UE need to monitor the FACH for its relative information because FACHs is shared for all users in the cell.If UE has no data to be transmitted or received, UE will be in Cell-PCH or URA-PCH. In these two states, UE needs to monitor PICH,to receive its paging. UTRAN knows which cell or URA UE is now in. The difference between Cell-PCH and URA-PCH is that UTRAN update UE information only after UE which is in URA-PCH state has roamed to other URA. UTRAN have to update cell information of UE when UE roams to another cell. UE migrates to cell-FACH state to complete the cell update. If there is also no data to be transmitted or received, UE is back to CELL-PCH state after cell update. If the cell update times in a fixed time reach a preset value, UTRAN will let UE migrate to URA-PCH. URA is an area of several cells.

  • URA-PCH StateURA-PCH

    No data to be transmitted or received. Monitor PICH. UTRAN only knows which URA (UTRAN Registration Area, which consists of multiple cells) that UE is in.UTRAN update UE information only after UE has roamed to other URA. A better way to lower the resource occupancy and signaling transmission

    It is the same as the CELL-PCH state. UE should migrate to CELL-FACH state to complete the URA update.

  • UE states

    - Scanning networks (PLMN)- Camp on cell- Monitor paging channel- cell re-selection- Dedicated Channel- Radio bearers Transmission Services- upper layer Signalingtrigger (CN)- Reduce actionDTXand save powerRRC connection

    This is the UE states figure. These states are significant only for UTRAN and UE. They are transparent to CN. Lets focus on the switch between the states.

  • SRNC/DRNC

    SRNC and DRNC are on a per connection basis between a UE and the UTRAN The SRNC handles the connection to one UE, and may borrow radio resources of a certain cell from the CRNC Drift RNSs support the Serving RNS by providing radio resourcesA UE in connection state has at least one and only one SRNC, but can has 0 or multiple DRNCs

    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 .For each connection between User Equipment and the UTRAN, One RNS is the Serving RNS. When required, Drift RNSs support the Serving RNS by providing radio resources. The role of an RNS (Serving or Drift) is on a per connection basis between a UE and the UTRAN.

  • CRNCThe CRNC owns the radio resources of a cell Dynamical control of power for dedicated channels, within limits admitted by CRNC, is done by the SRNC. Scheduling of data for dedicated channels is done by the SRNC, while for common channels it is done by the CRNC

    Then what is CRNC ? CRNC is related to a specific NodeB (or Cell)

  • Source RNC/Target RNCThe SRNS Relocation function coordinates the activities when the SRNS role is to be taken over by another RNS. Source RNC is the SRNC before SRNs Relocation and Target RNC is the SRNC after SRNs Relocation

    Now lets see the distinction of Source RNC and Target RNC. First lets understand a notion:SRNC relocation. Source RNC and Target RNC refer to different RNCs during a SRNC Relocation process. Source RNC is the SRNC before SRNC Relocation and Target RNC is the SRNC after SRNC Relocation .

  • Course ContentsChapter 1 UTRAN Network OverviewChapter 2 UTRAN InterfaceChapter 3 Basic Signaling Process

  • Chapter 2 UTRAN Interface

    Iu InterfaceUu InterfaceIub Interface

  • Iu Interface System Structure

  • Iu-CS Interface Protocol Stack Structure

    1,Physical Layer:The physical layer provides transport channels for ATM cells. It adds transport overheads to the ATM cells from the upper ATM layer to form consecutive bit stream. It also extracts the valid ATM cells from the consecutive bit stream received from the physical media and transports them to the ATM layer.The physical layer comprises two sublayers: Transmission Convergence (TC) sublayer and Physical Media (PM) sublayer.

    2,ATM Layer:Asynchronous Transfer Mode (ATM) layer is above the physical layer and communicates with its peer layer by utilizing services provided by the physical layer. The communication unit is cell. The ATM layer is independent of the type of the physical medium, the actual implementation of the physical layer and the type of the services transported. It only identifies and processes cell headers. That is to say, the ATM layer inserts a 5-byte header to the 48-byte cell payload transported from its upper layer, or removes the header from the cells transported from the physical layer and transports it to the upper layer.

    3,AAL2: AAL2 focuses on VBR (low rate) services with specific timing requirements, for example, compression voice service. In this kind of services, the data packets generated are too small to fill a cell, but to wait for enough data packets to fill the cell will surely lead to great delay. Therefore, AAL protocol multiplexes multiple users in one ATM channel, i.e., it fills a cell with the data packets from multiple users and adds a header to each packet to indicate which user it comes from.

    4,AAL5:AAL5 protocol is an AAL protocol especially made for Category-C connection oriented services for the purpose of efficiency improvement on the basis of AAl3/4. AAL5 protocol includes two sublayers: Segment And Reassemble (SAR) and Common part Convergence Sublayer (CPCS). The Segment And Reassemble (SAR) sublayer in the AAL5 segments the CPCS-PDU into 48-byte SAR-PDU without any overheads. Reassembly function is achieved during PDU receiving.

    5,SSCOP:SSCOP provides reliable transmission process for SSCOP applications (SSCF entities) that transmits messages with maximum 64k byte length.

    6,SSCF:The SSCF functions as the adaptation layer of the SSCOP and the upper layer applications. Upper layer applications refer to NBAP, MTP3-B and Signal Transporter (STC). The MTP3-B is used for NNI, which has higher link quality. SAAL is required to support link quality check and to help the MTP3-B with link switchover. But, NBAP is used for User Network Interface (UNI), which has poorer link quality and greater delay. Therefore, SSCF is divided into SSCF-NNI and SSCF-UNI to cater to different upper layer applications.

    7,MTP3-B:Based on Message Transfer Part Layer 3 (MTP3), MTP3-B is the protocol specification aiming at ATM features. As the signaling transport layer, MTP3-B is responsible for transferring signaling messages, managing signaling networks and signaling links. It performs message exchange via the services provided by SAAL.

    8,ALCAP:Access Link Control Application Part (ALCAP), also called Q.AAL2 protocol, complies with ITU-T Q.2630.1 and resides in the user plane of the Iub/Iur/Iu-CS transport network layer with the signaling bearers of SAAL UNI type and MTP3-B type. ALCAP consists of a Q.AAL2 protocol processing layer (one plane) and two STC adaptation layers (the other plane) in which the former plane performs all protocol functions while the latter one adapts primitives and shield bottom-layer differences (SAAL, MTP3-B). The basic function of ALCAP is establishing and releasing AAL2 connection between two SPs. Besides, it also maintains and manages such resources as path, tunnel in the micro cell of the signaling system. The AAL2 connections controlled by ALCAP shall be regarded as the transmission bearer for the control plane and user plane of the radio network layer.

    9,SCCP:Signaling Connection Control Part (SCCP) is used to enhance the functions of Message Transfer Part (MTP). Equivalent to the layer 3 of Open Systems Interconnection (OSI), it implements the packet switching function of virtual circuit and datagram. As the addressing function of MTP only can be used to transmit messages to nodes, only the connectionless message transfer function is provided. While SCCP is able to provide a type of addressing function to identify each SCCP user in a node using DPC and subsystem number (SSN). The SCCP performs network service, routing and management functions.

  • Iu-PS Interface Protocol Stack Structure

    1,Iu-PS Data Bearer:The structure of Iu-PS user-plane data bearer is shown in slide. Working in IP over ATM (IPoA) bearing mode, the AAL layer takes AAL5 as the ATM adaptation type.

    2,IP:Internet Protocol (IP) provides a globally unified addressing mode to shield the differences between physically network addresses, thus enabling route search. Besides, it also provides a globally unified packet format to shield the differences between network link layers, thus enabling network interconnection.

    3,UDP:Providing connectionless service, User Datagram Protocol (UDP) increases port addresses based on IP to distinguish different applications on a host. For example, the destination port number used by GTP-U is 2152 and the source port number is an arbitrary value distributed by the transmitting end.

    4,GTP-UGPRS Tunnel Protocol User Plane (GTP-U) transmits Iu-PS user-plane data and manages Iu-PS user-plane paths. As 3G supports the transmissions of multiple types of packet data and will further support more types of such data due to the function enhancement in the future, GTP-U adopts a versatile tunnel encapsulation method based on GTP to encapsulate various packet data for transparent transmissions, facilitating the supporting for these data.

  • Iu Interface Protocol Stack Structure

    Physical (Full Rate E1 or STM1 Optical)ATM Lower LayersAAL2AAL5 - SAAL NNIMTP3-B

    IPQ.2150Q.2630Q.AAL2Frame ProtocolUnrestricted DigitalVoice DataSCCPRANAPUDPGTP-UPacketBearerCSBearerPSBearerControlSignalingRANAP: Radio Access Network Application Part

  • Iu Interface Functions(1)Mobility ManagementLocation Area ReportSRNS RelocationHard handover between RNCs and inter-system handoverRadio Access BearerRABManagementEstablishment, Modification and Release of RABIu data transmissionnormal data transmissionabnormal data transmissionTransparent transmission of UE-CN connection information

  • Iu Interface Functions2PagingIu ReleaseSecurity Mode ControlOverload ControlCommon UE IDIMSIManagementIu Signaling Trace ManagementIu Interface Abnormality ManagementCBS(Cell Broadcast Service) Control

  • Chapter 2 UTRAN Interface

    Iu InterfaceUu InterfaceIub Interface

  • Uu Interface Protocol Stack Structure

    Uu interface is the interface between User Equipment (UE) and UMTS Terrestrial Radio Access Network (UTRAN) and it is the most important interface in the WCDMA system.The radio interface is layered into three protocol layers:-the physical layer (L1);-the data link layer (L2);-network layer (L3).Layer 2 is split into following sublayers: Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP) and Broadcast/Multicast Control (BMC).Layer 3 and RLC are divided into Control (C-) and User (U-) planes. PDCP and BMC exist in the U-plane only.

  • Uu Interface L1 Functions1Multiplexing of transport channels and de-multiplexing of encoded composite channelsMapping of encoded composite transport channels on physical channelsMacro-diversity distribution/combining and soft handover executionError detection on transport channels and indication to higher layersFEC encoding/decoding and interleaving/de-interleaving of transport channelsRate matching of coded transport channels to physical channelsPower weighting and combining of physical channelsclosed-loop power controlopen-loop power control

    The physical layer offers information transfer services to MAC and higher layers. The physical layer transport services are described by how and with what characteristics data are transferred over the radio interface. An adequate term for this is 'Transport Channel'.

  • Uu Interface L1 Functions2Modulation and spreading/demodulation and de-spreading of physical channelsSynchronization between frequency and time (chip, bit, slot, frame)Radio characters measurements (FER, SIR, Interference power) and indication to higher layersCompressed mode supportDiversity of Transmission/ReceivingOther base band processing functions

  • RLC FunctionsSegmentation, re-assembly and Padding Transmission of user data Error correction using different transport Format In-sequence delivery of higher layer PDUs, duplicate detection Flow control Sequence number check in Unacknowledged ModeUM Protocol error detection and recovery Ciphering Suspend/resume function

    RLC Functions:-Segmentation and reassembly. This function performs segmentation/reassembly of variable-length upper layer PDUs into/from smaller RLC PDUs. The RLC PDU size is adjustable to the actual set of transport formats.-Transfer of user data. This function is used for conveyance of data between users of RLC services. RLC supports acknowledged, unacknowledged and transparent data transfer. QoS setting controls transfer of user data.-Error correction. This function provides error correction by retransmission (e.g. Selective Repeat, Go Back N, or a Stop-and-Wait ARQ) in acknowledged data transfer mode.-In-sequence delivery of upper layer PDUs. This function preserves the order of upper layer PDUs that were submitted for transfer by RLC using the acknowledged data transfer service. If this function is not used, out-of-sequence delivery is provided.-Duplicate Detection. This function detects duplicated received RLC PDUs and ensures that the resultant upper layer PDU is delivered only once to the upper layer.-Flow control. This function allows an RLC receiver to control the rate at which the peer RLC transmitting entity may send information.-Sequence number check. This function is used in unacknowledged mode and guarantees the integrity of reassembled PDUs and provides a mechanism for the detection of corrupted RLC SDUs through checking sequence number in RLC PDUs when they are reassembled into a RLC SDU. A corrupted RLC SDU will be discarded.-Protocol error detection and recovery. This function detects and recovers from errors in the operation of the RLC protocol.-Ciphering. This function prevents unauthorised acquisition of data. Ciphering is performed in RLC layer for non-transparent RLC mode. -Suspend/resume function. Suspension and resumption of data transfer.

  • RRC Functions1Management of system information broadcastPaging/NotificationRRC connection management establishreconfig, maintain and releaseRadio Bearer (RB) Managementestablish, reconfig and release, support NAS servicesRRC connection mobility management initial cell selectionRouting of higher layer PDUsControl of requested QoS and map into different resources of Access StratumManagement and control of radio resources

    The Radio Resource Control (RRC) layer handles the control plane signalling of Layer 3 between the UEs and UTRAN. The RRC performs the following functions:-Broadcast of information provided by the non-access stratum (Core Network). The RRC layer performs system information broadcasting from the network to all UEs. The system information is normally repeated on a regular basis. The RRC layer performs the scheduling, segmentation and repetition. This function supports broadcast of higher layer (above RRC) information. This information may be cell specific or not. As an example RRC may broadcast Core Network location service area information related to some specific cells.- Broadcast of information related to the access stratum. The RRC layer performs system information broadcasting from the network to all UEs. The system information is normally repeated on a regular basis. The RRC layer performs the scheduling, segmentation and repetition. This function supports broadcast of typically cell-specific information.- Paging/notification. The RRC layer can broadcast paging information from the network to selected UEs. Higher layers on the network side can request paging and notification. The RRC layer can also initiate paging during an established RRC connection.-Establishment, re-establishment, maintenance and release of an RRC connection between the UE and UTRAN. The establishment of an RRC connection is initiated by a request from higher layers at the UE side to establish the first Signalling Connection for the UE. The establishment of an RRC connection includes an optional cell re-selection, an admission control, and a layer 2 signalling link establishment. The release of an RRC connection can be initiated by a request from higher layers to release the last Signalling Connection for the UE or by the RRC layer itself in case of RRC connection failure. In case of connection loss, the UE requests re-establishment of the RRC connection. In case of RRC connection failure, RRC releases resources associated with the RRC connection.-Establishment, reconfiguration and release of Radio Bearers. The RRC layer can, on request from higher layers, perform the establishment, reconfiguration and release of Radio Bearers in the user plane. A number of Radio Bearers can be established to an UE at the same time. At establishment and reconfiguration, the RRC layer performs admission control and selects parameters describing the Radio Bearer processing in layer 2 and layer 1, based on information from higher layers.-Assignment, reconfiguration and release of radio resources for the RRC connection. The RRC layer handles the assignment of radio resources (e.g. codes, CPCH channels) needed for the RRC connection including needs from both the control and user plane. The RRC layer may reconfigure radio resources during an established RRC connection. This function includes coordination of the radio resource allocation between multiple radio bearers related to the same RRC connection. RRC controls the radio resources in the uplink and downlink such that UE and UTRAN can communicate using unbalanced radio resources (asymmetric uplink and downlink). RRC signals to the UE to indicate resource allocations for purposes of handover to GSM or other radio systems.- RRC connection mobility functions. The RRC layer performs evaluation, decision and execution related to RRC connection mobility during an established RRC connection, such as handover, preparation of handover to GSM or other systems, cell re-selection and cell/paging area update procedures, based on e.g. measurements done by the UE.-Initial cell selection and re-selection in idle mode. Selection of the most suitable cell based on idle mode measurements and cell selection criteria.-Routing of higher layer PDUs. This function performs at the UE side routing of higher layer PDUs to the correct higher layer entity, at the UTRAN side to the correct RANAP entity.

  • RRC Functions2Management and control of RB, transport channel and physical channelopen loop power controlSupport of SRNS relocationControl of UE measurement and measurement reportCiphering control, protection of integrity CBS related functionsBMC configurationCBS radio resource distribute request, support of CBS non-continuous receiving

    RRC Functions (Continue)- Outer loop power control. The RRC layer controls setting of the target of the closed loop power control.- Control of requested QoS. This function shall ensure that the QoS requested for the Radio Bearers can be met. This includes the allocation of a sufficient number of radio resources.- UE measurement reporting and control of the reporting. The measurements performed by the UE are controlled by the RRC layer, in terms of what to measure, when to measure and how to report, including both UMTS air interface and other systems. The RRC layer also performs the reporting of the measurements from the UE to the network.-Control of ciphering. The RRC layer provides procedures for setting of ciphering (on/off) between the UE and UTRAN. -Integrity protection. This function adds a Message Authentication Code (MAC-I) to those RRC messages that are considered sensitive and/or contain sensitive information. -Initial Configuration for CBSThis function performs the initial configuration of the BMC sublayer.-Allocation of radio resources for CBSThis function allocates radio resources for CBS based on traffic volume requirements indicated by BMC. The radio resource allocation set by RRC (i.e. the schedule for mapping of CTCH onto FACH/S-CCPCH) is indicated to BMC to enable generation of schedule messages. The resource allocation for CBS shall be broadcast as system information.-Configuration for CBS discontinuous receptionThis function configures the lower layers (L1, L2) of the UE when it shall listen to the resources allocated for CBS based on scheduling information received from BMC.

  • Chapter 2 UTRAN Interface

    Iu InterfaceUu InterfaceIub Interface

  • Iub Interface Protocol Stack

    Physical (Full Rate E1 or STM1 Optical)ATM Lower LayersAAL2AAL5 - SAAL UNINBAP

    Q.2150Q.2630Q.AAL2Frame ProtocolRLC / MACRRCMSSignalingCC/MM/RR

    UnrestrictedDigital/VoicePacketCSBearerPSBearerControlSignalingNBAP: Node B Application PartRRC: Radio Resource ControlRLC: Radio Link ControlMAC: Medium Access Control

  • Iub Interface Functions(1)Common FunctionsCommon Transport Channel ManagementIub Common Channel Data TransmissionLogical O&M of Node Bmaintenance functions such as cell configuration ManagementFault ManagementBlock Management, etc.System Information ManagementCommon MeasurementResource VerificationAbnormality ManagementTiming and Synchronization Management

  • Iub Interface Functions(2)Dedicated FunctionsDedicated Transport Channel Management Radio Link(RL) Monitoring Dedicated Measurement ManagementTiming and Synchronization ManagementUp-link outer loop Power ControlIub Dedicated Data transmissionBalance on down-link power driftingCompressed Mode Control

  • Course ContentsChapter 1 UTRAN Network OverviewChapter 2 UTRAN InterfaceChapter 3 Basic Signaling procedures

  • Basic Signaling Procedures

    3.1 Call overall procedures3.2 Network start procedures3.3 UE registration procedures3.4 Calling procedures3.5 Connection mobility management procedures

    Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.

  • Call overall Procedures

    Step 8Waiting for call again1cell selection2wait for call

    First of all, the network should be started. Then UE power on. After cell reselection and location registration UE enters idle mode and can call or waits for call. Now if UE receives a paging information, the UE will begin RRC connection establish and enter connected mode. RRC connection establish only setup the connection between UE and UTRAN. The next step of NAS signaling connection establish setup the connection between UTRAN and CN. Then CN processes RAB set up. RAB set up includes synchronous set up and asynchronous set up. The difference will introduce in the back slide. Now UE can begin call. During the call, if UE moves from one cell to another, handover will happen; if the service source rate changes, RAB/RB modification,physical channel reconfiguration and transport channel reconfiguration will happen. After the call, RRC connection release and UE enter idle mode again.

  • Basic Signaling Procedures

    3.1 Call overall procedures3.2 Network start procedures3.3 UE registration procedures3.4 Calling procedures3.5 Connection mobility management procedures

    Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.

  • System Information Broadcast Flow

    . 3.BCCH:System Information1.System Information Update RequestUENode BRNCCNNBAPNBAPRRCRRC. 4.BCCH:System InformationRRCRRC 5.BCCH:System InformationRRCRRC. 2.System Information Update ResponseNBAPNBAP

    Network start process is the System Information Broadcast Flow. First RNC sendsthen NodeB responseNodeB sends system information to UE through BCCH. We can see that nodeb sends system information three times thus to increasing UEs receiving ratio.

  • Basic Signaling Procedures

    3.1 Call overall procedures3.2 Network start procedures3.3 UE registration procedures3.4 Calling procedures3.5 Connection mobility management procedures

    Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.

  • RRC Connection Establishment Flow(CCH)

    UE originate RRC connection setup for registration.SRNC decides to establish RRC connection on common channel,and uses pre-configured common channel resources.

    This is RRC Connection Establishment flow. First UE originate RRC connection setup for registration. SRNC decides to establish RRC connection on common channel, and uses pre-configured common channel resources. Then SRNC sends message of RRCconnection setup to UE. UE response message of RRCconnection setup complete. Thus the flow finishes.

  • NAS Signaling Establishment Flow

    UE changes DT messages with CN, such as Authentication, connection establishment, location registration, etc.

    This is the NAS Signaling Establishment Flow .The main function of NAS Signaling Establishment Flow is UE changes DT messages with CN, such as Authentication, connection establishment, location registration, etc.

  • RRC Connection Release Flow(CCH)

    In registration process, UE does not use dedicated user plane resources. Instead, it release signaling link directly. Thus registration procedure ends.

    In registration process, UE does not use dedicated user plane resources. Instead, it release signaling link directly. First is IU release and then is RRC connection release. Thus registration procedure ends.

  • Basic Signaling Procedures

    3.1 Call overall procedures3.2 Network start procedures3.3 UE registration procedures3.4 Calling procedures3.5 Connection mobility management procedures

    Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.

  • Paging Flow (UE in Idle State or PCH State)

    CN sends paging message and specifies UE and paging area. CN is responsible for paging message re-send. SRNC sends relevant paging message according to UE state.

    This example shows how paging is performed for a UE in RRC Idle Mode. The UE may be paged for a CS or PS service. Since the UE is in RRC Idle Mode, the location is only known at CN level and therefore paging is distributed over a defined geographical area

  • Paging Flow (connection mode)

    CN sends paging message and specifies UE and paging area. CN is responsible for paging message re-send. SRNC sends relevant paging message according to UE state.

    This can occur in case of two core network domains, with the mobility management independent of each other. Two possible solutions exists:The UTRAN coordinates the paging request with the existing RRC connection.The UE coordinates the paging request with the existing RRC connection.

  • RRC Connection Establishment Flow(DCH)

    1.The UE initiates set-up of an RRC connection by sending RRC Connection Request message on CCCH.Parameters: Initial UE Identity, Establishment cause.2.The SRNC decides to use a DCH for this RRC connection, allocates U-RNTI and radio resources for the RRC connection. When a DCH is to be set-up, NBAP message Radio Link Setup Request is sent to Node B.Parameters: Cell id, Transport Format Set, Transport Format Combination Set, frequency, UL scrambling code (FDD only), Time Slots (TDD only), User Codes (TDD only), Power control information.3.Node B allocates resources, starts PHY reception, and responds with NBAP message Radio Link Setup Response.Parameters: Signalling link termination, Transport layer addressing information (AAL2 address, AAL2 Binding Identity) for the Iub Data Transport Bearer.4.SRNC initiates set-up of Iub Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to the DCH. The request for set-up of Iub Data Transport bearer is acknowledged by Node B.5./6.The Node B and SRNC establish synchronism for the Iub and Iur Data Transport Bearer by means of exchange of the appropriate DCH Frame Protocol frames Downlink Synchronisation and Uplink Synchronisation. Then Node B starts DL transmission.7.Message RRC Connection Setup is sent on CCCH from SRNC to UE.Parameters: Initial UE Identity, U-RNTI, Capability update Requirement, Transport Format Set, Transport Format Combination Set, frequency, DL scrambling code (FDD only), Time Slots (TDD only), User Codes (TDD only), Power control information.8.Node B achieves uplink sync and notifies SRNC with NBAP message Radio Link Restore Indication.9.Message RRC Connection Setup Complete is sent on DCCH from UE to SRNC.Parameters: Integrity information, ciphering information, UE radio access capability.

  • NAS Signalling Connection Establishment

    The NAS signalling connection between UE and CN can now be used for NAS message transfer

    1.RRC Connection is established (see 7.3.1 or 7.3.2).2.UE sends RRC Initial Direct Transfer to SRNC.Parameters: Initial NAS Message (could for a GSM based CN be e.g. CM Service Request, Location Update Request etc.) CN node indicator (it indicates the correct CN node into which the NAS message shall be forwarded).3.SRNC initiates signalling connection to CN, and sends the RANAP message Initial UE Message.Parameters: NAS PDU (could for a GSM based CN be e.g. CM Service Request, Location Update Request etc.), CN domain indicator (indicating the CN domain towards which this message is sent).

  • RAB Establish Flow(DCH-DCH, synchronous)

    UESRNCNodeBCN RAB ASSIGNMENT REQUESTALCAP EstablishRL RECONFIG PRERL RECONFIG READYALCAP Establish, synchronizationRRCRB SETUPRRCRB SETUP COMPLETERAB ASSIGNMENT RESPONSERL RECONFIG COMMITThere are more than one ALCAP establish procedures on Iu Interface, more than one user plane RABs can be established simultaneously. After user plane establish, UE enters call connection.

    1. CN initiates establishment of the radio access bearer with RANAP message Radio Access Bearer Assignment Request.Parameters: Radio Access Bearer parameters, User Plane Mode, Transport Address, Iu Transport Association.SRNC initiates set-up of Iu Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iu Data Transport Bearer to the Radio Access Bearer (this step is not required towards PS domain). SRNC requests its Node B to prepare establishment of DCH to carry the radio access bearer (Radio Link Reconfiguration Prepare).Parameters: Transport Format Set, Transport Format Combination Set, Power control information, Time Slots (TDD only), User Codes (TDD only). Node B allocates resources and notifies SRNC that the preparation is ready (Radio Link Reconfiguration Ready).Parameters: Transport layer addressing information (AAL2 address, AAL2 Binding Id) for Iub Data Transport Bearer. SRNC initiates setup of Iub Data Transport Bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to DCH. NBAP message Radio Link Reconfiguration Commit is sent from SRNC to Node B. RRC message Radio Access Bearer Setup is sent by SRNC to UE.Parameters: Transport Format Set, Transport Format Combination Set, UE sends RRC message Radio Access Bearer Setup Complete to SRNC.9.SRNC sends RANAP message Radio Access Bearer Assignment Response to CN.

  • RAB Establish Flow(DCH-DCH, asynchronous)

    UESRNCNodeBCNRAB ASSIGNMENT REQUESTALCAP EstablishRL RECONFIG REQRL RECONFIG RESPALCAP Establish, synchronizationRRCRB SETUPRRCRB SETUP COMPLETERAB ASSIGNMENT RESPONSE

    1. CN initiates establishment of the radio access bearer with RANAP message Radio Access Bearer Assignment Request.Parameters: Radio Access Bearer parameters, User Plane Mode, Transport Address, Iu Transport Association.SRNC initiates set-up of Iu Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iu Data Transport Bearer to the Radio Access Bearer (this step is not required towards PS domain). SRNC requests its Node B setup a new DCH in the existing Radio Link sending the RL Reconfiguration Request message.Parameters: Bearer ID, Transport Format Set, Transport Format Combination Set, Power control information. Node B allocates resources and notifies SRNC that the setup is sending the RL Reconfiguration Response.Parameters: Transport layer addressing information (AAL2 address, AAL2 Binding Id) for Iub Data Transport Bearer. SRNC initiates setup of Iub Data Transport Bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to DCH. RRC message Radio Access Bearer Setup is sent by SRNC to UE.Parameters: Transport Format Set, Transport Format Combination Set, UE sends RRC message Radio Access Bearer Setup Complete to SRNC.8.SRNC sends RANAP message Radio Access Bearer Assignment Response to CN.

  • Transport Channel Reconfig Flow(Synchronised )

    UENodeBSRNCRL RECONFIG PREPARERL RECONFIG READYRL RECONFIG COMMITTRANSPORT CHANNEL RECONFIGTRANSPORT CHANNEL RECONFIG COMPLETEALCAP Establish, synchronizationALCAP Release

    RNC requests its Node B to prepare reconfiguration of DCH (Radio Link Reconfiguration Prepare).Parameters: Transport Format Set, Transport Format Combination Set, Power control information Node B allocates resources and notifies SRNC that the reconfiguration is ready (Radio Link Reconfiguration Ready).Parameters: Transport layer addressing information (AAL2 address, AAL2 Binding Id) for Iub Data Transport Bearer. SRNC initiates (if needed) establishment of new Iub Data Transport Bearers using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to DCH.

    NBAP message Radio Link Reconfiguration Commit is sent from SRNC to Node B.Parameters: CFN.4. RRC message Transport Channel Reconfiguration is sent by SRNC to UE.UE sends RRC message Transport Channel Reconfiguration Complete to SRNC. Not used resources in SRNC and Node B (Serving RNS) are released. SRNC initiates release of Iub (Serving RNS) Data Transport bearer using ALCAP protocol.

  • Physical Channel Reconfig Flow

    1.SRNC requests its Node B to prepare reconfiguration of physical channel (Radio Link Reconfiguration Prepare).Parameters: Power control information . 2. Node B allocates resources and notifies SRNC that the reconfiguration is ready (Radio Link Reconfiguration Ready).Parameters: Transport layer addressing information (AAL2 address, AAL2 Binding Id) for Iub Data Transport Bearer. 3. NBAP message Radio Link Reconfiguration Commit is sent from SRNC to Node B.Parameters: CFN. 4. RRC message Physical Channel Reconfiguration is sent by SRNC to UE.Parameters: UL scrambling code (FDD only), Time Slots (TDD only), User Codes (TDD only), CFN. 5. Both UE and Nodes B actualise modification of the physical channel.6. UE sends RRC message Physical Channel Reconfiguration Complete to SRNC.

  • RRC Release FlowDCH

    UENodeBSRNCCNIU RELEASE COMMANDIU RELEASE COMPLETEALCAP ReleaseRRCRRC CONNECTION RELEASERRCRRC CONNECTION RELEASE COMPLETERL DELETIONRL DELETION RESPONSEALCAP Release

    Release procedure is usually originated by CN. But if UE is faulty, SRNC can also request release.

    1.The CN initiates the release of a dedicated Channel by sending the message Iu Release Command to the SRNC.Parameters: Cause.2.The SRNC confirms the release by sending a Iu Release Complete message to the CN. Parameters: Data volume Report (if data volume reporting to PS is required).The SRNC initiates release of Iu Data Transport bearer using ALCAP protocol. 4.Message RRC Connection Release from SRNC to UE to initiate the RRC connection release.Parameters: Cause.Message RRC Connection Release Complete from UE to SRNC to confirm the RRC connection release. The SRNC initiates the release of the link by sending the Radio Link Deletion to the Node B (SRNC). The Node B (SRNC) confirms the release of the link by sending the Radio Link Deletion Response to the SRNC. The Node B (SRNC) initiates release of Iub Data Transport bearer using ALCAP protocol.

  • Overall Called Signaling Flow

  • Overall Called Signaling Flow

  • Overall Called Signaling Flow

  • Overall Called Signaling Flow

  • Overall Called Signaling Flow

  • Overall Called Signaling Flow

  • Basic Signaling Procedures

    3.1 Call overall procedures3.2 Network start procedures3.3 UE registration procedures3.4 Calling procedures3.5 Connection mobility management procedures

    Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.

  • Soft Handover

    Macro diversity is a operation state in which a User Equipment simultaneously has radio links with two or more UTRAN access points. The aim is to improve quality of the radio connection or provide seamless connection.Active Set is a set of radio links simultaneously involved in a specific communication service between an UE and a UTRAN access point.

    The following cases are considered:Radio Link Addition (Branch Addition);Radio link Deletion (Branch Deletion);Radio link Addition & Deletion (Branch Addition & Deletion - simultaneously).

  • Soft Handover Illustration (Intra RNC)

    Before Soft HandoverAfter Soft HandoverDuring Soft Handover

  • Soft Handover Illustration (Inter-RNC)

    Before Soft HandoverAfter Soft HandoverRadio Link(RL) is added and deleted simultaneously

    Soft handover inter-RNC is more complex than intra-RNC. It will refer to DRNC.

  • Soft Handover - Radio Link Addition

    1.SRNC decides to setup a radio link via a new cell controlled by another RNC. SRNC requests DRNC for radio resources by sending RNSAP message Radio Link Setup Request. If this is the first radio link via the DRNC for this UE, a new Iur signalling connection is established. This Iur signalling connection will be used for all RNSAP signalling related to this UE.Parameters: Cell id, Transport Format Set per DCH, Transport Format Combination Set, frequency, UL scrambling code.2.If requested resources are available, DRNC sends NBAP message Radio Link Setup Request to Node B.Parameters: Cell id, Transport Format Set per DCH, Transport Format Combination Set, frequency, UL scrambling code.Then Node B starts the UL reception.3.Node B allocates requested resources. Successful outcome is reported in NBAP message Radio Link Setup Response.Parameters: Signalling link termination, Transport layer addressing information (AAL2 address, AAL2 Binding Identitie(s)) for Data Transport Bearer(s).4.DRNC sends RNSAP message Radio Link Setup Response to SRNC. Parameters: Transport layer addressing information (AAL2 address, AAL2 Binding Identity) for Data Transport Bearer(s), Neighbouring cell information.5.SRNC initiates setup of Iur/Iub Data Transport Bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to DCH.This may be repeated for each Iur/Iub Data Transport Bearer to be setup.6./7.Node B achieves uplink sync on the Uu and notifies DRNC with NBAP message Radio Link Restore Indication. In its turn DRNC notifies SRNC with RNSAP message Radio Link Restore Indication.8./9.Node B and SRNC establish synchronism for the Data Transport Bearer(s) by means of exchange of the appropriate DCH Frame Protocol frames Downlink Synchronisation and Uplink Synchronisation, relative already existing radio link(s). Then Node B starts DL transmission.10.SRNC sends RRC message Active Set Update (Radio Link Addition) to UE on DCCH.Parameters: Update type, Cell id, DL scrambling code, Power control information, Ncell information.11.UE acknowledges with RRC message Active Set Update Complete.

  • Soft Handover - Radio Link Deletion

    1.SRNC decides to remove a radio link via an old cell controlled by another RNC. SRNC sends RRC message Active Set Update (Radio Link Deletion) to UE on DCCH.Parameters: Update type, Cell id.2.UE deactivates DL reception via old branch, and acknowledges with RRC message Active Set Update Complete.3.SRNC requests DRNC to deallocate radio resources by sending RNSAP message Radio Link Deletion Request.Parameters: Cell id, Transport layer addressing information.4.DRNC sends NBAP message Radio Link Deletion Request to Node B.Parameters: Cell id, Transport layer addressing information.5.Node B deallocates radio resources. Successful outcome is reported in NBAP message Radio Link Deletion Response.6.DRNC sends RNSAP message Radio Link Deletion Response to SRNC.7.SRNC initiates release of Iur/Iub Data Transport Bearer using ALCAP protocol.

  • Hard Handover Illustration (Intra-RNC)

    Before Har Handover 7 After Hard HandoverRadio Link(RL)cannot exist simultaneously

  • Hard Handover Illustration (Inter-RNC)

    Before Hard HandoverAfter Hard HandoverRadio Link(RL)cant exist simultaneously

    Usually, the Iur interface must exist at inter-RNC hard handover. Otherwise the UE involved relocation is need.

  • Hard Handover via Iur (DCH on Iur)

    1.SRNC sends Radio Link Setup Request message to the target RNC.Parameters: target RNC identifier, s-RNTI, Cell id, Transport Format Set, Transport Format Combination Set, [DSCH information]. (Note 1).2.The target RNC allocates RNTI and radio resources for the RRC connection and the Radio Link(s) (if possible), and sends the NBAP message Radio Link Setup Request to the target Node-B. Parameters: Cell id, Transport Format Set, Transport Format Combination Set, frequency, UL scrambling code (FDD only), Time Slots (TDD only), User Codes (TDD only), Power control information, [PDSCH code mapping (FDD only); TFCI2 bearer specific information (FDD only); TFCI signalling mode set to Hard Split (FDD only); DSCH information (TDD only)] etc.3.Node B allocates resources, starts PHY reception, and responds with NBAP message Radio Link Setup Response. Parameters: Signalling link termination, Transport layer addressing information for the Iub Data Transport Bearer, [DSCH information response, TFCI2 bearer information response (FDD only).].4.Target RNC initiates set-up of Iub Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to the DCH. The request for set-up of Iub Data Transport bearer is acknowledged by Node B [A separate transport bearer is established for the DSCH. Another transport bearer is established for the TFCI2 signalling information (FDD only).]5.When the Target RNC has completed preparation phase, Radio Link Setup Response is sent to the SRNC (see note1). [The message includes the DSCH information parameter.]6.SRNC initiates set-up of Iur Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iur Data Transport Bearer to the DCH. The request for set-up of Iur Data Transport bearer is acknowledged by Target RNC (see note 1). [A separate transport bearer is established for the DSCH.]7.SRNC sends a RRC message Physical Channel Reconfiguration to the UE.8.When the UE switches from the old RL to the new RL, the source Node B detects a failure on its RL and sends a NBAP message Radio Link Failure Indication to the source RNC.9.The source RNC sends a RNSAP message Radio Link Failure Indication to the SRNC (see note 2).10.When the RRC connection is established with the target RNC and necessary radio resources have been allocated, the UE sends RRC message Physical Channel Reconfiguration Complete to the SRNC.11.The SRNC sends a RNSAP message Radio Link Deletion Request to the source RNC (see note 2).12.The source RNC sends NBAP message Radio Link Deletion Request to the source Node B.Parameters: Cell id, Transport layer addressing information.13.The source Node B de-allocates radio resources. Successful outcome is reported in NBAP message Radio Link Deletion Response.14.The source RNC initiates release of Iub Data Transport bearer using ALCAP protocol. [The DSCH transport bearer and the TFCI2 bearer (FDD only) are released as well.]15.When the source RNC has completed the release the RNSAP message Radio Link Deletion Response is sent to the SRNC (see note 2).16.SRNC initiates release of Iur Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iur Data Transport Bearer to the DCH. The request for release of Iur Data Transport bearer is acknowledged by the Source RNC (see note 2). [The DSCH transport bearer is also released.]NOTE 1:This message is not necessary when the target RNC is the SRNC.NOTE 2:This message is not necessary when the source RNC is the SRNC.NOTE 3:The messages used are only one example of the various messages which can be used to trigger a handover, to confirm it or to indicate the handover failure.

  • Hard Handover FlowUMTS->GSM

    MAP/EMAP/E2. PrepareHandoverBSSMAPBSSMAP4. Handover Request AckRANAPRANAP13. Iu ReleaseCompleteBSSMAPBSSMAP3. Handover RequestMAP/EMAP/E5. Prepare Handover ResponseRANAPRANAP6. Relocation CommandBSSMAPBSSMAP8. Handover DetectBSSMAPBSSMAP10. Handover CompleteMAP/EMAP/E11. Send End Signal RequestMAP/E MAP/E14. Send End Signal ResponseRANAPRANAP1. Relocation RequiredUENode BRNCServingCNMSCBSCBTSRRC7. DCCH : Inter-System Handover CommandRRCRR9. Handover CompleteRRRANAPRANAP12. Iu Release Command

    1.Upon detection of a trigger SRNC sends RANAP message Relocation Required to the CN.2.The UMTS CN will forward this request to the GSM MSC (indicated in the received message) over the MAP/E interface (MAP message Prepare Handover).Steps 3 & 4 follow the normal GSM procedures and are shown only for clarity.5.Once initial procedures are complete in GSM MSC/BSS the MSC returns MAP/E message Prepare Handover Response.6.CN responds to the initial request from SRNC by sending RANAP message Relocation Command to the SRNC.7.Via existing RRC connection, SRNC sends RRC message Handover from UTRAN command to the UE. One or several message from the other system can be included in this message.

    Procedures related to synchronisation etc. to GSM BSS are not shown. Steps 8 & 10 follow normal GSM procedures and are shown only for clarity.11.Detection of the UE within the GSM coverage results in the MSC sending MAP/E message Send End Signal Request to the CN.12.CN initiates release of resources allocated by the former SRNC (Iu Release Command).13.Previously allocated bearer resources are released within UMTS (e.g. using RANAP and ALCAP protocols [ALCAP not shown]) (Iu Release Complete).14.Procedure is concluded from UMTS point of view by CN sending MAP/E message Send End Signal Response (this message is not sent until the end of the call).

  • Forward HandoverForward Handover, including CELL UPDATE and URA UPDATE, is originated by UE. URA UPDATE procedure is only used for UE under URA_PCH state to process URA reselection, and to check if RRC connection is right. For UE under CELL_FACH and CELL_PCH state cell reselection neededIn specific SA(Service Area)Timer T305 timed out (this timer is defined in system broadcast message)For UE under CELL_PCH and URA_PCH statetransfer data on up link needed (enter CELL_FACH state)upon receiving paging message on PCCH, originate cell update CELL UPDATE process can be used to re-establish unrecoverable errors of RLC entitylosing connection, and to monitor RRC connection state.

  • Cell Update with SRNS relocation

    1.UE sends a RRC message Cell Update to the UTRAN, after having made cell re-selection. Upon reception of a CCCH message from a UE, target RNC allocates a C-RNTI for the UE.2.Controlling target RNC forward the received message (on CCCH) via Uplink Signalling Transfer Indication RNSAP message towards the SRNC. Message includes, besides target RNC-ID, also the allocated C-RNTI, which is to be used as UE identification within the C-RNC, and the D-RNTI. Upon reception of the RNSAP message SRNC decides to perform SRNS Relocation towards the target RNC.3.Serving RNC relocation procedure is executed ,After completing SRNS Relocation, target RNC allocates new S-RNTI for the UE, becoming the new serving RNC.4.Target RNC responds to UE by RRC Cell Update Confirm, including old S-RNTI and SRNC ID as UE identifiers. Message contains also the new S-RNTI, SRNC-ID and C-RNTI.5. UE acknowledges the RNTI reallocation by sending the RRC message UTRAN Mobility Information Confirm.

  • Cell Update via Iur without SRNS relocation

    1.UE sends an RRC message Cell Update to the UTRAN (Target DRNC), after having made cell re-selection.2.Upon reception of a CCCH message from a UE, the target DRNC decodes the SRNC-ID and the S-RNTI. The UE is not registered in the target DRNC, thus the target DRNC allocates C-RNTI and D-RNTI for the UE. The target DRNC forwards the received uplink CCCH message towards the SRNC in the RNSAP Uplink Signalling Transfer Indication message. The Uplink Signalling Transfer message includes also the cell-ID of the cell from which the CCCH message was received, the D-RNC ID and the allocated C-RNTI and D-RNTI.3.Upon reception of the Uplink Signalling Transfer message the SRNC decides not to perform an SRNS Relocation towards the target RNC. The SRNC initialises the UE context in the target RNC with the RNSAP Common Transport Channel Resources Initialisation Request message. The message includes the D-RNTI and the cell identity previously received in the Uplink Signalling Transfer indication message, as well as a request for transport layer address and binding identity if there exists no appropriate Iur transport bearer to be used for the UE.4.The target DRNC sends the transport layer address, binding identity and optionally PHY parameters (FACH code, ) to the SRNC with the RNSAP Common Transport Channel Resources Initialisation Response message 5.If there does not already exist an appropriate Iur transport bearer to be used for the UE, a transport bearer is established from the SRNC.6.The SRNC sends RRC Cell Update Confirm to the UE. The message is sent in the Iur user plane. It will be sent by the target DRNC to the UE on the FACH coupled to the RACH. Subsequent FACH data may be sent on a different FACH if so decided by the target DRNC.7.UE acknowledges the RNTI reallocation by sending the RRC message UTRAN Mobility Information Confirm.8.The SRNC releases the UE context in the source DRNC by sending a Common Transport Channel Resources Release message. The source DRNC releases the D-RNTI.

  • Inter-RNS URA Update via Iur without SRNS relocation

    UETargetRNC5.CCCH: URA Update ConfirmSourceRNC2.Uplink Signaling Transfer IndicationServingRNC[new C-RNTI,D-RNTI, UL message]1.CCCH: URA Update[U-RNTI, URA update cause]RRC-relayRRC3. Decision Not toperform SRNSrelocation RRCRRC-relayRNSAPRNSAP4. Downlink Signaling Transfer RequestRNSAPRNSAP

    1.UE sends a RRC message URA Update to the UTRAN, after having made cell re-selection and URA has changed.2.Upon reception of the message from a UE, Target RNC decodes the RNC ID and the S-RNTI. The UE is not registered in the target RNC (RNC ID and SRNTI unknown), thus RNC allocates C-RNTI and D-RNTI for the UE. The Target RNC forward the received Uu signalling message towards the SRNC by RNSAP Uplink Signalling Transfer Indication message. The message includes also the cell-ID from which the message was received and the allocated C-RNTI and D-RNTI.3.Upon reception of the RNSAP message SRNC decides not to perform an SRNS relocation towards the target RNC. The target RNC become C-RNC while SRNC remains unchanged. 4.SRNC delivers to Target RNC information upon, eventually new, RNTIs via a Downlink Signalling Transfer Request, transporting a URA Update Confirm.5.The URA Update Confirm is forwarded to the UE (via CCCH with new RNTIs) from the target RNC.

  • 6 .ppt4

    Lets discuss some basic notions.UE Working Mode and StateServing RNCDrift RNC and Control RNC Source RNC and Target RNCNotions about AREAWhen a UE is switched on, a public land mobile network (PLMN) is selected and the UE searches for a suitable cell of this PLMN to camp on. The NAS shall provide a list of equivalent PLMNs, if available, that the AS shall use for cell selection and cell reselection.The UE searches for a suitable cell of the chosen PLMN and chooses that cell to provide available services, and tunes to its control channel. This choosing is known as "camping on the cell". The UE will, if necessary, then register its presence, by means of a NAS registration procedure, in the registration area of the chosen cell.If the UE finds a more suitable cell, it reselects onto that cell and camps on it. If the new cell is in a different registration area, location registration is performed .The connected mode is entered when the RRC connection is established. The UE is assigned a Radio Network Temporary Identity (RNTI) to be used as UE identity on common transport channels. Two types of RNTI exist. The Serving RNC allocates an s-RNTI for all UEs having an RRC connection. The combination of s-RNTI and an RNC-ID is unique within a PLMN. c-RNTI is allocated by each Controlling RNC through which UE is able to communicate on DCCH. cRNTI is always allocated by UTRAN when a new UE context is created to an RNC, but the UE needs its c-RNTI only for communicating on common transport channels.The UE leaves the connected mode and returns to idle mode when the RRC connection is released or at RRC connection failure.Within connected mode the level of UE connection to UTRAN is determined by the quality of service requirements of the active radio bearers and the characteristics of the traffic on those bearers.The UE-UTRAN interface is designed to support a large number of UEs using packet data services by providing flexible means to utilize statistical multiplexing. Due to limitations, such as air interface capacity, UE power consumption and network h/w availability, the dedicated resources cannot be allocated to all of the packet service users at all times.Variable rate transmission provides the means that for services of variable rate the data rate is adapted according to the maximum allowable output power.The UE state in the connected mode defines the level of activity associated to the UE. The key parameters of each state are the required activity and resources within the state and the required signalling prior to the data transmission. The state of the UE shall at least be dependent on the application requirement and the period of inactivity.Common Packet Channel (CPCH) uplink resources are available to UEs with an access protocol similar to the RACH. The CPCH resources support uplink packet communication for numerous UEs with a set of shared, contention-based CPCH channels allocated to the cell.The different levels of UE connection to UTRAN are listed below:-No signalling connection existsThe UE is in idle mode and has no relation to UTRAN, only to CN. For data transfer, a signalling connection has to be established.-Signalling connection existsWhen at least one signalling connection exists, the UE is in connected mode and there is normally an RRC connection between UE and UTRAN. The UE position can be known on different levels:-UTRAN Registration Area (URA) levelThe UE position is known on URA level. The URA is a set of cells-Cell levelThe UE position is known on cell level. Different transport channel types can be used for data transfer:-Common transport channels (RACH / FACH, DSCH, CPCH)-Dedicated transport CHannels (DCH)Assuming that there exists an RRC connection, there are two basic families of RRC connection mobility procedures, URA updating and handover. Different families of RRC connection mobility procedures are used in different levels of UE connection (cell level and URA level):-URA updating is a family of procedures that updates the UTRAN registration area of a UE when an RRC connection exists and the position of the UE is known on URA level in the UTRAN;-handover is a family of procedures that adds or removes one or several radio links between one UE and UTRAN when an RRC connection exists and the position of the UE is known on cell level in the UTRAN.

    If there is only few data to be transmitted,there is no need to allocate dedicated channel. Thus UE will be in Cell-FACH. UE in Cell-FACH state is communicating via FACH (downlink) and RACH (uplink) with UTRAN. UE need to monitor the FACH for its relative information because FACHs is shared for all users in the cell.If UE has no data to be transmitted or received, UE will be in Cell-PCH or URA-PCH. In these two states, UE needs to monitor PICH,to receive its paging. UTRAN knows which cell or URA UE is now in. The difference between Cell-PCH and URA-PCH is that UTRAN update UE information only after UE which is in URA-PCH state has roamed to other URA. UTRAN have to update cell information of UE when UE roams to another cell. UE migrates to cell-FACH state to complete the cell update. If there is also no data to be transmitted or received, UE is back to CELL-PCH state after cell update. If the cell update times in a fixed time reach a preset value, UTRAN will let UE migrate to URA-PCH. URA is an area of several cells. It is the same as the CELL-PCH state. UE should migrate to CELL-FACH state to complete the URA update.This is the UE states figure. These states are significant only for UTRAN and UE. They are transparent to CN. Lets focus on the switch between the states. 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 .For each connection between User Equipment and the UTRAN, One RNS is the Serving RNS. When required, Drift RNSs support the Serving RNS by providing radio resources. The role of an RNS (Serving or Drift) is on a per connection basis between a UE and the UTRAN. Then what is CRNC ? CRNC is related to a specific NodeB (or Cell)Now lets see the distinction of Source RNC and Target RNC. First lets understand a notion:SRNC relocation. Source RNC and Target RNC refer to different RNCs during a SRNC Relocation process. Source RNC is the SRNC before SRNC Relocation and Target RNC is the SRNC after SRNC Relocation .

    1,Physical Layer:The physical layer provides transport channels for ATM cells. It adds transport overheads to the ATM cells from the upper ATM layer to form consecutive bit stream. It also extracts the valid ATM cells from the consecutive bit stream received from the physical media and transports them to the ATM layer.The physical layer comprises two sublayers: Transmission Convergence (TC) sublayer and Physical Media (PM) sublayer.

    2,ATM Layer:Asynchronous Transfer Mode (ATM) layer is above the physical layer and communicates with its peer layer by utilizing services provided by the physical layer. The communication unit is cell. The ATM layer is independent of the type of the physical medium, the actual implementation of the physical layer and the type of the services transported. It only identifies and processes cell headers. That is to say, the ATM layer inserts a 5-byte header to the 48-byte cell payload transported from its upper layer, or removes the header from the cells transported from the physical layer and transports it to the upper layer.

    3,AAL2: AAL2 focuses on VBR (low rate) services with specific timing requirements, for example, compression voice service. In this kind of services, the data packets generated are too small to fill a cell, but to wait for enough data packets to fill the cell will surely lead to great delay. Therefore, AAL protocol multiplexes multiple users in one ATM channel, i.e., it fills a cell with the data packets from multiple users and adds a header to each packet to indicate which user it comes from.

    4,AAL5:AAL5 protocol is an AAL protocol especially made for Category-C connection oriented services for the purpose of efficiency improvement on the basis of AAl3/4. AAL5 protocol includes two sublayers: Segment And Reassemble (SAR) and Common part Convergence Sublayer (CPCS). The Segment And Reassemble (SAR) sublayer in the AAL5 segments the CPCS-PDU into 48-byte SAR-PDU without any overheads. Reassembly function is achieved during PDU receiving.

    5,SSCOP:SSCOP provides reliable transmission process for SSCOP applications (SSCF entities) that transmits messages with maximum 64k byte length.

    6,SSCF:The SSCF functions as the adaptation layer of the SSCOP and the upper layer applications. Upper layer applications refer to NBAP, MTP3-B and Signal Transporter (STC). The MTP3-B is used for NNI, which has higher link quality. SAAL is required to support link quality check and to help the MTP3-B with link switchover. But, NBAP is used for User Network Interface (UNI), which has poorer link quality and greater delay. Therefore, SSCF is divided into SSCF-NNI and SSCF-UNI to cater to different upper layer applications.

    7,MTP3-B:Based on Message Transfer Part Layer 3 (MTP3), MTP3-B is the protocol specification aiming at ATM features. As the signaling transport layer, MTP3-B is responsible for transferring signaling messages, managing signaling networks and signaling links. It performs message exchange via the services provided by SAAL.

    8,ALCAP:Access Link Control Application Part (ALCAP), also called Q.AAL2 protocol, complies with ITU-T Q.2630.1 and resides in the user plane of the Iub/Iur/Iu-CS transport network layer with the signaling bearers of SAAL UNI type and MTP3-B type. ALCAP consists of a Q.AAL2 protocol processing layer (one plane) and two STC adaptation layers (the other plane) in which the former plane performs all protocol functions while the latter one adapts primitives and shield bottom-layer differences (SAAL, MTP3-B). The basic function of ALCAP is establishing and releasing AAL2 connection between two SPs. Besides, it also maintains and manages such resources as path, tunnel in the micro cell of the signaling system. The AAL2 connections controlled by ALCAP shall be regarded as the transmission bearer for the control plane and user plane of the radio network layer.

    9,SCCP:Signaling Connection Control Part (SCCP) is used to enhance the functions of Message Transfer Part (MTP). Equivalent to the layer 3 of Open Systems Interconnection (OSI), it implements the packet switching function of virtual circuit and datagram. As the addressing function of MTP only can be used to transmit messages to nodes, only the connectionless message transfer function is provided. While SCCP is able to provide a type of addressing function to identify each SCCP user in a node using DPC and subsystem number (SSN). The SCCP performs network service, routing and management functions. 1,Iu-PS Data Bearer:The structure of Iu-PS user-plane data bearer is shown in slide. Working in IP over ATM (IPoA) bearing mode, the AAL layer takes AAL5 as the ATM adaptation type.

    2,IP:Internet Protocol (IP) provides a globally unified addressing mode to shield the differences between physically network addresses, thus enabling route search. Besides, it also provides a globally unified packet format to shield the differences between network link layers, thus enabling network interconnection.

    3,UDP:Providing connectionless service, User Datagram Protocol (UDP) increases port addresses based on IP to distinguish different applications on a host. For example, the destination port number used by GTP-U is 2152 and the source port number is an arbitrary value distributed by the transmitting end.

    4,GTP-UGPRS Tunnel Protocol User Plane (GTP-U) transmits Iu-PS user-plane data and manages Iu-PS user-plane paths. As 3G supports the transmissions of multiple types of packet data and will further support more types of such data due to the function enhancement in the future, GTP-U adopts a versatile tunnel encapsulation method based on GTP to encapsulate various packet data for transparent transmissions, facilitating the supporting for these data.

    Uu interface is the interface between User Equipment (UE) and UMTS Terrestrial Radio Access Network (UTRAN) and it is the most important interface in the WCDMA system.The radio interface is layered into three protocol layers:-the physical layer (L1);-the data link layer (L2);-network layer (L3).Layer 2 is split into following sublayers: Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP) and Broadcast/Multicast Control (BMC).Layer 3 and RLC are divided into Control (C-) and User (U-) planes. PDCP and BMC exist in the U-plane only.The physical layer offers information transfer services to MAC and higher layers. The physical layer transport services are described by how and with what characteristics data are transferred over the radio interface. An adequate term for this is 'Transport Channel'.

    RLC Functions:-Segmentation and reassembly. This function performs segmentation/reassembly of variable-length upper layer PDUs into/from smaller RLC PDUs. The RLC PDU size is adjustable to the actual set of transport formats.-Transfer of user data. This function is used for conveyance of data between users of RLC services. RLC supports acknowledged, unacknowledged and transparent data transfer. QoS setting controls transfer of user data.-Error correction. This function provides error correction by retransmission (e.g. Selective Repeat, Go Back N, or a Stop-and-Wait ARQ) in acknowledged data transfer mode.-In-sequence delivery of upper layer PDUs. This function preserves the order of upper layer PDUs that were submitted for transfer by RLC using the acknowledged data transfer service. If this function is not used, out-of-sequence delivery is provided.-Duplicate Detection. This function detects duplicated received RLC PDUs and ensures that the resultant upper layer PDU is delivered only once to the upper layer.-Flow control. This function allows an RLC receiver to control the rate at which the peer RLC transmitting entity may send information.-Sequence number check. This function is used in unacknowledged mode and guarantees the integrity of reassembled PDUs and provides a mechanism for the detection of corrupted RLC SDUs through checking sequence number in RLC PDUs when they are reassembled into a RLC SDU. A corrupted RLC SDU will be discarded.-Protocol error detection and recovery. This function detects and recovers from errors in the operation of the RLC protocol.-Ciphering. This function prevents unauthorised acquisition of data. Ciphering is performed in RLC layer for non-transparent RLC mode. -Suspend/resume function. Suspension and resumption of data transfer.The Radio Resource Control (RRC) layer handles the control plane signalling of Layer 3 between the UEs and UTRAN. The RRC performs the following functions:-Broadcast of information provided by the non-access stratum (Core Network). The RRC layer performs system information broadcasting from the network to all UEs. The system information is normally repeated on a regular basis. The RRC layer performs the scheduling, segmentation and repetition. This function supports broadcast of higher layer (above RRC) information. This information may be cell specific or not. As an example RRC may broadcast Core Network location service area information related to some specific cells.- Broadcast of information related to the access stratum. The RRC layer performs system information broadcasting from the network to all UEs. The system information is normally repeated on a regular basis. The RRC layer performs the scheduling, segmentation and repetition. This function supports broadcast of typically cell-specific information.- Paging/notification. The RRC layer can broadcast paging information from the network to selected UEs. Higher layers on the network side can request paging and notification. The RRC layer can also initiate paging during an established RRC connection.-Establishment, re-establishment, maintenance and release of an RRC connection between the UE and UTRAN. The establishment of an RRC connection is initiated by a request from higher layers at the UE side to establish the first Signalling Connection for the UE. The establishment of an RRC connection includes an optional cell re-selection, an admission control, and a layer 2 signalling link establishment. The release of an RRC connection can be initiated by a request from higher layers to release the last Signalling Connection for the UE or by the RRC layer itself in case of RRC connection failure. In case of connection loss, the UE requests re-establishment of the RRC connection. In case of RRC connection failure, RRC releases resources associated with the RRC connection.-Establishment, reconfiguration and release of Radio Bearers. The RRC layer can, on request from higher layers, perform the establishment, reconfiguration and release of Radio Bearers in the user plane. A number of Radio Bearers can be established to an UE at the same time. At establishment and reconfiguration, the RRC layer performs admission control and selects parameters describing the Radio Bearer processing in layer 2 and layer 1, based on information from higher layers.-Assignment, reconfiguration and release of radio resources for the RRC connection. The RRC layer handles the assignment of radio resources (e.g. codes, CPCH channels) needed for the RRC connection including needs from both the control and user plane. The RRC layer may reconfigure radio resources during an established RRC connection. This function includes coordination of the radio resource allocation between multiple radio bearers related to the same RRC connection. RRC controls the radio resources in the uplink and downlink such that UE and UTRAN can communicate using unbalanced radio resources (asymmetric uplink and downlink). RRC signals to the UE to indicate resource allocations for purposes of handover to GSM or other radio systems.- RRC connection mobility functions. The RRC layer performs evaluation, decision and execution related to RRC connection mobility during an established RRC connection, such as handover, preparation of handover to GSM or other systems, cell re-selection and cell/paging area update procedures, based on e.g. measurements done by the UE.-Initial cell selection and re-selection in idle mode. Selection of the most suitable cell based on idle mode measurements and cell selection criteria.-Routing of higher layer PDUs. This function performs at the UE side routing of higher layer PDUs to the correct higher layer entity, at the UTRAN side to the correct RANAP entity.RRC Functions (Continue)- Outer loop power control. The RRC layer controls setting of the target of the closed loop power control.- Control of requested QoS. This function shall ensure that the QoS requested for the Radio Bearers can be met. This includes the allocation of a sufficient number of radio resources.- UE measurement reporting and control of the reporting. The measurements performed by the UE are controlled by the RRC layer, in terms of what to measure, when to measure and how to report, including both UMTS air interface and other systems. The RRC layer also performs the reporting of the measurements from the UE to the network.-Control of ciphering. The RRC layer provides procedures for setting of ciphering (on/off) between the UE and UTRAN. -Integrity protection. This function adds a Message Authentication Code (MAC-I) to those RRC messages that are considered sensitive and/or contain sensitive information. -Initial Configuration for CBSThis function performs the initial configuration of the BMC sublayer.-Allocation of radio resources for CBSThis function allocates radio resources for CBS based on traffic volume requirements indicated by BMC. The radio resource allocation set by RRC (i.e. the schedule for mapping of CTCH onto FACH/S-CCPCH) is indicated to BMC to enable generation of schedule messages. The resource allocation for CBS shall be broadcast as system information.-Configuration for CBS discontinuous receptionThis function configures the lower layers (L1, L2) of the UE when it shall listen to the resources allocated for CBS based on scheduling information received from BMC.

    Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.First of all, the network should be started. Then UE power on. After cell reselection and location registration UE enters idle mode and can call or waits for call. Now if UE receives a paging information, the UE will begin RRC connection establish and enter connected mode. RRC connection establish only setup the connection between UE and UTRAN. The next step of NAS signaling connection establish setup the connection between UTRAN and CN. Then CN processes RAB set up. RAB set up includes synchronous set up and asynchronous set up. The difference will introduce in the back slide. Now UE can begin call. During the call, if UE moves from one cell to another, handover will happen; if the service source rate changes, RAB/RB modification,physical channel reconfiguration and transport channel reconfiguration will happen. After the call, RRC connection release and UE enter idle mode again.Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.Network start process is the System Information Broadcast Flow. First RNC sendsthen NodeB responseNodeB sends system information to UE through BCCH. We can see that nodeb sends system information three times thus to increasing UEs receiving ratio.Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.This is RRC Connection Establishment flow. First UE originate RRC connection setup for registration. SRNC decides to establish RRC connection on common channel, and uses pre-configured common channel resources. Then SRNC sends message of RRCconnection setup to UE. UE response message of RRCconnection setup complete. Thus the flow finishes. This is the NAS Signaling Establishment Flow .The main function of NAS Signaling Establishment Flow is UE changes DT messages with CN, such as Authentication, connection establishment, location registration, etc.In registration process, UE does not use dedicated user plane resources. Instead, it release signaling link directly. First is IU release and then is RRC connection release. Thus registration procedure ends.Introduce the basic signaling procedures from five aspects: Call overall processNetwork start processUE registration processCall process, soft handover and hard handover processConnection mobility management process

    First introduce call overall process.This example shows how paging is performed for a UE in RRC Idle Mode. The UE may be paged for a CS or PS service. Since the UE is in RRC Idle Mode, the location is only known at CN level and therefore paging is distributed over a defined geographical area This can occur in case of two core network domains, with the mobility management independent of each other. Two possible solutions exists:The UTRAN coordinates the paging request with the existing RRC connection.The UE coordinates the paging request with the existing RRC connection. 1.The UE initiates set-up of an RRC connection by sending RRC Connection Request message on CCCH.Parameters: Initial UE Identity, Establishment cause.2.The SRNC decides to use a DCH for this RRC connection, allocates U-RNTI and radio resources for the RRC connection. When a DCH is to be set-up, NBAP message Radio Link Setup Request is sent to Node B.Parameters: Cell id, Transport Format Set, Transport Format Combination Set, frequency, UL scrambling code (FDD only), Time Slots (TDD only), User Codes (TDD only), Power control information.3.Node B allocates resources, starts PHY reception, and responds with NBAP message Radio Link Setup Response.Parameters: Signalling link termination, Transport layer addressing information (AAL2 address, AAL2 Binding Identity) for the Iub Data Transport Bearer.4.SRNC initiates set-up of Iub Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to the DCH. The request for set-up of Iub Data Transport bearer is acknowledged by Node B.5./6.The Node B and SRNC establish synchronism for the Iub and Iur Data Transport Bearer by means of exchange of the appropriate DCH Frame Protocol frames Downlink Synchronisation and Uplink Synchronisation. Then Node B starts DL transmission.7.Message RRC Connection Setup is sent on CCCH from SRNC to UE.Parameters: Initial UE Identity, U-RNTI, Capability update Requirement, Transport Format Set, Transport Format Combination Set, frequency, DL scrambling code (FDD only), Time Slots (TDD only), User Codes (TDD only), Power control information.8.Node B achieves uplink sync and notifies SRNC with NBAP message Radio Link Restore Indication.9.Message RRC Connection Setup Complete is sent on DCCH from UE to SRNC.Parameters: Integrity information, ciphering information, UE radio access capability. 1.RRC Connection is established (see 7.3.1 or 7.3.2).2.UE sends RRC Initial Direct Transfer to SRNC.Parameters: Initial NAS Message (could for a GSM based CN be e.g. CM Service Request, Location Update Request etc.) CN node indicator (it indicates the correct CN node into which the NAS message shall be forwarded).3.SRNC initiates signalling connection to CN, and sends the RANAP message Initial UE Message.Parameters: NAS PDU (could for a GSM based CN be e.g. CM Service Request, Location Update Request etc.), CN domain indicator (indicating the CN domain towards which this message is sent). 1. CN initiates establishment of the radio access bearer with RANAP message Radio Access Bearer Assignment Request.Parameters: Radio Access Bearer parameters, User Plane Mode, Transport Address, Iu Transport Association.SRNC initiates set-up of Iu Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iu Data Transport Bearer to the Radio Access Bearer (this step is not required towards PS domain). SRNC requests its Node B to prepare establishment of DCH to carry the radio access bearer (Radio Link Reconfiguration Prepare).Parameters: Transport Format Set, Transport Format Combination Set, Power control information, Time Slots (TDD only), User Codes (TDD only). Node B allocates resources and notifies SRNC that the preparation is ready (Radio Link Reconfiguration Ready).Parameters: Transport layer addressing information (AAL2 address, AAL2 Binding Id) for Iub Data Transport Bearer. SRNC initiates setup of Iub Data Transport Bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to DCH. NBAP message Radio Link Reconfiguration Commit is sent from SRNC to Node B. RRC message Radio Access Bearer Setup is sent by SRNC to UE.Parameters: Transport Format Set, Transport Format Combination Set, UE sends RRC message Radio Access Bearer Setup Complete to SRNC.9.SRNC sends RANAP message Radio Access Bearer Assignment Response to CN. 1. CN initiates establishment of the radio access bearer with RANAP message Radio Access Bearer Assignment Request.Parameters: Radio Access Bearer parameters, User Plane Mode, Transport Address, Iu Transport Association.SRNC initiates set-up of Iu Data Transport bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iu Data Transport Bearer to the Radio Access Bearer (this step is not required towards PS domain). SRNC requests its Node B setup a new DCH in the existing Radio Link sending the RL Reconfiguration Request message.Parameters: Bearer ID, Transport Format Set, Transport Format Combination Set, Power control information. Node B allocates resources and notifies SRNC that the setup is sending the RL Reconfiguration Response.Parameters: Transport layer addressing information (AAL2 address, AAL2 Binding Id) for Iub Data Transport Bearer. SRNC initiates setup of Iub Data Transport Bearer using ALCAP protocol. This request contains the AAL2 Binding Identity to bind the Iub Data Transport Bearer to DCH. RRC message Radio Access Bearer Setup is sent by SRNC to UE.Parameters: Transport Format Set, Transport Format Combination Set, UE sends RRC message Radio Access Bearer Setup Complete to SRNC.8.SRNC sends RANAP message Radio Access Bearer Assignment Response to CN. RNC requests its Node B to prepare reconfiguration of DCH (Radio Link Reconfiguration Prepare).Parameters: Transport Format Set, Transport Format Combination Set, Power control information Node B allocates resources and notifies SRNC that the reconfiguration is ready (Radio Link Reconfiguration Ready