1、LTE层3信令流程概要和States Machine,E-UTRAN 控制面协议栈,GTP-C,UDP,L2,L1,IP,PDN/S-GW,29.274,RRC 信令流程概要 (Spec 36.331),5.2 System information Connection control 5.3.2 Paging 5.3.3 RRC connection establishment 5.3.4 Initial security activation 5.3.5 RRC connection reconfiguration 5.3.6 Counter check 5.3.7 RRC connect
2、ion re-establishment 5.3.8 RRC connection release 5.3.9 RRC connection release requested by upper layers 5.3.10 Radio resource configuration 5.3.11 Radio link failure related actions 5.3.12 UE actions upon leaving RRC_CONNECTED 5.3.13 UE actions upon PUCCH/ SRS release request 5.4 Inter-RAT mobility
3、 5.5 Measurements Other 5.6.1 DL information transfer 5.6.2 UL information transfer 5.6.3 UE capability transfer 5.6.4 CSFB to 1x Parameter transfer,NAS EPS MM 信令流程概要 (Spec 24.301),Common procedures 5.4.1 GUTI reallocation procedure 5.4.2 Authentication procedure 5.4.3 Security mode control procedur
4、e 5.4.4 Identification procedure 5.4.5 EMM information procedure Specific procedures 5.5.1 Attach procedure5.5.1.2 Attach procedure for EPS services5.5.1.3 Combined attach procedure for EPS services and non-EPS services 5.5.2 Detach procedure5.5.2.2 UE initiated detach procedure5.5.2.3 Network initi
5、ated detach procedure 5.5.3 Tracking area updating procedure 5.5.3.2 Normal and periodic tracking area updating procedure5.5.3.3 Combined tracking area updating procedure Connection management (ECM) procedures 5.6.1 Service request procedure 5.6.2 Paging procedure 5.6.3 Transport of NAS messages pro
6、cedure 5.6.4 Generic transport of NAS messages procedure,Network initiated ESM procedures(Procedures related to EPS bearer contexts) 6.4.1 Default EPS bearer context activation procedure 6.4.2 Dedicated EPS bearer context activation procedure 6.4.3 EPS bearer context modification procedure 6.4.4 EPS
7、 bearer context deactivation procedure UE requested ESM procedures(Transaction related procedures) 6.5.1 UE requested PDN connectivity procedure 6.5.2 UE requested PDN disconnect procedure 6.5.3 UE requested bearer resource allocation procedure 6.5.4 UE requested bearer resource modification procedu
8、re Miscellaneous procedures 6.6.1.2 ESM information request procedure 6.6.1.3 Exchange of protocol configuration options in other messages 6.6.2 Notification procedure,NAS EPS SM 信令流程概要 (Spec 24.301),S1-AP 信令流程概要 Class 1 (Spec 36.413),Class 1: Elementary Procedures with response (success and/or fail
9、ure).,S1-AP 信令流程概要 Class 2 (Spec 36.413),Class 2: Elementary Procedures without response,RRC 状态 (Spec 36.331 4.2.1),RRC_IDLE:A UE specific DRX may be configured by upper layers.UE controlled mobility;The UE: Monitors a Paging channel to detect incoming calls, system information change, and for ETWS
10、capable UEs, ETWS notification; Performs neighbouring cell measurements and cell (re-)selection; Acquires system information.,RRC_CONNECTED: Transfer of unicast data to/from UE. At lower layers, the UE may be configured with a UE specific DRX. Network controlled mobility, i.e. handover and cell chan
11、ge order with optional network assistance (NACC) to GERAN; The UE: Monitors a Paging channel and/ or System Information Block Type 1 contents to detect system information change, and for ETWS capable UEs, ETWS notification; Monitors control channels associated with the shared data channel to determi
12、ne if data is scheduled for it; Provides channel quality and feedback information; Performs neighbouring cell measurements and measurement reporting; Acquires system information.,RRC SRB 定义(Spec 36.331 4.2.2),4.2.2 Signalling radio bearers “Signalling Radio Bearers“ (SRBs) are defined as Radio Beare
13、rs (RB) that are used only for the transmission of RRC and NAS messages. More specifically, the following three SRBs are defined: - SRB0 is for RRC messages using the CCCH logical channel; - SRB1 is for RRC messages (which may include a piggybacked NAS message) as well as for NAS messages prior to t
14、he establishment of SRB2, all using DCCH logical channel; SRB2 is for NAS messages, using DCCH logical channel. SRB2 has a lower-priority than SRB1 and is always configured by E-UTRAN after security activation.In downlink piggybacking of NAS messages is used only for one dependant (i.e. with joint s
15、uccess/ failure) procedure: bearer establishment/ modification/ release. In uplink NAS message piggybacking is used only for transferring the initial NAS message during connection setup.NOTE: The NAS messages transferred via SRB2 are also contained in RRC messages, which however do not include any R
16、RC protocol control information. Once security is activated, all RRC messages on SRB1 and SRB2, including those containing NAS or non-3GPP messages, are integrity protected and ciphered by PDCP. NAS independently applies integrity protection and ciphering to the NAS messages.,Initial NAS messages ar
17、e: - ATTACH REQUEST; - DETACH REQUEST; - TRACKING AREA UPDATE REQUEST; - SERVICE REQUEST; and EXTENDED SERVICE REQUEST.Spec 24.301 5.3.1.1,RRC 状态 (Spec 36.300),RRC_IDLE: -PLMN selection; -DRX configured by NAS; -Broadcast of system information; -Paging; -Cell re-selection mobility; -The UE shall hav
18、e been allocated an id which uniquely identifies the UE in a tracking area; -No RRC context stored in the eNB,RRC_CONNECTED: - UE has an E-UTRAN-RRC connection; - UE has context in E-UTRAN; - E-UTRAN knows the cell which the UE belongs to; - Network can transmit and/or receive data to/from UE; - Net
19、work controlled mobility (handover and inter-RAT cell change order to GERAN with NACC); - Neighbour cell measurements; - At PDCP/RLC/MAC level: - UE can transmit and/or receive data to/from network; - UE monitors control signalling channel for shared data channel to see if any transmission over the
20、shared data channel has been allocated to the UE; - UE also reports channel quality information and feedback information to eNB; - DRX period can be configured according to UE activity level for UE power saving and efficient resource utilization. This is under control of the eNB.,RRC Connection (Sub
21、-)States for UE,Initial state Power On System Acquisition,Idle State Cell (re-)selection Measurements Paging,Connected state,Limited connectivity No user plane No HO No Security,Ready for full connectivity Security,Fully Connected User plane HO Security,Release,Conn Request,Conn Failure,SecurityActi
22、vation,SecurityFailure,Reconfiguration,Connection Re-establishment,Failure,Successful connection re-establishment,Re-establishment Failure,EMM main states in the UE (Spec 24.301 5.1.3.2.2.7),EMM main states in the MME (Spec 24.301 5.1.3.4.4),EPS Connection Management (ECM)状态 (Spec 23.401),4.6.3.1 EC
23、M-IDLE A UE is in ECM-IDLE state when no NAS signalling connection between UE and network exists. In ECM-IDLE state, a UE performs cell selection/reselection according to TS 36.304 34 and PLMN selection according to TS 23.122 10. There exists no UE context in E-UTRAN for the UE in the ECM-IDLE state
24、. There is no S1_MME and no S1_U connection for the UE in the ECM-IDLE state. In the EMM-REGISTERED and ECM-IDLE state, the UE shall: -perform a tracking area update if the current TA is not in the list of TAs that the UE has received from the network in order to maintain the registration and enable
25、 the MME to page the UE; -perform the periodic tracking area updating procedure to notify the EPC that the UE is available; -perform a tracking area update if the RRC connection was released with release cause “load balancing TAU required“; -perform a tracking area update when the UE reselects an E-
26、UTRAN cell and the UEs TIN indicates “P-TMSI“; -perform a tracking area update for a change of the UEs Core Network Capability information or the UE specific DRX parameter; -perform a tracking area update when the UE manually selects a CSG cell, and the CSG ID of that cell is absent from both the UE
27、s Allowed CSG list and the UEs Operator CSG list; -answer to paging from the MME by performing a service request procedure; -perform the service request procedure in order to establish the radio bearers when uplink user data is to be sent. The UE and the MME shall enter the ECM-CONNECTED state when
28、the signalling connection is established between the UE and the MME. Initial NAS messages that initiate a transition from ECM-IDLE to ECM-CONNECTED state are Attach Request, Tracking Area Update Request, Service Request or Detach Request. When the UE is in ECMIDLE state, the UE and the network may b
29、e unsynchronized, i.e. the UE and the network may have different sets of established EPS bearers. When the UE and the MME enter the ECMCONNECTED state, the set of EPS Bearers is synchronized between the UE and network. 4.6.3.2 ECM-CONNECTED The UE location is known in the MME with an accuracy of a s
30、erving eNodeB ID. The mobility of UE is handled by the handover procedure. The UE performs the tracking area update procedure when the TAI in the EMM system information is not in the list of TAs that the UE registered with the network, or when the UE handovers to an EUTRAN cell and the UEs TIN indic
31、ates “P-TMSI“. For a UE in the ECM-CONNECTED state, there exists a signalling connection between the UE and the MME. The signalling connection is made up of two parts: an RRC connection and an S1_MME connection. The UE shall enter the ECM-IDLE state when its signalling connection to the MME has been
32、 released or broken. This release or failure is explicitly indicated by the eNodeB to the UE or detected by the UE. The S1 release procedure changes the state at both UE and MME from ECM-CONNECTED to ECM-IDLE. NOTE 1: The UE may not receive the indication for the S1 release, e.g. due to radio link e
33、rror or out of coverage. In this case, there can be temporal mismatch between the ECM-state in the UE and the ECM-state in the MME. After a signalling procedure, the MME may decide to release the signalling connection to the UE, after which the state at both the UE and the MME is changed to ECM-IDLE
34、. NOTE 2: There are some abnormal cases where the UE transitions to ECM-IDLE. When a UE changes to ECMCONNECTED state and if a radio bearer cannot be established, or the UE cannot maintain a bearer in the ECM-CONNECTED state during handovers, the corresponding EPS bearer is deactivated.,EPS Connection Management (ECM)状态 (Spec 23.401 4.6.4),RRC ECM EMM状态关系,EPS Session Management (ESM)状态 (Spec 24.301),
