3 Definitions and abbreviations
36.4133GPPEvolved Universal Terrestrial Radio Access Network (E-UTRAN)Release 17S1 Application Protocol (S1AP)TS
3.1 Definitions
For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply.
A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].
ACL functionality: A functionality controlling the access to network nodes. In case of Access Control Lists (ACL) functionality is applied in a network node the network node may only accept connections from other peer network nodes once the source addresses of the sending network node is already known in the target node.
CSG Cell: an E-UTRAN cell broadcasting a CSG indicator set to true and a CSG identity. This cell operates in Closed Access Mode as defined in TS 22.220 [28].
DAPS Handover: as defined in TS 36.300 [14].
DCN-ID: DCN identity identifies a specific decicated core network (DCN).
Dual Connectivity: as defined in TS 36.300 [14].
Elementary Procedure: S1AP consists of Elementary Procedures (EPs). An Elementary Procedure is a unit of interaction between eNBs and the EPC. These Elementary Procedures are defined separately and are intended to be used to build up complete sequences in a flexible manner. If the independence between some EPs is restricted, it is described under the relevant EP description. Unless otherwise stated by the restrictions, the EPs may be invoked independently of each other as standalone procedures, which can be active in parallel. The usage of several S1AP EPs together or together with EPs from other interfaces is specified in stage 2 specifications (e.g., TS 23.401 [11] and TS 36.300 [14]).
An EP consists of an initiating message and possibly a response message. Two kinds of EPs are used:
– Class 1: Elementary Procedures with response (success and/or failure).
– Class 2: Elementary Procedures without response.
For Class 1 EPs, the types of responses can be as follows:
Successful:
– A signalling message explicitly indicates that the elementary procedure successfully completed with the receipt of the response.
Unsuccessful:
– A signalling message explicitly indicates that the EP failed.
– On time supervision expiry (i.e., absence of expected response).
Successful and Unsuccessful:
– One signalling message reports both successful and unsuccessful outcome for the different included requests. The response message used is the one defined for successful outcome.
Class 2 EPs are considered always successful.
eNB UE S1AP ID: as defined in TS 36.401 [2].
Hybrid Cell: an E-UTRAN cell broadcasting a CSG indicator set to false and a CSG identity. This cell operates in Hybrid Access Mode as defined in TS 22.220 [28].
MME UE S1AP ID: as defined in TS 36.401 [2].
E-RAB: as defined in TS 36.401 [2].
NOTE 1: The E-RAB is either a default E-RAB or a dedicated E-RAB.
E-RAB ID: the E-RAB ID uniquely identifies an E-RAB for one UE.
NOTE 2: The E-RAB ID remains unique for the UE even if the UE-associated logical S1-connection is released during periods of user inactivity.
Data Radio Bearer: the Data Radio bearer transports the packets of an E-RAB between a UE and an eNB. There is a one-to-one mapping between the E-RAB and the Data Radio Bearer.
Secondary Cell Group: as defined in TS 36.300 [14].
UE-associated signalling: When S1-AP messages associated to one UE uses the UE-associated logical S1-connection for association of the message to the UE in eNB and EPC.
UE-associated logical S1-connection: The UE-associated logical S1-connection uses the identities MME UE S1AP ID and eNB UE S1AP ID according to definition in TS 23.401 [11]. For a received UE associated S1-AP message the MME identifies the associated UE based on the MME UE S1AP ID IE and the eNB identifies the associated UE based on the eNB UE S1AP ID IE. The UE-associated logical S1-connection may exist before the S1 UE context is setup in eNB.
3.2 Abbreviations
For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply.
An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905 [1].
ACL Access Control List
ARPI Additional RRM Policy Index
BBF Broadband Forum
CCO Cell Change Order
CDMA Code Division Multiple Access
CID Cell-ID (positioning method)
CIoT Cellular Internet of Things
CS Circuit Switched
CSG Closed Subscriber Group
CN Core Network
DAPS Dual Active Protocol Stacks
DCN Dedicated Core Network
DL Downlink
eAN evolved Access Network
ECGI E-UTRAN Cell Global Identifier
E-CID Enhanced Cell-ID (positioning method)
eHRPD evolved High Rate Packet Data
eNB E-UTRAN NodeB
EN-DC E-UTRA-NR Dual Connectivity
EP Elementary Procedure
EPC Evolved Packet Core
EPS Evolved Packet System
E-RAB E-UTRAN Radio Access Bearer
E-SMLC Evolved Serving Mobile Location Centre
E-UTRAN Evolved UTRAN
GBR Guaranteed Bit Rate
GNSS Global Navigation Satellite System
GUMMEI Globally Unique MME Identifier
GTP GPRS Tunnelling Protocol
HFN Hyper Frame Number
HRPD High Rate Packet Data
IAB Integrated Access and Backhaul
IE Information Element
IMEISV International Mobile station Equipment Identity and Software Version number
IoT Internet of Things
LAA Licensed-Assisted Access
L-GW Local GateWay
LHN Local Home Network
LHN ID Local Home Network ID
LIPA Local IP Access
LPPa LTE Positioning Protocol Annex
LWA LTE-WLAN Aggregation
LWIP LTE WLAN Radio Level Integration with IPsec Tunnel
MBSFN Multimedia Broadcast multicast service Single Frequency Network
MDT Minimization of Drive Tests
MME Mobility Management Entity
MTSI Multimedia Telephony Service for IMS
NAS Non Access Stratum
NB-IoT Narrowband IoT
NNSF NAS Node Selection Function
NTN Non Terrestrial Networks
OTDOA Observed Time Difference of Arrival
PDCP Packet Data Convergence Protocol
PLMN Public Land Mobile Network
ProSe Proximity Services
PS Packet Switched
PSCell Primary SCell
PWS Public Warning System
RACS Radio Capability Signalling optimization
RRC Radio Resource Control
RIM RAN Information Management
QMC QoE Measurement Collection
QoE Quality of Experience
SCTP Stream Control Transmission Protocol
SCG Secondary Cell Group
S-GW Serving GateWay
SN Sequence Number
SIPTO Selected IP Traffic Offload
SIPTO@LN Selected IP Traffic Offload at the Local Network
SSID Service Set Identifier
S-TMSI S-Temporary Mobile Subscriber Identity
SUL Supplementary Uplink
TAC Tracking Area Code
TAI Tracking Area Identity
TEID Tunnel Endpoint Identifier
UE User Equipment
UE-AMBR UE-Aggregate Maximum Bitrate
UL Uplink
UTDOA Uplink Time Difference of Arrival
V2X Vehicle-to-Everything
WUS Wake Up Signal