S1 Interface

S1 interface is between the eNB (eNodeB) and the MME (Mobility Management Entity).

Overview

S1-MME interface is between the eNB (eNodeB) and the MME (Mobility Management Entity). It uses S1AP over SCTP transport protocol.

Network Diagram

Messages

  • HANDOVER NOTIFY
  • E-RAB RELEASE INDICATION
  • PAGING
  • INITIAL UE MESSAGE
  • DOWNLINK NAS TRANSPORT
  • UPLINK NAS TRANSPORT
  • NAS NON DELIVERY INDICATION
  • ERROR INDICATION
  • UE CONTEXT RELEASE REQUEST
  • DOWNLINK S1 CDMA2000 TUNNELLING
  • UPLINK S1 CDMA2000 TUNNELLING
  • UE CAPABILITY INFO INDICATION
  • eNB STATUS TRANSFER
  • MME STATUS TRANSFER
  • DEACTIVATE TRACE
  • TRACE START
  • TRACE FAILURE INDICATION
  • LOCATION REPORTING CONTROL
  • LOCATION REPORTING FAILURE INDICATION
  • LOCATION REPORT
  • OVERLOAD START
  • OVERLOAD STOP
  • eNB DIRECT INFORMATION TRANSFER
  • MME DIRECT INFORMATION TRANSFER
  • eNB CONFIGURATION TRANSFER
  • MME CONFIGURATION TRANSFER
  • CELL TRAFFIC TRACE
  • DOWNLINK UE ASSOCIATED LPPA TRANSPORT
  • UPLINK UE ASSOCIATED LPPA TRANSPORT
  • DOWNLINK NON UE ASSOCIATED LPPA TRANSPORT
  • UPLINK NON UE ASSOCIATED LPPA TRANSPORT
  • PWS RESTART INDICATION
  • REROUTE NAS REQUEST
  • PWS FAILURE INDICATION
  • CONNECTION ESTABLISHMENT INDICATION
  • NAS DELIVERY INDICATION
  • RETRIEVE UE INFORMATION
  • UE INFORMATION TRANSFER
  • eNB CP RELOCATION INDICATION
  • MME CP RELOCATION INDICATION
  • SECONDARY RAT DATA USAGE REPORT

Call Flows

Standards

  • 3GPP TS 36.413