S1 Interface connects the eNB and the MME

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

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• 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