Information interaction during LTE ue attach

Note: Information interactions listed in the following table, including all information related to ENB (UE <-> ENB <-> EPC)

 

MSG name	Entities	Comment
S1 SETUP Request	ENB-> NW	S1ap setup
S1 setup response	NW-> ENB
MiB, sib1, sibx	ENB-> ues	Broadcast info
Msg1	UE-> ENB	Preamble
Msg2	ENB-> UE	With RA-RNTI
Msg3	UE-> ENB	TM data (RRC conn request)
DL data	ENB-> UE	Copied from msg3 48B
RRC connection setup	ENB-> UE	TM Data ccch
RRC connection setup complete	UE-> ENB	Am data (include NAS attach request)
S1ap: NAS initial ue message	ENB-> NW	Pass the NAS info to Mme
S1ap: initial context SETUP Request	NW-> ENB	Include E-RAB, ue radio capability IE and etc. Attach accept
RRC: uecapabilityenquiry	ENB-> UE	AM: Enquiry Ra capability for specific rat (E-UTRA)
RRC: uecapabilityinformation	UE-> ENB	AM: known by rat only
S1: ue capability info indication	ENB-> Mme	Forward ue's capability info
RRC: securitymodecommand	ENB-> UE	Set securityconfigsmc
RRC: securitymodecomplete	UE-> ENB	To confirm the security setting
RRC: Connection Reconfiguration	ENB-> UE	Nas pdu from initial context Setup request to establish DRB
RRC connection reconfiguration complete	UE-> ENB	To confirm the connection Reconfiguration
S1ap: initial context setup response	ENB-> NW	E-RAB Setup & failed setup list.
RRC: ulinformationtransfer	UE-> ENB	NAS or non-3GPP Info (attach complete)
S1 AP: ul NAS transport	ENB-> Mme	Forward ul info Transfer