If the UE initiated ATTACH REQUEST cannot be accepted by the network, the MME shall send an ATTACH REJECT message to the UE including an appropriate EMM cause value
If the attach procedure fails due to a Default EPS bearer Setup Failure or an ESM procedure failure or operator determined barring is applied on Default EPS Bearer Context Activation during attach procedure, the MME shall combine the ATTACH REJECT message with a PDN CONNECTIVITY REJECT message contained in the ESM Message Container IE. In this case the EMM Cause value in the ATTACH REJECT message shall be set to #19 "ESM failure"
If the attach request is rejected due to NAS level congestion control, the network shall set the EMM cause value to #22 "congestion" and optionally assigns a back-off timer T3346
Reference: 3GPP TS 24.301
Example: ATTACH REJECT Message
HI,
ReplyDeletecan you please explain what is ESM failure means?
ESM failure observed due to data ==== emm_attach_reject
Deletecause_value = 19 (0x13) (ESM failure)
pdn_connectivity_rej
esm_cause
esm_cause = 27 (0x1b) (Unknown or missing APN)
nice sun glasses!
ReplyDeleteThis comment has been removed by a blog administrator.
DeleteSo in which RRC msg this attach req will be embedded and sent again after the back off time?
ReplyDeleteShould rrc stay in connected mode after getting attach reject?
as per my understanding after attach reject eNB release the RRC connection.
DeleteWhat will UE do after getting attach reject?
ReplyDeleteif the UE attach reject no action needed from UE side, you can check your P-GW side,
DeleteUE again trigger attach request with the T3411 time start
ReplyDelete