DL-EMM Detach Request / Type of detach: re-attach required

[rosan]

Hi Guys,

I can see this message in the middle of a drive log sent from MME. What is the cause for this?

Thanks

[sak2e]

what message?

i can't see it on body email

[rosan]

000772 01:20:11.840 Secured L3 DL EMM Detach Request DL DL-DCCH DLInformationTransfer

Elapsed Time: 20.840

RRC Message:

Channel type: 5, Dir: 1, Data Len: 12 bytes

LTE_Uu_RRC: DL_DCCH_Message

- . .message:- c1:- dlInformationTransfer

- . . . . .rrc-TransactionIdentifier: 2

- . . . . .criticalExtensions:- c1:- dlInformationTransfer-r8

- . . . . . . . .dedicatedInfoType:- dedicatedInfoNAS



Security Header Type: Security protected NAS message: Integrity protected and ciphered

Authentication Code: 0xd3 0x49 0xd5 0xf3, Sequence Number: 3

Secured NAS message:

Integrity protected and ciphered message, content: [0x 07 45 01]

Security Header Type: Plain NAS message, not security protected,

Protocol discriminator: EPS Mobility Managment

Message Type: Detach Request

Type of detach: re-attach required

Device timestamp: 1143771611746250

Sent from my GT-I9507 using Forum Fiend v1.3.3.

[oswe]

this is a comment ive found somewhere:

"I'm testing a live MME, In case S1 intra ENB Handover, after UE moved to target ENB (Handover success) then UE not send TAU (Tracking Area Update) to live MME. next, MME will send Detach Request to UE with type is re_attach_required, EMM_cause = implicitly_detached.
I just meet that event only one time and save to log, so I think it's possible to trigger live NW scenario, but I don't know how to trigger that event again ...!
Do you have some ideal about that way ? maybe I forgot something."

are you able to monitor neighbor behavior ? i mean are you entering some area ?
do you have access to counters with the cause for disconnection ? i think it´s easier than a mobile log

[rosan]

Why does S1 handover required for intra-eNodeB? I don't think for intra or inter eNodeB S1 handover UE need to send TAU after the handover until it is in same TAC.

[sak2e]

Yeap..
@Oswe:
can you explain why S1 handover require for intra-enodeB, is there any spesific trial on your network?