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white_Noise
2011-11-01, 09:14 PM
Dears,

I know my question might be basic, but I don't have the time to read the documents for an answer.

Can a UE establis a RAB without establishing an RRC? would be that in case of handover?

jan74
2011-11-01, 09:55 PM
Dears,

I know my question might be basic, but I don't have the time to read the documents for an answer.

Can a UE establis a RAB without establishing an RRC? would be that in case of handover?


You always have to have an RRC active. You dont have to setup a new RRC all the time but you have to have one to setup a RAB. If you have an RRC, you can setup several RABs. But a RAB without RRC is not possible.

white_Noise
2011-11-01, 11:44 PM
You always have to have an RRC active. You dont have to setup a new RRC all the time but you have to have one to setup a RAB. If you have an RRC, you can setup several RABs. But a RAB without RRC is not possible.

but I'm asking cause I'm seeing cases where cells have RAB est attempts and Rab est success with zero RRC attempts, that was the trigger for my question

jan74
2011-11-01, 11:48 PM
but I'm asking cause I'm seeing cases where cells have RAB est attempts and Rab est success with zero RRC attempts, that was the trigger for my question

2 possibilities that I can think about....

1. Sleeping Cell, allowing Handovers in but no call setups. I have seen this in the past.

2. Counter problems (unlikely but possible)

Get the site reset and see what happens....

white_Noise
2011-11-01, 11:52 PM
2 possibilities that I can think about....

1. Sleeping Cell, allowing Handovers in but no call setups. I have seen this in the past.

2. Counter problems (unlikely but possible)

Get the site reset and see what happens....

Already though of this, but the break down for the RRC shows some RRC attempts for PS, zero RRC attempts for CS, and RAB Est success for CS !!

jan74
2011-11-02, 10:10 PM
Already though of this, but the break down for the RRC shows some RRC attempts for PS, zero RRC attempts for CS, and RAB Est success for CS !!

You need to get either a drive test done or the site reset. It sounds like the site is in some way sleeping. Sleeping cells were apparently resolved a few years ago but I have seen different versions of it. What vendor is it?

cococrunch
2012-04-04, 06:52 PM
Is this cell a second carrier?
It might be that the RRC is setup in F1 and then directed to F2 to perform the RAB Estab.

ritgail
2012-04-05, 12:44 AM
Dears,

I know my question might be basic, but I don't have the time to read the documents for an answer.

Can a UE establis a RAB without establishing an RRC? would be that in case of handover?

Hi,

Basic of RRC and RAB may be pointed out like:

1. RRC- To get a radio resource from the UTRAN.

2. RAB- to get a resource from the core network(PS/CS) through UTRAN.

1. RRC- goes through always 3 steps:

UL RRC setup request- including the cause
DL RRC-Setup
UL RRC Setup Complete

Followed by measurement control information in the DL.

2. After the RRC is established UTRAN conveys the CN about the UE. Then after authentication/security mode is passed by the UE:

CN request UTRAN for RAB according to the requirement of the service requested by the UE.

So RAB establishment comes much later after RRC, and without RRC no RAB would be established.

In your case, "RRC process(all the three steps)" may have completed in a way where UE has done some cell re selection in the process itself. Means sometimes it happens when there is RRC setup completion rate of cell may go above 100%, this happens when UE does a cell reselection in the RRC request itself. search for RRC success rate>100%.


reselection from f1 to f2, in the RRC process, do anybody have document?

AMR 12.2, CS call RAB without RRC. Ok. I dont think there is way to handover cs call from GSM to UMTS for voice call!?

If you have troubleshooted the problem, please let me know.

auto_art
2012-04-05, 12:32 PM
Dears,

I know my question might be basic, but I don't have the time to read the documents for an answer.

Can a UE establis a RAB without establishing an RRC? would be that in case of handover?

yeaah it can..i raise query to E//

they come up with this reply.


Once RAB is assigned for a cell and suppose after sometime handover occurred , in such case RAB will remain the same it will not assign again because RAB assignment is done through RNC and core network part ,
So in case of handover radio bearer changes on Node B level not from RNC and Core network . that’s why some traffic is shown on those cells which are having RAB Setup Success Rate R99 is zero