When VoLTE Call (QCI1-2-5) and Data Session (QCI6-9) established in LTE, at which point allocation of QCI done?
After RRC and eRAB establishment, dedicated bearer will be established?
As per my understanding initially when UE turned ON, default internet bearers (QCI6-9) and IMS EPS (QCI-5) bearers have been established, which means initially both will get connected there will be no segregation.
After that SIP/IMS registration performed.
When user makes a requests for any types of service network:
• It automatically assigns identifier: QCI (4G QoS Identifier) for each user service with the required QoS (Quality of Service).
• Further it change technical parameters of the 4G network to fulfill requirements of each assigned QCI which comes after the RRC and RAB setup.
• Access Failure will come into picture (if any) before RRC and RAB setup.
• So, to filter on VoLTE/non VoLTE is not relevant here.
Can any one confirm is that above is valid?
I don’t think I understand your question very well.
“…which means initially both will get connected there will be no segregation” - there is segregation.
Any IMS signalling traffic goes on QCI5 and all rest goes on other internet facing default bearer.
I simple just wanted to understand when QCI1 will be assigned for VOLTE call?
I mean at which stage of call flow.
What do you mean by “It”. what happens is, mobile OS knows which traffic needs to be sent on which Qci. UE receives list of IP filters and based on those filter traffic is sent on specific QCIs.
See above.
Access failure for RRC and RAB mean different. an RRC connected UE can have QCI-1 RAB access failure.
Not sure what you mean.
Go through this blog. All for parts. By the end you will/should understand how this all 4 parts:
When INVITE is received by P-CSCF and then P-CSCF will communicate with PCRF and PCRF will communicate with PGW for creating Dedicated bearer with QCI 1, PGW sends create bearer to SGW and then SGW to MME , then MME sends e-RAB setup request to eNB.
Wow great dear! That’s a very extremely detailed one, thanks. It made all points clear 
That helped me alot to clear my confusion. Thanks alot!