LTE: What is the purpose of sending Bearer Resource Allocation Request to MME from UE ?

Question

Bearer Resource Allocation Request with qci=x send from UE to Network. but that qci is already present in one of dedicated bearer then pgw is sending reject w.r.t Bearer Resource Allocation Request .From MME side we are sending BEARER RESOURCE ALLOCATION REJECT with cause " request rejected by Serving GW or PDN GW ". Then again UE is triggering BEARER RESOURCE ALLOCATION REQUEST.

we tried with cause " insufficient resources with timer value " then also UE is triggering BEARER RESOURCE ALLOCATION REQUEST.

so , how we can stop the trigger of BEARER RESOURCE ALLOCATION REQUEST once it get rejected from network.

Answer 1

When UE is successfully attached to N/W with at least one default bearer and wants to establish a dedicated bearer, then UE sends the Bearer Resource Allocation Request to MME. The dedicated bearer could be used for VoLTE or YouTube streaming or any dedicated GBR use purpose.

Answer 2

As part of VoLTE call setup, receiver side of the call triggers bearer resource allocation request towards MME to get the resource allocated at network side to make successful VoLTE call.