What happens if RLF happen on serving cell during ongoing VoLTE call re-establishment?

4G LTE
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Hello Experts.

If during ongoing VoLTE call re-establishment occur on serving cell due to RLF…

Then what will be next step?

Will call drop here during re-establishment or mute call?

2

Call will not drop if S1 bearer is preserved at core side.

After RRE success call will resume but muting may observed.

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If a VoLTE call is ongoing and a RRC connection re-establishment occurs on the serving cell due to RLF, the call will be muted during the re-establishment process. The call will not drop unless the re-establishment fails.

The re-establishment process will typically take a few seconds. During this time, the UE will send a RRC Connection Reestablishment Request message to the serving cell. The serving cell will then verify the UE’s identity and context, and if everything is correct, it will send a RRC Connection Reestablishment Response message. Once the UE has received the RRC Connection Reestablishment Response message, the call will be unmuted and will continue as normal.

If the re-establishment fails, the UE will enter a RRC Idle state and the call will be dropped.

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