What is role of TMSI during SRVCC?

Mobility
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1

Hi Experts,
Please let me know what is role of TMSI during SRVCC?

2

During call Transfer, the MSC Server performs other TMSI reallocation towards the UE.
And it also performs a MAP Update Location to the HSS/HLR.
Now all steps are closed & Voice is flowing on new Path Similarly, for Data Part, Handover completion & Bearer Updation is done between SGSN & PGW. so that user can start Internet Session in 3G radio Now.