概要
- LTE网络Initial Attach
- IMS Client 注册
- VoLTE Call 的建立
- VoLTE Call 的释放
- IMS Client 去注册
VoLTE Protocol Stack
域的选择(Domain Selection)
- UE Capability - CS voice or PS voice
- Home Operator perference - SMS over IMS or SGs
- User settings - Voice-centric or Data centric
- Visited operator preference / visited network capability