哪位高手能提供下一次完整的呼叫、切换的后台信令流程，谢谢！

呼叫流程
Channel request
immediate assignment
Cm service request
Cm service accept
Setup
Call proceeding                    
Assignment command
Assignment complete
Alerting
Connect
Connect acknowedge
Disconnect
Release
Release complete
Channel release
切换流程：
Handover  command
Handover  access
Handover  complete(失败则Handover  failure）