C-46

Phone to SIP Phone via Gateway: Call Screening
Figure C-17. Call Flow Diagram: Call Screening
SIP Phone UA Marshal
1. INVITE
2. 100
Redirect Server
3. INVITE
4. 302
5. ACK
Feature Server:
Call Screening
6. INVITE
7. 100
8. INVITE
9. 302
10. ACK
11. 403
12. ACK
13. 403
14. ACK