Which of the features below does a B2BUA deliver to a SIP-based VoIP architecture? (Choose 3 answers)

Which of the features below does a B2BUA deliver to a SIP-based VoIP architecture? (Choose 3 answers)
A . centralized call management
B . SIP-based VoIP interworking between LAN and WAN
C . management and monitoring of the entire call state
D . Provide conversion of TDM to DIP
E . connect legacy phones

Answer: A,B,C

Explanation:

Reference: http://www.eetimes.com/document.asp?doc_id=1203045