Which two options in VCS-C and VCS-E handle presence status for registered endpoints? (Choose two.)
A. back to back user agent
B. presence user agent
C. domain name system
D. presence server
E. presence proxy
Which two options in VCS-C and VCS-E handle presence status for registered endpoints? (Choose two.)
A. back to back user agent
B. presence user agent
C. domain name system
D. presence server
E. presence proxy