A、end-to-end network delay times that exceed 50 ms for real-time traffic are considered unacceptable

B、end-to-end network delay times that exceed 250 ms for real-time traffic are considered unacceptable

C、end-to-end network delay is not a factor as long as the  delay is consistent

D、some packet loss can be corrected by codec algorithms

E、RSVP handles voice packet retransmission

F、fragmentation is a result of packet loss