What are three functions of the NTP protocol? (Choose three.) Select exactly 3 answer(s) from the following:
A.
to connect to a reference source on the Internet
B.
to convert internal IP addresses to external IP addresses
C.
to install as an Intranet-based application
D.
to ensure that all network devices share a common time reference
E.
to provide routing functions at an ISR
F.
to aid in the collection of call detail records for billing