Which two items best describe a Cisco IOS IP SLA responder? (Choose two.)

A.
required at the destination to implement Cisco IOS IP SLA services

B.
improves measurement accuracy

C.
required for VoIP jitter measurements

D.
provides security on Cisco IOS IP SLA messages via LEAP or EAP-FAST authentication

E.
responds to one Cisco IOS IP SLA operation per port

F.
stores the resulting test statistics