Which two considerations about secure network management are important? (Choose two.)

A.
log tampering

B.
encryption algorithm strength

C.
accurate time stamping

D.
off-site storage

E.
Use RADIUS for router commands authorization.

F.
Do not use a loopback interface for device management access.

Explanation:
http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/best/practices/recommend
ations.html
Enable Timestamped Messages
Enable timestamps on log messages:
Router(config)# service timestamps log datetime localtime show-timezone msec
Enable timestamps on system debug messages:
Router(config)# service timestamps debug datetime localtime show-timezone msec