A network administrator is concerned that the network is vulnerable to a denial-of-service attack. What steps should be taken to reduce this threat? (Select all that apply.)

A) Prevent intrusions.
B) Configure the router to block directed broadcasts to the network.
C) Set up a spoofing account so that the attacker doesn't know which machine to attack.
D) Use access lists to allow only sources from the network to enter the router's interfaces.
E) There isn't a way to reduce this threat.

A, B, D