What are the common countermeasures against ping sweep attacks in network security?
a. Common countermeasures against ping sweep attacks include disabling firewalls to allow ICMP echo requests.
b. Common countermeasures against ping sweep attacks include configuring firewalls to block ICMP echo requests, limiting the rate of ICMP traffic, using intrusion detection systems to recognize and alert on large-scale ICMP requests, and regularly monitoring and auditing network logs for any unusual activity.
c. Common countermeasures against ping sweep attacks include removing antivirus software from all network devices.
d. Common countermeasures against ping sweep attacks include ignoring ICMP traffic altogether.