Packet sniffers and port analyzers can be used as legitimate troubleshooting tools, but can also be used by potential attackers. The ICMP protocol is also useful for diagnosing problems, and several diagnostic tools, such as ping, use ICMP. However, ping can be used to launch a denial-of-service attack.

1. Discuss the impact of the dual nature of packet sniffers and port analyzers on network maintenance and security.

2. Give an example of how you would use each tool for legitimate troubleshooting.

3. Discuss the pros and cons of configuring a packet-filtering firewall to drop ICMP packets.