Copyright Goodheart-Willcox Co., Inc. Chapter 8 Overview of Network Security and Network Threats 283 6. Which is true about a denial of service (DoS) attack? A. Data can be stolen in transit. B. You can prevent this by blocking port 23. C. Its objective is to prevent legitimate access to network services. D. Encryption of data is necessary to prevent data loss. 7. A Smurf attack is done by: A. conducting a ping sweep. B. fl ooding the victim with ICMP requests. C. failing to close the three-way handshake connection. D. sending malformed packets to the victim. 8. Which defense would help against a SYN fl ood? A. Run netstat –a. B. Block ICMP at the fi rewall. C. Prevent incoming packets at the fi rewall. D. Implement a fl ood guard. 9. Why would a hacker conduct a ping sweep? A. To fi nd open ports on the network. B. To view data in transit. C. To identify known hosts on the network. D. To conduct a denial of service attack. 10. What should an administrator use to remote into another host such as a router? A. SCP B. SSH C. Telnet D. Netstat Application and Extension of Knowledge 1. Take a closer look at IANA. Discover its responsibilities and role in IP addresses and domain names. Create a presentation outlining what additional information you learn about IANA. Be prepared to deliver your presentation to the class. 2. Consider this scenario: your organization needs to subnet its existing Class C private network (192.168.100.0) into three networks. Identify the three networks you would create and their corresponding subnet masks in both decimal and CIDR format. 3. On your own home network or the home network of a friend or relative, run a ping sweep. Do you recognize all devices found? Prepare a report describing your results. Include a summary. 4. Using the website whois.domaintools.com, look up Verizon.com. Review the information provided by this site. What IP address was it assigned? Locate the hosting history. Perform the same tasks on your school system’s website. Summarize the data in a one-page report that you believe is useful if you suspect an IP address is part of a cyberattack. 5. Prepare for a roundtable discussion with your classmates on the threats of DoS attacks. Consider measures that can be taken to identify an attack in progress. Also consider preventative measures that can be taken. Participate in the class roundtable discussion.