A distributed port scan operates by A Blocking access to the scanning clients

A distributed port scan operates by a blocking access

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QUESTION 55A distributed port scan operates by: A. Blocking access to the scanning clients by the targeted hostB. Using denial-of-service software against a range of TCP portsC. Blocking access to the targeted host by each of the distributed scanning clientsD. Having multiple computers each scan a small number of ports, then correlating the resultsCorrect Answer: Section: (none)ExplanationExplanation/Reference:Explanation:Think of dDoS (distributed Denial of Service) where you use a large number of computers to createsimultaneous traffic against a victim in order to shut them down. D QUESTION 56You want to know whether a packet filter is in front of 192.168.1.10. Pings to 192.168.1.10 don't get answered.A basic nmap scan of 192.168.1.10 seems to hang without returning any information. What should you donext?
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C Section: (none) Explanation Explanation/Reference: QUESTION 57What does ICMP (type 11, code 0) denote? B QUESTION 58An nmap command that includes the host specification of 202.176.56-57.* will scan _______ number of hosts. C QUESTION 59A specific site received 91 ICMP_ECHO packets within 90 minutes from 47 different sites. 77 of theICMP_ECHO packets had an ICMP ID:39612 and Seq:57072. 13 of the ICMP_ECHO packets had an ICMPID:0 and Seq:0. What can you infer from this information? A. The packets were sent by a worm spoofing the IP addresses of 47 infected sitesB. ICMP ID and Seq numbers were most likely set by a tool and not by the operating systemC. All 77 packets came from the same LAN segment and hence had the same ICMP ID and Seq numberD. 13 packets were from an external network and probably behind a NAT, as they had an ICMP ID 0 and Correct Answer: Section: (none) Seq 0 B Explanation Explanation/Reference:
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