A malicious system continuously sends an extremely large number of SYN packets to a server.
Which of the following BEST describes the resulting effect?
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A. B. C. D.D.
The given scenario describes a type of denial-of-service (DoS) attack known as a SYN flood attack. In a typical TCP connection establishment process, a client sends a SYN packet to the server, and the server responds with a SYN-ACK packet, which the client acknowledges with an ACK packet to complete the connection setup. In a SYN flood attack, the attacker sends a large number of SYN packets to the server, but does not respond to the SYN-ACK packets sent by the server. As a result, the server's resources are tied up in maintaining half-open connections, and legitimate clients are unable to connect to the server.
Option A: The server may indeed become unable to serve clients due to lack of available bandwidth, but this is not the primary effect of a SYN flood attack.
Option B: The server's firewall may become overwhelmed by the amount of data transmitted, but this is not the primary effect of a SYN flood attack.
Option C: The server may experience problems with reassembling fragmented packets, but this is not the primary effect of a SYN flood attack. SYN flood attacks do not typically involve fragmented packets.
Option D: This is the correct answer. The server may exhaust its memory resources maintaining half-open connections, which can lead to a denial-of-service condition. As a result, legitimate clients may be unable to connect to the server or experience significant delays.
To mitigate the effects of a SYN flood attack, various countermeasures can be implemented, such as limiting the number of half-open connections allowed, implementing firewalls and intrusion prevention systems (IPS), or using specialized network devices designed to detect and prevent such attacks.