A Pulse Wave attack is a type of DDoS attack that uses a botnet to send high-volume traffic pulses at regular intervals, typically lasting for a few minutes each. The attacker can adjust the frequency and duration of the pulses to maximize the impact and evade detection. A Pulse Wave attack can exhaust the network resources of the target, as well as the resources of any DDoS mitigation service that the target may use. A Pulse Wave attack can also conceal the attacker's identity, as the traffic originates from multiple sources that are part of the botnet. A Pulse Wave attack can bypass simple defensive measures, such as IP-based blocking, as the traffic can appear legitimate and vary in source IP addresses.

The other options are less effective or feasible for the attacker's objectives. A protocol-based SYN flood attack is a type of DDoS attack that exploits the TCP handshake process by sending a large number of SYN requests to the target server, without completing the connection. This consumes the connection state tables on the server, preventing it from accepting new connections. However, a SYN flood attack can be easily detected and mitigated by using SYN cookies or firewalls. A SYN flood attack can also expose the attacker's identity, as the source IP addresses of the SYN requests can be traced back to the attacker. An ICMP flood attack is a type of DDoS attack that sends a large number of ICMP packets, such as ping requests, to the target server, overwhelming its ICMP processing capacity. However, an ICMP flood attack from a single IP can be easily blocked by using IP-based filtering or disabling ICMP responses. An ICMP flood attack can also reveal the attacker's identity, as the source IP address of the ICMP packets can be identified. A volumetric flood attack is a type of DDoS attack that sends a large amount of traffic to the target server, saturating its network bandwidth and preventing legitimate users from accessing it. However, a volumetric flood attack using a single compromised machine may not be sufficient to overwhelm the network bandwidth of a major online retailer, as the attacker's machine may have limited bandwidth itself. A volumetric flood attack can also be detected and mitigated by using traffic shaping or rate limiting techniques.Reference:

Pulse Wave DDoS Attacks: What You Need to Know

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