Which type of attack is specifically designed to flood a network with excessive requests?

A Denial of Service (DoS) attack is specifically designed to overwhelm a network or service with excessive requests, rendering it unavailable to legitimate users. This type of attack typically exploits the capacity limitations of network resources by flooding them with a high volume of requests, ultimately leading to slowdowns or complete interruptions of service. The goal is to disrupt the normal functioning of a targeted system, rather than to gain unauthorized access to data or credentials.

In contrast, phishing is focused on deceiving users into providing sensitive information, such as passwords or credit card numbers, typically through fraudulent messages. A man-in-the-middle attack involves intercepting and potentially altering communications between two parties without their knowledge, which is unrelated to flooding a network with requests. SQL injection targets databases by inserting malicious SQL queries into input fields, aiming to manipulate or extract data, rather than overwhelming a network traffic. Therefore, the characteristics and intended impact of a DoS attack uniquely define it as the choice that matches the requirement of flooding a network with excessive requests.