A Denial of Service (DoS) attack is characterized by the act of overwhelming a network or service, rendering it unavailable to legitimate users. This is achieved by flooding the target with excessive traffic or requests, which exhausts its resources and prevents it from functioning properly. Consequently, users are unable to access the service, disrupting normal operations and potentially causing significant downtime and financial loss.
The primary goal of a DoS attack is to deny access to the target rather than to cause damage to the data itself or to steal information. This distinguishes it from other types of cyber threats, such as attacks that aim to encrypt data, steal credentials, or modify files. In contrast to those scenarios, which focus on data theft or integrity, the intent behind a DoS attack is purely to obstruct access to services.