A denial of service (DoS) or distributed denial of service (DDoS) is an attempt to make a computer ability unavailable to users trying to access it. These most commonly occur when a person decides to disrupt an internet site or service from working correctly. High-profile web servers such as banks and credit card gateways are most at risk.

DoS attacks are achieved by targeting the intended computers resorces, so it can not carry out it’s intended tasks and forcing it to reset and obstructing the communication between the target and the intended user.

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