What type of attack occurs when a router is flooded with many open connections so that all hosts behind it are effectively disabled?

• A. ARP redirect
• B. Physical attack
• C. Digital attack
• D. Denial of service

Answer: (D)

Denial of Service targets availability by overwhelming resources. Flooding a router with a large number of open connections uses up CPU, memory, and bandwidth, leaving legitimate traffic unable to pass and causing all hosts behind the router to be effectively disabled. This specific impact—making services unavailable through resource exhaustion—fits the DoS idea precisely. An ARP redirect focuses on manipulating traffic flow to intercept or alter packets, not on disabling access for a whole network. A physical attack involves tampering with hardware, not overwhelming a network service. A digital attack is a vague label and doesn’t describe the concrete outcome here.