COMPUTER NETWORKING

Detailed explanation-1: -Email spam– though email is seen today as an older vector for attack, spam botnets are some of the largest in size. They are primarily used for sending out spam messages, often including malware, in towering numbers from each bot. The Cutwail botnet for example, can send up to 74 billion messages per day.

Detailed explanation-2: -A botnet [short for bot network] is a network of hijacked computers and devices infected with bot malware and remotely controlled by a hacker. The bot network is used to send spam and launch Distributed Denial of Service [DDoS] attacks, and may be rented out to other cybercriminals.

Detailed explanation-3: -Explanation: Botnets are implemented to carry out distributed DDoS attacks, steal data, send spam messages & permits the hacker to access various devices & its connection. Explanation: Botnets usually are not used for encrypting files for ransom.