What is BOT network???

A botnet is a collection of internet-connected devices, which may include PCs, servers, mobile devices and internet of things devices that are infected and controlled by a common type of malware. Users are often unaware of a botnet infecting their system.
Infected devices are controlled remotely by threat actors, often cybercriminals, and are used for specific functions, so the malicious operations stay hidden to the user. Botnets are commonly used to send email spam, engage in click fraud campaigns and generate malicious traffic for distributed denial-of-service attacks.

How botnets work

The term botnet is derived from the words robot and network. A bot in this case is a device infected by malware, which then becomes part of a network, or net, of infected devices controlled by a single attacker or attack group.

The botnet malware typically looks for vulnerable devices across the internet, rather than targeting specific individuals, companies or industries. The objective for creating a botnet is to infect as many connected devices as possible, and to use the computing power and resources of those devices for automated tasks that generally remain hidden to the users of the devices.

For example, an ad fraud botnet that infects a user's PC will take over the system's web browsers to divert fraudulent traffic to certain online advertisements. However, to stay concealed, the botnet won't take complete control of the web browsers, which would alert the user. Instead, the botnet may use a small portion of the browser's processes, often running in the background, to send a barely noticeable amount of traffic from the infected device to the targeted ads.

On its own, that fraction of bandwidth taken from an individual device won't offer much to the cybercriminals running the ad fraud campaign. However, a botnet that combines millions of devices will be able to generate a massive amount of fake traffic for ad fraud, while also avoiding detection by the individuals using the devices.

Botnet architecture

Botnet infections are usually spread through malware, such as a Trojan horse. Botnet malware is typically designed to automatically scan systems and devices for common vulnerabilities that haven't been patched, in hopes of infecting as many devices as possible. Botnet malware may also scan for ineffective or outdated security products, such as firewalls or antivirus software.