Botnet

A botnet is a number of Internet-connected devices used by a botnet owner to perform various tasks. Botnets can be used to perform Distributed Denial Of Service Attack, steal data, send spam, allow the attacker access to the device and its connection. The owner can control the botnet using command and control (C&C) software. The word botnet is a combination of the words robot and network. The term is usually used with a negative or malicious connotation.

Most of the time when botnets are in the legal area are commonly used for Distributed computing which is a field of computer science that studies distributed systems. A distributed system is a software system in which components located on networked computers communicate and coordinate their actions by passing messages. The components interact with each other in order to achieve a common goal. Three significant characteristics of distributed systems are: concurrency of components, lack of a global clock, and independent failure of components. A command and control may be present in the distributed computing but no zombie computer is present in this type of system.

Botnets sometimes compromise computers whose security defenses have been breached and control ceded to a third party. Each such compromised device, known as a "bot", is created when a computer is penetrated by software from a malware (malicious software) distribution. The controller of a botnet is able to direct the activities of these compromised computers through communication channels formed by standards-based such as IRC and (HTTP).

Botnets are increasingly rented out by cyber criminals as commodities for a variety of purposes.

Botnet architecture has evolved over time in an effort to evade detection and disruption. Traditionally, bot programs are constructed as clients which communicate via existing servers. This allows the bot herder (the person controlling the botnet) to perform all control from a remote location, which obfuscates their traffic. Many recent botnets now rely on existing peer-to-peer networks to communicate. These P2P bot programs perform the same actions as the client-server model, but they do not require a central server to communicate.

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