Kali Linux Hacking Lab for Beginners

A virtual private network carries traffic through an encrypted tunnel over a public network so that a remote device or site behaves as though it were connected to a private one.

An intrusion detection system watches network traffic or host activity for signs of attack and raises alerts, while an intrusion prevention system sits inline and can block what it recognises.

A SIEM collects logs and events from across an organisation's systems into one searchable store, correlates them into alerts, and retains them for investigation and compliance.

A wireless LAN connects devices to a network over radio using the 802.11 family of standards, through access points that bridge the wireless medium onto the wired network and enforce the authentication and encryption that the shared airwaves demand.

TCP/IP is the family of protocols on which the internet runs: IP moves packets between addresses without guarantees, and TCP or UDP ride on top to deliver either a reliable ordered stream or fast unordered messages.

The OSI model is a seven-layer reference framework that separates networking into physical transmission, link, network, transport, session, presentation and application concerns, used to reason about where a problem sits rather than to describe any real protocol stack.

A dedicated server is an entire physical computer rented by a single customer, with no hypervisor taking a share and no other tenants on the hardware, chosen when consistent performance, specific components or provable isolation matter more than the ability to resize in seconds.

Managed hosting is any plan where the provider runs the server on your behalf, covering updates, hardening, monitoring, backups and tuning, so the thing being sold is administration time with a machine attached rather than the machine itself.

Cloud hosting is the model in which servers, storage and databases are created on demand through an API from a provider's pooled hardware and billed for the time they exist, rather than rented as a fixed box by the month.