Protection and prevention
No single security tool is enough. The idea is to build layers of protection (defence in depth), like a castle: walls, a moat, guards and a vault. If one layer falls, the next stops the attacker.
| Multi-factor authentication (MFA) | Something you know (a password) + something you have (your phone) or something you are (a fingerprint). Even a stolen password isn't enough. One of the strongest, cheapest protections. |
| Least privilege | Each employee gets only the access their job needs. A warehouse clerk doesn't need to see payroll. |
| Patching | Most attacks exploit known flaws that already have fixes. Update systems regularly. |
| Encryption | For data in transit (HTTPS, VPN) and at rest (disk and database encryption). |
| 3-2-1 backups | 3 copies of the data, on 2 different storage types, with 1 copy off-site or offline. This is what saves you from ransomware. |
Controls are grouped by when they act: preventive ones stop an incident (firewall, MFA), detective ones spot it (logs, intrusion detection systems, cameras), and corrective ones restore things (recovering from backups).
Zero Trust is the modern approach: “never trust, always verify”. We don't assume a device is safe just because it's inside the network; every request checks the user's identity and the device's health before access is granted.
And passwords? Length matters more than complexity. Try the tool (nothing you type is sent anywhere, and it's best to test examples rather than your real password):
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A rough teaching estimate. Even more important: a different password per account, a password manager, and MFA.