Suggest an editImprove this articleRefine the answer for “What is network security?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**Network security** is a set of measures, technologies, and rules that protect computer networks and the data transmitted through them from unauthorized access, attacks, and failures. **Key point:** network security protects confidential data, keeps the network running reliably, and prevents financial and reputational losses.Shown above the full answer for quick recall.Answer (EN)Image**Network security** is a set of measures, technologies, and rules that **protect computer networks and the data** transmitted through them from unauthorized access, attacks, and failures. In simpler terms: *network security exists so attackers cannot get into the network, and data cannot be stolen, tampered with, or used to disrupt the system.* Why network security is needed Modern networks are constantly connected to the internet, which means: - they can be **hacked**, - data can be **intercepted**, - services can be **taken down** (for example, by DDoS attacks). Network security helps: - protect **confidential data** (passwords, personal information), - keep the **network running reliably**, - prevent **financial and reputational losses**. --- ## What network security actually protects ### 1. **Data** So that it is not: - stolen, - altered, - intercepted in transit. ### 2. **Devices** - servers, - computers, - routers, - network equipment. ### 3. **Users** So attackers cannot gain access under someone else's account. --- ## Main network threats This is often asked in interviews. - **Hacking** (unauthorized access) - **Malware** (viruses, trojans) - **Traffic interception** (sniffing) - **DDoS attacks** (overloading a service) - **Phishing** (deceiving users) --- ## Main network security tools ### Firewalls Filter incoming and outgoing traffic: decide what to let through and what not to. ### Encryption Makes data unreadable to outsiders (for example, HTTPS, VPN). ### Authentication and authorization Verify: - **who you are** (authentication), - **what you're allowed to do** (authorization). ### Intrusion detection systems Monitor suspicious activity on the network.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.