Suggest an editImprove this articleRefine the answer for “What does a router do?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**A router** is a network device that forwards IP packets between different networks and chooses the path those packets will take next. **Key point:** a router analyzes only the IP header of a packet (not application data), uses a routing table to choose the next hop, and does not forward broadcast traffic between networks.Shown above the full answer for quick recall.Answer (EN)Image**A router** is a network device that **forwards IP packets between different networks** and **chooses the path those packets will take next**. Short and clear: **a router connects different networks and decides where to send a packet next**. --- ## Main tasks of a router ### 1. **Connects different networks** A router works when: - devices are located **in different subnets** - data needs to be passed **beyond the local network** Without a router, communication between subnets is impossible. --- ### 2. **Analyzes the destination IP address** A router: - looks at the **destination IP address** in the packet - determines **which network the recipient belongs to** It does not analyze application data, only the IP header. --- ### 3. **Chooses a route** Using the **routing table**, a router determines: - through which interface to send the packet - to which next hop If there are several routes, **the most suitable one** is chosen. --- ### 4. **Forwards the packet further** After choosing a route, a router: - decreases the TTL value - wraps the IP packet in a **new data link layer frame** - sends it to the next network This process repeats at every router along the path. --- ### 5. **Separates broadcast domains** A router: - **does not pass broadcast traffic** - limits it to the boundaries of a single subnet This improves the network's stability and scalability. --- ## What a router does NOT do Important for an interview A router: - does not forward frames by MAC addresses (that is L2) - does not guarantee packet delivery - does not manage TCP connections - does not analyze application data --- ## At what layer a router operates - main layer: **the network layer (L3)** - works with: - IP addresses - packets - routesFor the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.