What you will learn
- The order of a home network: provider line → modem (or fiber ONT) → router → switch → access point.
- The one job of each box, and why a switch or an access point can’t take the router’s place.
- Why private addresses like 192.168.1.37 come from the router, not from your provider.
- What is inside a Wi-Fi router and a provider gateway, and how to avoid double NAT.
Key terms
Modem turns the provider’s signal into Ethernet: a cable modem (DOCSIS) on coax, an ONT on fiber, a DSL modem on a phone line.
Router connects your home network to the internet. It shares one public address with every device (NAT), hands out private addresses (DHCP) and blocks unwanted traffic from outside.
Switch adds wired ports to the same network and sends traffic only to the port where the destination device is connected.
Access point turns a wired connection into Wi-Fi (IEEE 802.11) and bridges wireless devices onto the same network.
A Wi-Fi router combines a router, a small switch and an access point. A gateway from your provider usually adds a modem to all of that.
Sources
- Cable modem (Wikipedia)
- Optical network terminal (Wikipedia)
- Router (Wikipedia)
- Network switch (Wikipedia)
- Wireless access point (Wikipedia)
- Residential gateway (Wikipedia)
- RFC 1918: Address Allocation for Private Internets
- RFC 3022: Traditional IP Network Address Translator (NAT)
- What is a switch vs a router? (Cisco)