How it works
Devices on a LAN (local area network) reach each other directly through switches and Wi-Fi access points, and a router joins the LAN to other networks. The internet is a WAN (wide area network) on a global scale, and companies also build private WANs between offices with leased lines, SD-WAN services or site-to-site VPNs.
A subnet is a block of addresses written in CIDR notation: 192.168.1.0/24 fixes the first 24 bits, which leaves 256 addresses, 254 of them usable by devices. Subnets and VLANs (virtual LANs that share the same switches) keep groups of devices apart. Offices often give guests, printers and cameras their own VLANs, so a problem on one cannot spread to the rest of the network.
Related terms
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