WiFi glossary

Basics

Router: The box that creates your home network and shares one internet connection with all your devices. Most also broadcast WiFi.
Modem: The box that connects your home to your internet provider’s line (cable, DSL, or fiber). A router plugs into it.
Gateway: A modem and router in one box, often rented from your internet provider.
Access point: A device that adds WiFi coverage to a wired network. Mesh nodes are a type of access point.
SSID: Your WiFi network’s name.
Ethernet: A wired network connection. It is faster and more stable than WiFi for devices that stay put, like TVs, consoles, and desktops.

WiFi 6 (802.11ax): The WiFi standard that improved performance on busy networks with many devices. Works on 2.4 GHz and 5 GHz.
WiFi 6E: WiFi 6 extended to the 6 GHz band, which has more room and less interference.
WiFi 7 (802.11be): The newest standard. It adds wider 320 MHz channels on 6 GHz and Multi-Link Operation (MLO), which lets a device use more than one band at once. You need WiFi 7 devices to get the full benefit.
2.4 GHz: The band with the longest range but the lowest speeds and the most interference. Many smart-home devices only use 2.4 GHz.
5 GHz: Faster than 2.4 GHz with shorter range. The workhorse band for most phones and laptops.
6 GHz: The newest band, used by WiFi 6E and WiFi 7. It’s fast and uncrowded, but it has the shortest range and struggles with walls.
Channel width: How much of a band a connection uses, measured in MHz. Wider channels are faster but more prone to interference.
DFS channels: Some 5 GHz channels are shared with weather and aircraft radar. Routers must move off them if radar is detected, which can cause brief drops.
Band steering: A router feature that moves devices to the best band automatically.
MU-MIMO and OFDMA: Features that let a router talk to several devices at the same time instead of taking turns. They help most in busy homes.
Beamforming: A technique that focuses the WiFi signal toward a device instead of spreading it evenly.

Mbps and Gbps: Megabits and gigabits per second, the unit for internet and WiFi speed. 1 Gbps is 1,000 Mbps. Downloads in your browser often show MB/s (megabytes); divide Mbps by 8 to compare.
Download and upload: Download is data coming to you (streaming, browsing). Upload is data you send (video calls, cloud backups, posting videos).
Latency (ping): How long data takes to make a round trip, in milliseconds (ms). Lower is better, especially for gaming and calls.
Jitter: How much latency varies from moment to moment. High jitter makes calls choppy.
Bufferbloat: Lag caused when a busy connection makes data wait in a long queue. See our bufferbloat guide.
QoS and SQM: Quality of Service settings prioritize some traffic. Smart queue management (SQM) keeps latency low for everything when the connection is busy.
Signal strength (dBm, RSSI): How strong the WiFi signal is at a device. Numbers closer to zero are stronger: -50 dBm is excellent, -80 dBm is weak.
Dead zone: A spot in your home where WiFi is too weak to use.
Speed test: A tool that measures your download, upload, and latency. Test with a wired laptop first to separate internet problems from WiFi problems.

ISP: Internet service provider, such as Xfinity, Spectrum, AT&T, Verizon, T-Mobile, or Google Fiber.
Fiber: Internet delivered over fiber-optic lines. Usually the fastest and most consistent, with uploads as fast as downloads.
Cable: Internet delivered over the same coax lines as cable TV. Fast downloads, slower uploads, and shared with your neighborhood.
5G home internet (fixed wireless): Internet delivered over a cellular network to a gateway in your home.
ONT: The optical network terminal: the small box that converts a fiber line into an Ethernet connection for your router.
Data cap: A monthly limit on how much data you can use before extra charges or slower speeds.
Broadband label: A standardized label, required by the FCC, that shows a plan’s monthly price, fees, and typical speeds.
CGNAT: When your provider shares one public IP address among many customers. It can interfere with hosting game servers or remote access.

Mesh WiFi: A system of two or more units (nodes) that work together to cover a whole home under one network name.
Node or satellite: A unit in a mesh system that isn’t connected directly to the modem.
Backhaul: The connection between mesh nodes. It can be wireless or wired (Ethernet). Wired backhaul is faster and more reliable.
Tri-band: A router or mesh node with three radios, often used to give mesh backhaul its own band.
Extender (repeater): A device that picks up your WiFi and rebroadcasts it. Simpler and cheaper than mesh, but usually slower.
MoCA: A way to run an Ethernet connection over the coax cable already in many US homes.
Multi-gig (2.5GbE, 10GbE): Ethernet ports faster than 1 Gbps. Useful if your internet plan is faster than 1 Gbps or you use wired mesh backhaul.
Cat5e, Cat6: Ethernet cable types. Cat5e handles 1 Gbps and, at typical home lengths, 2.5 Gbps; Cat6 or better is a safer choice for 10 Gbps runs.

WPA3: The newest WiFi security standard. Use it if all your devices support it, or WPA2/WPA3 mixed mode if some don’t.
WPA2-AES: The older but still acceptable security setting. Avoid WEP, WPA, and TKIP.
WPS: A push-button or PIN setup feature. Convenient, but a known weak spot. Turn it off.
Guest network: A separate network for visitors and smart-home devices that keeps them away from your computers and phones.
Firmware: The software that runs your router. Keep it updated. See our router hardening checklist.
UPnP: A feature that lets devices open ports on your router automatically. Handy for some games and risky if you don’t need it.
Port forwarding: Manually letting outside traffic reach a device on your network, such as a game server or camera.
DNS: The internet’s address book: it turns website names into addresses. Some DNS services can block malicious sites.
VPN: A service that encrypts traffic between your device and the VPN provider. Useful on public WiFi; it doesn’t secure your router.

Matter: A smart-home standard that lets devices work with Apple Home, Google Home, Amazon Alexa, and SmartThings. See our Matter and Thread guide.
Thread: A low-power wireless network for smart-home devices like sensors and locks.
Thread border router: A device, often a smart speaker or streaming box, that connects a Thread network to your home network.
IoT: Internet of Things: smart plugs, cameras, thermostats, and other connected gadgets.