Networking resources

Glossary

Bandwidth

The maximum amount of data a link can carry per second, measured in Mbps or Gbps.

Throughput

The data rate actually achieved, always lower than bandwidth because of overhead and congestion.

Latency

The delay between sending data and it arriving, usually reported as round-trip time in milliseconds.

Ping

A utility that measures round-trip time by sending echo requests to a host.

Jitter

The variation in latency between consecutive packets; high jitter breaks calls and games.

Packet loss

The share of packets that never reach their destination and must be retransmitted.

Buffer bloat

Excessive queueing in network equipment that inflates latency whenever the link is busy.

DNS

The Domain Name System, which resolves hostnames into IP addresses.

DHCP

The protocol that automatically assigns IP addresses and network settings to devices.

NAT

Network Address Translation, which lets many private addresses share one public address.

CGNAT

Carrier-grade NAT, where the ISP shares one public address across many subscribers.

MTU

The largest packet size a link accepts, typically 1500 bytes on Ethernet.

QoS

Quality of Service — prioritising certain traffic classes when a link is saturated.

Mesh network

Multiple access points cooperating to cover a large area with one WiFi name.

Backhaul

The link between mesh nodes, either wireless or wired, that carries aggregated traffic.

Traceroute

A diagnostic that lists each router hop between you and a destination.

TTL

Time To Live — a hop counter in IP, and a cache lifetime in DNS.

Symmetric connection

A link with equal upload and download capacity, typical of fiber.