Computer Networks

Compare the 10 best VPN services of 2026, then verify any tunnel with our free IP, VPN, and speed test tools before the money-back window closes.

WireGuard vs OpenVPN vs IKEv2 in 2026: configs, iperf3 benchmarks, DCO performance, and fixes for blocked ports, MTU stalls, and broken Windows VPN.

TCP and UDP explained: how the internet's two transport protocols differ in reliability, speed, and overhead, and when each one is the right choice.

A firewall filters network traffic against security rules. Learn how packet filtering, stateful inspection, and NGFWs work, with command examples.

Run a free blacklist IP address check across 80+ DNS blocklists in minutes. Learn how to check if your IP is blacklisted and get delisted fast.

A proxy server sits between your device and the internet. Learn how proxies work, their types, and how they differ from VPNs.

Port forwarding maps internet traffic from a public IP and port to a private device. Learn how it works, when to use it, and security trade-offs.

A router connects networks at Layer 3 using IP addresses. A switch connects devices within a LAN at Layer 2 using MAC addresses. Learn the key differences.

Learn what ICMP is, how it works, and why the Internet Control Message Protocol matters for network diagnostics and troubleshooting.

A subnet mask splits an IP address into network and host portions. Learn how it works, how to read one, and why it matters.

A MAC address is a unique hardware ID assigned to network interfaces. Learn how it works, how it differs from an IP address, and why randomization matters.

Ping is a network diagnostic utility that tests host reachability and measures latency using ICMP echo requests and replies.