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How Networks Fit Together From Router to Wireless Access
A plain-language tour of how routers, switches, firewalls and wireless access points connect in a small organization, and what each layer contributes.
Systems and Infrastructure
Network Infrastructure
The building blocks that move data between devices and sites.
A Beginner Guide to Subnets and Network Addressing
Learn how IP address ranges are divided into subnets, what a subnet mask and slash notation mean, and why organizations split their networks this way.
Bandwidth, Latency and Packet Loss Explained
Bandwidth, latency and packet loss each describe a different side of connection quality. Learn what they mean, how they interact and how to read them.
How Firewalls Filter Traffic
A firewall allows or blocks network traffic according to rules. See how rules are matched, what default deny means and what firewalls cannot do.
Routers, Switches and Access Points Compared
Routers, switches and access points look similar but do different jobs. Compare what each device does, where it sits and when you need one.
Troubleshooting a Slow Network Step by Step
A methodical way to find why a network feels slow: define the problem, test wired and wireless, check each layer and change one thing at a time.
Understanding Wi-Fi Standards, Channels and Interference
Why Wi-Fi speed and reliability vary: how standards, the 2.4, 5 and 6 GHz bands, channels, walls and neighboring networks all affect wireless performance.
What a VPN Does and What It Does Not
A VPN creates an encrypted tunnel between your device and another network. Learn what that protects, what it leaves exposed and how businesses use it.
What an IP Address Is and How DNS Finds It
An IP address identifies a device on a network, and DNS translates names into those addresses. Follow what happens when you type a web address.
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