#networking

13 articles

VPNs and Tunneling

A VPN builds an encrypted tunnel across the public internet by wrapping one network's packets inside another's — encapsulation — so a remote device can reach a private network as if plugged into the office wall.

10 min read·Jul 30, 2026

Networks & the Internet

BGP: How the Internet's Networks Agree on Routes

The internet is a mesh of ~75,000 independently run networks. BGP is how they advertise reachable prefixes to each other and negotiate routes — driven by business policy, not shortest path, and held together by trust.

10 min read·Jul 26, 2026

Networks & the Internet

Wi-Fi: Networking Through the Air

How Wi-Fi carries a link-layer over a shared radio medium, why it must avoid collisions instead of detecting them, and why the rated speed on the box is a ceiling everyone shares, not a promise to each device.

10 min read·Jul 24, 2026

Networks & the Internet

Peer-to-Peer: The Internet Without a Center

In a peer-to-peer network there is no central server — every node is both client and server. BitTorrent splits a file into pieces and a swarm trades them, so the more people want a file, the faster everyone gets it.

10 min read·Jul 23, 2026

Networks & the Internet

Ethernet: How Machines Share a Wire

The layer beneath IP: how a packet physically crosses a local network, why every device has a 48-bit MAC address, how a switch learns where each machine lives, and how ARP turns an IP into the MAC needed to actually deliver a frame.

10 min read·Jul 22, 2026

Networks & the Internet

Firewalls: Filtering the Traffic

A firewall decides which traffic may pass by matching packets against rules on address, port, and protocol. The real leap is memory: a stateful firewall welcomes the replies to connections you started while turning away strangers who arrive uninvited.

9 min read·Jul 21, 2026

Networks & the Internet

CDNs: Bringing the Web Closer

A load balancer scales a site in one place, but distance sets a floor on latency that no amount of hardware can beat. CDNs scale geographically — caching content at hundreds of edge locations near users, and steering each request to the closest one.

10 min read·Jul 20, 2026

Networks & the Internet

Ping and Traceroute: Seeing the Network

Ping times an echo to tell you a host is alive and how far away it feels; traceroute lists every router in between by deliberately expiring packets one hop farther each time. Both ride on ICMP.

9 min read·Jul 19, 2026

Networks & the Internet

Certificates and the Chain of Trust

TLS hands your browser a public key and says 'encrypt to me' — but anyone can generate a key. Certificates and a chain of signatures reaching back to a short list of preinstalled authorities are what tie that key to a real identity.

10 min read·Jul 16, 2026

Networks & the Internet

DHCP: How Your Device Joins a Network

How a device with no address at all joins a network: the DORA handshake that leases it an IP address, subnet mask, default gateway, and DNS server automatically — on a lease that quietly expires.

9 min read·Jul 15, 2026

Networks & the Internet

NAT: How Billions Share Four Billion Addresses

There are about four billion possible IPv4 addresses and far more than four billion connected devices — yet everything works. Network Address Translation is the stopgap hiding in every home router that lets a whole network share a single public address, disambiguated by port.

9 min read·Jul 12, 2026

Networks & the Internet

DNS: The Internet's Phone Book

Humans use names; the network routes to numbers. DNS bridges the gap with a distributed, delegated tree — no single machine holds the whole thing, and caching makes it feel instant.

10 min read·Jul 8, 2026

Networks & the Internet

IP Addresses and Routing

IP gives every device an address and lets routers forward packets hop by hop toward it — best-effort, connectionless, and with no single router that knows the whole route.

10 min read·Jul 4, 2026