Tag
#internet
11 articles
HTTP/2 and HTTP/3: Reinventing the Web's Transport
The verbs and headers of HTTP are the same as 1997, but the transport under them was re-engineered twice. HTTP/2 multiplexes many streams over one TCP connection; HTTP/3 throws out TCP entirely for QUIC over UDP to escape head-of-line blocking.
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.
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.
Email: The Internet's Oldest Application
Email is a distinct application on the internet's plumbing, older than the web. It relays store-and-forward from mail server to mail server via a DNS MX lookup, and by original design never checked who the sender claimed to be — which is why SPF, DKIM, and DMARC exist.
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.
TLS: Encrypting the Web
Plaintext HTTP let anyone on the path read your passwords. TLS wraps the connection in encryption by using slow asymmetric crypto only to authenticate the server and agree a key, then switching to fast symmetric crypto for the data.
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.
HTTP and the World Wide Web
The web is one application running on top of the internet's plumbing. HTTP is how a browser asks a server for a resource — a stateless request and response that cookies and the Host header quietly extend into logins and shared hosting.
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.
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.
Packet Switching
Why the internet chops your data into hundreds of independently-routed packets instead of reserving a wire for you, and how that one choice buys both efficiency and resilience.