Computer Networking

Frames, addresses, routing, TCP, DNS, HTTP and TLS — explained with animations and commands you can run

Networking Crash Course

Fourteen sections with a mental model and an animation each: encapsulation, MAC addresses and switching, ARP, subnets and CIDR, routing and NAT, sockets and ports, the TCP handshake, retransmission, flow and congestion control, DNS, HTTP/1.1 through HTTP/3, TLS, load balancers and CDNs, and a debugging ladder.

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Networking Detailed Course

Thirty-eight sections from first principles: Ethernet framing, VLANs and spanning tree, IPv4 and IPv6, subnetting arithmetic, MTU and fragmentation, OSPF and BGP, NAT and DHCP, the socket API, TCP internals and tuning, DNS in depth, HTTP/2 and QUIC, TLS and the PKI, proxies, CDNs, cloud networking, security, and a performance-debugging playbook.

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