Compare
Side-by-side on the decisions that recur: TCP vs UDP, HTTP/2 vs HTTP/3, flow vs congestion control, L4 vs L7, forward vs reverse proxy, IPv4 vs IPv6 — with when to choose each.
TCP vs UDPHTTP/2 vs HTTP/3Flow control vs Congestion controlSwitch vs RouterForward proxy vs Reverse proxyL4 load balancing vs L7 load balancingServer-Sent Events vs WebSocketsIPv4 vs IPv6ARP (IPv4) vs Neighbor Discovery (IPv6)Keep-alive (reuse) vs New connection per request
TCP vs UDP
A reliable, ordered byte stream between two endpoints…
HTTP/2 vs HTTP/3
One TCP connection, TLS on top…
Flow control vs Congestion control
The receiver — its socket buffer must not overflow…
Switch vs Router
Destination MAC address (layer 2)…
Forward proxy vs Reverse proxy
Clients — it makes requests on their behalf…
L4 load balancing vs L7 load balancing
IP addresses and TCP/UDP ports…
Server-Sent Events vs WebSockets
Server → client only; client uses ordinary requests to talk …
IPv4 vs IPv6
32 bits, dotted decimal `203.0.113.7`…
ARP (IPv4) vs Neighbor Discovery (IPv6)
"Who has 192.168.1.1? Tell 192.168.1.42"…
Keep-alive (reuse) vs New connection per request
Just the request RTT after the first…