Field Notes / Networking

Observing the network

Notes about internet connectivity, latency, transport protocols, routing and repeatable measurements.

Methodology

Measure, don't assume

Throughput varies with route, protocol, packet loss and measurement method. Compare results across several independent destinations and both traffic directions.

Keep track of sample size, test duration and the difference between an advertised port rate and end-to-end application throughput.

Practical observations

TCP retransmissions, UDP loss, round-trip time and congestion control all affect real-world performance. Small transfers alone seldom describe the full picture.