Essay catalogs common programmer misconceptions about LANs, from reliability and addressing to trust, latency, and topology assumptions

The article is a “falsehoods programmers believe” style essay focused on LANs, challenging assumptions developers often make about local networks. It highlights that local networks can be unreliable, heterogeneous, misconfigured, segmented, hostile, or behave differently than expected.

As more software depends on discovery, peer-to-peer communication, edge devices, and home or office networking, LAN assumptions increasingly become production risks. The piece underscores a broader trend: developers need to treat even “local” infrastructure as variable and potentially untrusted, not as a simple fast pipe.