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Robustness principle in all things

If you are at all technically inclined, the Tailscale blog is a great joy to read. I try to cultivate and attitude of bemused fatalism about the state of technology as a survival mechanism and the folks at Tailscale strike that tone very well.

Things are complicated. The social and commercial effects of computer networks outran the standards. Besides, no matter how well the standards are designed, there are going to be some engineers / companies that just don’t give a shit and will stop thinking about the problem as soon as they get something half-ass working.

As a result, network protocols are typically built following the robustness principle (also know as Postel’s law):

Be conservative in what you send, be liberal in what you accept

There are benefits from strict adherence to protocol in the systems you control, but you can’t force strictness on others. As Avery Pennarun says in this post on IPv6 (emphasis mine):

Postel’s Law is the principle the Internet is based on. Not because Jon Postel was such a great salesperson and talked everyone into it, but because that is the only winning evolutionary strategy when internets are competing. Nature doesn’t care what you think about Postel’s Law, because the only Internet that happens will be the one that follows Postel’s Law. Every other internet will, without exception, eventually be joined to The Internet by some goofball who does it wrong, but just well enough that it adds value, so that eventually nobody will be willing to break the connection. And then to maintain that connection will require further application of Postel’s Law.

In 2021, this reads as good life advice, not just technical advice. There’s so much weird mess out of my control. Where I have the opportunity for positive influence, I’ll use it every time, but then I’ll still have to share the same goddamn planet with QAnon dumbasses and people who will refuse COVID-19 vaccination. There’s no designed-from-scratch system that could provably work better or feasible migration path from the system we have now, but we can at least build pockets of functional governance and outcompete on value. That’s the best I’ve got.