of view in 1980 as an idea that he thought should characterize the architecture of the Internet. “Be conservative in what you do, be liberal in what you accept.”131 Postel’s idea became known as the “robustness principle” and it was meant to determine how switches and nodes on the net should behave. They should, Postel felt, be good at handling lots of different types of communications - they should be “robust” — but they should also be careful not to spread too much non-standard garbage out into the networks. This was an essential advance over the old ARPANET Paul Baran had helped inspire. That system worked wonderfully by itself, in isolation, as it sent humming nuclear launch codes zipping around, but it struggled when it needed to interoperate with other networks. It wasn’t generous. The Internet that Postel and others were designing was intended to be much, much larger than ARPANET, so an ability to speak to others and be understood was essential. It was like planning an airport: You wanted to be able to land lots of different types of planes. But if someone started throw golf balls, jello and gasoline on the runway you'd have a problem. It would slow down the system for everyone. Postel was telling engineers: Be careful what you do and what you put onto the system. Take responsibility on your end. Build something that’s generous in what it will handle from others. Be liberal in what you accept. From the first moments on the grass in Lelystad, the small town just outside Amsterdam where the Hacking At the End of the Universe conference gathered, the mad diversity that this idea suggested was an astonishing, delightful fact. As broad and strange a group as Rop’s email had hinted might come was in fact there, under the trees, happily running cables from tent to RV, powering their connected routers with gas-fired generators, marveling at data transmission speeds that today, your phone might manage from an underground garage with the barest connectivity. The two-da