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Joined 1 year ago
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Cake day: July 10th, 2023

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  • If your average house only has one person showering at a time an 18 kW 3.51 GPM Tankless Electric Water Heater would work. It would cost about $500.

    To replace that with Keurigs would take some work. They draw 900 to 1500 watts depending on model. So it would take between 20 and 12 Keurigs to match the power draw. I’m not sure what the inlet/outlet tubing diameters are but it seems some replacement parts labeled 1/4" so that’s half a gallon per minute max. You’d need 7 or 8 running in parallel to move enough water. Probably 21 900 watt Keurigs running in groups of 3 would come closest.

    I estimate about $2000 in Keurigs plus another few hundred dollars in fittings and a lot of time to reproduce a purpose built $500 water heater.

    And of course Keurigs break frequently and you’d definitely void any warranty.

    Good luck!




  • I’m a bit behind on password specific hashing techniques. Thanks for the education.

    My background more in general purpose one way hashing functions where we want to be able to calculate hashes quickly, without collisions, and using a consistent amount of resources.

    If the goal is to be resource intensive why don’t modern hashing functions designed to use more resources? What’s the technical problem keeping Argon2 from being designed to eat even more cycles?



  • I was incorrect about the goal being minimal resources. I should have written that that goal was to have controlled resource usage. The salt does not increase the expense of the the hash function. Key stretching techniques like adding rounds increase the expense to reach the final hash output but does not increase the expense of the hash function. High password length allowances of several thousand characters should not lead to a denial of service attack but they don’t materially increase security after a certain length either.


  • I was incorrect but I still disagree with you. The hashing function is not designed to be resource intensive but to have a controlled cost. Key stretching by adding rounds repeats the controlled cost to make computing the final hash more expensive but the message length passed to the function isn’t really an issue. After the first round it doesn’t matter if the message length was 10, 128, or 1024 bytes because each round after is only getting exactly the number of bytes the one way hash outputs.





  • For my own projects I buy whatever Supermirco platform the data center manager has a volume discount for or I find used Dell equipment from third party sellers or ebay.

    At work we rent by the month based on needs and availability. I never know the brand, just the specs. Lately AMD based servers have been more competitive.