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A comment on Cryptographic Right Answers. Parent comment

Re:Cryptographic Right Answers by lvh on Tuesday April 03, 2018 @05:43PM (#16749609)
It's not always a foregone conclusion that it scales better. I've seen people argue that when using ECDSA verification that's 4x longer than an in-DC RTT. Usually: DB kv lookups aren't even close to the most expensive thing your app does.

Generally: don't do encrypted tokens. If you must: don't do JWT for this. Just secretbox a thing and be done with it, or use PASETO[0].

[0]: https://github.com/paragonie/paseto

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Re:Cryptographic Right Answers by iamwil on Tuesday April 03, 2018 @05:57PM (#16749737)
By secretbox, I assume you mean NaCl's secretbox. Cool, thanks for the tips, and helping make the web a more cryptographically secure place.
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Re:Cryptographic Right Answers by ketralnis on Tuesday April 03, 2018 @06:14PM (#16749881)
> Generally: don't do encrypted tokens

Can you point to a RTFM on why not? I'm sure it's a big list of reasons but where can I read about the biggest one?

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Re:Cryptographic Right Answers by lvh on Tuesday April 03, 2018 @06:26PM (#16749952)
Because they cause more problems than they solve.

A lot of the implementations _aren't even faster_, but the laundry list of security bugs they have caused is very real. Suddenly you get to worry about irrevocable tokens in order to solve scaling problems you don't have.

A good intro is: http://cryto.net/~joepie91/blog/attachments/jwt-flowchart.pn...

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Re:Cryptographic Right Answers by iamwil on Tuesday April 03, 2018 @09:15PM (#16751033)
from: http://cryto.net/%7Ejoepie91/blog/2016/06/19/stop-using-jwt-...
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