DSA vs RSA vs ECDSA vs Ed25519
https://nbeguier.medium.com/a-real-world-comparison-of-the-ssh-key-algorithms-b26b0b31bfd9
With OpenSSH, NIST curves are used for ECDSA (generally NIST P-256), and according to the article Security dangers of the NIST curves, it is very likely that an NSA backdoor is hidden there. If the NSA can already crack it, then it won’t be as hard to crack for somebody else…
Ed25519 is quite the same, but with a better curve (Curve25519).
めも、未検証
Security dangers of the NIST curves
http://www.hyperelliptic.org/tanja/vortraege/20130531.pdf
https://sig9.hatenablog.com/entry/2020/01/11/000000
Ed25519対応鍵長:256bitのみ
鍵の作り方
# ssh-keygen -t ed25519
RSAとDSAの違い
https://gunshot.hatenablog.com/entry/20150917/p2
OpenSSHのHostKeyにED25519を追加
https://matoken.org/blog/2016/02/28/add-ed25519-to-openssh-of-hostkey/
Host key verification failed.
$HOME/.ssh/config
StrictHostKeyChecking no
