Re: [secdir] [Last-Call] Secdir last call review of draft-ietf-netconf-crypto-types-20

[Valery Smyslov <[e-mail]>]

Spotted a typo in own message – of course it was meant Quantum computer, not a Post Quantum one

(I have no idea what Post Quantum computer may mean :-), I know only Post-quantum cryptography).

 

 

In addition, the requirement, that "Implementations SHOULD fail the write-request if ever
the strength of the private key is greater then the strength of the
underlying transport" looks wrong to me. You don't need to have
1024 bits transport protocol strength to transfer 1024 bit key, since
even for say 256 bits it's infeasible to break.

 

IDK about this.  Again, I saw this constraint once in a DoD setting.  

 

          My (another) point was that there is generally no point to increase

          security strength beyond some level. Currently it is believed

          that 128 bit of symmetric key is infeasible to break (provided the algorithm is not broken itself),

          If you are lucky have full-sized Post Quantum computer, it’ll be 256 bits.

          It’s enough to transfer symmetric keys with say 1024 bits of entropy

          (FWIW). So the requirement that the strength of transport must

          be always greater than the strength of transported key 

          seems not a good requirement to me. Instead require that

          the strength of transport be sufficient to make

          infeasible for an attacker to break it.