[seems to have accidentally moved off list] Passwords for TCP-MD5 and TCP-AO do not have to be remembered, and they are configured by experts who know they should be random.
On 12 September 2025 13:31:03 CEST, Vasilenko Eduard <[email protected]> wrote: > * You will see that the number of random letters is very very important. >For sure, very important, every letter is 75x. >But nobody would be capable of remembering even 8 random letters. People would >continue to choose not very strong passwords. >It is possible to fight with people or help them with technology that would >not need such strong passwords. >The IT world has chosen the latter. Many smart people have participated in >this – I do not believe that they have forgotten to account for something. > >And do not forget that for the process of brute force, the password >“7Jon%Brain&Letter” (17 letters) is weaker than “n4H*h!s$” (8 letters). >I mean: there is a way to downgrade too, even for long passwords. > >Only full automation when passwords are not appointed manually permits raising >the bar of password complexity. >Eduard >From: [email protected] <[email protected]> >Sent: Friday, September 12, 2025 13:33 >To: Vasilenko Eduard <[email protected]> >Subject: RE: MD5 is too fast > >You did 10 random letters with 8 5090s and you calculated 19 days. > >Have you calculated 12 random letters? 16 random letters? 24 random letters? >40 random letters? > >You will see that the number of random letters is very very important. > >On 12 September 2025 09:53:36 CEST, Vasilenko Eduard ><[email protected]<mailto:[email protected]>> wrote: > >I hope I have answered in the thread. >If not, ping me. >Ed/ >-----Original Message----- >From: nanog--- via NANOG <[email protected]<mailto:[email protected]>> >Sent: Thursday, September 11, 2025 18:17 >To: North American Network Operators Group ><[email protected]<mailto:[email protected]>> >Cc: [email protected]<mailto:[email protected]> >Subject: RE: MD5 is too fast > >Have you calculated how long it should take to test all 80-bit passwords? >200-bit passwords? 2000-bit passwords? > >Suppose that a good server can try about a billion passwords per second. How >long do you think it takes to try all the passwords? > > >On 11 September 2025 12:18:00 CEST, Vasilenko Eduard via NANOG ><[email protected]<mailto:[email protected]>> wrote: > >The simple integer division on the processor takes something like 40 cycles >(fast). Hence, the factorization challenge should have thousands of bits. Then >it is going to take millions of years for one processor to try all >possibilities. > >If the password is just 12 letters (80 bits?), then the time to test the >password should be longer. Or else the good processor would try all >combinations for a limited time. >Of course, a longer password would help a lot, but even 200 bits is not 2000. >The check should be proportionally slower. >It is especially a problem when we are dealing with predictable passwords >based on human language words. > >Maybe SHA-2/3 have not been developed with "slowness" as a goal. It may be >that only randomness was the target. Hence, so many assembler instructions for >one round. >But only the slowness permits its use for HMAC or the password fingerprint >that you have discussed before. >I could not believe that slowness is just a byproduct of randomness. It is so >evident why it is needed by itself (for some applications). >Ed/ >-----Original Message----- >From: Thomas Bellman via NANOG ><[email protected]<mailto:[email protected]>> >Sent: Thursday, September 11, 2025 12:03 >To: North American Network Operators Group ><[email protected]<mailto:[email protected]>> >Cc: Thomas Bellman <[email protected]<mailto:[email protected]>> >Subject: Re: MD5 is slow > >On 2025-09-11 09:23, Vasilenko Eduard via NANOG wrote: > >SHA-2 and SHA-3 are used not only for networking, they are general. >Hence, they were developed to be slow enough to prevent brute force >for some other applications. > >Since you are asserting that the hash functions must be "slow" in order to >resist brute force attacks, could you perhaps give us an estimate of *how* >slow they must be? And how you arrive at that (e.g. how much resources does >the attacker deploy, and how long walltime do you give the attacker)? > > > /Bellman > >________________________________ > >NANOG mailing list >https://lists.nanog.org/archives/list/[email protected]/message/SZV >2BS2WTBZIF5TOK43UQ4GYGNSB4QVX/ > >________________________________ > >NANOG mailing list >https://lists.nanog.org/archives/list/[email protected]/message/S3YL6WSDA3K2ZWEKYBOOQPRVAQSYYNJX/ _______________________________________________ NANOG mailing list https://lists.nanog.org/archives/list/[email protected]/message/347WMC4UYSTOCGIQJZAC7GHZCOT7KJJX/
