Re: [DNSOP] RSASHA512 SHOULD-
"Paul Hoffman" <paul.hoffman@vpnc.org> Fri, 08 April 2016 19:45 UTC
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From: Paul Hoffman <paul.hoffman@vpnc.org>
To: Francis Dupont <Francis.Dupont@fdupont.fr>
Date: Fri, 08 Apr 2016 16:44:58 -0300
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Subject: Re: [DNSOP] RSASHA512 SHOULD-
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On 8 Apr 2016, at 10:46, Francis Dupont wrote: > In draft-wouters-sury-dnsop-algorithm-update-01.txt the RSASHA512 > (code 10) DNSKEY/RRSIG algo got a SHOULD- for DNSSEC signing. > The argument is it is not currently heavily used but I am afraid > it is not a very good argument. > I have a question for cryptographers in the list: as far as I know > there is a relationship with the RSA key size and the output length > of the hash algorithm. So perhaps we should not plan to move > RSASHA512 to MAY (or worse to MUST NOT) as the SHOULD- means, > i.e., put a SHOULD (vs SHOULD-) for RSASHA512? There is a relationship between the effective strength of the key (RSA or EC) and the length of the output. If you are using 20,000-bit RSA keys, SHA512 might be appropriate. If you are using 4096 bit or shorter RSA keys, SHA256 is sufficient. --Paul Hoffman
- [DNSOP] RSASHA512 SHOULD- Francis Dupont
- Re: [DNSOP] RSASHA512 SHOULD- Paul Wouters
- Re: [DNSOP] RSASHA512 SHOULD- Evan Hunt
- Re: [DNSOP] RSASHA512 SHOULD- Paul Hoffman
- Re: [DNSOP] RSASHA512 SHOULD- Paul Wouters
- Re: [DNSOP] RSASHA512 SHOULD- Evan Hunt
- Re: [DNSOP] RSASHA512 SHOULD- Paul Hoffman