On Tue, 4 Aug 2015, Jiankang Yao wrote:
I just read this draft.
Note we are changing that part of the draft to use another mechanism instead of hashing.
Question: 1, why should it be hash truncated to 28 octets ? why choose 28 not other numbers?
It was to match the length of the previous draft's sha224 version. That algorithm wasn't available on all platforms (eg Microsoft) so it was changed to sha256 but truncated. Truncation was to make the labels smaller and more managable.
2,since some local-parts are longer than 28 octets, are there some collisions after hash truncated to 28 octets ?
I think if you have 100.000 email addresses in one domain, the chance of collision would be pretty small. but non-zero. anyway, we will use base32 split encoding in the next version of the draft. Paul _______________________________________________ dane mailing list dane@ietf.org https://www.ietf.org/mailman/listinfo/dane
