Re: [Cbor] Use and development of draft-faltstrom-base45 (was: Re: CBOR in QRcodes)

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 25 June 2021 15:51 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: 'Christian =?us-ascii?Q?=3D=3Fiso-8859-1=3FQ=3FAms=3DFCss'=3F=3D?= <christian@amsuess.com>, Doug Ewell <doug@ewellic.org>, cbor@ietf.org
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Date: Fri, 25 Jun 2021 11:51:45 -0400
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Subject: Re: [Cbor] Use and development of draft-faltstrom-base45 (was: Re: CBOR in QRcodes)
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I don't have enough caffeine in me to figure out how much more efficient
base45 is over base32.  I think it's log(45)/log(32), right?

In places where base64 or base85 won't work, it seems to me that base32 is
probably safer than base45.   As I wrote, I think that the limitation for
QRcode entry has to do with forms on web pages or 3270 terminals, where the
scanner is a bump-in-the-cord on the keyboard interface.  Whether it's a
PS2/PS2 or a second USB input.

I'm surprised that base45 includes space, + and / :-)

--
Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide