Re: Mikes request that we identify an upper limit on the number of digits

Hi Mike

The issue with coping discussed in different user groups.  We have also discussed it in  the issue paper on In addition to this we have the comments from members in the task force who often struggle with copying. My experience of disabilities such as dementia is that trouble will start at 2 or 3 digits, and hence any useful number will bar people  who can still use sites like youtube or netflixs. So researching this proposal doesn't really appeal to me unless there is a strong consensus to go here. 

If having a limit is needed to get this at this SC though, they it is a compromise position that we may have to do but  will exclude some people from using the site at all. We may have to do that, but I would much rather not.

All the best

Lisa Seeman

LinkedIn, Twitter

---- On Tue, 28 Nov 2017 16:52:59 +0200 Michael Gower<> wrote ---- 

> For example a code with five digits is both too high  for accessibility 

One of the issues IBM opened against this SC is that to date you have supplied no data to support this statement, or to support the notion that transcription represents an impediment significant enough that an SC is warranted to entirely prevent its use to satisfy authentication. As mentioned in Issue #442 the only study cited so far was a study that showed that every participant was able to transfer 5 digits. So why keep repeating that 5 is too high?

I identified the concern to you last November and the concern about prohibiting copying was flagged and discussed back in April. Issue 442 has been open since October 8 with no response. This concern is not coming out of the blue, nor am I the only person to voice it.

Other considerations include identifying thresholds and relying on assistive technologies to augment experience to satisfy individual users needs. As an example, look at the thresholds for Contrast (Minimum). The SC demands a certain level of contrast for content. That is not going to satisfy the needs of all users, but based on a bunch of analysis and data, a threshold was established, with the assumption that a user who requires more contrast is going to call on an AT to augment.

My expectation would be that based on data, we would be looking at something similar for guidance on allowable transcription. If we don't have that data, then we are basing this SC on anecdotal evidence -- and as others have identified, it's an SC with far-reaching ramifications.

The new Animation from Interaction SC, designed to address vestibular disorders, had its timing parameters removed and its designation as a double AA moved to a triple A category because there was insufficient data to establish enforceable thresholds.

Michael Gower
IBM Accessibility

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From:        "lisa.seeman" <>
To:        "W3c-Wai-Gl-Request@W3. Org" <>
Date:        2017-11-28 12:45 AM
Subject:        Mikes request that we identify an upper limit on the number of  digits

Hi Folks

Mike had requested empirical evidence for what is the maximum number of digits that can be reliable copied form a device for multi factor authentication.

I am looking into it, but I actually think we should not enforce a  limit in the number of digits. Enforcing a limit on the number of digits in a security code will definitely jeopardize security. For example a code with five digits is both too high  for accessibility and lower then most secure applications would require.  It is much better to give the user an option of sending the code to the computer via Bluetooth/ token or even QR code. 

Please let me know if we want to go this rout. If not it is a lot of research for nothing. 

in the mean time Neil found some more research on sequencing problems that is useful in case we decide we would want to go in Mike's direction.

All the best

Lisa Seeman

LinkedIn, Twitter

Received on Tuesday, 28 November 2017 16:51:09 UTC