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About : the problem : a false sense of security
RightWe agree, the value of a simple visual verification is low, but the value of a global anti robot system is very high.
About : A hierarchy of needs
In our point of view, web sites implement visually oriented anti-robot tests to preserve their ressources for human users, and therefore, we think checking user humanity is the major issue.
About : privilege
We don't think this one adds value to the paper : implementing security or preserving privilege for certain user are synonymunderstand preserving priviledge and preserving ressources as the same notion. This echoes back to the global need, which is to preserve ressources by checking on user humanity.
Security without privilege is useless, preserving privilege implies implementing security.
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This concerns two very different problems and thus should be treated as is.
Robots can have identity, and yet consume web site ressources (ex: having identified bots make several hundred reservations per minute on a train ticket reservation site)
These two notions seem different. We view captchas as a response to the need for preserving priviledges and ressources for human users.
Accessibility of humanity tests (Turing tests) is the subject we are interested in, not accessibility of identity systems.
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