Rahul Mehta Gandhinagar LsCandidate

A software question for software people and recallists
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Say an auction for plot is to be held.
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Say there are 50 bidders say P01 to P50.
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Say final date for auction is say 30-nov-2016 5pm.
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Each bidder will be allowed to send multiple bids and his last bid will be taken as final bid from him, and previous bids will e deemed cancelled.
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So what paper or digital mechanism can be used so that no bidder can know how much is other bidder putting.
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eg say sealed envelope are used. Then say P01 sends a bid in sealed envelope. If the staff is corrupt, they can open the envelope and inform other bidder who is paying bribes abut P01's bid. IOW, sealed envelope is good only if staff is non corrupt
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Also, staff can change the contents of envelope and then we have endless litigation of who did what.
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Of course, NT = narcotest can be used. But see if a non-NT solution is possible. NT is good, but should be avoided as far as possible,
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Also, is staff of P01's leaks information, then it is NOT a problem we have to solve. We have to only worry that P01's bids dont get stolen from govt office.
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Now simple digital solution will also not work. Say each P01 to P50 are asked to give bids via internet on govt server. Then admin of server can leak P01's bids to others.
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So what protocol or method do you propose?

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