5238cda077
Also, needed to understand Byzantine fault tolerant paxos better. Still do not.
83 lines
3.8 KiB
HTML
83 lines
3.8 KiB
HTML
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<head>
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<meta http-equiv="content-type" content="text/html; charset=UTF-8">
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<style>
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body {
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max-width: 30em;
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margin-left: 2em;
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p.center {text-align:center;}
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</style>
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<link rel="shortcut icon" href="../rho.ico">
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<title>Electronic Wallet</title>
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</head>
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<body>
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<p><a href="./index.html">To Home page</a> </p>
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<h1>Electronic Wallet</h1>
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<p>We are moving towards a system where people use a cell phone as their
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wallet, or a smart card with screen and some buttons.</p>
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<p>A cell phone is used two handed, one hand holding it, one hand pressing the
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buttons. A dedicated wallet would be used one handed, held by one’s palms and
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fingers, with a thumb click accepting or rejecting a transaction. The dedicated
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wallet would be able to talk to any other wallet, or to one’s cell phone, or
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indeed any cell phone, if touched to it, or nearly touched to it.</p>
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<p>The wallet communicates primarily by near field communications, the wireless
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equivalent of whispering in someone’s ear. Nearfield is a communication method
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that guarantees that the entities communicating are very close together – with
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radio you want the greatest possible range, but nearfield is for those
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situations where for security reasons you want the least possible range.
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Nearfield is radio with the antenna twisted to pick up the quadrupole field and
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ignore the dipole field. Ideally, an near field communication chip should only
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be able to talk to something that is almost touching, and it should be
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impossible to eavesdrop from more than a foot or so away. </p>
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<p>This device should function wallet, as car key, atm card, credit card,
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computer login device, and employee door opening device. It enables you to
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login to websites.</p>
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<p>To buy groceries, you would touch the device to the cash register, the cash
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register would show it was asking for a certain sum of money, the device would
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show it was being asked for that sum and vibrate or beep, you would thumb
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acceptance, and money would be transferred to the cash register, and a receipt
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transferred to the wallet.</p>
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<p>Money would be represented to the user as if it was a tangible object that
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could reside in the wallet, in the cell phone, or in an account. One’s cell
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phone can transfer money between these places, with the transfer taking a short
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but finite time – money leaves one account before it arrives in another
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account.</p>
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<p>The device would also handle non monetary receipts – you put your coat in
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storage, you get a receipt that enables you to collect it back again.</p>
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<p>Of course if the wallet is thumb controlled, it is as easily stolen as a
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real wallet, or real keys. A cell phone functioning as a wallet can be made
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resistant to theft.</p>
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<p>A *spoken* passphrase is both something I know, and something I am. Of
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course someone could unobtrusively record it – but he would need to record it
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*and* steal the phone. Easy to do one, easy to do the other, not quite so easy
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to do both.</p>
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<p>Further, a spoken passphrase can comply with the principle of Not One Click
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for Security. You set up the user interface so that speaking the passphrase is
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used in place of clicking OK. </p>
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<p>The way the that the user interface should work, is that the smartphone has
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speech recognition and NFC. To authorize payment, or login, or whatever, you
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bring the smartphone close to the NFC device, for example the cash register.
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When the NFC handshake is complete, the phone makes a beep and displays the
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proposed transaction, and then you speak the magic passphrase for that
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transaction.</p>
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<p style="background-color : #ccffcc; font-size:80%">These documents are
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licensed under the <a rel="license" href="http://creativecommons.org/licenses/by-sa/3.0/">Creative
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Commons Attribution-Share Alike 3.0 License</a></p>
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</body>
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</html>
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