Smart card wallet

This pages gathers resources for the implementation of a Bitcoin wallet on a smart card.
===Rationale===
*Computers and smartphones are target for malware. The software on a smart card can be protected.
*Smart cards do not need a battery, nor internet connection, they are robust.
*Adoption: people are already used to paying with smart cards.
===Desired features===
*no blockchain, no node; the card contains only private keys, and an algorithm to sign a transaction
*the smart card should have its own keyboard (for pin code protection) and display (to show the transaction amount)
(<- Alternative to this is the card returning, to the terminal screen, the debit amount multiplied by a number only the card holder knows which cycles from 1 to 100 to 1 incrementing by 1 each transfer - the card is locked 10 minutes if a second amount is send before a pin is typed.)
* The card holder will know pin, puk, private key and address only from when he programmed it or ordered his smart card.
*the card should implement a deterministic wallet, so that funds can be recovered if the card is lost.
===Usage scenario===
* the reading device may belong to a merchant at a point of sale; it cannot be trusted with private keys. 
* the reading device is connected to a full bitcoin node; it can be trusted for getting and sending blockchain information.
* the reading device sends to the card the current balance of its bitcoin addresses. This information can be cached in the card.
* the reading device sends a bitcoin receiving address and transaction amount to the card.
* the amount is displayed by the card ; the user confirms the transaction with his pin code.
* the smart card creates a signed transaction and sends it to the reading device
* the transaction is checked and broadcast by the bitcoin node.
==Implementation steps==
===1. write a bitcoin daemon that can talk to a lightweight wallet===
*this has been done already, see for example bitcoinjs: https://github.com/bitcoinjs/bitcoinjs-lib
*See also this pull request: importexporttx can be used to broadcast the transaction
* https://bitcointalk.org/index.php?topic=28278.msg383312#msg383312
===2. write a lightweight wallet===
*wallet without blockchain, in order to test the daemon
*this lightweight wallet will be later implemented on the card 
*use it to define the communication protocol between card and reading device.
update: this is done, see Electrum
===3. implement wallet on a simple smart card===
* http://www.opensc-project.org/opensc openSC : tools and libraries for smart cards. 
* amadousarr.free.fr/crypto/ECDSAJAVACARD.pdf : A Software Implementation of ECDSA on a Java Smart Card
* http://www.acs.com.hk : cards, readers, development kits; no display, pincode needs to be typed on the reading device
* http://www.basiccard.com/index.html?overview.htm : Smart Card (ZC7.5) which contains RSA/EC and DES/AES coprocessors. Used in an implementation of the OpenPGP Card 2.0 standard (http://g10code.com/p-card.html)
===4. implement wallet on a smart card with display and pincode ===
list of vendors:
* http://www.nidsecurity.com/products/solution-enterprise.html (smart cards with LCD displays)
* http://www.avesodisplays.com/ (smard cards with flexible displays)
==references==
*https://bitcointalk.org/index.php?topic=7539.0 Bitcoin smartcard Point of Sale terminal
*https://bitcointalk.org/index.php?topic=20933.0 Bitcoin and Smart Cards 
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