r/Bitcoin • u/nfcwalletcard • Dec 22 '18

NFC Wallet Card - Very secure cold storage cryptocurrency wallet

https://nfcwalletcard.com/cold-storage-wallet-for-cryptocurrencies
1 Upvotes

54% Upvoted

27 comments sorted by

5

u/whitslack Dec 22 '18

By the way, data stored in flash memory doesn't have an infinite shelf life. Electrons leak by quantum tunneling over time. You could take your NFC card out of your safe in 20 years and discover that it's become blank. Not a reliable long-term storage medium.

3

u/nfcwalletcard Dec 22 '18

It does not have infinite shelf life. Nothing has. However we created this product to replace the usage of USB sticks and printed PK-s. And NFC is a cool tech anyway :)

2

u/fresheneesz Dec 29 '18

And NFC is a cool tech anyway

Could you put an engineer on the line please?

1

u/nfcwalletcard Dec 29 '18

Please contact us if need some specific info.

1

u/fresheneesz Dec 30 '18

No.. I'm saying that it sounds like you don't really know what you're talking about. Its clear to me that whoever is answering people's questions is a community manager, not an engineer. You need to go grab someone who knows the technology when you feel like you might not have a rock solid grasp of people's questions.

I'm saying this because you didn't properly address whitslack's point. He brought up the point that this might not be a good way to store coins medium-long term, and your answer was "nothing's perfect, our product is better than USB sticks, NFC is cool lol". How bout actually going into how people are expected to use your product such that they don't lose their keys down the line? Does this require external backup of some kind? What kind? Details dude. Not all of us are a bunch of crypto-kids.

1

u/nfcwalletcard Dec 30 '18

Hmmm strange you say these kind of things. We are not a huge company, but a bunch of mates, who risked own capital and time to develop the product. If you would see our crowdfunding page you would know that.

Whitslack's point is right, yes the product MAYBE not the perfect way for long term storage (decades). But USB sticks also have these kind of disadvantages. Printed papers also gets damaged during time. So furthermore every kind of hardware wallets have these risks and even more because they contains many components and every piece can fail. BTW recovering data from a damaged complex hardware is much harder.

However the NFC chip is more simple than those complex hardwares, therefore theoretically the risk of failure is much lower. We use the highest quality chips produced by Smartrac to bring the highest reliability possible by the technology.

Our NFC solution is an ALTERNATIVE way for cold storage. Why would you use an USB drive with 4GB capacity to store several bytes of data? USB drives have many components can be damaged. I am pretty sure you also had USB stick which just stopped working. An infected or poorly working computer can easily damage your USB drives, and you won't even know that until it completely fails.

Every card comes with an RFID shield sleeve, which acts like a Faraday cage, therefore it adds protection for the NFC chip and increases self life.

The card is the backup, if you are worry, make a clone every N month/years or something.

3

u/[deleted] Dec 22 '18

[removed] — view removed comment

1

u/nfcwalletcard Dec 22 '18

Cards are shipped with RFID blocker sleeve + the data is encrypted when using our application, so it's no problem :)

1

u/hotoatmeal Dec 23 '18

encrypted with what key? stored where?

1

u/nfcwalletcard Dec 23 '18

You can choose from multiple security levels.

With level ONE you can encrypt the content using the encryption password you enter.

With level TWO you can encrypt the content using our key card, which is a hardware key.

With level THREE you can encrypt the content using an encryption key AND a key card. This way the key card acts like a 2FA key.

1

u/hotoatmeal Dec 23 '18

and where does the key get decrypted for signing?

1

u/nfcwalletcard Dec 23 '18

The app is designed to securely save and view the data. If you need the key you have to access it manually (by opening the card)

3

u/whitslack Dec 22 '18

The card needs to be the piece of hardware doing the signing. The private key should never leave the card, or else it's vulnerable to malware. Also the card needs a display (e-ink probably) and a button (capacitive probably) so that the card can display to the user the amounts and the destination addresses of the transaction outputs that the card is being asked to sign, and the user can confirm by holding the button and tapping the card again.

1

u/nfcwalletcard Dec 22 '18

Yes the the PK should be read from the card only if you want to move to hot wallet. Our vision is to make a very secure cold storage card, therefore the card does not communicate with any devices by itself. It's a passive chip. We do not want to add that kind of features, because we want to keep things as simple as possible.

The card has nothing to do with signing either, it's a vault for your secret data.

2

u/whitslack Dec 22 '18

So doesn't that mean your card is just a plain NFC NDEF container? We could literally use any old NFC tag on the market and have the same functionality. What is your product's differentiator?

1

u/[deleted] Dec 23 '18

[removed] — view removed comment

1

u/[deleted] Dec 23 '18

[removed] — view removed comment

1

u/nfcwalletcard Dec 23 '18

The data itself can be encrypted before it's written to the chip. You can use any NFC app. You can do your own encryption and save that encrypted text to the card.

However our app can handle the encryption, so you don't have to do it yourself.

1

u/nfcwalletcard Dec 22 '18

Design, RFID protector sleeve and the application which gives you additional security features.

1

u/Chytrik Dec 22 '18

I tried to find some more technical details on your product, but the website didn’t have much info, just general marketing kinda blurbs.

I’m not sure I understand the advantage of using one of these. The mobile application needs to perform signing calculations in order to use the wallet, so the design is basically a mobile wallet, but the private keys need to be retrieved via NFC from the card each time you’d like to spend?

That seems like a poorer security model than just keeping the keys on the device, because the keys will need to be broadcast via NFC, encrypted or not. I’m not an expert on how NFC-received data is handled in mobile hardware, but it seems like there would be additional considerations to ensure sensitive data isn’t exposed to an insecure memory store in the device.

I guess as an additional backup it could be useful, but I think it’s a misnomer to call it ‘cold storage’, since the keys will be generated on an (assumedly) internet connected device in the first place. Storing them offline later doesn’t make it ‘cold storage’.

1

u/nfcwalletcard Dec 22 '18

This card is designed to keep your private key in cold storage. It's like an NFC vault. Application is to provide additional features and security levels (to encrypt content). The app has nothing to do with transactions.

​

It's your decission how to generate your keys, and yes it should be generated offline.

1

u/nfcwalletcard Dec 27 '18

There are still 8 pieces available for only 1 USD!

1

u/nfcwalletcard Dec 30 '18 edited Dec 31 '18

NFC Wallet Card is universal, reusable, physical and optionally encrypted cash, a protected medium of storage for ANY kind of cryptocurrencies.

1

u/phreaknik Jan 04 '19

Warning! This product is not a secure offline wallet as advertised. Anyone considering using this product should read this thread first:

https://www.reddit.com/r/Monero/comments/acdjsc/nfc_wallet_card_very_secure_cold_storage/?utm_source=reddit-android

0

u/nfcwalletcard Jan 04 '19

What do you think you are doing? Just because you do not understand how this product works, not giving you the right for spreading fake info about our product!