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When Wifi goes down: Transfer files from Air gapped machines using QR codes
- coreyp_1 11y agoThis is a beautiful idea. How much information does the QR code carry, and how much is transfer boilerplate?
- leonjza 11y agoAuthor here. The amount of data per QR depends on the QR size specified. If I remember correctly, its about 10 bytes per code in the default config (QR code size of 30). Transfer boilerplate is a few codes in the start to setup the conversation and a FIN like message at the end.
- th0br0 11y agoThe maximum storage capacity seems to be 2953 bytes ([1]). Although that's with error correction level L, so you can only read it as long as you have 93% of all codewords. [1] https://en.wikipedia.org/wiki/QR_code#Storage https://en.wikipedia.org/wiki/QR_code#Storage
- padde 11y agoThis is cool. I guess with high density QR codes, a decent display and a good cam you could transfer a megabyte or more in a minute :D If both devices have front facing cameras, such as smartphones, you could even have a real-time back channel (duplex), and the receiving device could signal the sending device that a certain "frame" got lost and needs to be retransmitted.