MSC4227: Audio based quick login

[albertotirla]

Rendered

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This MSC gives visually impaired people a way to use the quick login mechanism, without having to scan a QR code, which is impossible to do reliably with any current assistive technologies

[thoraj]

While I agree with goals of this MSC, I'm very doubtful it will work as specified.

• the use of morse code seem strange. Since morse code was invented, there have been numerous innovation of more efficient ways to transmit information over audio channels (FSK, DTMF or more advanced QAM methods)
• the transmission must most likely use some form of error correcting code to get the desired accuracy
• transmitting in the band 50khz-80khz (ultrasound) will be hard/impossible with standard phone hardware. Android samples at 44,1khz or 48khz afaik, which theoretically limits bandwidth to 22khz or 24khz (Nyquist limit)

Using more proven methods and protocols rather than inventing something new, seems more likely to succeed .

[albertotirla]

I will look more indepth at FSK, because this one seemns quite promising. The problem is, as always, if we have bindings for this protocol for at least as many programming languages as we have matrix sdks. I looked at something similar before, and the problem with all these is that we don't have enough bindings for this stuff as we have for qr code generation and scanning, which is probably even less than other methods.

[turt2live]

Implementation requirements:

• Client
• Server

[albertotirla]

server is not required, this is a protocol between two clients which requires no API endpoints on the part of the homeserver