3 ms·

I'm fairly certain it's baked into the chip or part of the firmware which is not easily writeable, which is why the wake words are static. One can check if a d

by illvm 8y ago

I'm fairly certain it's baked into the chip or part of the firmware which is not easily writeable, which is why the wake words are static. One can check if a device is compromised or not behaving as expected fairly easily by monitoring network traffic.

felix_nagaand 8y ago
Obfuscating the data would be no more difficult than obfuscating tor traffic by delaying, stuffing, and merging packets. Has anyone done a long term packet analysis of an echo, home, iPhone, pixel, or galaxy?
comex 8y ago
As far as I know, the hotwords are static because the detector uses a neural network pretrained specifically for those words. Training a new network for a custom hotword would require way too much training data. While it would be possible to instead use a generic network that decodes any type of speech – like it does when in full speech-to-text mode – and then use the outputted representation to compare to a custom hotword, that would be far more compute and power intensive, whereas the specialized network is relatively small. (The specialized network is also probably more accurate.) At least on battery-powered devices, more power usage for something that‘s always running is a dealbreaker. The same pressure doesn’t necessarily apply to home devices that are always plugged in, but all of the major in-home voice assistants also run on phones, and the providers probably prioritize a uniform user experience across devices. Disclaimer: I could be completely wrong, and/or the situation could change over time due to improved hardware and software. There was a rumor earlier this year that the Google Assistant might add custom hotword support in the future: https://9to5google.com/2018/01/29/google-app-7-20-assistant-apk-insight-teardown/ https://9to5google.com/2018/01/29/google-app-7-20-assistant-... Main source: Apple’s article about “Hey Siri”: https://machinelearning.apple.com/2017/10/01/hey-siri.html https://machinelearning.apple.com/2017/10/01/hey-siri.html

by illvm 8y ago

felix_nagaand 8y ago

Obfuscating the data would be no more difficult than obfuscating tor traffic by delaying, stuffing, and merging packets. Has anyone done a long term packet analysis of an echo, home, iPhone, pixel, or galaxy?

comex 8y ago

As far as I know, the hotwords are static because the detector uses a neural network pretrained specifically for those words. Training a new network for a custom hotword would require way too much training data. While it would be possible to instead use a generic network that decodes any type of speech – like it does when in full speech-to-text mode – and then use the outputted representation to compare to a custom hotword, that would be far more compute and power intensive, whereas the specialized network is relatively small. (The specialized network is also probably more accurate.) At least on battery-powered devices, more power usage for something that‘s always running is a dealbreaker. The same pressure doesn’t necessarily apply to home devices that are always plugged in, but all of the major in-home voice assistants also run on phones, and the providers probably prioritize a uniform user experience across devices. Disclaimer: I could be completely wrong, and/or the situation could change over time due to improved hardware and software. There was a rumor earlier this year that the Google Assistant might add custom hotword support in the future: https://9to5google.com/2018/01/29/google-app-7-20-assistant-apk-insight-teardown/ https://9to5google.com/2018/01/29/google-app-7-20-assistant-... Main source: Apple’s article about “Hey Siri”: https://machinelearning.apple.com/2017/10/01/hey-siri.html https://machinelearning.apple.com/2017/10/01/hey-siri.html