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A comment on RTL-entropy: Uses RTL-SDR to turn a DVB-T dongle into an entropy source. Parent comment

Re:RTL-entropy: Uses RTL-SDR to turn a DVB-T dongle into an ... by adrianN on Wednesday March 28, 2018 @08:15AM (#16697077)
I don't think this is true without some assumptions. The two bitstreams could cancel out if cleverly chosen.
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Re:RTL-entropy: Uses RTL-SDR to turn a DVB-T dongle into an ... by simias on Wednesday March 28, 2018 @08:20AM (#16697111)
That would mean that the attacker can already predict /dev/urandom, rendering it effectively useless. So the parent is right, "the result will be as strong as the best source of entropy", if both sources are bad then the result will be as well.
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Re:RTL-entropy: Uses RTL-SDR to turn a DVB-T dongle into an ... by jonathanstrange on Wednesday March 28, 2018 @08:52AM (#16697283)
It is true under the assumption that the two sources are independent of each other. If one of the sources is entirely known or predictable, this will not affect the entropy of the other source.
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Re:RTL-entropy: Uses RTL-SDR to turn a DVB-T dongle into an ... by Tomte on Wednesday March 28, 2018 @08:19AM (#16697104)
If you know "the other" bitstream, sure. The only sensible premise is that you don't.
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Re:RTL-entropy: Uses RTL-SDR to turn a DVB-T dongle into an ... by dTal on Wednesday March 28, 2018 @08:51AM (#16697280)
If both bitstreams are cleverly chosen, then neither is a source of entropy.
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