Tom7-skipstate generator constructions

Some contsructions based on the Tom7-skipstate device.

Self-skipping generator

This is a self-skipping generator: the output from the generator at each step is fed back into the skipstate input (so for every output bit of one, the next bit is skipped).

I am wary of these sorts of simple feedbacks. The generator's state has too simple a relation to the feedback, and I don't trust it. You know the next state will be skipped when the output is 1, which facilitates a known-plaintext attack. This seems highly insecure.

This is a mutual skipstate generator. Each generator controls the skip input of the other, and the output of the device is the the exclusive or of the two outputs.

I think this one is nicer; regardless of the output you can't tell exactly whether or not states were skipped and in which generator.

Since a skipstate generator is an inline generator, more complex generators can be formed using it. Check out the Tom7-inline-bridge device, for instance.

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