I have joked before about the apparent lack of life in the universe, that we are just living in unencrypted 'plain text' mode. But all the developed aliens have moved to encrypted space. ;)
The AI stuff in the book is also really interesting.
Also, let's not forget that Vinge coined the term singularity.
Meanwhile the usual standard for encryption is "indistinguishable from random"... which kinda just doesn't make sense at the physical level. I'd be very interested to know if anyone has figured out how to do physical encoding/encryption that's indistinguishable from physical noise.
https://www.mit.edu/people/dpolicar/writing/prose/text/think...