It'd be interesting to know the length of a sequence that will never be sent over the Internet. In B. Schneier's "Applied Cryptography" there is a discussion of 256-bit numbers, the minimal amount of energy and mass required to guess them and conclusion that "brute-force attacks against 256-bit keys will be infeasible until computers are built from something other than matter and occupy something other than space."
The length of a never-transmitted-on-the-internet sequence is probably much shorter than 256 bits, even 128 bits (as the article mentions).
The length of a never-transmitted-on-the-internet sequence is probably much shorter than 256 bits, even 128 bits (as the article mentions).
More details here:
https://security.stackexchange.com/a/25392