5 ms·

In the TETRA specification they use the term “key stream” to mean the output of a stream cipher, which they call a “key stream generator”. They aren’t XORing di

by fanf2 5y ago

In the TETRA specification they use the term “key stream” to mean the output of a stream cipher, which they call a “key stream generator”. They aren’t XORing directly with a large key - the TETRA key size is 80 bits. See section 6.3.2.2 of https://www.etsi.org/deliver/etsi_en/300300_300399/30039207/02.01.01_60/en_30039207v020101p.pdf https://www.etsi.org/deliver/etsi_en/300300_300399/30039207/...

chrisseaton 5y ago
Yes you can programatically generate a key.
- marcan_42 5y ago
  And we call that a stream cipher, not "XOR encryption", even though it uses a XOR operation. You're programmatically generating a keystream, which is not the same thing as a key.
  - ncmncm 5y ago
    See, this is why we can't have secure things.