Differences between Work Factor and Time Complexity I am interested to know if work factor means the same thing as time complexity.

Quoting Work Factor : Uncovering keys in cryptosystems


  The Work Factor of a cryptosystem is related to its key-length and the
  working mechanism used (encryption and decryption algorithms). For
  example, if the brute force attack method is used to break the system
  (trying all possible combinations of the key), then the work factor is
  directly proportional to the length of the key.


This sounds awfully similar to what time complexity means to me. I hope to find out if the terminologies are similar.
Work factor is a more appropriate description because time factor is relative to processing power. Time factor, time complexity, computational complexity, and work factor, are used to describe the same thing. When someone says time complexity, they are probably not talking about actual time, but rather computation.

Work factor would be something like "200 trillion iterations of the block cipher", which is constant.

Time factor would be something like "20 years", but if you double the compute power, that is now 10 years. Therefore, time factor is only a good comparison with a fixed level of compute or when you can accurately estimate the amount of computation over a given length of time. Time is easier to explain to someone, and compute power raises at a fairly consistent rate, so using time is acceptable, and thus you can give an expiration date to things like public keys.

That being said, "time complexity" is probably the more common term used to describe computational complexity.