As time proceeds computers become more powerful and the knowledge gained by crackers increases. This means that the developers of security methods have to strengthen the technologies that are used to guard against intrusion. The cost of cracking adjustment is a term used to describe the number of bits that need to be added to a key for an algorithm used in cryptography in order to keep it as secure as it was in the previous year of its existence. A general principle of cracking a key is that the larger the keyspace the more difficult it is to crack the encryption method based on it. Sometimes the term is abbreviated to COCA.