A cryptographic hash function must be able to withstand all known types of cryptanalytic attack. In Germany, each cryptographic department was responsible for cryptanalytic operations. The DMCA has affected cryptography, because many fear that cryptanalytic research may violate the DMCA. The Black Chamber was the United States' first peacetime cryptanalytic organization. This attack is a special type of the general cryptanalytic time/memory tradeoff attack. This attack is a special type of the general cryptanalytic "time/memory tradeoff attack". However, none of the algorithms in current use are publicly known to have cryptanalytic weaknesses. It also influenced the academic development of cryptanalytic attacks. Organization appeared to be fluid, varying according to metrics like intelligence and cryptanalytic priorities. This was the height of Yardley's cryptanalytic career. Perfect secrecy is a strong notion of cryptanalytic difficulty. However, as the cryptanalytic work became increasingly mechanized, many more staff were needed. Many researchers feared that the NSA had chosen curves that gave them a cryptanalytic advantage.