Cognitive password Cognitive password A cognitive password is a form of knowledge-based authentication that requires a user to answer a question, presumably something they intrinsically know, to verify their identity. Cognitive password systems have been researched for many years and are currently commonly used as a form of secondary access. They were developed to overcome the common memorability vs. strength problem that exists with the traditional password. Cognitive passwords, when compared to other password systems, can be measured through the usage of a memorability vs. guessability ratio. Research on passwords as an authentication method has struggled between memorability and strong security. Passwords
Most recent common ancestor all of the modern population. Due to pedigree collapse, modern individuals may still exhibit clustering, due to vastly different contributions from each of ancestral population . Most recent common ancestor In biology and genealogy, the most recent common ancestor (MRCA, also last common ancestor (LCA), or concestor) of any set of organisms is the most recent individual from which all the organisms are directly descended. The term is also used in reference to the ancestry of groups of genes (haplotypes) rather than organisms. The MRCA of a set of individuals can sometimes be determined by referring to an established pedigree.