Generally, a genealogical DNA test might use either autosomal STRs or autosomal SNPs. (STR's are Short Tandem Repeats; SNPs are single-nucleotide polymorphisms.) However, testing companies do not currently offer autosomal STRs tests that use enough STR markers for genealogy.
The schema is the Active Directory component that defines all the objects and attributes that the directory service uses to store data. The physical structure of the schema consists of the object definitions. The schema itself is stored in the directory.
The diagram of the Active Directory architecture (Figure 2.3) illustrates four avenues of entry to Active Directory: LDAP/ADSI, REPL (replication), SAM, and MAPI. Each of these access routes uses a different set of protocols and APIs that enable communication with the directory service. Table 2.1 shows the APIs that Active Directory supports and that can be used by developers to integrate with Active Directory or use resources in Active Directory.