A demarc extension is the process of connecting your organizationâs network to a data lineâsuch as a T1, DSL, or POTSâprovided by the telephone company or another vendor.
Legacy system. In computing, a legacy system is an old method, technology, computer system, or application program, of, relating to, or being a previous or outdated computer system.. Often a pejorative term, referencing a system as legacy means that it paved the way for the standards that would follow it.
The first use of the term legacy to describe computer systems probably occurred in the 1970s. By the 1980s it was commonly used to refer to existing computer systems to distinguish them from the design and implementation of new systems.