Architecture-driven modernization

Architecture-driven modernization is the name of the initiative of the Object Management Group (see OMG ADM Task Force website) related to building and promoting standards that can be applied to modernize legacy systems. The objective of this initiative is to provide standard representations of views of existing systems in order to enable common modernization activities, such as code analysis and comprehension, and software transformation.
Knowledge Discovery Metamodel (KDM).
The foundation of the architecture-driven modernization initiative is the OMG specification Knowledge Discovery Metamodel (KDM).
Usually the knowledge obtained from existing software is presented in the form of models to which specific queries can be made when necessary. An entity relationship diagram is a frequent format of representing knowledge obtained from existing software. Knowledge Discovery Metamodel defines an ontology for the software assets and their relationships for the purpose of performing knowledge discovery of existing code. The KDM Analytics company maintains an open portal for the Knowledge Discovery Metamodel (see KDM Portal).
Relationship to MDA.
Existing (or "legacy") software has been one of biggest obstacles for applying model-driven architecture. The acronym for architecture-driven modernization (ADM) is coincidentally "MDA in reverse". MDA is the acronym for OMG's model-driven architecture, which purports the use of models and transformations to deliver new software. ADM is related to the concept of reverse engineering. Software modernization is "architecture-driven" when there is the need to capture and retool various architectural aspects of existing application environments. This modernization does not preclude source-to-source migrations (where appropriate), but encourages user organizations to consider modernization from an analysis and design based perspective. In doing so, project teams will ensure that obsolete concepts or designs are not propagated into modern languages and platforms. The bottom-line results deliver modernized systems that conform more effectively to current business practices and strategic requirements. 
Vendors.
Some of the vendors providing Architecture-Driven Modernization software tooling & methods: