This International Standard defines a meta-model for representing existing software assets, their associations, and operational environments, referred to as the Knowledge Discovery Meta-model (KDM). This is the first in the series of specifications related to Software Assurance (SwA) and Architecture-Driven Modernization (ADM) activities. KDM facilitates projects that involve existing software systems by insuring interoperability and exchange of data between tools provided by different vendors. One common characteristic of various tools that address SwA and ADM challenge is that they analyze existing software assets (for example, source code modules, database descriptions, build scripts, etc.) to obtain explicit knowledge. Each tool produces a portion of the knowledge about existing software assets. Such tool-specific knowledge may be implicit ("hard-coded" in the tool), restricted to a particular source language, and/or particular transformation, and/or operational environment. All the above may hinder interoperability between different tools. The meta-model for Knowledge Discovery provides a common repository structure that facilitates the exchange of data contained within individual tool models that represent existing software assets. The meta-model represents the physical and logical assets at various levels of abstraction. The primary purpose of this meta-model is to provide a common interchange format that will allow interoperability between existing modernization and software assurance tools, services, and their respective intermediate representations.