Enterprise wide migration activities always begin with performing a detailed portfolio assessment of multiple systems that exist in the organization. This triggers a product rationalization activity by which a detailed charter is prepared that provides the migration pathway for various systems in the organization.

As mentioned earlier, Input for a product rationalization activity is the detailed system portfolio document along with technology stack. On a high level, existing system can be categorized based on the criticality and their fit into enterprise wide road map. On the context of migration, classifications of systems are done as following types.

	Systems that need to continue as it is in existing form.(Type-1)
	Systems retaining the core engine. (Type-2)
	Systems for environment upgradation. (Type-3)
	Systems that need to be reengineered in the new technology stack. (Type-4)
	Systems turned obsolete. (Type-5)