Automated storage tiering (AST) is a storage software management feature that dynamically moves information between different disk types and RAID levels to meet space, performance and cost requirements.
Data migration is the process of transferring data between data storage systems, data formats or computer systems.
Information life cycle management (ILM) is a comprehensive approach to managing the flow of an information system's data and associated metadata from creation and initial storage to the time when it becomes obsolete and is deleted.
Secondary storage is used to protect inactive data written from a primary storage array to a nonvolatile tier of disk, flash or tape.
Tier 1 storage is a reference to the higher performing systems in a tiered storage environment.
Tiered data storage moves data to various types of storage media -- based on performance requirements, protection level and frequency of use -- to reduce storage costs.