No known digital device or storage medium is invulnerable to decay and obsolescence. A foundational digital preservation capability is ensuring the readability of the bitstreams underlying the electronic records. ISO 14721 specifies that a trustworthy digital repository’s storage devices and storage media should be monitored and renewed (“refreshed”) periodically to ensure that the bit streams remain readable over time. A projected life expectancy of removable storage media does not necessarily apply in a specific instance of storage media.
Hence, it is important that a trustworthy digital repository have a protocol for continuously monitoring removable storage media (e.g., magnetic tape, external tape drives, or other media) to identify any that face imminent catastrophic loss. Ideally, this renewal protocol would automatically execute renewal by the digital repository.