{
  "slug": "medium-auxiliary-memory",
  "term": "Medium Auxiliary Memory",
  "aliases": [
    "MAM"
  ],
  "definition": "Medium Auxiliary Memory is nonvolatile storage associated with an individual storage medium, used to hold auxiliary attributes about the medium and its recorded data.",
  "note": "LTFS uses MAM attributes for identification and consistency checks, including index generation and location. This is separate from the on-tape XML index; inaccessible or stale MAM does not inherently prevent reading the volume. [c1] IBM exposes attributes for the formatting application and cartridge barcode, illustrating the distinction between cartridge metadata and stored file contents. [c2]",
  "status": "shipping",
  "advantages": [
    {
      "text": "Coherency metadata can avoid seeking to both partition ends during consistency checks.",
      "citationIds": [
        "c1"
      ]
    }
  ],
  "limitations": [
    {
      "text": "If a partition's stored Volume Change Reference is stale, MAM coherency attributes alone cannot establish volume consistency; the on-tape indexes must be checked.",
      "citationIds": [
        "c1"
      ]
    }
  ],
  "related": [
    "ltfs",
    "ltfs-index",
    "lto",
    "tape"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-15",
  "citations": [
    {
      "id": "c1",
      "title": "SNIA LTFS Format Specification 2.5.1, sections 4.1.21 and 10",
      "url": "https://www.snia.org/sites/default/files/technical-work/ltfs/release/SNIA-LTFS-Format-2-5-1-Standard.pdf",
      "accessed": "2026-10-15"
    },
    {
      "id": "c2",
      "title": "IBM Storage Archive SDE: Virtual extended attributes, volume metadata",
      "url": "https://www.ibm.com/docs/en/storage-archive-sde/2.4.8?topic=attributes-virtual-extended",
      "accessed": "2026-10-15"
    }
  ]
}