{
  "draft": "draft-ietf-ipsecme-ikev2-rename-esn-05",
  "doc_id": "RFC9827",
  "title": "Renaming the Extended Sequence Numbers (ESN) Transform Type in the Internet Key Exchange Protocol Version 2 (IKEv2)",
  "authors": [
    "V. Smyslov"
  ],
  "format": [
    "XML",
    "TEXT",
    "HTML",
    "PDF"
  ],
  "page_count": "8",
  "pub_status": "PROPOSED STANDARD",
  "status": "PROPOSED STANDARD",
  "source": "IP Security Maintenance and Extensions",
  "abstract": "This document clarifies and extends the meaning of Transform Type 5 in Internet Key Exchange Protocol Version 2 (IKEv2).  It updates RFC 7296 by renaming Transform Type 5 from \"Extended Sequence Numbers (ESN)\" to \"Sequence Numbers (SN)\".  It also renames two currently defined values for this Transform Type: value 0 from \"No Extended Sequence Numbers\" to \"32-bit Sequential Numbers\" and value 1 from \"Extended Sequence Numbers\" to \"Partially Transmitted 64-bit Sequential Numbers\".",
  "pub_date": "November 2025",
  "keywords": [
    "replay protection",
    "anti-replay",
    "IPsec",
    "ESP",
    "AH"
  ],
  "obsoletes": [],
  "obsoleted_by": [],
  "updates": [
    "RFC7296"
  ],
  "updated_by": [],
  "see_also": [],
  "doi": "10.17487/RFC9827",
  "errata_url": null
}