Deprecating IPv6 Extension Headers on the Internet#

Tom Herbert (individual)

• Why: Measurement shows packets carrying IPv6 extension headers are discarded at high rates across the public Internet, EHs enable DoS amplification and carry known vulnerabilities, and the loss rates deter anyone from deploying new EHs at all. For anyone operating both a limited domain (DC) and Internet-facing paths, this decides whether EH-based mechanisms (e.g., SRH) are ever viable outside the domain.
• What: Recommends deprecating all IPv6 extension headers on the public Internet except ESP: relegate them to limited domains and discard EH-carrying packets at domain boundary routers — essentially formalizing what operators already do (from abstract only).
• How: A recommendations document changing expectations about EH handling at domain boundaries rather than a wire-format change; motivated by discard-rate data, DoS vectors, and the chilling effect on new EH development.
• Where applicable: Internet-facing IPv6 globally; the carve-out for limited domains is what keeps SRv6/segment-routing DC fabrics unaffected. Note maturity carefully: this is an individual draft that was never adopted by 6man and has expired on the datatracker — treat it as a provocative position statement shaping the EH debate, not emerging consensus.