6MAN Working Group - IETF 125 Shenzhen

Wednesday, 18 March 2026, 14:00-16:00 (UTC+8)

Room: Shangri La Ballroom 1
Chairs: Bob Hinden, Jen Linkova
Minute taker: EKR AI Tool, edited by w.g. chairs
Jabber Scribe: N/A

Jabber Room: 6man@jabber.ietf.org

Meetecho (Full Client):
https://meetings.conf.meetecho.com/ietf125/?session=35086

Meetecho (Onsite Tool):
https://meetings.conf.meetecho.com/onsite125/?session=35086

Agenda Wednesday, 18 March 2026, 14:00-16:00 (UTC+8)

• Introduction, Agenda Review, and Document Status , Chairs, 10 min.

Working Group Drafts

• YANG Data Model for IPv6 Neighbor Discovery,
  draft-ietf-6man-ipv6-neighbor-discovery-yang , Fan Zhang, 10 min
• IPv6 Query for Enabled In-situ OAM Capabilities,
  draft-ietf-6man-icmpv6-ioam-conf-state , Xiao Min, 10 min
• Carrying Network Resource (NR) related Information in IPv6 Extension
  Header, draft-ietf-6man-enhanced-vpn-vtn-id , Jie Dong, 10 min

• IPv6 Node Requirements, draft-ietf-6man-rfc8504-bis , Tim Winters,
  15 min
  ### Active Individual Drafts {#active-individual-drafts}

• The IPv6 Loopback Address Prefix, draft-kumari-ipv6-loopback ,
  Warren Kumari, Geoff Huston, 10 min.

• Deprecating IPv6 Extension Headers on the Internet,
  draft-herbert-deprecate-eh/ ,Deprecate IPv6 Destination Options
  Before the Routing Header, draft-herbert-deprecate-destops-before-rh
  ,Infight Removal of IPv6 Hop-by-Hop and Routing Headers,
  draft-herbert-eh-inflight-removal , Tom Herbert 15 min.
• Updates to DNS64 Functionality Advertisement for DNS RA Option,
  draft-ma-6man-ra-dns64-flag-01 , Chenhao Ma, 15 min.
• ICMP Error Handling for VPNs in SRv6 Networks,
  draft-varhal-6man-icmp-srv6-vpn , Balazs Varga, 15 min.

This is a summary of the 6man Working Group session held during IETF 125
in Shenzhen China. It was produced by the automated minute tool
(https://ietfminutes.org/about.html) written by Eric Rescorla
ekr@rtfm.com. It was edited by the chairs after the meeting.

Summary

The 6MAN Working Group met at IETF 125 in Shenzhen China. The session
was chaired by Jen Linkova and Bob Hinden (both participating remotely),
with Erik Vyncke acting as the on-site chair. The meeting marked a
leadership transition as Eric Kline stepped down as the responsible Area
Director (AD), with Erik Vyncke taking over the role. The agenda covered
four working group documents and five individual presentations, focusing
on neighbor discovery, extension header security, and routing-related
ICMP behavior.

Key Discussion Points

Introduction and Document Status

• AD Transition: Eric Kline is finishing his term; Erik Vyncke is
  the new responsible AD for 6MAN.
• MISREF Issues: Several drafts (including
  draft-ietf-6man-rfc6724-bis) are held in the RFC Editor Queue due
  to a normative reference to a SNAC draft. The ADs and chairs
  discussed potentially changing the SNAC reference to "informative"
  to unblock the queue. Draft will be sent back to w.g. to revise,
  then repeat w.g. last call and advance.
• draft-ietf-6man-slaac-renum: Lorenzo Colitti raised concerns
  that the current draft could cause battery drain on mobile devices
  by sending too many Router Advertisements (RAs) during renumbering.
  The draft will be returned to the working group for revision.
• draft-ietf-6man-sidlist-clarification, Erik Kline volunteered to
  be document shephard.

Working Group Drafts

• YANG Data Model for IPv6 Neighbor Discovery

  • Presenter: Fan Yang (on behalf of
    draft-ietf-6man-ipv6-neighbor-discovery-yang)
  • Discussion: Updates based on YANG Doctor reviews were
    presented, including the removal of certain dynamic resolution
    leaves and simplification of Proxy NA. The authors requested a
    Working Group Last Call (WGLC).
  • Action: Chairs to start a w.g. last call.

• IPv6 Query for Enabled In-situ OAM Capabilities

  • Presenter: Xiao Min (on behalf of
    draft-ietf-6man-icmpv6-ioam-conf-state)
  • Discussion: The draft’s foundation has moved from RFC 4620
    to draft-ietf-intarea-icmp-query. The working group will wait
    for the INTAREA draft to progress before initiating WGLC.

• Carrying Network Resource (NR) related Information in IPv6
  Extension Header

  • Presenter: Jie Dong (on behalf of
    draft-ietf-6man-enhanced-vpn-vtn-id)
  • Discussion: Debate occurred regarding the fixed 32-bit
    length of the NRP selector ID. Greg Mirsky and Erik Vyncke
    suggested that 6MAN should perhaps defer the length definition
    to other groups (like TEAS or MPLS), though the authors noted
    the current encoding is extensible.

• IPv6 Node Requirements

  • Presenter: Tim Chown (on behalf of
    draft-ietf-6man-rfc8504-bis)
  • Discussion: The authors plan to revert the Extension Header
    (EH) limit text to the original RFC 8504 language since the
    dedicated EH limits draft did not progress. Updates regarding
    PMTUD (RFC 8899) and DNS section clarifications were discussed.
  • Should be ready for w.g. last call prior to next IETF meeting.

Individual Presentations

• The IPv6 Loopback Address Prefix

  • Presenter: Jen Linkova (on behalf of authors)
  • Discussion: The proposal to expand the loopback prefix to
    ::/96 met significant resistance. Brian Carpenter and Jen
    Linkova expressed concerns about overlapping with the
    unspecified address (::). Lorenzo Colitti noted the utility of
    multiple loopback addresses but questioned the specific prefix
    choice.

• Addressing Extension Header Vulnerabilities

  • Presenter: Tom Herbert
  • Discussion: This covered four distinct ideas: enforcing EH
    ordering/occurrence, "obsoleting" certain EHs on the public
    internet, removing EHs at egress, and restricting Destination
    Options locations.
  • Feedback: Lorenzo Colitti noted that fragmentation cannot be
    deprecated because DNS relies on it. Ron Bonica supported
    enforcing ordering/occurrence rules as "MUSTs" but opposed
    middlebox modification/removal of headers. Comment that we need
    to be careful to not limit future flexability.

• Updates to DNS64 Functionality Advertisement for DNS RA
  Option

  • Presenter: Chenhao
  • Discussion: The proposal adds a "T" flag to RDNSS to
    indicate DNS64 capability. Jordi Palet and Lorenzo Colitti
    argued that existing tools (like separate APNs or
    ipv4only.arpa lookups) already solve the stated use cases
    without protocol changes.

• ICMP Error Handling for VPNs in SRv6 Networks

  • Presenter: Balaji Venkat Venkataswami
  • Discussion: The draft addresses how to return ICMP errors to
    VPN endpoints in an SRv6 network without requiring P-nodes to be
    VPN-aware. Suresh Krishnan suggested the work might better
    belong in the SPRING WG. Ron Bonica supported the technical
    approach of not involving the tunnel egress.

Decisions and Action Items

• draft-ietf-6man-slaac-renum: Will be returned to 6MAN. Authors
  must revise the draft to address battery consumption concerns
  (specifically the frequency/count of RAs sent during renumbering)
  before advancing.
• draft-ietf-6man-rfc8504-bis: Authors to update references
  (including RFC 8899) and finalize the revert of EH limit text to
  match RFC 8504.
• draft-ietf-6man-yang-data-model-for-ipv6-neighbor-discovery:
  Chairs will initiate WGLC following the meeting.
• SNAC MISREF: ADs (Erik Vyncke and Eric Kline) will investigate
  if the normative dependency on the SNAC draft can be downgraded to
  informative to unblock draft-ietf-6man-rfc6724-bis and the RA-Flag
  draft.

Next Steps

• Liaison Statement: David Schinazi and Suresh Krishnan will
  coordinate a liaison statement to the IEEE regarding
  draft-ietf-6man-ieee80211-fms.
• draft-ietf-6man-enhanced-vpn-vtn-id: Continued discussion on
  the mailing list regarding ID length flexibility.
• Individual Drafts: Authors of the Loopback and DNS64 RA drafts
  were encouraged to refine their problem statements and consult the
  V6OPS working group for operational consensus.
• SRv6 ICMP: Chairs from 6MAN and SPRING will discuss the
  appropriate home for this work.

Meeting adjourned