Markdown Version | Session Recording

Session Date/Time: 23 Jul 2024 20:00

6man

Summary

The 6man session covered several important topics, including updates on source address selection, snack router flag signaling, DHCP prefix delegation availability, deprecation of the router alert option, and zone identifiers. There was also a discussion about a potential update to the IPv6 node requirements RFC. Several action items were identified, and further discussion is expected on the mailing list.

Key Discussion Points

• Source Address Selection Update (RFC 6724):
  • Discussion focused on heuristics for maintaining known local ULA prefixes.
  • Questions arose regarding treating FC00/8 differently from FD00/8, preferring ULAs over IPv4, and supporting off-link known local preferences.
  • Concerns about complexity of the algorithm for address selection.
• Snack Router RA Flag:
  • The draft defines a flag to identify self-configuring routers joining stub networks.
  • Request for early allocation of the flag due to deployed implementations.
  • Discussion on interactions with RA-guard and behavior when a router transitions between snack and infrastructure roles.
• DHCP Prefix Delegation Availability to Clients (P-flag):
  • The goal is to signal network support for the PD per-device addressing model.
  • Discussion on whether arbitrary prefix lengths should be allowed and signaling other PD use cases (e.g., tethering).
  • Concern raised regarding the necessity of this P-Flag and the implications it has to the way IPv6 extensions can be done in the future.
• Deprecation of Router Alert Option:
  • Proposal to deprecate the IPv6 router alert option, disallowing its use in future protocols.
  • Alternatives for RSVP-TE and MLD were presented.
  • Concerns raised about potential impacts on multicast snooping switches and legacy silicon.
• Zone Identifiers:
  • Discussion on the user interface for entering link-local addresses with zone identifiers.
  • Compromised text added, stating that the recommendations and normative statement in this document do not apply to web browsers
  • Discussion if this document is necessary to create.
• IPv6 Node Requirements (RFC 8504) Update:
  • Discussion of a potential update to RFC 8504 to reflect recent RFCs and drafts.
  • Suggestions for additions included Pref6, C-LOT, V6-Only considerations and potentially the inclusion of the DHC408 option.
  • Discussion of potential areas to be removed such as Mobile IPv6 and SEND.
• ICMPv6 Loopback:
  • Presentation of two similar drafts to ICMPv6 loopback, and discussion for an eventual merge

Decisions and Action Items

• Source Address Selection Update (RFC 6724):
  • Authors to consider treating all ULAs the same (FC00/7) for the heuristics.
  • Authors to clarify whether it "should" or "must" be for adding prefixes from RIO/PIOs.
• Snack Router RA Flag:
  • Authors to add text clarifying when the snack router bit should be set to zero (i.e., when the device is not intended to read the snack specification).
  • Authors to clarify interactions with RA guard in documentation.
• DHCP Prefix Delegation Availability to Clients (P-flag):
  • Authors to add write something about DHCP state machine to avoid trying to get new addresses if there are no addresses available.
  • Chairs to decide how to progress or address Mulli corner cases.
• Deprecation of Router Alert Option:
  • Authors to consult with silicon vendors about potential extensibility impacts.
• Zone Identifiers:
  • Authors to push this document to well-known web personalities.
• IPv6 Node Requirements (RFC 8504) Update:
  • Authors to proceed with the RFC update.
  • Authors to add a section related to IPv4 as a service and related transition technologies.
  • Authors to be careful with text on Segment Routing, not wanting it to apply it to every node.
• ICMPv6 Loopback:
  • Authors of the two ICMP Loopback drafts to merge their proposals into a single draft.

Next Steps

• Continue discussions on the mailing list for open questions on RFC 6724 update, snack router flag, DHCP prefix delegation availability, and deprecation of the router alert option.
• Chairs to work to get an issue tracker to address the raised questions around DHCP prefix delegation availability.
• Authors to work on revisions of the drafts incorporating feedback from the meeting.