Markdown Version | Session Recording

Session Date/Time: 28 Jun 2023 14:00

CBOR

Summary

The CBOR Working Group held a pre-IETF 117 meeting to discuss the status of active documents and finalize the agenda for the upcoming IETF 117 session. Key topics included the progression of the Time Tag document to Standards Track, the need for further simplification and a new Working Group Last Call for PACT, the status of CDDL 2.0 documents, and a discussion regarding the design principles for CBOR tags acting as "stand-ins" for other values.

Key Discussion Points

• Time Tag (Standards Track)

  • The previous discussions with Karsten had resolved outstanding issues, and Karsten posted final updates to the document.
  • It was confirmed that the document would be submitted to the IESG as Standards Track, rather than Informational.
  • A brief, one-week Working Group Last Call (WG LC) will be initiated to allow participants to review the latest changes and the status change.

• CBOR Packed (PACT)

  • The document remains pending due to a lack of implementation feedback, creating a "vicious cycle" where implementers wait for stability and stability waits for implementations.
  • Further simplification of the table setup, specifically for parallel setup of shared and argument tables, is planned to make it easier for basic packers to implement.
  • Karsten intends to have updated text and an implementation (using the cbor-packed gem) ready before the IETF 117 cut-off.
  • Due to significant changes since the last WG LC, the document is a strong candidate for another Working Group Last Call after the next version is submitted.

• CDDL 2.0 Documents

  • The various CDDL 2.0-related documents are now official Working Group documents.
  • Karsten plans to first submit a document with errata and corrections very soon.
  • The module structure and control operators documents will follow, likely benefiting from further discussion at IETF 117.
  • It was noted that some implemented CDDL 2.0 features, such as degenerate sizes and "flattening," are useful for implementations but may not require formal standardization as their function is clear.

• IETF 117 Agenda Review

  • The proposed agenda for IETF 117 by Christian was reviewed and largely accepted.
  • Time Tag will remain on the agenda for a brief status update, but no detailed discussion is expected.
  • Key discussion items for IETF 117 include CBOR literals (e.g., EDN literals), CDDL 2.0 documents, DNS CBOR, and DCBOR.
  • Karsten expects to have the grammar for CBOR literals, translated into ABNF, ready before the IETF 117 cut-off.

• PACT "Stand-in" Mechanism and Design Principles

  • A participant raised a discussion about CBOR tags "standing in" for other concrete values (with PACT being a prime example).
  • There was a recap of previous discussions indicating a desire to move slightly beyond purely syntactic validity while carefully avoiding excessive semantic complexity that could lead to interoperability issues or "forking" of the CBOR ecosystem.
  • It was agreed that this design principle should be formally captured.

Decisions and Action Items

• Time Tag:

  • Decision: Submit to IESG as a Standards Track document.
  • Action: WG Chair (Marco) to initiate a one-week Working Group Last Call for the latest changes and status change. (Marco)
  • Action: WG Chair (Marco) to process the document and send to the IESG after the WG LC concludes. (Marco)

• CBOR Packed (PACT):

  • Action: Karsten to prepare an updated document version with simplified table setup, aiming for submission before the IETF 117 cut-off. (Karsten)
  • Action: Karsten to inform the WG Chair when the next version is ready for a new Working Group Last Call. (Karsten)

• CDDL 2.0:

  • Action: Karsten to submit an updated document addressing errata and corrections soon. (Karsten)

• CBOR Literals:

  • Action: Karsten to prepare the grammar for CBOR literals, including ABNF translation, before the IETF 117 cut-off. (Karsten)

• PACT "Stand-in" Mechanism:

  • Decision: An informational document will be created to serve as a "memo to future selves" regarding the design principles for CBOR tags acting as "stand-ins" for other values, balancing syntactic and semantic validity to preserve interoperability.
  • Action: Karsten to draft this informational document. (Karsten)

Next Steps

• The WG Chair will initiate the one-week WG LC for Time Tag.
• Karsten will continue work on the PACT, CDDL 2.0, and CBOR Literals documents, aiming for updates before IETF 117.
• Further discussions on CDDL 2.0 features will take place at IETF 117.
• Karsten will begin drafting the informational document on CBOR tag "stand-in" design principles.
• The Working Group will convene for its scheduled session at IETF 117 in San Francisco.