Session Date/Time: 10 Nov 2021 12:00

emailcore

Summary

The emailcore working group session primarily focused on advancing 5322bis and 5321bis documents towards Working Group Last Call (WGLC). Key discussions revolved around the handling of source routes (ticket 5321), clarification of quoted strings (tickets 21, 49), updates to the abstract and references to other protocols/documents, and the scope of the forthcoming Applicability Statement. The group made several decisions on how to modify the 5321bis text and agreed to schedule an interim meeting in December to continue progress.

Key Discussion Points

RFC 5322bis Status Update: Pete reported that 5322bis has a minor text fix and an optional field reinstated. Editor's notes need to be cleaned, and the document is considered ready for Working Group Last Call (WGLC) pending any new issues.
Ticket 5321: Source Routes Clarification
- The mailing list consensus leaned towards "Option A": stripping all mentions of source route handling in text and ABNF, except for a historical note pointing to RFC 821 for backward compatibility.
- Discussion on parsing vs. generation: Elliott expressed a preference for "must not be generated, may be parsed" to support historical mailboxes. John clarified that 5321bis (SMTP command stream) differs from 5322bis (message parsing), but noted that 5322 does discuss parsing old mailboxes.
- Editor's approach: John (editor) proposed drafting the historical paragraph in 5321bis-06 for review.
- Multiple slides were presented identifying specific sections and sentences in 5321bis that reference source routing, which will need to be removed or rephrased according to Option A.
Tickets 21 & 49: Quoted Strings in Email Comparison
- Local part equivalence: A suggestion to add examples of lexically equivalent local parts (e.g., quote "foo" [email protected] vs [email protected]).
- Terminology: John suggested using "lexical equivalence" over "semantic equivalence" to avoid entanglement with Unicode canonicalization issues.
- Text flow: A proposal to move the explanation of the backslash character and its usage before its first example appears in the text for better readability.
Abstract Update (Ticket Not Specified)
- Proposed to replace specific text about "mail submission protocol" in the abstract with a more general sentence: "The document also provides information about use of SMTP for other than strict mail transport and delivery." This aims to be concise and avoid getting bogged down in specific submission details.
Ticket 53: Informative References to MIME and/or Message Submission
- Goal: Minimize and generalize references to the Applicability Statement (AS) in 5321bis.
- Decision: 5321bis should not mention MIME at all, possibly deferring to 5322bis or the forthcoming AS.
- Proposed vague phrasing for AS reference: "other relevant documents and their relationships are discussed in the forthcoming applicability statement."
Applicability Statement Compliance (MUST/SHOULD for Extensions)
- Discussion: Whether 5321bis should specify MUST/SHOULD requirements for SMTP extensions (8-bit MIME, enhanced reply codes, DSNs, pipelining, SMT UTF-8) or if this should reside solely in the AS.
- Consensus: Defer detailed discussion of these compliance levels to the AS itself, rather than including them in 5321bis.
- The proposed tentative compliance levels (8-bit MIME, enhanced reply codes, DSNs as MUST; pipelining, SMT UTF-8 as SHOULD) were noted for future AS discussions.
Ticket 52: Forwarding vs. Redistribution
- A cut-and-paste error was identified in section 3.9.2, where "forwarding" should be "redistribution" to align with earlier text about mail list operations. This correction is already in 5321bis-06.
Ticket 54: Hop-by-Hop Authentication or Encryption
- Proposal: Address these topics in the forthcoming Applicability Statement.
- Initial text on these topics is expected to be available for discussion at a potential December interim meeting.
Large Files Emailing Problem (Informational)
- Ron provided an update on the need to address large file emailing, which is currently handled by proprietary URL solutions. This might involve a future working group and require defining storage, authentication, and transport aspects beyond just MIME format (e.g., external-body). John Levine mentioned existing MIME mechanisms (like external-body) could be made more robust with checksums and dates.

Decisions and Action Items

Decision: RFC 5322bis is largely ready for Working Group Last Call (WGLC), pending minor editor clean-up.
Decision: For Ticket 5321 (Source Routes), 5321bis will be stripped of all mentioning of handling source routes in text and ABNF, except for a historical note referencing RFC 821 for backward compatibility.
- Action Item: John (editor) will draft the historical note and implement the removals in the next 5321bis revision.
Decision: For Tickets 21 & 49 (Quoted Strings), examples of lexical equivalence for local parts will be added, and the explanation of the backslash character will be reordered.
- Action Item: John (editor) to implement these changes.
Decision: The abstract of 5321bis will be updated with more general phrasing regarding submission protocols.
- Action Item: John (editor) to implement this change.
Decision: References to MIME and message submission in 5321bis will be minimized and made vague, pointing to the forthcoming Applicability Statement.
- Action Item: John (editor) to implement this change.
Decision: The word "forwarding" in section 3.9.2 of 5321bis will be changed to "redistribution" (already done in -06).
Decision: Discussions on hop-by-hop authentication and encryption (Ticket 54) will be deferred to the Applicability Statement.
Action Item: Co-chairs to announce and schedule an interim meeting in early December (week of Dec 6-10 suggested).
Action Item: Pete (editor) to prepare 5322bis for WGLC soon.
Action Item: John (editor) expects to release the next version of 5321bis before the end of November to support the December interim.

Next Steps

Issue 5322bis for Working Group Last Call.
Co-chairs to finalize scheduling and announce an interim meeting for early December.
Editor to release 5321bis-06 (or next version) by end of November, incorporating decisions made.
Continue work on the Applicability Statement, with initial text on hop-by-hop authentication/encryption and compliance MUST/SHOULD requirements for the December interim.