EXTRA session minutes - IETF104 Prague - Monday Mar-25-2019 13:50 === Welcome Barry as new area director for the EXTRA working group. CHAT OVER IMAP: * A chat client, but using email underneath * proposed "submission token" spec can be used for any email flow, not just COI * can always fall back to "slow path", this is an upgrade to faster mail flow where there's an existing relationship/conversation happening between the parties. * Dovecot / OpenExchange have been playing with this for a while internally - looking for input from this group. Discussion of details: * different trust levels: temp/perm - does that make sense? Or just always refresh? * does the token come with a submission server name? Not right now, use MX or SRV. Maybe token should include submisison server hostname. * discussion of using token to say "prioritise this message" but keep the flow in band: problem, if everything is special, nothing is special, and every hop needs to honour this. Still not as fast as direct injection. * should this use HTTP POST rather than SMTP at all? Pros and cons. * lots of baggage comes with using email as the transport, but maybe that frame cost is OK so long as latency is low. * discussion of "using offsite mail filtering" as a common cause of a latency path that this could bypass. * standards-track "delivery-by", if not delivered by a certain time, drop it. Kind of the opposite of what we want here though. Dicussion of barriers to adoption: * many sites won't want to allow direct SMTP injection that bypasses their corporate firewall. Though if you're running a Jabber server, that does much the same thing! * Pro of SMTP vs HTTP post, just connect to a different server with different creds but inject same existing message via same SMTP protocol - less special case for client. Discussions of where the work could happen: * During the IETF fax working group there was a proposed SMTP immediate delivery mechanism. * Way back in 821 there was an SMTP command for exactly this mechanism * It couldn't happen in EXTRA - this would have to be an SMTP working group. RECHARTER: * This group was originally chartered without SMTP to avoid distraction and due to pushback about starting that work. * If we did SMTP, we'd also redo message format (RFC532[12] and MIME) and move them to internet standards. * ACTION: Bron to write an updated charter for EXTRA, continuing with our existing maintenance work. * ACTION: Alexey/Barry to write a charter for an SMTP/MIME working group. QUOTA: * Last time we met there was interest in a quota extension * Alexey and Dave Cridland already have an old draft * Call for co-author, Michael is interested in co-editing * Discussion of making setquota optional. * Discussion of "storage used" vs RFC822 sizes. Decided to mirror the language in RFC8438 STATUS=SIZE: > [...] it MUST be equal to or greater > than the sum of the values of the RFC822.SIZE FETCH message data > item [IMAP4rev1] of all messages in the mailbox. * ACTION: Bron to issue call for adoption EXTRA session minutes - IETF104 Prague - Tuesday Mar-26-2019 09:00 === IMAP4rev2: * BINARY - agreed that it should be leaf nodes only * SEARCHRES - include * MUST sent BYE - much discussion - e.g. TLS issues, can't even get a BYE down the wire. - conclusion: remove the MUST * Mailbox naming: Barry will look over the whole section - landmines for V1/V2 implementations - Chris has implemented, subtle issues around bare '&'. - Server needs to track if client has enabled imap4rev2 or smtputf8. * AUTHENTICATE - take out DIGEST-MD5 and suggest SCRAM-SHA-256. - But don't make it mandatory. - Suspect pushback from SEC ADs about not making it mandatory. * LIST reference argument - leave it as it is - explain why it's there and don't use it unless you have a strong use case - tell clients to use "" * LSUB - remove * Drop CHECK * SEARCH: - know at least 4 servers which implement it differently, nobody seems to mind - document should advise substring as a sensible default if you don't have an engine that does something else. - Barry will look at this. * Auto \Seen - don't change anything, but advise use of .PEEK * UID EXPUNGE will be fixed * RFC822 vs BODY[] - properly DEPRECATE. Advise use of other forms, but don't remove in this spec. * CAPABILITY - mention it can be sent in auth responses * NAMESPACE response -> add some text * Make sure SEARCH TEXT and SEARCH BODY differences are clarified ACTIONS: * Barry to look at Mailbox Naming * Barry to look at language for SEARCH * Alexey to look at capability and namespace text * NEXT STEPS: hope WGLC soon Milestones: * IMAP4rev2 -> June 2019