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4. IANA Considerations

4.1. SMTP Service Extensions Registry​

IANA has added a new value "SMTPUTF8" to the "SMTP Service Extension" registry of the "Mail Parameters" registry, according to the following data:

KeywordsDescriptionReference
SMTPUTF8Internationalized email address[RFC6531]

4.2. SMTP Enhanced Status Code Registry​

The code definitions in this document replace those specified in RFC 5336, following the guidance in Sections 3.5 and 3.7.4.2 of this document, and based on RFC 5248 [RFC5248]. IANA has updated the "Simple Mail Transfer Protocol (SMTP) Enhanced Status Code Registry" with the following data:

Code: X.6.7 Sample Text: Non-ASCII addresses not permitted for that sender/recipient Associated basic status code: 550, 553 Description: This indicates the reception of a MAIL or RCPT command that non-ASCII addresses are not permitted. Defined: RFC 6531 (Standards Track) Submitter: Jiankang YAO Change controller: [email protected]

Code: X.6.8 Sample Text: UTF-8 string reply is required, but not permitted by the SMTP client Associated basic status code: 252, 550, 553 Description: This indicates that a reply containing a UTF-8 string is required to show the mailbox name, but that form of response is not permitted by the SMTP client. Defined: RFC 6531 (Standards Track) Submitter: Jiankang YAO Change controller: [email protected]

Code: X.6.9 Sample Text: UTF-8 header message cannot be transferred to one or more recipients, so the message must be rejected Associated basic status code: 550 Description: This indicates that transaction failed after the final "." of the DATA command. Defined: RFC 6531 (Standards Track) Submitter: Jiankang YAO Change controller: [email protected]

Code: X.6.10 Description: This is a duplicate of X.6.8 and is thus deprecated.

4.3. WITH Protocol Types Sub-Registry of the Mail Transmission Types Registry​

IANA has modified or added the following entries in the "WITH protocol types" sub-registry under the "Mail Transmission Types" registry.

WITH protocol typesDescriptionReference
UTF8SMTPESMTP with SMTPUTF8[RFC6531]
UTF8SMTPAESMTP with SMTPUTF8 and AUTH[RFC4954] [RFC6531]
UTF8SMTPSESMTP with SMTPUTF8 and STARTTLS[RFC3207] [RFC6531]
UTF8SMTPSAESMTP with SMTPUTF8 and both STARTTLS and AUTH[RFC3207] [RFC4954] [RFC6531]
UTF8LMTPLMTP with SMTPUTF8[RFC6531]
UTF8LMTPALMTP with SMTPUTF8 and AUTH[RFC4954] [RFC6531]
UTF8LMTPSLMTP with SMTPUTF8 and STARTTLS[RFC3207] [RFC6531]
UTF8LMTPSALMTP with SMTPUTF8 and both STARTTLS and AUTH[RFC3207] [RFC4954] [RFC6531]