Network Working Group A. Melnikov Internet-Draft Isode Ltd Intended status: Informational G. Lunt Expires: August 29, 2013 A. Ross SMHS Ltd February 25, 2013 Military Message Handling System (MMHS) over SMTP draft-melnikov-mmhs-profile-03 Abstract A Military Message Handling System (MMHS) processes formal messages ensuring release, distribution, security, and timely delivery across national and international strategic and tactical networks. The MMHS Elements of Service are defined as a set of extensions to the ITU-T X.400 (1992) international standards and are specified in STANAG 4406 Edition 2 or ACP 123. This document specifies how a comparable messaging service can be provided using SMTP and its extensions. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on August 29, 2013. Copyright Notice Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect Melnikov, et al. Expires August 29, 2013 [Page 1] Internet-Draft MMHS over SMTP February 2013 to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Conventions Used in This Document . . . . . . . . . . . . . . 5 3. Elements of Service . . . . . . . . . . . . . . . . . . . . . 5 3.1. Profile Support . . . . . . . . . . . . . . . . . . . . . 6 3.2. Basic Elements of Service . . . . . . . . . . . . . . . . 8 3.2.1. Access Management . . . . . . . . . . . . . . . . . . 8 3.2.2. Content Type Indication . . . . . . . . . . . . . . . 8 3.2.3. Converted Indication . . . . . . . . . . . . . . . . . 9 3.2.4. Delivery Time Stamp Indication . . . . . . . . . . . . 9 3.2.5. MM Identification . . . . . . . . . . . . . . . . . . 9 3.2.6. Message Identification . . . . . . . . . . . . . . . . 9 3.2.7. Non-delivery Notification . . . . . . . . . . . . . . 9 3.2.8. Original Encoded Information Types . . . . . . . . . . 10 3.2.9. Submission Time Stamp Indication . . . . . . . . . . . 10 3.2.10. Typed Body . . . . . . . . . . . . . . . . . . . . . . 10 3.2.11. User/UA Capabilities Registration . . . . . . . . . . 10 3.3. Optional Elements of Service . . . . . . . . . . . . . . . 10 3.3.1. Alternate Recipient Allowed . . . . . . . . . . . . . 10 3.3.2. Alternate Recipient Allowed . . . . . . . . . . . . . 10 3.3.3. Alternate Recipient Assignment . . . . . . . . . . . . 10 3.3.4. Authorizing Users Indication . . . . . . . . . . . . . 10 3.3.5. Auto-forwarded Indication . . . . . . . . . . . . . . 10 3.3.6. Blind Copy Recipient Indication . . . . . . . . . . . 10 3.3.7. Body Part Encryption Indication . . . . . . . . . . . 10 3.3.8. Conversion Prohibited . . . . . . . . . . . . . . . . 10 3.3.9. Conversion Prohibition in Case of Loss of Information . . . . . . . . . . . . . . . . . . . . . 10 3.3.10. Cross Referencing Indication . . . . . . . . . . . . . 10 3.3.11. Deferred Delivery . . . . . . . . . . . . . . . . . . 10 3.3.12. Deferred Delivery Cancellation . . . . . . . . . . . . 10 3.3.13. Delivery Notification . . . . . . . . . . . . . . . . 10 3.3.14. Designation of Recipient by Directory Name . . . . . . 11 3.3.15. Disclosure of Other Recipients . . . . . . . . . . . . 11 3.3.16. DL Expansion History Indication . . . . . . . . . . . 11 3.3.17. DL Expansion Prohibited . . . . . . . . . . . . . . . 11 3.3.18. Expiry Date Indication . . . . . . . . . . . . . . . . 11 3.3.19. Explicit Conversion . . . . . . . . . . . . . . . . . 11 3.3.20. Forwarded MM Indication . . . . . . . . . . . . . . . 11 3.3.21. Grade of Delivery Selection . . . . . . . . . . . . . 11 3.3.22. Hold for Delivery . . . . . . . . . . . . . . . . . . 11 3.3.23. Incomplete Copy Indication . . . . . . . . . . . . . . 11 Melnikov, et al. Expires August 29, 2013 [Page 2] Internet-Draft MMHS over SMTP February 2013 3.3.24. Language Indication . . . . . . . . . . . . . . . . . 11 3.3.25. Latest Delivery Designation . . . . . . . . . . . . . 11 3.3.26. Multi-destination Delivery . . . . . . . . . . . . . . 11 3.3.27. Multi-part Body . . . . . . . . . . . . . . . . . . . 11 3.3.28. Non-receipt Notification Request Indication . . . . . 11 3.3.29. Obsoleting Indication . . . . . . . . . . . . . . . . 11 3.3.30. Originator Indication . . . . . . . . . . . . . . . . 11 3.3.31. Originator Requested Alternate Recipient . . . . . . . 11 3.3.32. Prevention of Non-delivery Notification . . . . . . . 11 3.3.33. Primary and Copy Recipients Indication . . . . . . . . 11 3.3.34. Receipt Notification Request Indication . . . . . . . 11 3.3.35. Redirection Disallowed by Originator . . . . . . . . . 11 3.3.36. Redirection of Incoming Messages . . . . . . . . . . . 11 3.3.37. Reply Request Indication . . . . . . . . . . . . . . . 11 3.3.38. Replying MM Indication . . . . . . . . . . . . . . . . 12 3.3.39. Requested Preferred Delivery Method . . . . . . . . . 12 3.3.40. Subject Indication . . . . . . . . . . . . . . . . . . 12 3.3.41. Use of Distribution List . . . . . . . . . . . . . . . 12 3.4. Military Elements of Service . . . . . . . . . . . . . . . 12 3.4.1. Primary Precedence . . . . . . . . . . . . . . . . . . 12 3.4.2. Copy Precedence . . . . . . . . . . . . . . . . . . . 12 3.4.3. Message Type . . . . . . . . . . . . . . . . . . . . . 12 3.4.4. Exempted Addresses . . . . . . . . . . . . . . . . . . 12 3.4.5. Extended Authorization Info . . . . . . . . . . . . . 12 3.4.6. Distribution Code . . . . . . . . . . . . . . . . . . 12 3.4.7. Message Instructions . . . . . . . . . . . . . . . . . 12 3.4.8. Clear Service . . . . . . . . . . . . . . . . . . . . 12 3.4.9. Other Recipient Indicator . . . . . . . . . . . . . . 12 3.4.10. Originator Reference . . . . . . . . . . . . . . . . . 12 3.4.11. Use of Address List . . . . . . . . . . . . . . . . . 12 3.5. Transition Elements of Service . . . . . . . . . . . . . . 12 3.5.1. Handling Instructions . . . . . . . . . . . . . . . . 12 3.5.2. Pilot Forwarded . . . . . . . . . . . . . . . . . . . 12 3.5.3. Corrections . . . . . . . . . . . . . . . . . . . . . 12 3.5.4. ACP 127 Message Identifier . . . . . . . . . . . . . . 12 3.5.5. Originator PLAD . . . . . . . . . . . . . . . . . . . 12 3.5.6. Codress Message Indicator . . . . . . . . . . . . . . 13 3.5.7. ACP 127 Notification Request . . . . . . . . . . . . . 13 3.5.8. ACP 127 Notification Response . . . . . . . . . . . . 13 4. Security Services . . . . . . . . . . . . . . . . . . . . . . 13 4.1. Access Control . . . . . . . . . . . . . . . . . . . . . . 13 4.2. Authentication of Origin . . . . . . . . . . . . . . . . . 13 4.3. Non-repudiation of Origin . . . . . . . . . . . . . . . . 13 4.4. Message Integrity . . . . . . . . . . . . . . . . . . . . 13 4.5. Message Data Separation . . . . . . . . . . . . . . . . . 13 4.6. Security Labels . . . . . . . . . . . . . . . . . . . . . 13 4.7. Non-repudiation of Receipt . . . . . . . . . . . . . . . . 13 4.8. Secure Mailing Lists . . . . . . . . . . . . . . . . . . . 13 Melnikov, et al. Expires August 29, 2013 [Page 3] Internet-Draft MMHS over SMTP February 2013 4.9. Message Counter Signature . . . . . . . . . . . . . . . . 13 4.10. Certificate Binding . . . . . . . . . . . . . . . . . . . 13 4.11. Compressed Data . . . . . . . . . . . . . . . . . . . . . 13 5. Requirements on Mail User Agents . . . . . . . . . . . . . . . 13 5.1. Standards Compliance . . . . . . . . . . . . . . . . . . . 13 5.2. Audit Trail and Logging . . . . . . . . . . . . . . . . . 14 6. Requirements on Mail Submission Agents . . . . . . . . . . . . 14 6.1. Standards Compliance . . . . . . . . . . . . . . . . . . . 14 6.2. Audit Trail and Logging . . . . . . . . . . . . . . . . . 15 7. Requirements on Mail Transfer Agents . . . . . . . . . . . . . 15 7.1. Standards Compliance . . . . . . . . . . . . . . . . . . . 15 7.2. Audit Trail and Logging . . . . . . . . . . . . . . . . . 16 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 9. Security Considerations . . . . . . . . . . . . . . . . . . . 16 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16 10.1. Normative References . . . . . . . . . . . . . . . . . . . 16 10.2. Informative References . . . . . . . . . . . . . . . . . . 18 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 18 Melnikov, et al. Expires August 29, 2013 [Page 4] Internet-Draft MMHS over SMTP February 2013 1. Introduction A Military Message Handling System (MMHS) processes formal messages ensuring release, distribution, security, and timely delivery across national and international strategic and tactical networks. The MMHS Elements of Service are defined as a set of extensions to the ITU-T X.400 (1992) international standards and are specified in STANAG 4406 Edition 2 or ACP 123. This document specifies how a comparable messaging service can be provided using Email Message Format [RFC5322], SMTP [RFC5321] and their extensions. 2. Conventions Used in This Document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 3. Elements of Service Melnikov, et al. Expires August 29, 2013 [Page 5] Internet-Draft MMHS over SMTP February 2013 3.1. Profile Support +----------------+-----------+---------+------------+---------------+ | Element of | Reference | Support | SMTP | Header | | Service | | | Standard | Field/Paramet | | | | | | er | +----------------+-----------+---------+------------+---------------+ | Access | [ACP123], | MUST | N/A | N/A | | Management | 205a | | | | | Content Type | [ACP123], | MUST | [RFC6477], | MMHS-Extended | | Indication | 205b | | 3.2 | -Authorizatio | | | | | | n-Info | | Converted | [ACP123], | N/A | N/A | N/A | | Indication | 205c | | | | | Delivery Time | [ACP123], | MUST | [RFC5322], | Received | | Stamp | 205d | | 3.6.7 | | | Indication | | | | | | MM | [ACP123], | MUST | [RFC5322], | Message-ID | | Identification | 205e | | 3.6.4 | | | Message | [ACP123], | MUST | [RFC3461], | ENVID | | Identification | 205f | | 4.4 | | | Non-delivery | [ACP123], | MUST | [RFC3461], | NOTIFY=FAILUR | | Notification | 205g | | 4.1 | E | | Original | [ACP123], | N/A | N/A | N/A | | Encoded | 205h | | | | | Information | | | | | | Types | | | | | | Submission | [ACP123], | MUST | [RFC5322], | Date | | Time Stamp | 205i | | 3.6.1 | | | Indication | | | | | | Typed Body | [ACP123], | MUST | [RFC2045], | Content-Type | | | 205j | | 5 | | | User/UA | [ACP123], | N/A | N/A | N/A | | Capabilities | 205k | | | | | Registration | | | | | | Alternate | [ACP123], | N/A | N/A | N/A | | Recipient | 206a | | | | | Allowed | | | | | | Alternate | [ACP123], | N/A | N/A | N/A | | Recipient | 206b | | | | | Assignment | | | | | | Authorising | [ACP123], | MUST | [RFC5322], | From | | Users | 206c | | 3.6.2 | | | Indication | | | | | | Auto-forwarded | [ACP123], | MAY | [RFC2156], | Auto-forwarde | | Indication | 206d | | 2.3.1.2 | d | Melnikov, et al. Expires August 29, 2013 [Page 6] Internet-Draft MMHS over SMTP February 2013 | Blind Copy | [ACP123], | MUST | [RFC5322], | Bcc | | Recipient | 206e | | 3.6.3 | | | Indication | | | | | | Body Part | [ACP123], | N/A | N/A | N/A | | Encryption | 206f | | | | | Indication | | | | | | Conversion | [ACP123], | MAY | [RFC2156], | Conversion | | Prohibited | 206g | | 5.3.6 | | | Conversion | [ACP123], | MAY | [RFC2156], | Conversion-Wi | | Prohibition in | 206h | | 5.3.6 | th-Loss | | Case of Loss | | | | | | of Information | | | | | | Cross | [ACP123], | MAY | [RFC5322], | References | | Referencing | 206i | | 3.6.4 | | | Indication | | | | | | Cross | [ACP123], | MAY | [RFC5322], | References | | Referencing | 206i | | 3.6.4 | | | Indication | | | | | | Deferred | [ACP123], | MAY | [RFC4865], | HOLDUNTIL | | Delivery | 206j | | 3.6.4 | | | Deferred | [ACP123], | N/A | N/A | N/A | | Delivery | 206k | | | | | Cancellation | | | | | | Delivery | [ACP123], | MUST | [RFC3461], | NOTIFY=SUCCES | | Notification | 206l | | 4.1 | S | | Designation of | [ACP123], | N/A | N/A | N/A | | Recipient by | 206m | | | | | Directory Name | | | | | | Disclosure of | [ACP123], | N/A | N/A | N/A | | Other | 206n | | | | | Recipients | | | | | | DL Expansion | [ACP123], | N/A | N/A | N/A | | History | 206o | | | | | Indication | | | | | | DL Expansion | [ACP123], | N/A | N/A | N/A | | Prohibited | 206p | | | | | Expiry Date | [ACP123], | MUST | [RFC2156], | Expires | | Indication | 206q | | 2.3.1.2 | | | Explicit | [ACP123], | N/A | N/A | N/A | | Conversion | 206r | | | | | Forwarded MM | [ACP123], | MUST | [RFC2046], | Content-Type: | | Indication | 206s | | 5.2 | message/rfc82 | | | | | | 2 | | Grade of | [ACP123], | MUST | [RFC6758] | MT-Priority | | Delivery | 206t | | | | | Selection | | | | | | Hold for | [ACP123], | N/A | N/A | N/A | | Delivery | 206u | | | | Melnikov, et al. Expires August 29, 2013 [Page 7] Internet-Draft MMHS over SMTP February 2013 | Incomplete | [ACP123], | MAY | [RFC2156], | Incomplete-Co | | Copy | 206v | | 2.3.1.2 | py | | Indication | | | | | | Language | [ACP123], | MAY | [RFC3282], | Content-Langu | | Indication | 206w | | 2 | age | | Latest | [ACP123], | MUST | [RFC2852], | BY | | Delivery | 206x | | 4 | | | Designation | | | | | | Multi-destinat | [ACP123], | MUST | [RFC5321], | RCPT TO | | ion Delivery | 206y | | 2.1 | | | Multi-part | [ACP123], | MUST | [RFC2046], | Content-Type: | | Body | 206z | | 25.1.3 | multipart/mix | | | | | | ed | | Non-receipt | [ACP123], | MUST | [RFC3798], | Disposition-N | | Notification | 206aa | | 2.1 | otification-T | | Request | | | | o | | Indication | | | | | | Obsoleting | [ACP123], | MAY | [RFC2156], | Supersedes | | Indication | 206ab | | 2.3.1.2 | | +----------------+-----------+---------+------------+---------------+ 3.2. Basic Elements of Service 3.2.1. Access Management This element of service enables an Mail User Agent and an Mail Transfer Agent to establish access and manage information associated with access establishment. This includes the ability to identify and validate the identity of the other. Strong authentication in the bind operation is mandatory. Strong authentication SHALL be supported using SMTP Extension for Authentication [RFC4954] and SMTP Extension for Secure SMTP over TLS [RFC3207]. [[Q: Do we need to identify the SASL mechanisms to use here?]] 3.2.2. Content Type Indication This element of service enables an originating Mail User Agent to indicate the type of each submitted message. In most cases, the content type will be obvious from the header fields that are present. A Military Message SHALL be indicated using the MMHS-Extended- Authorization-Info header field defined in [RFC6477]. Melnikov, et al. Expires August 29, 2013 [Page 8] Internet-Draft MMHS over SMTP February 2013 3.2.3. Converted Indication [[TBD]] 3.2.4. Delivery Time Stamp Indication This element of service indicates to each recipient Mail User Agent (i.e., on a per-recipient basis), the date and time at which the Mail Transfer Agent delivered a message. The delivery time stamp SHALL be determined from the first Received header field, defined in [RFC5322], present in the message. 3.2.5. MM Identification This element of service enables cooperating Mail User Agents to convey a globally unique identifier for each Military Message sent or received. This identifier is used in subsequent messages to identify the original Military Message. A Military Message SHALL be uniquely identified using the Message-ID header field defined in [RFC5322]. 3.2.6. Message Identification This element of service is used by Mail User Agents and the Mail Transfer Agents to refer to a previously submitted message in connection with other elements of service such as delivery and non- delivery notification. Message Identification SHALL be specified by the Mail User Agent using the ENVID parameter, as defined in [RFC3461]. The Mail Transfer Agent SHALL return the message identification in the Original-Envelope-Id field of a message/delivery status as defined in [RFC3461]. 3.2.7. Non-delivery Notification This element of service allows a Mail User Agent to ask for the MTS to notify the originator if a submitted message was not delivered to the specified recipient Mail User Agent. The MMHS must, with a high degree of certainty, deliver a message to the intended recipient(s). If the system cannot deliver a message within a determined period of time , a non-delivery report will be returned to the originating Mail User Agent by the MMHS. The non-delivery report contains information to enable it to be mapped to the appropriate message (i.e., the message identification), recipient information, as well as information about why the message could not be delivered. Melnikov, et al. Expires August 29, 2013 [Page 9] Internet-Draft MMHS over SMTP February 2013 Non-Delivery notifications SHALL be generated in accordance with [RFC3461]. Note that non-delivery notifications are requested on a per message basis in this profile, and not on a per recipient basis as defined in [ACP123]. 3.2.8. Original Encoded Information Types 3.2.9. Submission Time Stamp Indication 3.2.10. Typed Body 3.2.11. User/UA Capabilities Registration 3.3. Optional Elements of Service 3.3.1. Alternate Recipient Allowed 3.3.2. Alternate Recipient Allowed 3.3.3. Alternate Recipient Assignment 3.3.4. Authorizing Users Indication 3.3.5. Auto-forwarded Indication 3.3.6. Blind Copy Recipient Indication 3.3.7. Body Part Encryption Indication 3.3.8. Conversion Prohibited 3.3.9. Conversion Prohibition in Case of Loss of Information 3.3.10. Cross Referencing Indication 3.3.11. Deferred Delivery [RFC4865] 3.3.12. Deferred Delivery Cancellation Deferred Delivery Cancellation is not supported by this profile. 3.3.13. Delivery Notification Melnikov, et al. Expires August 29, 2013 [Page 10] Internet-Draft MMHS over SMTP February 2013 3.3.14. Designation of Recipient by Directory Name 3.3.15. Disclosure of Other Recipients 3.3.16. DL Expansion History Indication 3.3.17. DL Expansion Prohibited 3.3.18. Expiry Date Indication 3.3.19. Explicit Conversion 3.3.20. Forwarded MM Indication 3.3.21. Grade of Delivery Selection 3.3.22. Hold for Delivery 3.3.23. Incomplete Copy Indication 3.3.24. Language Indication 3.3.25. Latest Delivery Designation 3.3.26. Multi-destination Delivery 3.3.27. Multi-part Body 3.3.28. Non-receipt Notification Request Indication 3.3.29. Obsoleting Indication 3.3.30. Originator Indication 3.3.31. Originator Requested Alternate Recipient 3.3.32. Prevention of Non-delivery Notification 3.3.33. Primary and Copy Recipients Indication 3.3.34. Receipt Notification Request Indication 3.3.35. Redirection Disallowed by Originator 3.3.36. Redirection of Incoming Messages 3.3.37. Reply Request Indication Melnikov, et al. Expires August 29, 2013 [Page 11] Internet-Draft MMHS over SMTP February 2013 3.3.38. Replying MM Indication 3.3.39. Requested Preferred Delivery Method 3.3.40. Subject Indication 3.3.41. Use of Distribution List 3.4. Military Elements of Service [[These are all derived from RFC6477 - highlighting those that are not supported by this profile]]. 3.4.1. Primary Precedence 3.4.2. Copy Precedence 3.4.3. Message Type 3.4.4. Exempted Addresses 3.4.5. Extended Authorization Info 3.4.6. Distribution Code 3.4.7. Message Instructions 3.4.8. Clear Service 3.4.9. Other Recipient Indicator 3.4.10. Originator Reference 3.4.11. Use of Address List 3.5. Transition Elements of Service 3.5.1. Handling Instructions 3.5.2. Pilot Forwarded 3.5.3. Corrections 3.5.4. ACP 127 Message Identifier 3.5.5. Originator PLAD Melnikov, et al. Expires August 29, 2013 [Page 12] Internet-Draft MMHS over SMTP February 2013 3.5.6. Codress Message Indicator 3.5.7. ACP 127 Notification Request 3.5.8. ACP 127 Notification Response 4. Security Services [[Follow ACP123(B) Annex B Section 7 which describes how the security services are mapped onto S/MIME mechanisms. However, it references the NATO S/MIME Profile (STANAG 4631) which is not publically accessible, so we will have restate here.]] 4.1. Access Control 4.2. Authentication of Origin 4.3. Non-repudiation of Origin 4.4. Message Integrity 4.5. Message Data Separation 4.6. Security Labels 4.7. Non-repudiation of Receipt 4.8. Secure Mailing Lists 4.9. Message Counter Signature 4.10. Certificate Binding 4.11. Compressed Data 5. Requirements on Mail User Agents 5.1. Standards Compliance A Mail User Agent (MUA) compliant with this specification MUST support 1. Internet Message Format [RFC5322]. 2. Multipurpose Internet Mail Extensions (MIME) [RFC2045] [RFC2046] [RFC2047] [RFC2049]. [[Maybe be a bit more specific about what is required?]] Melnikov, et al. Expires August 29, 2013 [Page 13] Internet-Draft MMHS over SMTP February 2013 3. Parsing, processing and having the ability to generate MMHS header fields [RFC6477]. 4. The ability to insert MT-Priority header field [RFC6758]. 5. Parsing and processing of Multipart/Report Content Type for the Reporting of Mail System Administrative Messages [RFC6522] containing message/delivery-status [RFC3464] and Message Disposition Notification (MDN) [RFC3798]. 6. The ability to request an MDN and the ability to generate an MDN in response to a request [RFC3798]. 7. The ability to send and receive signed and encrypted S/MIME messages [RFC5652] [RFC5751]. 8. The ability to send and receive ESS Security Labels [RFC2634]. MUA can also take advantage of SMTP extensions advertised by MSAs (see Section 6). 5.2. Audit Trail and Logging 6. Requirements on Mail Submission Agents 6.1. Standards Compliance In addition to the list of requirements specified in [RFC6409], an Mail Submission Agent (MSA) compliant with this specification MUST support: 1. SMTP Extension for Authentication [RFC4954]. 2. SMTP Extension for Secure SMTP over TLS [RFC3207]. 3. SMTP Service Extension for Returning Enhanced Error Codes [RFC2034]. 4. Deliver By SMTP Service Extension [RFC2852]. 5. SMTP extension for Message Transfer Priorities. [RFC6710] "STANAG4406" Priority Assignment Policy MUST be advertised in the EHLO response. The MSA MUST be able to handle the MT- Priority header field as specified in [RFC6758]. 6. SMTP extension for for Delivery Status Notifications [RFC3461]. Melnikov, et al. Expires August 29, 2013 [Page 14] Internet-Draft MMHS over SMTP February 2013 7. SMTP Extension for 8-bit MIME transport [RFC6152]. 8. SMTP Extension for Message Size Declaration [RFC1870]. 9. SMTP Extension for Command Pipelining [RFC2920]. 10. SMTP Extensions for Transmission of Large and Binary MIME Messages [RFC3030]. The following SMTP extensions are OPTIONAL to support in MSAs compliant with this specification: 1. SMTP Submission Service Extension for Future Message Release [RFC4865]. 6.2. Audit Trail and Logging 7. Requirements on Mail Transfer Agents 7.1. Standards Compliance A Mail Transfer Agent (MTA) compliant with this specification MUST support 1. SMTP Service Extension for Returning Enhanced Error Codes [RFC2034]. 2. Deliver By SMTP Service Extension [RFC2852]. 3. SMTP extension for Message Transfer Priorities [RFC6710]. "STANAG4406" Priority Assignment Policy MUST be advertised in the EHLO response. The MTA MUST be able to handle the MT-Priority header field as specified in [RFC6758]. 4. SMTP extension for for Delivery Status Notifications [RFC3461]. 5. SMTP Extension for 8-bit MIME transport [RFC6152]. 6. SMTP Extension for Message Size Declaration [RFC1870]. 7. SMTP Extension for Command Pipelining [RFC2920]. 8. SMTP Extensions for Transmission of Large and Binary MIME Messages [RFC3030]. The following SMTP extensions SHOULD be supported in MTAs compliant with this specification: Melnikov, et al. Expires August 29, 2013 [Page 15] Internet-Draft MMHS over SMTP February 2013 1. SMTP Extension for Secure SMTP over TLS [RFC3207]. 7.2. Audit Trail and Logging 8. IANA Considerations This document doesn't ask for any action from IANA. 9. Security Considerations TBD 10. References 10.1. Normative References [RFC2033] Myers, J., "Local Mail Transfer Protocol", RFC 2033, October 1996. [RFC2034] Freed, N., "SMTP Service Extension for Returning Enhanced Error Codes", RFC 2034, October 1996. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3461] Moore, K., "Simple Mail Transfer Protocol (SMTP) Service Extension for Delivery Status Notifications (DSNs)", RFC 3461, January 2003. [RFC5321] Klensin, J., "Simple Mail Transfer Protocol", RFC 5321, October 2008. [RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322, October 2008. [RFC6409] Gellens, R. and J. Klensin, "Message Submission for Mail", STD 72, RFC 6409, November 2011. [RFC1870] Klensin, J., Freed, N., and K. Moore, "SMTP Service Extension for Message Size Declaration", STD 10, RFC 1870, November 1995. [RFC2852] Newman, D., "Deliver By SMTP Service Extension", RFC 2852, June 2000. [RFC2920] Freed, N., "SMTP Service Extension for Command Pipelining", STD 60, RFC 2920, September 2000. Melnikov, et al. Expires August 29, 2013 [Page 16] Internet-Draft MMHS over SMTP February 2013 [RFC3030] Vaudreuil, G., "SMTP Service Extensions for Transmission of Large and Binary MIME Messages", RFC 3030, December 2000. [RFC4865] White, G. and G. Vaudreuil, "SMTP Submission Service Extension for Future Message Release", RFC 4865, May 2007. [RFC6152] Klensin, J., Freed, N., Rose, M., and D. Crocker, "SMTP Service Extension for 8-bit MIME Transport", STD 71, RFC 6152, March 2011. [RFC4954] Siemborski, R. and A. Melnikov, "SMTP Service Extension for Authentication", RFC 4954, July 2007. [RFC3207] Hoffman, P., "SMTP Service Extension for Secure SMTP over Transport Layer Security", RFC 3207, February 2002. [RFC6477] Melnikov, A. and G. Lunt, "Registration of Military Message Handling System (MMHS) Header Fields for Use in Internet Mail", RFC 6477, January 2012. [RFC6710] Melnikov, A. and K. Carlberg, "Simple Mail Transfer Protocol Extension for Message Transfer Priorities", RFC 6710, August 2012. [RFC6758] Melnikov, A. and K. Carlberg, "Tunneling of SMTP Message Transfer Priorities", RFC 6758, October 2012. [RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies", RFC 2045, November 1996. [RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, November 1996. [RFC2047] Moore, K., "MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text", RFC 2047, November 1996. [RFC2049] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and Examples", RFC 2049, November 1996. [RFC2634] Hoffman, P., "Enhanced Security Services for S/MIME", RFC 2634, June 1999. Melnikov, et al. Expires August 29, 2013 [Page 17] Internet-Draft MMHS over SMTP February 2013 [RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", STD 70, RFC 5652, September 2009. [RFC5751] Ramsdell, B. and S. Turner, "Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.2 Message Specification", RFC 5751, January 2010. [RFC3464] Moore, K. and G. Vaudreuil, "An Extensible Message Format for Delivery Status Notifications", RFC 3464, January 2003. [RFC6522] Kucherawy, M., "The Multipart/Report Media Type for the Reporting of Mail System Administrative Messages", STD 73, RFC 6522, January 2012. [RFC3798] Hansen, T. and G. Vaudreuil, "Message Disposition Notification", RFC 3798, May 2004. [RFC3282] Alvestrand, H., "Content Language Headers", RFC 3282, May 2002. [ACP123] CCEB, "Common Messaging Strategy and Procedures", ACP 123, May 2009. 10.2. Informative References [RFC5598] Crocker, D., "Internet Mail Architecture", RFC 5598, July 2009. [RFC2156] Kille, S., "MIXER (Mime Internet X.400 Enhanced Relay): Mapping between X.400 and RFC 822/MIME", RFC 2156, January 1998. [RFC6376] Crocker, D., Hansen, T., and M. Kucherawy, "DomainKeys Identified Mail (DKIM) Signatures", RFC 6376, September 2011. [STANAG-4406] NATO, "STANAG 4406 Edition 2: Military Message Handling System", STANAG 4406, March 2005. Appendix A. Acknowledgements Many thanks for input provided by Steve Kille and David Wilson. Melnikov, et al. Expires August 29, 2013 [Page 18] Internet-Draft MMHS over SMTP February 2013 Authors' Addresses Alexey Melnikov Isode Ltd 5 Castle Business Village 36 Station Road Hampton, Middlesex TW12 2BX UK EMail: Alexey.Melnikov@isode.com Graeme Lunt SMHS Ltd Bescar Moss Farm Bescar Lane Ormskirk L40 9QN UK EMail: graeme.lunt@smhs.co.uk Alan Ross SMHS Ltd Bescar Moss Farm Bescar Lane Ormskirk L40 9QN UK EMail: alan.ross@smhs.co.uk Melnikov, et al. Expires August 29, 2013 [Page 19]