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Permanent Message Header Field Names

Registry Name: Permanent Message Header Field Names    
Reference: [RFC3864]    
Registration Procedures: Expert Review (Expert: Graham Klyne)    
Note: This page is obsolete. For the current version, please see http://www.iana.org/assignments/message-headers.

[RFC5504] specified that no new header fields be registered that begin with "Downgraded-". That restriction is now lifted, per [RFC-ietf-eai-popimap-downgrade-08]. 		   
 
Header Field Name
Protocol
Status
Reference
A-IM http   [RFC4229]
Accept http   [RFC4229]
Accept-Additions http   [RFC4229]
Accept-Charset http   [RFC4229]
Accept-Encoding http   [RFC4229]
Accept-Features http   [RFC4229]
Accept-Language http   [RFC4229]
Accept-Language mail   [RFC4021]
Accept-Patch http   [RFC5789]
Accept-Ranges http   [RFC4229]
Age http   [RFC4229]
Allow http   [RFC4229]
Also-Control netnews obsoleted [Son-of-1036]
Alternate-Recipient mail   [RFC4021]
Alternates http   [RFC4229]
Apply-To-Redirect-Ref http   [RFC4437]
Approved netnews standard [RFC5536]
Archive netnews standard [RFC5536]
Archived-At mail standard [RFC5064]
Archived-At netnews standard [RFC5064]
Article-Names netnews obsoleted [Son-of-1036]
Article-Updates netnews obsoleted [Son-of-1036]
Authentication-Info http   [RFC4229]
Authentication-Results mail standard [RFC5451]
Authorization http   [RFC4229]
Auto-Submitted mail standard [RFC3834] (section 5)
Autoforwarded mail   [RFC4021]
Autosubmitted mail   [RFC4021]
Base MIME obsoleted [RFC1808];[RFC2068], Section 14.11
Bcc mail standard [RFC5322]
Body none reserved [RFC6068]
C-Ext http   [RFC4229]
C-Man http   [RFC4229]
C-Opt http   [RFC4229]
C-PEP http   [RFC4229]
C-PEP-Info http   [RFC4229]
Cache-Control http   [RFC4229]
Cc mail standard [RFC5322]
Comments mail standard [RFC5322]
Comments netnews standard [RFC5536][RFC5322]
Connection http   [RFC4229]
Content-Alternative MIME   [RFC4021]
Content-Base http obsoleted [RFC2068][RFC2616]
Content-Base MIME obsoleted [RFC2110][RFC2557]
Content-Description MIME   [RFC4021]
Content-Disposition http standard [RFC6266]
Content-Disposition MIME   [RFC4021]
Content-Duration MIME   [RFC4021]
Content-Encoding http   [RFC4229]
Content-features MIME   [RFC4021]
Content-ID http   [RFC4229]
Content-ID MIME   [RFC4021]
Content-Identifier mail   [RFC4021]
Content-Language http   [RFC4229]
Content-Language MIME   [RFC4021]
Content-Length http   [RFC4229]
Content-Location http   [RFC4229]
Content-Location MIME   [RFC4021]
Content-MD5 http   [RFC4229]
Content-MD5 MIME   [RFC4021]
Content-Range http   [RFC4229]
Content-Return mail   [RFC4021]
Content-Script-Type http   [RFC4229]
Content-Style-Type http   [RFC4229]
Content-Transfer-Encoding MIME   [RFC4021]
Content-Type http   [RFC4229]
Content-Type MIME   [RFC4021]
Content-Version http   [RFC4229]
Control netnews standard [RFC5536]
Conversion mail   [RFC4021]
Conversion-With-Loss mail   [RFC4021]
Cookie http standard [RFC6265]
Cookie2 http obsoleted [RFC2965][RFC6265]
DASL http standard [RFC5323]
DAV http standard [RFC4918]
DL-Expansion-History mail   [RFC4021]
Date http   [RFC4229]
Date mail standard [RFC5322]
Date netnews standard [RFC5536][RFC5322]
Date-Received netnews obsoleted [RFC0850]
Default-Style http   [RFC4229]
Deferred-Delivery mail   [RFC4021]
Delivery-Date mail   [RFC4021]
Delta-Base http   [RFC4229]
Depth http standard [RFC4918]
Derived-From http   [RFC4229]
Destination http standard [RFC4918]
Differential-ID http   [RFC4229]
Digest http   [RFC4229]
Discarded-X400-IPMS-Extensions mail   [RFC4021]
Discarded-X400-MTS-Extensions mail   [RFC4021]
Disclose-Recipients mail   [RFC4021]
Disposition-Notification-Options mail   [RFC4021]
Disposition-Notification-To mail   [RFC4021]
Distribution netnews standard [RFC5536]
DKIM-Signature mail standard [RFC6376]
Downgraded-Bcc mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Cc mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Disposition-Notification-To mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Final-Recipient mail standard [RFC-ietf-eai-popimap-downgrade-08], Section 3.1.10
Downgraded-From mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-In-Reply-To mail standard [RFC-ietf-eai-popimap-downgrade-08], Section 3.1.10
Downgraded-Mail-From mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Message-Id mail standard [RFC-ietf-eai-popimap-downgrade-08], Section 3.1.10
Downgraded-Original-Recipient mail standard [RFC-ietf-eai-popimap-downgrade-08], Section 3.1.10
Downgraded-Rcpt-To mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-References mail standard [RFC-ietf-eai-popimap-downgrade-08], Section 3.1.10
Downgraded-Reply-To mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Resent-Bcc mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Resent-Cc mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Resent-From mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Resent-Reply-To mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Resent-Sender mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Resent-To mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Return-Path mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-Sender mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Downgraded-To mail obsoleted [RFC5504][RFC-ietf-eai-popimap-downgrade-08]
Encoding mail   [RFC4021]
Encrypted mail   [RFC4021]
ETag http   [RFC4229]
Expect http   [RFC4229]
Expires http   [RFC4229]
Expires mail   [RFC4021]
Expires netnews standard [RFC5536]
Expiry-Date mail   [RFC4021]
Ext http   [RFC4229]
Followup-To netnews standard [RFC5536]
Forwarded http standard [RFC-ietf-appsawg-http-forwarded-10]
From http   [RFC4229]
From mail standard [RFC5322][RFC-leiba-5322upd-from-group-09]
From netnews standard [RFC5536][RFC5322]
Generate-Delivery-Report mail   [RFC4021]
GetProfile http   [RFC4229]
Host http   [RFC4229]
IM http   [RFC4229]
If http standard [RFC4918]
If-Match http   [RFC4229]
If-Modified-Since http   [RFC4229]
If-None-Match http   [RFC4229]
If-Range http   [RFC4229]
If-Schedule-Tag-Match http standard [RFC-desruisseaux-caldav-sched-12]
If-Unmodified-Since http   [RFC4229]
Importance mail   [RFC4021]
In-Reply-To mail standard [RFC5322]
Incomplete-Copy mail   [RFC4021]
Injection-Date netnews standard [RFC5536]
Injection-Info netnews standard [RFC5536]
Keep-Alive http   [RFC4229]
Keywords mail standard [RFC5322]
Keywords netnews standard [RFC5536][RFC5322]
Label http   [RFC4229]
Language mail   [RFC4021]
Last-Modified http   [RFC4229]
Latest-Delivery-Time mail   [RFC4021]
Lines netnews deprecated [RFC5536][RFC3977]
Link http   [RFC5988]
List-Archive mail   [RFC4021]
List-Help mail   [RFC4021]
List-ID mail   [RFC4021]
List-Owner mail   [RFC4021]
List-Post mail   [RFC4021]
List-Subscribe mail   [RFC4021]
List-Unsubscribe mail   [RFC4021]
Location http   [RFC4229]
Lock-Token http standard [RFC4918]
Man http   [RFC4229]
Max-Forwards http   [RFC4229]
Message-Context mail   [RFC4021]
Message-ID mail standard [RFC5322]
Message-ID netnews standard [RFC5536][RFC5322]
Message-Type mail   [RFC4021]
Meter http   [RFC4229]
MIME-Version http   [RFC4229]
MIME-Version MIME   [RFC4021]
MMHS-Exempted-Address mail   [RFC6477][ACP123], Appendix A1.1 and Appendix B.105
MMHS-Extended-Authorisation-Info mail   [RFC6477][ACP123], Appendix A1.2 and Appendix B.106
MMHS-Subject-Indicator-Codes mail   [RFC6477][ACP123], Appendix A1.3 and Appendix B.107
MMHS-Handling-Instructions mail   [RFC6477][ACP123], Appendix A1.4 and Appendix B.108
MMHS-Message-Instructions mail   [RFC6477][ACP123], Appendix A1.5 and Appendix B.109
MMHS-Codress-Message-Indicator mail   [RFC6477][ACP123], Appendix A1.6 and Appendix B.110
MMHS-Originator-Reference mail   [RFC6477][ACP123], Appendix A1.7 and Appendix B.111
MMHS-Primary-Precedence mail   [RFC6477][ACP123], Appendix A1.8 and Appendix B.101
MMHS-Copy-Precedence mail   [RFC6477][ACP123], Appendix A1.9 and Appendix B.102
MMHS-Message-Type mail   [RFC6477][ACP123], Appendix A1.10 and Appendix B.103
MMHS-Other-Recipients-Indicator-To mail   [RFC6477][ACP123], Appendix A1.12 and Appendix B.113
MMHS-Other-Recipients-Indicator-CC mail   [RFC6477][ACP123], Appendix A1.12 and Appendix B.113
MMHS-Acp127-Message-Identifier mail   [RFC6477][ACP123], Appendix A1.14 and Appendix B.116
MMHS-Originator-PLAD mail   [RFC6477][ACP123], Appendix A1.15 and Appendix B.117
MT-Priority mail standard [RFC6758]
Negotiate http   [RFC4229]
Newsgroups netnews standard [RFC5536]
NNTP-Posting-Date netnews obsoleted [None]
NNTP-Posting-Host netnews obsoleted [RFC2980]
Obsoletes mail   [RFC4021]
Opt http   [RFC4229]
Ordering-Type http standard [RFC4229]
Organization netnews standard [RFC5536]
Origin http standard [RFC6454]
Original-Encoded-Information-Types mail   [RFC4021]
Original-From mail standard [RFC5703]
Original-Message-ID mail   [RFC4021]
Original-Recipient mail standard [RFC3798][RFC5337]
Original-Sender netnews standard [RFC5537]
Originator-Return-Address mail   [RFC4021]
Original-Subject mail standard [RFC5703]
Overwrite http standard [RFC4918]
P3P http   [RFC4229]
Path netnews standard [RFC5536]
PEP http   [RFC4229]
PICS-Label http   [RFC4229]
PICS-Label mail   [RFC4021]
Pep-Info http   [RFC4229]
Position http standard [RFC4229]
Posting-Version netnews obsoleted [RFC0850]
Pragma http   [RFC4229]
Prefer http standard [RFC-snell-http-prefer-18]
Preference-Applied http standard [RFC-snell-http-prefer-18]
Prevent-NonDelivery-Report mail   [RFC4021]
Priority mail   [RFC4021]
ProfileObject http   [RFC4229]
Protocol http   [RFC4229]
Protocol-Info http   [RFC4229]
Protocol-Query http   [RFC4229]
Protocol-Request http   [RFC4229]
Proxy-Authenticate http   [RFC4229]
Proxy-Authentication-Info http   [RFC4229]
Proxy-Authorization http   [RFC4229]
Proxy-Features http   [RFC4229]
Proxy-Instruction http   [RFC4229]
Public http   [RFC4229]
Range http   [RFC4229]
Received mail standard [RFC5322][RFC5321]
Received-SPF mail   [RFC4408]
Redirect-Ref http   [RFC4437]
References mail standard [RFC5322]
References netnews standard [RFC5536][RFC5322]
Referer http   [RFC4229]
Relay-Version netnews obsoleted [RFC0850]
Reply-By mail   [RFC4021]
Reply-To mail standard [RFC5322]
Reply-To netnews standard [RFC5536][RFC5322]
Resent-Bcc mail standard [RFC5322]
Resent-Cc mail standard [RFC5322]
Resent-Date mail standard [RFC5322]
Resent-From mail standard [RFC5322][RFC-leiba-5322upd-from-group-09]
Resent-Message-ID mail standard [RFC5322]
Resent-Reply-To mail obsoleted [RFC5322]
Resent-Sender mail standard [RFC5322][RFC-leiba-5322upd-from-group-09]
Resent-To mail standard [RFC5322]
Retry-After http   [RFC4229]
Return-Path mail standard [RFC5322]
Safe http   [RFC4229]
Schedule-Reply http standard [RFC-desruisseaux-caldav-sched-12]
Schedule-Tag http standard [RFC-desruisseaux-caldav-sched-12]
Sec-WebSocket-Accept http standard [RFC6455]
Sec-WebSocket-Extensions http standard [RFC6455]
Sec-WebSocket-Key http standard [RFC6455]
Sec-WebSocket-Protocol http standard [RFC6455]
Sec-WebSocket-Version http standard [RFC6455]
Security-Scheme http   [RFC4229]
See-Also netnews obsoleted [Son-of-1036]
Sender mail standard [RFC5322][RFC-leiba-5322upd-from-group-09]
Sender netnews standard [RFC5536][RFC5322]
Sensitivity mail   [RFC4021]
Server http   [RFC4229]
Set-Cookie http standard [RFC6265]
Set-Cookie2 http obsoleted [RFC2965][RFC6265]
SetProfile http   [RFC4229]
SLUG http standard [RFC5023]
SoapAction http   [RFC4229]
Solicitation mail   [RFC3865]
Status-URI http   [RFC4229]
Strict-Transport-Security http standard [RFC6797]
Subject mail standard [RFC5322]
Subject netnews standard [RFC5536][RFC5322]
Summary netnews standard [RFC5536]
Supersedes mail   [RFC4021]
Supersedes netnews standard [RFC5536][RFC2156]
Surrogate-Capability http   [RFC4229]
Surrogate-Control http   [RFC4229]
TCN http   [RFC4229]
TE http   [RFC4229]
Timeout http standard [RFC4918]
To mail standard [RFC5322]
Trailer http   [RFC4229]
Transfer-Encoding http   [RFC4229]
URI http   [RFC4229]
Upgrade http   [RFC4229]
User-Agent http   [RFC4229]
User-Agent netnews standard [RFC5536][RFC2616]
Variant-Vary http   [RFC4229]
Vary http   [RFC4229]
VBR-Info mail standard [RFC5518]
Via http   [RFC4229]
WWW-Authenticate http   [RFC4229]
Want-Digest http   [RFC4229]
Warning http   [RFC4229]
X400-Content-Identifier mail   [RFC4021]
X400-Content-Return mail   [RFC4021]
X400-Content-Type mail   [RFC4021]
X400-MTS-Identifier mail   [RFC4021]
X400-Originator mail   [RFC4021]
X400-Received mail   [RFC4021]
X400-Recipients mail   [RFC4021]
X400-Trace mail   [RFC4021]
Xref netnews standard [RFC5536]

 

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Page updated 2013-03-06
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