152:
specifies a Tree Walk through the parent domains. So, for example, "a.b.c.d.example.com.au" and "example.com.au" have the same
Organizational Domain, because _dmarc.example.com.au is the only defined DMARC record among all the subdomains involved, including _dmarc.au. As this allows domain owners to define domain roles, it is deemed to be more accurate than the
181:(selector) tags specify where in DNS to retrieve the public key for the signature. A valid signature proves that the signer is a domain owner, and that the From field hasn't been modified since the signature was applied. There may be several DKIM signatures on an email message; DMARC requires one valid signature where the domain in the
1102:
have been accused of forcing the costs of their own security failures onto third parties. As of 2020, the FAQ in the official DMARC wiki contains several suggestions for mailing lists to handle messages from a domain with a strict DMARC policy, of which the most widely implemented is the mailing list
71:
entry is published, any receiving email server can authenticate the incoming email based on the instructions published by the domain owner within the DNS entry. If the email passes the authentication, it will be delivered and can be trusted. If the email fails the check, depending on the instructions
1110:
working group was formed in August 2014 in order to address DMARC issues, starting from interoperability concerns and possibly continuing with a revised standard specification and documentation. Meanwhile, the existing DMARC specification had reached an editorial state agreed upon and implemented by
1048:
header field to pass DKIM alignment may bring the message out of compliance with RFC 5322 section 3.6.2: "The 'From:' field specifies the author(s) of the message, that is, the mailbox(es) of the person(s) or system(s) responsible for the writing of the message." Mailbox refers to the author's email
770:
show DMARC-wise results, either pass or fail, taking alignment into account. The rightmost ones, with similar labels, show the name of the domain which claims to participate in the sending of the message and (in parentheses) the authentication status of that claim according to the original protocol,
314:
The protocol provides for various ratchets, or transitional states, to allow mail admins to gradually transition from not implementing DMARC at all the way through to an unyielding setup. The concept of stepwise adoption assumes that the goal of DMARC is the strongest setting, which is not the case
953:
to the domain name, to allocating a temporary user ID where a modified version of the user's address is used, or an opaque ID is used, which keeps the user's "real" email address private from the list. In addition, the display name can be changed so as to show both the author and the list (or list
779:
test; DKIM can appear once for each signature present in the message. In the example, the first row represents the main mail flow from example.org, and the second row is a DKIM glitch, such as signature breakage due to a minor alteration in transit. The third and fourth rows show typical failures
106:
A DMARC policy allows a sender's domain to indicate that their email messages are protected by SPF and/or DKIM, and tells a receiver what to do if neither of those authentication methods passes – such as to reject the message or quarantine it. The policy can also specify how an email receiver can
446:
mentions the "Report Domain", which indicates the DNS domain name about which the report was generated, and the "Submitter", which is the entity issuing the report. The payload is in an attachment with a long filename consisting of bang-separated elements such as the report-issuing receiver, the
305:
In this example, the entity controlling the example.com DNS domain intends to monitor SPF and/or DKIM failure rates and doesn't expect email to be sent from subdomains of example.com. Note that a subdomain can publish its own DMARC record; receivers must check it out before falling back to the
151:
Alignment may be specified as strict or relaxed. For strict alignment, the domain names must be identical. For relaxed alignment, the top-level "Organizational Domain" must match. The
Organizational Domain used to be found by checking a list of public DNS suffixes. The upcoming spec instead
1035:
Wrapping the message works nicely, for those who use an email client which understands wrapped messages. Not doing any change is perhaps the most obvious solution, except that they seem to be legally required in some countries, and that routinely losing SPF authentication may render overall
929:
This workaround keeps the standard mailing list workflow, and is adopted by several large mailing list operators, but precludes the list adding footers and subject prefixes. This requires careful configuration of mailing software to make sure signed headers are not reordered or modified. A
469:
and viewed in a tabular form. The XML schema is defined in
Appendix C of specifications and a raw record is exemplified in dmarc.org. Here we stick with a relational example, which better conveys the nature of the data. DMARC records can also be directly transformed in HTML by applying an
1022:
Altering the author is not fair in general, and can break the expected relationship between meaning and appearance of that datum. It also breaks automated use of it. There are communities which use mailing lists to coordinate their work, and deploy tools which use the
1118:
published a study on DMARC usage by businesses. Out of 569 businesses, the study found about a third implemented any DMARC configuration, fewer than 10% used DMARC to instruct servers to reject unauthenticated messages, and a majority had implemented SPF.
920:
are a frequent cause of legitimate breakage of the original author's domain DKIM signature, for example by adding a prefix to the subject header. A number of workarounds are possible, and mailing list software packages are working on solutions.
2222:
799:. Along with it, not shown in the table, DMARC provides for a policy override. Some reasons why a receiver can apply a policy different from the one requested are already provided for by the specification:
406:
Target email addresses can belong to external domains. In that case, the target domain has to set up a DMARC record to say it agrees to receive them, otherwise it would be possible to exploit reporting for
857:
Forensic
Reports, also known as Failure Reports, are generated in real time and consist of redacted copies of individual messages that failed SPF, DKIM or both based upon what value is specified in the
780:
modes of a forwarder and a mailing list, respectively. DMARC authentication failed for the last row only; it could have affected the message disposition if example.org had specified a strict policy.
336:
asks receivers to treat messages that fail DMARC check with suspicion. Different receivers have different means to implement that, for example flag messages or deliver them in the spam folder.
1079:. The change tried to anticipate the interoperability issues expected in case restrictive policies were applied to domains with human users (as opposed to purely transactional mail domains).
121:
DMARC does not directly address whether or not an email is spam or otherwise fraudulent. Instead, DMARC can require that a message not only pass DKIM or SPF validation, but that it also pass
346:
The policy published can be mitigated by applying it to only a percentage of the messages that fail DMARC check. Receivers are asked to select the given percentage of messages by a simple
465:
The XML content consists of a header, containing the policy on which the report is based and report metadata, followed by a number of records. Records can be put in a database as a
2273:
1994:
The fact that the from field is not rewritten is IMPORTANT because rewriting the from field would break the 'git am' command, since it uses the From: field to fill in the
930:
misconfigured email server may put List-id in its DKIM of messages sent to a mailing list, and then the list operator is forced to reject it or do From: rewriting.
1053:
header is available to indicate that an email was sent on behalf of another party, but DMARC only checks policy for the From domain and ignores the Sender domain.
2097:
1015:, has to be designed in order to accommodate reply-to-author functionality, in which case reply-to-list functionality is covered by the preceding change in the
173:
DKIM allows parts of an email message to be cryptographically signed, and the signature must cover the From field. Within the DKIM-Signature mail header, the
1259:
91:
field presented to end users; how the receiver should deal with failures – and provides a reporting mechanism for actions performed under those policies.
447:
begin and end epochs of the reported period as Unix-style time stamps, an optional unique identifier and an extension which depends on the possible
170:, envelope-from or RFC5321.MailFrom.) In addition to requiring that the SPF check passes, DMARC checks that RFC5321.MailFrom aligns with 5322.From.
1559:
159:
Like SPF and DKIM, DMARC uses the concept of a domain owner, the entity or entities that are authorized to make changes to a given DNS domain.
1397:
1111:
many. It was published in March 2015 on the
Independent Submission stream in the "Informational" (non-standard) category as RFC 7489.
762:
Rows are grouped by source IP and authentication results, passing just the count of each group. The leftmost result columns, labelled
49:
2056:
44:
protocol. It is designed to give email domain owners the ability to protect their domain from unauthorized use, commonly known as
1786:
Interoperability Issues between Domain-based
Message Authentication, Reporting, and Conformance (DMARC) and Indirect Email Flows
891:
Email message headers which include the sending host, email message ID, DKIM signature, and any other custom header information.
1790:
1702:
1602:
1365:
1254:
1107:
1060:
and DMARC reject using the Sender field on the non-technical basis that many user agents do not display this to the recipient.
1057:
385:
DMARC is capable of producing two separate types of reports. Aggregate reports are sent to the address specified following the
95:
1314:
Use of the Sender field by remailers is mentioned (in the context of DKIM, not DMARC) in sections B.1.4 and B.2.3 of RFC 4871.
1659:
1541:
330:
is the entry level policy. No special treatment is required by receivers, but enables a domain to receive feedback reports.
1740:
2422:
1828:
140:
field (also called "RFC5322.From") is "aligned" with other authenticated domain names. If either SPF (specified using the
909:, some of which may break SPF. This is one of the reasons why email forwarding can affect DMARC authentication results.
1676:
Once GZIP is registered as a MIME application type with IANA, the DMARC group will consider it as inclusion in the draft
1598:
Experimental Domain-Based
Message Authentication, Reporting, and Conformance (DMARC) Extension for Public Suffix Domains
1249:
162:
SPF checks that the IP address of the sending server is authorized by the owner of the domain that appears in the SMTP
2105:
1280:
1264:
80:
2178:
1923:
2240:
2022:
1846:
1115:
866:, resembles that of regular bounces in that they contain either a "message/rfc822" or a "text/rfc822-headers".
771:
SPF or DKIM, regardless of
Identifier Alignment. On the right side, SPF can appear at most twice, once for the
408:
2300:
1285:
1232:
917:
76:
1581:
1479:
863:
2131:
1977:
1428:
2327:
1270:
1904:
2405:
2244:
1850:
2014:
1948:
1804:
1716:
1616:
1475:
1379:
1194:
448:
403:). Multiple reporting addresses are valid and must each be in full URI format, separated by a comma.
41:
1450:
466:
84:
68:
2082:
362:
is being used to force mailing list managers to rewrite the From: field, as some don't do so when
48:. The purpose and primary outcome of implementing DMARC is to protect a domain from being used in
2427:
1182:
347:
153:
111:
27:
1779:
Franck Martin; Eliot Lear; Tim
Draegen; Elizabeth Zwicky; Kurt Andersen, eds. (September 2016).
1228:
840:
receivers are obviously free to apply the policy they like, it is just cool to let senders know,
427:, it looks for a confirming DNS record in the namespace administered by the target, like this:
1780:
1765:
1224:
20:
1633:
2179:"WG Action: Formed Domain-based Message Authentication, Reporting & Conformance (dmarc)"
1973:
1794:
1706:
1688:
1606:
1503:
1497:
1424:
1369:
1355:
1334:
1099:
906:
1692:
1429:"Domain-based Message Authentication, Reporting and Conformance (DMARC) [draft 01]"
1216:
1275:
1186:
1075:
2.1.16 was released with options to handle posters from a domain with the DMARC policy of
19:
This article is about an email validation system. For the telephony junction point, see
2223:"Businesses Can Help Stop Phishing and Protect their Brands Using Email Authentication"
350:
algorithm. The rest of the messages should undergo the lower policy; that is, none if
315:
for all domains. Regardless of intent, these mechanisms allow for greater flexibility.
167:
45:
816:
because a sender can choose to only apply the policy to a percentage of messages only,
2416:
1523:
1198:
128:
Setting up DMARC may improve the deliverability of messages from legitimate senders.
125:. Under DMARC a message can fail even if it passes SPF or DKIM but fails alignment.
83:(DKIM). It allows the administrative owner of a domain to publish a policy in their
72:
held within the DMARC record the email could be delivered, quarantined or rejected.
832:
the receiver heuristically determined that the message arrived from a mailing list,
61:
941:
One of the most popular and least intrusive workarounds consists of rewriting the
2127:
2010:
1807:
1784:
1719:
1696:
1619:
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1382:
1359:
1338:
1156:
1072:
1004:
994:
984:
974:
964:
424:
418:
401:
300:
57:
954:
operator). Those examples would result, respectively, in one of the following:
115:
1236:
1924:"Spam Resource: Run an email discussion list? Here's how to deal with DMARC"
1152:
2274:"Outlook.com increases security with support for DMARC and EV certificates"
1305:
INVALID is a top level domain reserved by RFC 2606 for this kind of usage.
1090:, thereby causing misbehavior in several mailing lists. A few days later,
1019:
header field. That way, the original meaning of those fields is reversed.
2060:
1202:
1190:
107:
report back to the sender's domain about messages that pass and/or fail.
53:
1098:. Those moves resulted in a significant amount of disruption, and those
2246:
Domain-based
Message Authentication, Reporting, and Conformance (DMARC)
1698:
Domain-based Message Authentication, Reporting, and Conformance (DMARC)
1361:
Domain-based Message Authentication, Reporting, and Conformance (DMARC)
1210:
1164:
1160:
1148:
1136:
1068:
A draft DMARC specification has been maintained since 30 January 2012.
98:'s published document RFC 7489, dated March 2015, as "Informational".
1799:
1711:
1611:
1508:
1374:
1206:
1176:
1168:
1140:
945:
header field. The original author's address can then be added to the
397:
430:
sender.example._report._dmarc.thirdparty.example IN TXT "v=DMARC1;"
2367:
2042:
1660:"What is the rationale for choosing ZIP for the aggregate reports?"
1172:
1144:
1083:
808:
while keeping the same bounce address, usually doesn't break DKIM,
443:
1879:
848:
if none of the above applies, a comment field allows to say more.
358:. If not specified, pct defaults to 100% of messages. The case
342:
asks receivers to outright reject messages that fail DMARC check.
1863:
1829:"How does email forwarding affect DMARC authentication results?"
1741:"I need to implement aggregate reports, what do they look like?"
1402:
787:
reflects the policy published actually applied to the messages,
148:) alignment checks pass, then the DMARC alignment test passes.
2101:
1995:
1132:
1091:
471:
439:
394:
34:
Domain-based Message Authentication, Reporting and Conformance
1220:
1103:
changing the “From” header to an address in its own domain.
389:. Forensic reports are emailed to the address following the
166:
command. (The email address in MAIL FROM is also called the
136:
DMARC operates by checking that the domain in the message's
75:
DMARC extends two existing email authentication mechanisms,
1398:"How we moved microsoft.com to a p=quarantine DMARC record"
197:
DMARC records are published in DNS with a subdomain label
220:
tags, separated by semicolons, similar to SPF and DKIM.
2259:
2157:
1409:
If that sounds like a lot of work, that's because it was
478:
DMARC rows of an aggregate record shown in tabular form
2057:"Yahoo email anti-spoofing policy breaks mailing lists"
2362:
2360:
2358:
2356:
2354:
2352:
2350:
2348:
2397:
2204:
1634:"RUA vs RUF - Different DMARC Report Types Explained"
1127:
The contributors of the DMARC specification include:
255:, percent of "bad" email on which to apply the policy
1595:
Scott Kitterman (26 July 2021). Tim Wicinski (ed.).
460:
example.com!example.org!1475712000!1475798400.xml.gz
377:allow tweaking the policy for specific subdomains.
216:The content of the TXT resource record consists of
1542:"Implementation Guidance: Email Domain Protection"
1260:Brand Indicators for Message Identification (BIMI)
299:"v=DMARC1;p=none;sp=quarantine;pct=100;rua=mailto:
185:tag aligns with the sender's domain stated in the
2249:. sec. E. I-D draft-kucherawy-dmarc-base-01.
1766:"The Ultimate Guide to DMARC Reporting in 2022"
1419:
1417:
949:field. Rewriting can range from just appending
824:the message arrived from a locally known source
393:tag. These mail addresses must be specified in
1873:
1871:
1219:(Founder/CEO Patrick R. Peterson), Cloudmark,
1027:field to attribute authorship to attachments.
323:First and foremost, there are three policies:
267:, requested interval between aggregate reports
2015:"Mitigating DMARC damage to third party mail"
1851:"Mitigating DMARC damage to third party mail"
869:Forensic Reports also contain the following:
261:, format for message-specific failure reports
8:
2301:"DMARC: a new tool to detect genuine emails"
2406:Mitigating DMARC damage to third party mail
2098:"AOL Mail updates DMARC policy to 'reject'"
110:These policies are published in the public
2328:"Introducing DMARC for Twitter.com emails"
1480:"Doing a tree walk rather than PSL lookup"
2228:. Federal Trade Commission. 3 March 2017.
1949:"How Threadable solved the DMARC problem"
1798:
1710:
1610:
1507:
1431:. IETF. Appendix A.3, Sender Header Field
1373:
1350:
1348:
1346:
279:, URI to send failure/forensic reports to
2096:Vishwanath Subramanian (22 April 2014).
1560:"User Guide for Cisco Domain Protection"
476:
2272:Vitaldevara, Krish (10 December 2012).
1905:"Upcoming changes for lists.debian.org"
1691:; Elizabeth Zwicky, eds. (March 2015).
1327:
1298:
1167:(163.com, 126.com, 188.com, yeah.net),
2239:Kucherawy, Murray; Zwicky, Elizabeth.
1451:"Bulk Senders Guidelines – Gmail Help"
373:and the newly added no-domain policy,
1524:"Tutorial: Recommended DMARC rollout"
905:There are several different types of
421:and wishes to report it. If it finds
144:field) or DKIM (specified using the
7:
2299:Martin, Franck (20 September 2012).
1582:""p=none" vs. "p=quarantine; pct=0""
1358:; Elizabeth Zwicky (18 March 2015).
87:records to specify how to check the
2404:The Anti Spam Research Group wiki:
885:SPF and DKIM authentication results
862:tag. Their format, an extension of
442:files, typically once per day. The
2055:Lucian Constantin (8 April 2014).
1580:Jonathan Kamens (9 October 2018).
1250:Authenticated Received Chain (ARC)
925:Turn off all message modifications
273:, URI to send aggregate reports to
14:
2326:Josh Aberant (21 February 2013).
2083:"Yahoo Statement on DMARC policy"
1094:also changed its DMARC policy to
50:business email compromise attacks
1396:Terry Zink (27 September 2016).
1878:Mark Sapiro (16 October 2013).
1255:Author Domain Signing Practices
369:Finally, the subdomain policy,
211:selector._domainkey.example.com
96:Internet Engineering Task Force
2185:(Mailing list). 11 August 2014
2081:Laura Atkins (12 April 2014).
1978:"Realistic responses to DMARC"
1215:Intermediaries & Vendors:
438:Aggregate Reports are sent as
306:organizational domain record.
122:
1:
1427:; Zwicky, E. (15 July 2013).
1036:authentication more fragile.
16:System to prevent email fraud
1086:changed its DMARC policy to
873:Source of Sending IP Address
1922:Al Iverson (9 April 2014).
243:, failure reporting options
2444:
1265:DomainKeys Identified Mail
81:DomainKeys Identified Mail
25:
18:
2305:LinkedIn Engineering Blog
755:
205:. Compare this to SPF at
1847:Anti-Spam Research Group
1116:Federal Trade Commission
956:
415:receives a mail message
223:The available tags are:
94:DMARC is defined in the
26:Not to be confused with
1286:Sender Policy Framework
1281:Mail servers with DMARC
879:Recipient email address
77:Sender Policy Framework
1233:Trusted Domain Project
1044:Making changes to the
864:Abuse Reporting Format
775:test and once for the
2368:"History – dmarc.org"
1271:E-mail authentication
991:JohnDoeviaMailingList
743:discusslist.example (
721:discusslist.example (
504:DKIM domain (result)
310:Step by step adoption
249:, policy (see below),
231:, DKIM alignment mode
2423:Email authentication
2132:"DMARC and ietf.org"
2085:. wordtothewise.com.
1976:(18 December 2016).
1478:(24 November 2020).
1195:Fidelity Investments
501:SPF domain (result)
400:format (e.g. mailto:
360:p=quarantine; pct=0;
237:, SPF alignment mode
42:email authentication
2158:"FAQ in DMARC wiki"
1998:commit's from field
1880:"Mailman and DMARC"
1793:. sec. 3.2.1.
1689:Murray S. Kucherawy
1114:In March 2017, the
678:forwarder.example (
479:
411:. For example, say
285:, subdomain policy,
2260:DMARC Contributors
2241:"Acknowledgements"
2130:(13 August 2016).
1693:"DMARC XML Schema"
1640:. 14 December 2023
1455:support.google.com
1183:American Greetings
882:Email subject line
876:From email address
477:
409:spam amplification
348:Bernoulli sampling
203:_dmarc.example.com
154:Public Suffix List
112:Domain Name System
28:dMarc Broadcasting
2108:on 13 August 2015
1835:. 6 January 2023.
1768:. 23 August 2019.
1548:. 12 August 2021.
1502:. sec. 6.3.
1100:mailbox providers
1071:In October 2013,
1031:Other workarounds
820:trusted forwarder
760:
759:
434:Aggregate reports
21:demarcation point
2435:
2401:
2400:
2398:Official website
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2104:. Archived from
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1800:10.17487/RFC7960
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1375:10.17487/RFC7489
1356:Murray Kucherawy
1352:
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907:email forwarding
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853:Forensic reports
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413:receiver.example
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354:, quarantine if
353:
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123:§ Alignment
90:
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2013:(31 May 2014).
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1276:Certified email
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1187:Bank of America
1125:
1095:
1087:
1082:In April 2014,
1076:
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1011:The last line,
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67:Once the DMARC
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5:
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2390:External links
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1984:(Mailing list)
1965:
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1864:dmarc.org wiki
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1569:. 25 May 2021.
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209:, and DKIM at
201:, for example
194:
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189:header field.
168:bounce address
133:
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114:(DNS) as text
103:
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46:email spoofing
15:
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1425:Kucherawy, M.
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933:
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924:
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918:Mailing lists
913:Mailing lists
912:
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896:Compatibility
895:
890:
888:Received time
887:
884:
881:
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296:For example:
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2377:23 September
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2335:. Retrieved
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2278:Outlook Blog
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1301:
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1123:Contributors
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1067:
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1043:
1040:Sender field
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1021:
1010:
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836:local policy
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828:mailing list
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792:
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784:
782:
773:Return-Path:
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525:
498:Header from
464:
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451:(used to be
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352:p=quarantine
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109:
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66:
64:activities.
62:cyber threat
37:
33:
32:
2332:twitter.com
2284:12 December
2280:. Microsoft
2205:"DMARC FAQ"
2128:John Levine
2045:, dmarc.org
2011:John Levine
1833:progist.net
1644:14 December
1638:Progist.net
1546:cyber.gc.ca
1157:Outlook.com
1131:Receivers:
1073:GNU Mailman
812:sampled out
785:disposition
489:Disposition
449:compression
423:ruf=mailto:
207:example.com
116:TXT records
58:email scams
2417:Categories
2307:. Linkedin
2189:10 October
2142:10 October
1528:google.com
1484:dmarc-ietf
1322:References
1229:ReturnPath
901:Forwarders
793:quarantine
691:192.0.2.82
626:192.0.2.28
334:quarantine
291:, version,
218:name=value
193:DNS record
79:(SPF) and
60:and other
2428:Anti-spam
2372:dmarc.org
2311:17 August
2209:dmarc.org
2112:13 August
2043:"History"
1889:13 August
1745:DMARC.org
1664:DMARC.org
1567:cisco.com
1181:Senders:
1153:Microsoft
1013:Reply-To:
999:Reply-To:
947:Reply-To:
937:rewriting
804:forwarded
569:192.0.2.1
512:192.0.2.1
483:Source IP
164:MAIL FROM
132:Alignment
2337:10 April
2066:15 April
2061:PC World
1988:14 March
1933:18 April
1884:list.org
1813:14 March
1499:RFC 7489
1460:24 April
1244:See also
1237:ProDMARC
1225:Red Sift
1203:LinkedIn
1191:Facebook
1096:p=reject
1088:p=reject
1077:p=reject
951:.INVALID
734:✗
710:✗
701:✗
658:✗
636:✗
612:✗
588:✗
467:relation
356:p=reject
102:Overview
54:phishing
40:) is an
2163:15 July
1781:"Alias"
1725:3 March
1670:3 April
1211:Twitter
1165:Netease
1161:Hotmail
1149:Mail.Ru
1137:Comcast
1064:History
1051:Sender:
1001:JohnDoe
981:JohnDoe
971:JohnDoe
961:JohnDoe
621:
564:
507:
444:subject
381:Reports
56:email,
2028:1 June
1958:21 May
1750:26 May
1666:. 2012
1435:24 May
1337:
1267:(DKIM)
1207:PayPal
1177:Yandex
1169:XS4ALL
1141:Google
797:reject
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712:
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486:Count
417:From:
398:mailto
364:p=none
340:reject
319:Policy
199:_dmarc
2262:(PDF)
2226:(PDF)
1563:(PDF)
1293:Notes
1288:(SPF)
1217:Agari
1173:Yahoo
1145:Gmail
1084:Yahoo
1056:Both
1046:From:
1025:From:
1017:From:
989:From:
979:From:
969:From:
959:From:
943:From:
935:From:
844:other
795:, or
495:DKIM
229:adkim
187:From:
146:adkim
138:From:
89:From:
38:DMARC
2379:2020
2339:2014
2313:2013
2286:2012
2191:2016
2165:2020
2144:2016
2136:IETF
2114:2015
2068:2014
2030:2014
2023:ASRG
2019:wiki
1990:2017
1960:2016
1935:2014
1891:2015
1815:2017
1808:7960
1791:IETF
1752:2016
1727:2019
1720:7489
1703:IETF
1672:2019
1646:2023
1620:9091
1603:IETF
1462:2015
1437:2016
1405:blog
1403:MSDN
1383:7489
1366:IETF
1339:7489
1108:IETF
1058:ADSP
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1003:<
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783:The
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768:DKIM
766:and
756:...
749:Pass
738:Fail
727:Pass
714:Fail
705:Fail
697:none
684:Pass
673:Pass
662:Fail
649:Pass
640:Fail
632:none
616:Fail
605:Pass
592:Fail
583:Pass
575:none
559:Pass
548:Pass
535:Pass
526:Pass
518:none
453:.zip
328:none
235:aspf
142:aspf
2102:AOL
1996:git
1805:RFC
1795:doi
1717:RFC
1707:doi
1617:RFC
1607:doi
1504:doi
1380:RFC
1370:doi
1335:RFC
1163:),
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1133:AOL
1106:An
1092:AOL
764:SPF
694:21
629:42
515:12
492:SPF
455:).
440:XML
395:URI
391:ruf
387:rua
375:np=
371:sp=
302:;"
277:ruf
271:rua
253:pct
85:DNS
69:DNS
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2347:^
2330:.
2303:.
2276:.
2243:.
2207:.
2181:.
2134:.
2100:.
2059:.
2021:.
2017:.
1992:.
1980:.
1951:.
1926:.
1907:.
1882:.
1870:^
1849:.
1831:.
1803:.
1789:.
1783:.
1743:.
1715:.
1701:.
1695:.
1674:.
1662:.
1636:.
1615:.
1605:.
1601:.
1565:.
1544:.
1526:.
1482:.
1453:.
1416:^
1407:.
1400:.
1378:.
1368:.
1364:.
1345:^
1239:,
1235:,
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860:fo
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751:)
740:)
729:)
686:)
675:)
664:)
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