What are common confusions in email authentication and DMARC reporting?

Summary

Common confusions in email authentication and DMARC reporting span technical implementations, policy understanding, and ongoing maintenance. Many struggle with the complexity of setting up DMARC policies and interpreting DMARC reports, particularly the aggregate and forensic types. Specific technical issues include exceeding SPF's 10 DNS lookup limit, improper DKIM key rotation, and DNS propagation delays. Misunderstandings about the 'p=none' DMARC policy, the differences between SPF and DKIM, the importance of alignment, and the need for continuous monitoring all contribute to confusion. Incorrect DMARC record syntax and overlooking SPF's limitations with email forwarding further complicate matters. Properly implementing and maintaining SPF, DKIM, and DMARC is essential but often misconfigured.

Key findings

  • Setup & Policy Complexity: DMARC setup is complex with varying policies (none, quarantine, reject) and implications.
  • Reporting Challenges: DMARC aggregate and forensic reports are hard to interpret due to their complex format.
  • SPF Limitations: SPF breaks with email forwarding as the forwarding server isn't authorized.
  • DKIM Rotation Errors: Forgetting to update DNS after DKIM key rotation is a common error.
  • p=none Misinterpretation: The 'p=none' DMARC policy is often mistaken for providing protection.
  • SPF vs. DKIM Confusion: SPF and DKIM functionalities are frequently confused (server vs. content authentication).
  • Alignment Neglect: Importance of DMARC alignment for authentication is frequently overlooked.
  • Record Syntax Errors: DMARC record syntax errors prevent the correct implementation of DMARC.
  • Ongoing Maintenance is Essential: Ongoing monitoring and adjustments are needed with DMARC.
  • DNS Propagation Issues: DNS propagation times for SPF, DKIM, and DMARC records cause confusion and delays.

Key considerations

  • Choose appropriate DMARC Policies: Understand the implications of DMARC policies before implementation.
  • Simplify Report Analysis: Utilize tools to assist in parsing and analyzing DMARC reports effectively.
  • Manage SPF for Forwarding: Address SPF issues with forwarding using SRS or similar mechanisms.
  • Automate DKIM Updates: Implement procedures for automatically updating DNS records when DKIM keys are rotated.
  • Move beyond p=none: Implement policies beyond P=none in DMARC records.
  • Establish monitoring processes: Implement processes for regularly monitoring DMARC performance and adjusting configurations as needed.
  • Validate DMARC Syntax: Ensure that DMARC record syntax is correct.
  • Plan for Delays: Plan for delays after setting up your SPF, DKIM and DMARC records to ensure proper DNS propogation.
  • Stay Updated: Continuously monitor and adjust email authentication based on infrastructure and changing threats.

What email marketers say
11Marketer opinions

Common confusions in email authentication and DMARC reporting stem from several areas. Many users struggle with the intricacies of setting up DMARC policies and interpreting DMARC aggregate and forensic reports. Technical aspects like SPF's limitations with forwarding, DKIM key rotation, and DNS propagation times also cause confusion. Furthermore, differentiating between SPF and DKIM, understanding the importance of alignment for DMARC, and recognizing that DMARC setup is an ongoing process, not a one-time fix, are frequent points of misunderstanding. Misinterpreting DMARC failure reasons and the implications of not implementing DMARC correctly on deliverability compound these issues.

Key opinions

  • DMARC Setup Complexity: Setting up DMARC policies (none, quarantine, reject) and understanding their implications is complex.
  • Report Interpretation: Many users are confused by DMARC aggregate and forensic reports, making it challenging to identify authentication failures and spoofing attempts.
  • SPF Limitations: SPF breaks with email forwarding because the forwarding server isn't authorized, leading to authentication failures.
  • SPF/DKIM Confusion: Users often confuse SPF and DKIM, not realizing that SPF authenticates the sending server while DKIM authenticates the message content.
  • Alignment Importance: Understanding the concept of alignment and its necessity for DMARC pass is often overlooked.
  • Ongoing Monitoring: DMARC setup is an ongoing process requiring continuous monitoring and adjustments.
  • DNS Propagation: DNS propagation times cause confusion after setting up SPF, DKIM, and DMARC records. Changes aren't instant and updates can take up to 48 hours to apply.

Key considerations

  • Understand DMARC Policies: Clearly understand the implications of 'none,' 'quarantine,' and 'reject' DMARC policies before implementing them.
  • Analyze DMARC Reports: Develop a strategy for parsing and analyzing DMARC aggregate and forensic reports to identify and address authentication issues.
  • Address SPF Issues: Implement solutions to handle SPF failures with email forwarding, such as using SRS (Sender Rewriting Scheme).
  • Implement Both SPF and DKIM: Ensure both SPF and DKIM are correctly implemented for robust email authentication.
  • Monitor DMARC Compliance: Regularly monitor DMARC compliance and adjust configurations as needed to maintain optimal deliverability.
  • DNS Propagation: Consider DNS propagation times of up to 48 hours after setting up SPF, DKIM and DMARC to ensure records have been properly implemented.
Marketer view

Email marketer from MXToolbox explains that interpreting the reasons for DMARC failures, such as SPF SoftFail or DKIM signature mismatch, is a common point of confusion. Determining the root cause requires careful analysis of the reports.

December 2021 - MXToolbox Blog
Marketer view

Email marketer from StackOverflow shares that users often struggle with setting up separate DMARC records for subdomains and delegating sending authority correctly.

April 2021 - StackOverflow
Marketer view

Email marketer from Email Geeks explains that while an email may pass authentication, it likely won't pass alignment, which is required for DMARC pass.

June 2023 - Email Geeks
Marketer view

Email marketer from LinkedIn shares that not implementing DMARC correctly or misinterpreting reports can lead to deliverability issues, such as emails landing in the spam folder or being blocked altogether.

April 2022 - LinkedIn
Marketer view

Email marketer from EmailVendorSelection explains that after setting up SPF, DKIM and DMARC is that DNS propagation times are a common source of confusion. The updates aren't instant so changes can take up to 48 hours to update correctly.

February 2022 - EmailVendorSelection
Marketer view

Email marketer from Mailhardener Blog explains that a common confusion is the complexity of setting up DMARC, especially understanding the different policies (none, quarantine, reject) and their implications.

January 2023 - Mailhardener Blog
Marketer view

Email marketer from EasyDMARC Blog shares that many users are confused by DMARC aggregate reports and forensic reports. Understanding how to interpret these reports to identify authentication failures and potential spoofing attempts is a challenge.

August 2022 - EasyDMARC Blog
Marketer view

Email marketer from Postmark explains that many users confuse SPF and DKIM, not understanding that SPF authenticates the sending server, while DKIM authenticates the message content. Both are needed for robust authentication.

January 2024 - Postmark Blog
Marketer view

Email marketer from Email Geeks shares that headers can be confusing for someone not in the email world.

May 2021 - Email Geeks
Marketer view

Email marketer from Reddit explains that a common issue is when emails are forwarded, SPF breaks because the forwarding server isn't authorized in the original SPF record. This leads to authentication failures.

July 2021 - Reddit
Marketer view

Email marketer from Email Geeks thinks the writer of the KB is conflating “pass” and “align”.

September 2021 - Email Geeks

What the experts say
3Expert opinions

The experts highlight several points of confusion related to email authentication and DMARC reporting. DMARC aggregate reports are difficult to understand due to their complex XML format, making it challenging to extract actionable information about authentication failures. Additionally, there's a misconception that DMARC setup is a one-time task, when in reality, ongoing monitoring and adjustments are crucial as email infrastructure and sending practices change. The DMARC reporting itself is confusing and does not make much sense.

Key opinions

  • Reporting Complexity: DMARC reporting itself is confusing.
  • Report Interpretation Difficulty: DMARC aggregate reports, being large XML files, are hard to parse and analyze for meaningful data.
  • Ongoing Maintenance Required: DMARC setup isn't a one-time task; it requires continuous monitoring and adjustments.

Key considerations

  • Invest in Report Parsing Tools: Consider using tools or services that simplify the parsing and analysis of DMARC aggregate reports.
  • Establish Monitoring Processes: Implement processes for regularly monitoring DMARC performance and adjusting configurations as needed.
  • Stay Updated on Email Infrastructure: Keep abreast of changes in email infrastructure and sending practices to ensure DMARC remains effective.
Expert view

Expert from Email Geeks states that the reporting is confusing. Nothing in that “evaluated” section makes much sense.

August 2024 - Email Geeks
Expert view

Expert from Word to the Wise explains that a common confusion is thinking DMARC is a one-time setup. Ongoing monitoring and adjustments are needed as email infrastructure and sending practices evolve. For example: Adjusting your SPF records or DNS records.

August 2023 - Word to the Wise
Expert view

Expert from Spam Resource explains that understanding DMARC aggregate reports is difficult because they are large XML files that require parsing and analysis to extract useful information about authentication failures and potential abuse. Many struggle to interpret these reports effectively.

December 2021 - Spam Resource

What the documentation says
5Technical articles

Documentation highlights several technical misunderstandings related to email authentication and DMARC reporting. A frequent issue is exceeding SPF's 10 DNS lookup limit, which can cause authentication failures. Another common mistake is failing to update DNS records after rotating DKIM keys. Additionally, many misunderstand the 'p=none' DMARC policy, believing it provides protection when it only gathers data. Incorrect DMARC record syntax, such as incorrect tag values or missing semicolons, also leads to problems. Finally, the documentation states that implementing all three of SPF, DKIM and DMARC is essential but commonly incorrectly configured or managed.

Key findings

  • SPF Lookup Limit: Exceeding SPF's 10 DNS lookup limit can cause authentication failures.
  • DKIM Key Rotation: Forgetting to update DNS records after rotating DKIM keys is a common mistake.
  • DMARC p=none Misunderstanding: Many believe the 'p=none' DMARC policy provides protection when it only gathers data.
  • DMARC Syntax Errors: Incorrect syntax in DMARC records, such as incorrect tag values or missing semicolons, can cause the record to be ignored.
  • Incorrect Configuration: Implementing all three of SPF, DKIM and DMARC is essential but commonly incorrectly configured or managed.

Key considerations

  • Optimize SPF Records: Ensure SPF records are optimized to stay within the 10 DNS lookup limit.
  • Automate DKIM Key Rotation: Implement a process for automatically updating DNS records after DKIM key rotation.
  • Choose Appropriate DMARC Policy: Select an appropriate DMARC policy ('quarantine' or 'reject') once ready to actively protect against spoofing.
  • Validate DMARC Syntax: Carefully validate the syntax of DMARC records to avoid errors.
  • Double check all implementations: Ensure that you have thoroughly checked the implementation of your SPF, DKIM and DMARC records to ensure they have been properly configured.
Technical article

Documentation from Google explains that a frequent misunderstanding involves SPF's 10 DNS lookup limit. Exceeding this limit can cause SPF checks to fail, impacting deliverability.

August 2021 - Google
Technical article

Documentation from RFC Editor explains that a frequent source of confusion is the correct syntax for DMARC records. Incorrect tag values or missing semicolons can cause the record to be ignored.

March 2024 - RFC Editor
Technical article

Documentation from DMARC.org explains that many people misunderstand the 'p=none' policy, thinking it provides protection. In reality, it only gathers data and doesn't actively reject or quarantine emails.

March 2022 - DMARC.org
Technical article

Documentation from Microsoft explains that a common confusion is how to properly rotate DKIM keys. Forgetting to update the DNS record with the new public key after generating a new key pair is a frequent mistake.

May 2021 - Microsoft Docs
Technical article

Documentation from AuthSMTP, explains that implementing all three of SPF, DKIM and DMARC is essential but commonly incorrectly configured or managed. The site goes on to explain some common issues and configurations that lead to these misconfigurations.

October 2024 - AuthSMTP