Summary
Enforcing DMARC policies for a bulk sender starting with 'p=none' involves a phased approach focused on thorough monitoring, authentication, and strategic domain management. Initially, implement a DMARC record in your DNS and diligently monitor DMARC reports to identify all legitimate sending sources, including third-party services and potential 'shadow IT'. Ensure proper SPF and DKIM configuration for these sources, paying close attention to DMARC alignment. Consider separating email streams (transactional vs. marketing) using subdomains to simplify management and avoid implementing 'p=reject' at the apex domain prematurely. A gradual transition to stricter policies (p=quarantine or p=reject) is crucial, allowing sufficient time for monitoring and issue resolution at each stage. For multi-sender environments, coordinate DMARC implementation across all ESPs. Regularly validate your DMARC record for syntax errors and leverage reporting tools to proactively address authentication failures, safeguarding your brand against spoofing and phishing attacks.
Key findings
- Comprehensive Monitoring: Thoroughly monitor DMARC reports to identify all sending sources and authentication issues.
- Authentication Imperative: Ensure all legitimate sending sources are properly authenticated using SPF and DKIM.
- Phased Enforcement Strategy: Implement DMARC policies gradually, starting with 'p=none' and progressing to stricter policies.
- Subdomain Segmentation: Utilize subdomains to manage email streams and simplify DMARC enforcement.
- Apex Domain Caution: Avoid immediate 'p=reject' at the apex domain to prevent disruption of legitimate email.
Key considerations
- Proactive Report Analysis: Regularly analyze DMARC reports to identify trends and address authentication failures promptly.
- Third-Party Coordination: Coordinate DMARC implementation across all third-party email sending services and ESPs.
- Testing and Validation: Test and validate DMARC records for correct syntax and configuration.
- Gradual Transition Timeline: Allow sufficient time for monitoring and issue resolution at each DMARC policy level.
- Shadow IT Discovery: Proactively identify and address potential 'shadow IT' email sending sources within the organization.
What email marketers say
9 marketer opinions
Enforcing DMARC policies for a bulk sender with 'p=none' requires a phased approach. Initially, focus on identifying and authenticating all legitimate sending sources using SPF and DKIM. Closely monitor DMARC reports to detect authentication failures and unexpected sending sources. Using subdomains to separate email streams (e.g., transactional vs. marketing) simplifies DMARC management. Coordinate DMARC implementation across all email service providers (ESPs). Enforcing stricter DMARC policies (p=quarantine or p=reject) helps protect your brand against spoofing and phishing attacks, maintaining customer trust. A gradual transition, with monitoring at each stage, is crucial to avoid disrupting legitimate email delivery.
Key opinions
- Authentication: Ensure all legitimate sending sources are properly authenticated with SPF and DKIM.
- Monitoring: Closely monitor DMARC reports to identify authentication failures and unauthorized sources.
- Phased Approach: Implement DMARC policies in stages, starting with 'p=none' and gradually moving to stricter policies.
- Subdomain Usage: Utilize subdomains to separate email streams for easier DMARC management.
- Brand Protection: Enforcing strict DMARC policies protects your brand against email spoofing and phishing attacks.
Key considerations
- Report Analysis: Regularly analyze DMARC reports to understand your email ecosystem and address authentication issues.
- Third-Party Services: Coordinate DMARC implementation with all third-party email sending services.
- Transition Time: Allow sufficient time (e.g., months) for monitoring at each DMARC policy level before transitioning to a stricter policy.
- SPF/DKIM Configuration: Verify that SPF and DKIM records are correctly configured for all sending domains and subdomains.
- Impact Assessment: Assess the potential impact of stricter DMARC policies on legitimate email delivery before enforcement.
Marketer view
Email marketer from Agari shares that DMARC is vital for protecting your brand against email spoofing and phishing attacks. Enforcing a strict DMARC policy ensures that unauthorized emails are blocked or quarantined, preventing malicious actors from using your domain to send fraudulent emails. This helps maintain customer trust and protects your brand reputation.
16 Aug 2023 - Agari (Proofpoint)
Marketer view
Email marketer from Valimail shares that DMARC enforcement should be approached in stages. Starting with 'p=none' allows you to gather data and identify legitimate sending sources. Before moving to 'p=quarantine' or 'p=reject', ensure all authorized sending sources are properly authenticated (SPF, DKIM). Monitor DMARC reports to identify and address any authentication failures before enforcing stricter policies to avoid disrupting legitimate email flow.
1 Jul 2022 - Valimail
What the experts say
8 expert opinions
Enforcing DMARC policies for bulk senders with a 'p=none' setting involves several key steps and considerations. Initial focus should be on thorough monitoring of DMARC reports to identify all legitimate sending sources, ensuring they are properly authenticated with SPF and DKIM. Investigate any unexpected or 'illegitimate' sources, as these could be legitimate 'shadow IT' setups. Consider treating marketing and transactional emails separately using subdomains, particularly when sending from an apex domain. Avoid immediately implementing 'p=reject' at the apex domain, as this can disrupt business email communications. Use a reliable reporting service and consistently review reports for issues. Test DMARC records and review results before moving towards enforcement.
Key opinions
- Source Identification: Identify all legitimate sending sources, including potential 'shadow IT' setups.
- Authentication is Key: Ensure all identified sources are properly authenticated with SPF and DKIM.
- Subdomain Separation: Consider using subdomains to separate marketing and transactional email streams.
- Monitoring is Critical: Diligently monitor DMARC reports to identify issues before implementing stricter policies.
- Apex Domain Caution: Avoid immediately implementing 'p=reject' at the apex domain due to potential disruption.
Key considerations
- Reporting Service: Use a reliable DMARC reporting service.
- Regular Review: Consistently review DMARC reports for issues.
- Testing is essential: Testing DMARC records is a must before moving to stricter configurations.
- Phased Enforcement: Enforce policies gradually after thorough monitoring at 'p=none'.
- Shadow IT Awareness: Be aware of and investigate potential 'shadow IT' email sending sources.
Expert view
Expert from Email Geeks explains that p=quarantine and p=reject are basically the same, as far as most things are concerned and mail that’s not authenticated, or which has lost authentication in transit, doesn’t get delivered.
18 Aug 2023 - Email Geeks
Expert view
Expert from Email Geeks shares when "you thought it was illegitimate but it was actually legit use, some service or server set up by somebody in your company without telling everybody else," it's called shadow IT, like, if an HR manager outsourced resume/applicant management to a service and that service sends mails but nobody told you about it and nobody thought to set up DKIM.
9 Dec 2022 - Email Geeks
What the documentation says
5 technical articles
Enforcing DMARC policies for a bulk sender, starting with 'p=none', involves several steps outlined in technical documentation. The initial 'p=none' policy allows for data collection and monitoring of email traffic without impacting delivery. DMARC records should be published in your domain's DNS, specifying how email receivers should handle messages failing DMARC checks. It is crucial to review generated reports to identify authentication issues with legitimate sources, ensuring proper SPF and DKIM configuration. Gradual transitions to 'p=quarantine' and 'p=reject' should occur after verifying that all authorized sources are correctly authenticated. DMARC alignment, ensuring the 'From:' header domain matches the SPF or DKIM domain, is critical for proper function. Using a DMARC record checker is advised to validate the syntax and configuration of your DMARC record.
Key findings
- Monitoring Start: Begin with a 'p=none' policy for initial data collection and monitoring.
- DNS Record Publication: Publish a DMARC record in your domain's DNS.
- Authentication Verification: Verify SPF and DKIM configuration for legitimate email sources.
- Gradual Transition: Move to stricter policies ('p=quarantine', 'p=reject') gradually after verification.
- DMARC Alignment: Ensure proper DMARC alignment between 'From:' header and SPF/DKIM domains.
Key considerations
- Report Review: Regularly review DMARC reports to identify and correct authentication issues.
- Record Validation: Use a DMARC record checker tool to validate record syntax and configuration.
- DMARC Configuration: Configure DMARC record to specify handling of failed messages.
- SPF/DKIM Setup: Ensure correct setup of SPF and DKIM for all sending sources.
- Phased Implementation: Implement DMARC policies in a phased approach.
Technical article
Documentation from DMARC.org explains that the 'p=none' policy allows you to collect data without impacting email delivery. Before enforcing, ensure that your email streams are properly authenticated and aligned with DMARC requirements. After the monitoring phase, transition to 'p=quarantine' to send non-compliant emails to spam folders, and eventually to 'p=reject' to block them entirely. Regularly review aggregate reports to identify and correct any authentication issues.
12 Feb 2025 - DMARC.org
Technical article
Documentation from AuthSMTP shares that you should use a DMARC record checker tool to validate that your record is syntactically correct and properly configured. This tool can identify any errors in your record that may cause it to be ineffective. Make sure the syntax follows the rules.
1 Mar 2025 - AuthSMTP
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