What are wildcard, DKIM, and DMARC best practices?

Email marketer from EasyDMARC shares that implementing DMARC enhances email deliverability, protects brand reputation, and prevents phishing attacks. They emphasize the importance of continuous monitoring and adjusting DMARC policies to optimize email authentication.

Email marketer from Proofpoint explains that DKIM and DMARC are essential for protecting your brand from email spoofing and phishing attacks. DKIM authenticates the sender's domain, while DMARC builds upon DKIM and SPF to provide instructions to email receivers on how to handle unauthenticated emails.

Email marketer from Mimecast explains that DMARC reporting is crucial for understanding your email authentication ecosystem. They recommend analyzing DMARC reports to identify and address any issues with email deliverability.

Email marketer from Mailchimp shares that to set up DMARC, you need to publish a DMARC record in your DNS settings. This record tells email providers what to do with messages that fail authentication checks. They also recommend starting with a 'p=none' policy to monitor results before enforcing stricter policies.

Email marketer from Reddit explains that using wildcard DNS records can simplify the creation of multiple subdomains but advises caution due to potential security risks. They recommend carefully planning which subdomains should be covered by the wildcard record.

Email marketer from Agari shares that regular DKIM key rotation is a best practice to mitigate the risk of key compromise. Rotating DKIM keys ensures that even if a key is compromised, the impact is limited to the period before the rotation.

Email marketer from ReturnPath explains that whilst not DNS wildcard records, wildcard TLS certificates also present similar challenges around security and control. Use with caution and consider all subdomains it may impact.

Email marketer from SparkPost explains that correctly configuring SPF (Sender Policy Framework) and DKIM is crucial for email deliverability. They recommend using a dedicated sending domain and regularly checking SPF and DKIM records for accuracy.

Expert from Word to the Wise explains the relationship between wildcard DNS records and DKIM/DMARC, noting that wildcard DNS can simplify setup but can also lead to unexpected authentication results if not properly managed. Atkins recommends careful planning and monitoring when using wildcard DNS with DKIM/DMARC.

Expert from Email Geeks shares a blog post regarding wildcards, DKIM, and DMARC.

Expert from Word to the Wise shares the setup of a stunt DNS server to help with DMARC. The stunt DNS server will only answer DNS queries for subdomains that exist on the sending domain. This simplifies the DMARC setup when the subdomains are dynamically created.

Expert from Email Geeks shares a followup blog post regarding stunt DNS servers, including the software and config to deploy one.

Documentation from Microsoft shares that SPF, DKIM, and DMARC work together to provide anti-spoofing protection. Microsoft recommends using all three methods to ensure the best possible email security and deliverability.

Documentation from Google explains that DKIM (DomainKeys Identified Mail) is an email authentication method that helps prevent spammers from forging your domain's email address. Best practices include generating a 2048-bit key, regularly rotating keys, and publishing the DKIM record to your DNS.

Documentation from Cloudflare explains that wildcard DNS records are used to match requests for non-existent domain names. Best practices include using them to simplify DNS configuration for subdomains but carefully considering security implications to avoid unintended matches.

Documentation from IETF explains that RFC 7489 defines the DMARC standard. The document provides detailed technical specifications for implementing DMARC, including the syntax and semantics of DMARC records.

Documentation from DMARC.org explains that implementing DMARC (Domain-based Message Authentication, Reporting & Conformance) involves setting up a DMARC policy to instruct recipient mail servers on how to handle emails that fail DKIM and SPF checks. Best practices include starting with a policy of 'p=none' to monitor email streams, then gradually moving to 'p=quarantine' and finally 'p=reject' as confidence increases.