Email authentication standards are maturing and now, the SPF protocol also has some new elements to add to its list; we are talking about the SPF flattening technique and SPF macros. These relatively newer features offer an alternative approach to address the complexities linked with email authentication and deliverability.
This blog discusses SPF flattening and SPF macros, comparing their features, benefits, and considerations to help you understand which one is needed for your business domains.
Understanding SPF
SPF is a widely adopted email authentication protocol that lets domain administrators publish a list of mail servers and IP addresses that the company officially allows to be used for sending emails on its behalf. All these sources are published in a TXT-format record called SPF record.
Upon receiving an email, the recipient’s email server queries the sender’s domain’s SPF record to verify if the sending server is actually part of the authorized list. If the sender’s server is mentioned in the list, the email is considered legitimate, otherwise, it’s deemed illegitimate.
There are two mechanisms to deal with illegitimate emails- SPF Softfail and SPF Hardfail, and you can set your SPF record to either of the mechanisms. SPF Softfail instructs recipients’ servers to flag suspicious emails and place them in spam folders. SPF Hardfail commands recipients’ servers to reject suspicious emails, leaving no possibility of phishing.
Introducing SPF Flattening
SPF flattening simplifies the management of SPF records, especially for organizations with complex email ecosystems, as their records are highly likely to reach the maximum limit of 10 DNS lookups. Reaching this limit triggers SPF Permerror, causing the invalidation of SPF TXT records.
SPF flattening simplifies your DNS records by replacing complex data with a single record, allowing you to easily authenticate new users and domains with a single click.
We at AutoSPF offer SPF flattening service while ensuring your data is safe, and you comply with new industry compliance requirements. We also work with your enterprise’s existing access controls for additional security.
Our Features
- Automated SPF Flattening for up to 5 domains
- Unlimited Emails (no monthly cap, no meter)
- 99.99% DNS availability SLA
- Teams & User Management
- Enterprise SSO
- Audit Logs & Reports
- SAML
- SOC-2 Type II compliance
- Vendor Security Questionnaire
- Subdomain Reporting
- DMARC Reporting
- White-glove onboarding
Image sourced from descope.com
Exploring SPF Macros
While SPF flattening simplifies SPF management and keeps your SPF record within the lookup limit, SPF macros offer a different approach for dealing with the limitations of SPF records. SPF macros lets domain administrators define reusable macros within their SPF records, enabling dynamic inclusions of additional domains or IP addresses based on predefined rules.
For example, organizations leveraging multiple third-party services for email delivery can use SPF macros to include dynamically generated SPF records from these services within their main SPF record. This dynamic inclusion ensures that authorized third-party services are accounted for in the SPF authentication process without the need for manual updates to the SPF record whenever services change.
The Right Approach for Your Business Domain
When deciding between these two techniques of SPF, you must consider various factors, including your email infrastructure complexity, overhead maintenance expense and resource demand, compatibility with existing systems, etc. Here are some key considerations-
1. Infrastructural Complexity
If your email infrastructure is diverse and includes several mail servers and third-party services, it may be better to opt for SPF flattening to simplify SPF record management.
2. Dynamic Services
If your organization relies heavily on third-party services with dynamic IP addresses or domains, SPF macros may offer more flexibility by dynamically including these services in the SPF record.
3. Compatibility
Ensure that the chosen approach is compatible and aligns well with your company’s email infrastructure, including email servers, spam filters, and recipient’s email servers.
4. Maintenance Overhead
Consider the ease of updating and maintaining SPF records. SPF flattening reduces the number of records that need updating, while SPF macros offer dynamic inclusion but may require additional configuration.
5. Scalability
Evaluate how each approach stands with your organization’s growth and evolving email infrastructure needs. If the chosen approach hinders your future goals, rethink and plan accordingly.
Wrapping Up!
SPF flattening and SPF macros offer alternative approaches to handling the shortcomings of SPF records. They are more useful for organizations with intricate email ecosystems. Ultimately, selecting the right approach is crucial to enhancing email security and ensuring the reliable delivery of legitimate emails to recipients’ inboxes.
