To understand what SPF flattening is, we should first understand the role of SPF itself. Sender Policy Framework (SPF) record refers to the type of DNS record that enables domain owners to prevent email fraud. An SPF record helps specify legitimate, authorized mail servers and domains that can send emails from a given address and tell them apart from unauthorized ones. The email server that receives the email checks the SPF record to confirm whether the sending IP address belongs to its list of legitimate IP addresses and lets it enter the inbox if the IP address is in the list. Otherwise, the email will fall into spam.
10 Lookups Limit. Why Care?
It is important to always keep the SPF record within the limits of 10 lookups so that there is not much load on the DNS servers. If your SPF record exceeds the maximum limit of 10 lookups, your server might take a longer time to process the email. In this case, an email message might fail SPF inspection, which can result in deliverability issues and significantly hurt your domain reputation. Additionally, customers might miss important emails containing information and updates about your business (e.g. location change), thereby impacting your sales and profits.
This is when SPF flattening comes into place. It enables you to simplify and optimize an SPF record, thereby reducing the amount of DNS lookups that are required to check an SPF record. With SPF flattening, you can turn multiple nested SPF record domains into a flat list of IP addresses. SPF flattening works by replacing all the “include” parts in the original SPF record with the real IP addresses and domains found in those included records. This process turns a complex, nested SPF setup into a simple, flat list of allowed senders.
What Are the Main Advantages of SPF Flattening?
SPF flattening involves an optimization of SPF records which in turn brings numerous benefits.
1. Enhanced Compliance
Flattening ensures your SPF records are simplified enough to comply with the maximum DNS lookup limit requirement. This in turn helps adhere to email authentication RFC requirements that are the core output of the IETF. This makes your domain more credible for email-receiving mail servers, increasing open rates.
2. An Email Deliverability Boost
Did you know that surpassing the SPF lookup limit can lead to a situation where your emails are flagged or rejected by the recipient’s mail server? As a result, your email deliverability might suffer significantly and prevent your important messages from getting to the intended recipient. Therefore, keeping your SPF record in line with the regulations with the help of SPF flattening will help you boost your email deliverability rate and keep your communications with your audience smooth and trustworthy.
3. Goodbye, Email Spoofing
If you effectively pair SPF with DMARC for email security and simultaneously optimize your SPF records with the help of flattening, you can significantly reduce spoofing and phishing and the likelihood of DMARC failures.
Manual vs Automated SPF Flattening
We do not recommend users do SPF flattening manually since it may cause numerous problems that will affect your entire system and security online. Email service providers make frequent modifications to their IP addresses without informing the users, which can result in major SPF failures and negatively affect the deliverability of even legitimate. Such issues can be avoided with the help of automated SPF flattening which ensures your SPF records are always in line with the latest updates and regulations. This is also a faster way to ensure the optimization of your SPF records while avoiding manual errors and resulting security and deliverability issues.
A good tool you can use for auto-optimizing your SPF records is PowerDMARC’s SPF flattening tool. This is a one-click SPF flattening tool that completely automates the process and flattens SPF records in a matter of seconds. It successfully flattens SPF records for multiple domains and accounts. It also helps keep you informed about changes to authorized IPs about which you would otherwise not be notified by your email service provider. The tool helps you stay compliant with the 10 DNS lookup limit and protect your system from a wide range of failures.
The Disadvantages of Traditional SPF Flattening
While SPF flattening offers numerous benefits, it also comes with several drawbacks. These include:
1. Update Management
It is important to organize audits on a regular basis to account for changes in authorized servers. Moreover, you should make use of automation processes with methods such as PowerDMARC’s SPF flattening tool to make consistent updates to your records.
2. Excessive Length of SPF Records
Expanding IP addresses directly in records can lead to excessive length. To avoid this, you can use macros to maintain a compact format. Macros offer a clever workaround for the character length issue when replacing IP references. This approach preserves the important information while avoiding the risk of exceeding length limits.
3. SPF Records Misconfiguration Issues
Keep in mind that records misconfigurations can lead to serious email disruptions. It is therefore important to make use of trusted SPF flattening tools that provide professional support for SPF records misconfigurations and other types of issues.
How To Overcome These Challenges
An easy and helpful way to avoid the above-mentioned SPF flattening limitation is SPF macros. This SPF feature is especially great for domain owners who require a more dynamic and scalable SPF record for their email domain authentication. SPF macros are specialized character sequences within SPF record syntax. They are designed to be dynamically replaced with specific metadata extracted from individual emails undergoing SPF validation. This in turn contributes to more simplified SPF records and avoid excessively long and complicated SPF records.
PowerSPF is a tool that uses SPF flattening and SPF Macros simultaneously to make SPF authentication and record optimization processes as flexible as they can possibly be. It is quite easy-to-use, which enables even non-tech-savvy individuals to enjoy smooth and effective SPF optimization.
How Do SPF Macros Work?
SPF macros are a type of character sequences that help simplify your SPF record configuration. This is done by replacing the mechanisms that are defined within the SPF DNS TXT record (see RFC 7208, section 7).
Even though SPF records are generally simple, sometimes the SPF mechanisms are not enough for an effective and comprehensive email authentication. This makes SPF macros an important and necessary part of your email authentication journey.
To represent SPF macros, a percent sign (%) is used. They comprise of a combination of two or more letters, delimiters, and modifiers. Then, when it comes to the SPF authentication process itself, the SPF macros are carefully assessed and they are replaced with corresponding values.
SPF macros utilize specific symbols like %s and %d to represent the sender’s address and domain associated with the validated identity. Modifiers (r, l, o) can be applied to extract specific parts of the address or domain, while delimiters (-, .) help separate elements within the macro.
Domain owners can use SPF macros to reference certain mechanisms in their SPF record, effectively replacing these mechanisms. When the receiving MTA performs a DNS query, these references are used to extract and expand the mechanisms, resulting in more flexible and manageable SPF records.
How to Choose the Right SPF Flattening Tool?
Choosing the right SPF flattening tool can be quite challenging since there are numerous offers in the market and understanding which tool best corresponds to your needs requires careful consideration of several factors. You can understand which SPF flattening tool best suits your business needs and requirements, try asking yourself the following questions:
- Does the tool provide advanced optimization tools (e.g. Macros)?
- How reputable is the tool?
- Is automation available to you?
- What is the provider’s uptime SLA commitment ?
- Does the tool ensure DNS availability?
- How flexible or limited are the pricing schemes?
- Does the pricing correspond to your budget?
- How easily navigable is the user interface?
- Are automatic updates provided for vendor IP addresses?
- How responsive is their customer service?
- Does it align with your long-term business strategy?
PowerDMARC, the Best Choice for SPF flattening
PowerDMARC is one of the very few vendors in the market that provide Macros optimization for your SPF records. PowerDMARC’s hosted SPF service (PowerSPF) enables you to:
- Benefit from SPF macros optimization, a great alternative to manual or dynamic SPF flattening
- Enjoy reduced DNS lookups
- Make use of easily navigable UI
- Benefit from high uptime, DNS availability, and SLA commitment
- Enjoy automatic SPF error handling
- Stay informed about vendor updates
- Boost your email deliverability rates
- Handle complex SPF setups in an easy and effective way
- Enjoy readily available customer service 24/7
- Have access to services in over 11 global languages
- Benefit from numerous managed services (e.g. DKIM, DMARC, MTA-STS, TLS-RPT, and BIMI)
- Optimize your SPF record in a matter of seconds by copying and pasting your existing SPF record into Hosted SPF
Summing Up
Now that you know the advantages and disadvantages of SPF flattening, you can choose for yourself which method works best for your needs and the criteria you can follow to find the best SPF flattening tool for your business. You also have all the knowledge you need to overcome the challenges of SPF flattening and effectively benefit from the advantages that it offers. If you would like to learn more or experience the power of PowerSPF by yourself, sign up for a 15-day free trial!
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