Emails are among the most commonly used and cost-effective communication channels for individuals, brands, and marketers alike. However, they are not free from their fair share of security risks. In fact, a whopping 91% of all phishing attacks originate from emails. This alarming figure underscores the importance of securing your email servers, especially if you are an organization that sends and receives emails in large volumes. It also justifies major organizations investing heavily in network and email security.
This guide will explore email firewalls, discuss their importance, determine whether you need one, and, if you do, explain how to set one up.
What are email firewalls?
Email firewalls are email security systems that monitor and filter email traffic to ensure the safety of an email server. They are often used as a catch-all term to describe a comprehensive security solution that includes tools such as secure email gateways (SEGs).
An email firewall acts as a shield that protects your server from various harmful cybersecurity threats through email.
How do email firewalls work?
Email firewalls make use of various methods to provide comprehensive email security. These methods include:
- SMTP-level filtering
- Content filtering
- Sender verification
- Spam filtering
- Phishing detection
- Behavioral analysis
- Encryption
- Data loss prevention
Email firewalls may also make use of machine-learning algorithms to implement these methods.
Email firewalls vs spam filters
Email firewalls are often confused with spam filters. However, there is a significant difference between them. While spam filters block unwanted bulk emails, email firewalls provide more comprehensive security against complex and targeted cybersecurity threats.
Well, [an email firewall] is like a spam filter on steroids. They basically do everything that a spam filter does and more. They have the capability of blocking phishing attempts, finding malware, and even blocking those spam emails before they reach your inbox.
- Sofia Perez, Content Manager and Owner, CharacterCounter.com
Email firewalls also offer more scope for personalization than spam filters, as they allow you to set up a security infrastructure that is tailored to your organization’s specific needs. For instance, unlike a spam filter, an email firewall lets you decide what kind of emails you want to allow into your server and how you would like to treat different threats.
Email firewalls vs firewalls
There is often confusion between email firewalls and firewalls. A firewall, also known as a network firewall, is a security system that prevents unauthorized access to a computer network by monitoring and filtering network traffic. They are essential for broader network security threats and cover a wide range of internet protocols like TCP, UDP, ICMP, etc.
On the other hand, email firewalls are specialized firewalls that are better equipped to detect and neutralize email-based threats. Email firewalls specialize in email protocols such as SMTP, POP3, IMAP, etc., and perform deep content inspection of emails. They also offer other email-centric features such as content filtering, email encryption and data loss prevention (DLP).
Why are email firewalls important?
Emails are one of the primary channels through which cybersecurity attacks are carried out. Malicious emails can harbor a wide range of new threats, including zero-day threats, i.e., unknown vulnerabilities in your hardware or software.
Traditional email security systems that consist of spam filters and SEGs alone may be unable to counter these email threats. For instance, Cofense reported a 104.5% increase in the number of malicious emails that bypass secure email gateways (SEGs). In this context, advanced systems such as email firewalls are becoming more relevant for email security.
Cybersecurity attacks can be extremely costly and completely disrupt the regular functioning of servers. In the United States alone, the average cost of a data breach was calculated as 9.48 million US dollars in 2023. These attacks can also cost you precious time. According to a 2023 research report, each IT staff member assigned to resolving a security breach spent an average of 427 hours in the remediation process.
Additionally, a cyber attack can lead to the loss of an organization’s precious data and even lead to huge privacy breaches through customer data leaks. As a result, the organization may lose credibility, which might not be recovered easily. Therefore, a proper email security system is in all stakeholders’ interest.
Who needs an email firewall?
Email firewalls can provide additional security to any email server since it is always better to be safe than sorry. However, they are vital to organizations at a greater risk of advanced cyber threats. For instance, an email firewall should be an essential part of a business’ cybersecurity apparatus if it has to handle large volumes of sensitive information like customer data, data related to the state or share market, and so on.
Organizations that generally deploy advanced email firewalls include email service providers, government agencies, large corporations, hospitals, financial institutions, etc. While smaller organizations may also deploy email firewalls, they are comparatively less complex.
How to set up an email firewall
Setting up an email firewall can depend on various factors, such as the complexity of threats that the email firewall has to protect against and the size of the email server. Generally, setting up an email firewall consists of the following steps.
- Selecting the right solution: With the help of an email security expert, you can choose between on-site hardware firewalls, software solutions, or cloud-based services. This will depend on the specific needs of your organization.
- Configuration: Once you have selected and deployed your firewall, you must configure the various filtering rules depending on the level of security and compliance you require. This step involves a lot of personalization.
- Testing and optimization: Once the email firewall is set up, thorough testing must be conducted to ensure that the filtering process is working efficiently. Based on the testing results, the email firewall must then be optimized.
Setting up an email firewall can be as straightforward as activating a cloud-based solution or as intricate as configuring an on-premises system. It's akin to choosing between coffee and a gourmet blend – both can achieve the desired outcome with varying degrees of effort and personalization.
- Andrei, Co-Founder & CEO of DontPayFull
Email firewalls and deliverability
Many marketers have concerns regarding how email firewalls can affect the deliverability of their email marketing efforts. However, good marketers don’t need to worry about being affected by these email firewalls unless they’re specifically targeted.
On the other hand, to avoid being flagged by email firewalls or spam filters, you must maintain your domain reputation, take steps to become a high-quality sender and follow the relevant email sender guidelines.
Check out this engaging conversation with domain experts that can help you better understand and maintain a good relationship with every inbox on your email list.
Conclusion
Emails are the backbone of many organizations’ day-to-day functioning. As hackers and other malicious actors find new ways to attack, robust email security systems are a must-have. There is also a need to understand these various threats and customize your defenses based on your needs.
Email firewalls are becoming more and more relevant in this context to ensure email servers’ safe and effective functioning. On the other hand, from a marketer’s perspective, advancements in email security systems require that you keep up to date with best practices to ensure good deliverability and safety for your organization and your audience.
