Understanding Secure Email Gateways: An Introduction for Beginners

Most of our work operations are online today. We transferred the majority of our business communication to digital platforms. Email is probably one of the most popular means.

Just like any other virtual channel, it can be pretty vulnerable. There’s always a possibility of cyberattacks. That’s why proper protection is so necessary. You need to educate your employees and employ secure email gateways.

We want to tell you more about these procedures. Keep reading and learn how to safeguard your data!

About Secure Email Gateways

Our world is turning digital now. As Marco Ciapelli, co-founder of ITSPmagazine said,

Let’s face it: the future is now. We are already living in a cyber society, so we need to stop ignoring it or pretending that it is not affecting us.”

You need to acknowledge that the online realm is where we mostly spend our time. Its safety is a must, especially if it comes to work-related information. As we have already mentioned, we mostly contact via email. So, secure gateways are essential. 

You probably want to know what they are exactly. It is a specialized software solution or service. It filters and protects the traffic that flows in and out of your network. SEG scans all the content and attachments of your messages. It can identify any malicious activities or policy violations. Below, we gathered some of the features it offers.

Inbound and Outbound Traffic Monitoring

SEG intercepts the message from your server before it reaches the recipient’s inbox. It analyzes the information inside and identifies any suspicious points. Also, it uses different threat detection mechanisms. We will explain them in more detail below.

It can send the email into “quarantine” if it notices any issues. You will get a notification about if any additional evaluation is necessary.

Threat Detection Mechanisms

So, we’ve already mentioned these mechanisms above. In this table, we want to highlight their functionalities.

Method Features
Signature-based DetectionMatches content and attachments against known signatures of malware, and phishing scams
Machine LearningUtilizes advanced algorithms to detect patterns of suspicious behavior or emerging threats
Behavioral AnalysisAnalyzes the behavior of senders and recipients to identify unusual activity
HeuristicsApplies rule-based algorithms to detect common characteristics of spam or phishing attempts

Content Filtering

This is another fundamental function of SEG. It’s an examination process of email content. It can help you regulate the flow of messages based on predefined criteria.

One of the most basic forms of content filtering is the assessment of keywords. You can create a custom list of those that may indicate negative intent or prohibited activities.

Also, it can analyze URLs and attachments. This can help you detect dangerous files or links leading to malicious websites. Some SEGs even employ image analysis. That way, you can identify

Policy Enforcement

They enforce policies related to 

It can help you comply with all the industry regulations. SEGs encrypt messages that contain sensitive info before transmission. So, only people with permission can access them.

Moreover, it gives you the possibility to prevent data loss. For example, you can define rules for sharing credit card numbers or intellectual property. It can help you avoid information leakage.

User Interaction

These systems provide notifications and reports. That way you can handle dangerous activities right away. Moreover, they offer training features. Some of them are

Also, they have feedback mechanisms. Users can report false positives and suggest improvements. So, you can fine-tune SEG configurations accordingly.

Practical Solutions

There’s no doubt that email security is extremely important today. It can help you protect your company from different digital threats. Below, we gathered a few services you can use for that purpose.

Microsoft Defender for Office 365

It is a cloud-based email security service. It uses threat intelligence to detect and block phishing messages in real time. This service employs multiple layers of protection. For instance, it utilizes sandboxing technology to detonate questionable files in a controlled environment.

Also, it has anti-spam capabilities. You can filter out unwanted and unsolicited messages from inboxes with its help. This service provides administrators with reporting and analytics tools as well. You can use them to


It’s a solution by Cisco Systems. It has customizable content filtering capabilities. You can create your own criteria to filter out spam or adversarial messages.

Also, this service analyzes headers, sender reputation, and the materials inside. It can help you block fraudulent messages that trick users into revealing sensitive info or credentials.

It has a simple management interface. The system is centralized. So, you can manage it across multiple locations and domains. Moreover, it is available in both cloud-based and on-premises deployment options.


Proofpoint is another cloud-based platform. It offers strong encryption features. This allows you to encrypt outbound messages with confidential data. Plus, it is equipped with the DLP we mentioned above.

It can inspect the links inside the emails. The system evaluates the reputation of web pages right away. Also, this service implements authentication protocols. It allows you to reduce the risk of email impersonation and domain spoofing.


This platform can offer you advanced filtering techniques. Also, it can block sophisticated threats, like

This service has a centralized console too. So, you can control and change the settings from anywhere. It’s pretty flexible. So, it can adjust to the needs of your company as it grows. 

Moreover, it eliminates the possibility of breaches and productivity losses. You can save a lot of costs over time with its help.

A Guide to Implementation

SEGs have proven to be extremely effective in protection. They’re definitely a great choice if you want to safeguard your emails. You probably want to know how to implement them. So, we want to suggest the steps you need to complete.

Assess Your Requirements

You need to begin by evaluating your organization’s requirements. Also, get familiar with all the solutions available in the market. You have to consider factors, like

Plan Deployment

Then you need to develop a deployment strategy. It should outline the scope, timeline, and resources you need. Determine how you’ll deploy the SEG. You can choose between these alternatives:

Prepare Your Environment

Also, you need to confirm that your infrastructure is properly configured and optimized for integration. You may need some additional measures, like

Configure Policies and Rules

Next, you have to define security policies and rules. You’ll need to configure settings, like

Integrate with Security Infrastructure

Then you’ll have to integrate the SEG with your other security solutions and infrastructure components. Some of the elements you need to consider are

This integration allows you to coordinate the detection and response activities.

Test and Tune

We recommend you regularly conduct thorough testing of all the processes. It allows you to validate their effectiveness and determine any configuration problems.

Try to adjust the controls and filtering parameters based on testing results. Also, we suggest you consider ongoing feedback from users and security teams.

Training and Awareness

It’s really important to instruct all users about how the platform operates. You need to teach them how to recognize and report dubious messages. Try to host regular security awareness training sessions. It can help the participants comprehend all the common email threats.


We also recommend you implement monitoring and logging mechanisms. This can help you to track traffic and performance metrics. In order to respond promptly, you need to check for 

Update and Patch

Remember to stay current with any software updates, patches, and firmware. You need to regularly review and update your policies and filtering criteria. Also, try to pinpoint areas for improvement and employ the necessary corrective actions.


The majority of our activities are online today. We work and communicate on different digital platforms. Email is the most widely used instrument for that.

It is susceptible to many threats, just like any other technological advancement. That’s why strong protection measures are so important. Secure email gateways are an ideal alternative for it.

They analyze all the info inside the messages. It can help you identify any malicious activities or phishing attempts. Also, you can use them to filter unwanted materials and protect sensitive data. Moreover, it gives you the possibility to adhere to all the existing regulations and standards.

We hope that our guide was helpful to you. Try to keep up with the newest advancements and make your operations more secure! After ensuring your email communications are secure, integrating strategies to advertise a business online effectively complements your cybersecurity efforts, ensuring your marketing communications reach your audience securely and efficiently.