Gateway Server - How Does it Work & Types

A Gateway Server is a useful tool for any organization to employ to protect their email. Dive deep with this guide into what they are, how they help, and which ones to invest in.
The customs authority plays a pivotal role in a country's security infrastructure by overseeing the movement of goods across borders.

Acting as a gatekeeper, this institution diligently inspects packages, searching for illegal goods and ensuring compliance with packaging regulations.

Similarly, a gateway server filters email traffic, scanning messages for spam, malware, and malicious content.

By drawing similarities between these entities, we can gain insights into how technology and strategic approaches can strengthen security measures and streamline the movement of goods and information across borders.

What is a gateway server, its importance, and types of servers will be explained in this article.

Let's get started!

What is a Gateway Server?

A Gateway Server is a device that brokers transactions between a client computer and another server. It transforms data streams to match device capabilities.

For example, a WAP (Wireless Application Protocol) gateway server transforms HTML to WML (Wireless Markup Language) for the client’s wireless device.

If you’re not an IT expert, this may sound confusing to you. However, the way this works for email communications should be easy to understand:

Gateway Servers are used to secure email communications between organizations. They act as a gateway or broker between the organization's internal network and the Internet, filtering traffic and blocking malicious or unauthorized emails from entering the network.

How Do Gateway Servers Work?

Gateway Servers work by intercepting email traffic before it reaches the organization's internal network. Emails are scanned for malware or other threats and then either blocked or quarantined if found malicious.

Incoming emails are also checked against a blacklist of known spam addresses, and any emails from these addresses are automatically blocked.

If an email is not on the blacklist, it is then checked against a whitelist of approved addresses.

Only emails from addresses on this whitelist will be allowed through the internal network. All other emails will be blocked.

Basically, every incoming email will be checked for its trustworthiness.

But that’s not all.

Email Gateways will check outgoing content.

Companies will benefit from this data loss protection. Many Email Gateways include an Email Archiving feature, which archives emails for data management and regulatory compliance.

Additionally, they will give businesses continuity features so they can still access their emails even if their email network is down. Companies will also receive a management dashboard, reports, and email gateway analytics.

These allow companies to view all email traffic on a network.

Email Encription Gateways

An email encryption gateway can significantly increase security by automatically encrypting messages and attachments.

Email is the most convenient way to connect with coworkers and peers, but it is not the most secure way to share sensitive information.

An email encryption gateway can scan all outgoing communications and encrypt emails as well as files containing sensitive information. Using administrator-defined policies, these include financial records, customer data, and intellectual property.

Companies can also use gateway servers to filter incoming emails based on content criteria such as keywords, attachment types, or sender reputation.

For example, a company could choose to block all emails with attachments over 5 MB in size or all emails containing specific spam-trigger words, such as "Viagra" or "pornography."

Using a top-notch email encryption service, will help companeis prevent the costly and embarrassing loss of important email-based data sharing.
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Do You Need an Email Gateway Server?

In short. Yes!

No matter the size of your business, a Secure Email Gateway is a security requirement to safeguard your company's data because email communications are a top target for attackers.

Secure Email Gateways provide the most essential level of defense against malicious emails and attachments.

Hackers operate assaults like phishing to access your company's sensitive data via email, which is their top target. Email is weak in company networks, and email attacks are becoming more specialized and focused. A growing range of targeted threats, including phishing scams, ransomware, and malicious attachments, are being faced by businesses across all sectors.

An Email Gateway service offers strong protection for email clients on all devices, not just those in the company. This allows you to protect employees working remotely or using their own laptops for work. They also do not impact the performance of these devices.

This type of server should be your first line of defense. These solutions safeguard organizations by filtering dangerous email content and preventing malicious emails from reaching the inbox.

Cloud-Based Email Gateway Servers

Multiple cloud-based systems are capable of supporting Secure Email Gateways. This category's products are based on hybrid, public cloud, or virtual appliance systems.

Thus, they are all cloud-based and filter email traffic using cloud platforms. With no hardware to install or maintain, using a cloud-based system simplifies deployment and management.

Here are some cloud solutions examples:
cloud-based email gateway servers

Cloud-Flare One

Cloudflare One is an advanced cloud-native email security platform designed to provide robust protection against sophisticated cyber threats. By leveraging its cloud-based infrastructure, Area 1 identifies and blocks malicious attacks even before they reach users' inboxes.

This proactive approach ensures that spear phishing attempts, Business Email Compromise (BEC) attacks, and other advanced threats are mitigated, strengthening organizations' overall security posture.

One of the fundamental advantages of Cloudfare One is its ability to augment the existing security measures offered by cloud email providers. It seamlessly integrates into the existing workflows and infrastructure by establishing deep integrations into popular environments like Microsoft and Google. This integration allows for a more comprehensive defense mechanism, enhancing the built-in security of cloud email platforms.

Its specialized focus on email security provides an additional layer of protection beyond traditional security solutions, reducing the risk of successful email-based attacks and safeguarding sensitive information.

Barracuda Email Security Gateway

Barracuda Email Security Gateway
The Barracuda Email Security Gateway is an advanced email security gateway that efficiently manages and filters all inbound and outbound email traffic, ensuring your valuable communications remain secure and confidential.

It equips organizations with powerful features designed to combat email threats; with its advanced filtering capabilities, the Barracuda Email Security Gateway is an impenetrable defense against malicious attachments, phishing attempts, and other cyber threats lurking within your email system.

Its seamless integration with cloud technologies sets the Barracuda Email Security Gateway apart. With the ability to encrypt messages and leverage cloud-based spooling, this gateway guarantees uninterrupted communication even during mail server unavailability.

The Barracuda Email Security Gateway offers flexible deployment, whether you opt for the virtual appliance or the public cloud environment options like Amazon Web Services (AWS) or Microsoft Azure.

Proofpoint Email Protection

Proofpoint Email Protection
Proofpoint Email Protection is a comprehensive email security solution offered in both on-premise and cloud-based configurations.

Its primary function is to block unwanted, malicious, and impostor emails, providing robust protection against various email threats, including granular search capabilities and offering visibility into all incoming and outgoing messages, enabling organizations to monitor and manage their email communications effectively.

In addition to inbound email protection, Proofpoint Email Protection provides outbound controls, such as encryption and data loss prevention.

These features ensure that sensitive information remains secure via email, reducing the risk of data breaches or unauthorized disclosure, offering continuity capabilities, allowing the company's communications to continue uninterrupted during an email outage, minimizing disruptions, and maintaining productivity.

Phish Protection Email Security

Phish Protection Email Security
Phish Protection Email Security with Advanced Threat Protection is a robust cloud-based email protection suite for businesses.

This comprehensive solution offers real-time defense against various malicious threats delivered via email, using advanced security mechanisms to effectively mitigate risks associated with phishing attacks, malware, ransomware, viruses, malicious links, fraud, spam, spoofing, and other email-based threats.

With it, companies can secure their email communications remain protected and free from harmful content. The suite operates in real-time, swiftly identifying and blocking potential threats without requiring costly tools or software installation.


Secure Email Gateways offer businesses multiple benefits.

They protect employees from email threats like spam, viruses, and phishing attacks, which in turn protects businesses. Employees are the biggest attack vector for business networks, and email is a prime target for attackers to reach employees.

Having a Secure Email Gateway in place allows your business to improve security for employees by scanning inbound and outbound email traffic.

There are several providers on the market that offer a cloud email gateway solution. Finding one that matches your requirements is highly critical, or you will put your data at risk.

We recommend working very closely with your internal IT personnel or having a consultation with a trusted expert in this field.
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