Secure Web Gateway vs. Firewall: Which One Do You Need?


In today’s digital environment, remote employees are common. In the U.S., 71% of companies allow remote work in some capacity, and many corporations have teams dispersed across countries and continents. Cybersecurity solutions that can protect organizations outside of their traditional physical boundaries are essential.

Secure Web Gateways and firewalls are both important for protecting your company’s resources and your remote employees and preventing data breaches. Read on for more information about which product provides the best protection for your organization.

What is a Secure Web Gateway (SWG)? 

A secure web gateway (SWG) is a hardware or software-based network security solution that helps ensure employees use the internet in a safe and responsible way. A SWG can be deployed on-premises or in the cloud, to monitor, filter, and block web traffic based on security policies defined by your company.

In addition to providing security, a SWG can also help enforce compliance policies, manage bandwidth usage, and improve productivity by controlling access to non-work-related websites and applications.

How Does a SWG Work? 

A secure web gateway (SWG) acts as a sentinel between an organization’s network and the internet. It works by intercepting and analyzing user-initiated web traffic as it passes through a network and applying a set of security policies to determine whether to allow or block that traffic. 

SWGs protect users from accessing malicious or inappropriate content on the internet, downloading malware, sharing sensitive data, or engaging in other risky online behavior by combining several features. 


Organizations can route traffic through a proxy server or configure a network to use the SWG as a gateway to monitor all web traffic that passes through it. 

Traffic Inspection

A SWG inspects web traffic, including URLs, headers, content, and other metadata. It checks each web request and response to determine the nature of the request and its associated risks. Then, it generates reports and analytics that provide visibility into web traffic patterns, security threats, and policy violations.

Policy Enforcement

The SWG will apply corporate security policies, defining what types of web traffic are allowed and what types are blocked. These customizable policies can be based on various criteria such as URL category, file type, content type, user identity, or device type. 

Data Loss Prevention

A Data Loss Prevention (DLP) system within a SWG inspects web traffic for sensitive data like medical information, credit card numbers, social security numbers, or intellectual property and blocks or encrypts the traffic to prevent data leakage. 

Malware Detection 

A SWG with malware detection capabilities uses a combination of signature-based and behavior-based techniques to identify and block known and unknown malware threats, preventing them from infecting user devices.

URL Filter

Using URL filtering, a SWG inspects requested website URLs. It compares them against a database of categorized URLs to determine if the website should be blocked or allowed based on the organization’s policies and prevents users from accessing websites that may contain malware, phishing scams, or other types of security threats.


SWGS can use sandboxing to detect and analyze suspicious or malicious files or programs in a safe and isolated environment. While the file or program is running in the sandbox, the SWG can monitor its behavior and analyze its actions to determine if it is malicious. If the SWG detects any malicious behavior, it can block the file or program from running on the user’s actual system and prevent any potential damage or data theft.

All these features work together in an SWG to provide a layered defense against web-based attacks and ensure a safe and productive web experience for users.

Benefits of SWG

SWGs provide businesses with many benefits, including:

  • Improved Web Security: A SWG can protect users from a wide range of online threats by monitoring and filtering web traffic based on predefined policies.
  • Reduced Risk of Data Loss: A SWG with data loss prevention (DLP) capabilities reduce the risk of data breaches and help ensure compliance with regulatory requirements.
  • Enhanced Productivity: By blocking or limiting access to non-work-related websites and applications, a SWG can help employees stay focused and productive during work hours, reduce bandwidth usage, and improve network performance.
  • Simplified Management: A SWG can centralize web security management, making it easier for IT teams to manage and monitor web traffic, update security policies, and generate reports and analytics. 
  • Cost Savings: SWGs provide a comprehensive set of security features in a single solution, which helps organizations reduce the costs associated with web security.

On the whole, an SWG is an essential component of an organization’s cybersecurity strategy, providing a thorough and proactive approach to web security that can help protect against a wide range of online threats and ensure a safe and productive web experience for users.

What Is a Firewall? 

Like a secure web gateway, a firewall sits between the network and the internet and can be either hardware or software-based. A firewall also monitors and controls web traffic, adhering to predetermined security policies, but its primary function is to prevent unauthorized access to or from a private network while allowing legitimate traffic to pass through.

To determine whether traffic is safe, a firewall inspects data packets as they travel between networks and the internet, comparing their code to known malware databases.

Key Differences Between SWGs and Firewalls

While firewalls and SWGs both play important roles in an organization’s cybersecurity strategy, they are different in their focus and capabilities. To start with, SWGs operate at the application level of a network. They examine HTTP and HTTPS web traffic, while firewalls operate at the network level, focusing on other protocols, such as DNS, that SWG doesn’t assess. There are several other key differences.

Amount of Network Control

Secure Web Gateways (SWG) provide more customized and granular control over web traffic and user activity. This includes setting policies, filtering content, and managing access. Firewalls, on the other hand, have limited control over web traffic and user activity and are mainly focused on controlling network access.

Identification of Malicious Code

Firewalls primarily focus on network security. They examine data packets as they move between user devices and the internet, identifying and blocking malicious traffic from accessing the network. SWGs, on the other hand, are designed to prevent web-borne threats and malware from entering the network via the web. 

Outbound Traffic Management

SWGs and firewalls both work to protect your sensitive information against theft by monitoring and inspecting data as it leaves your network, but they handle outgoing traffic differently. Firewalls typically restrict outbound traffic based on predefined policies, while SWGs allow control over web traffic and user activity.

Data Inspection

Firewalls mainly examine data packets to identify code associated with malicious traffic. In contrast, SWGs inspect web applications and content to detect and prevent internet-based threats.

Protection Method

SWGs allow organizations to set policies and enforce rules for users. They manage access to web applications and content and provide control over employee activity. Firewalls, however, mainly focus on controlling network access, including blocking unauthorized access and traffic.

SWGs vs Firewalls vs Cloud Security Gateways 

While both SWGs and firewalls are used to secure networks, they have different strengths and use cases. Firewalls are typically used to monitor and control traffic between different networks and are particularly effective at protecting against network-level threats such as denial-of-service attacks and port scans.

In contrast, SWGs are designed to provide web filtering and access control for users accessing web-based resources. SWGs are especially effective at protecting against web-based threats such as phishing attacks and malware downloads. SWGs are more likely to prevent attacks that occur as a result of user error or intentional malicious behavior.

Cloud Security Gateways (CSG) are designed specifically for cloud-based resources and provide security controls such as data loss prevention (DLP), threat detection and response, and user and entity behavior analytics (UEBA). As organizations increasingly adopt cloud-based resources, CSGs have become an essential component of cloud security strategy, while SWGs and firewalls continue to play important roles in on-premises network security.

Can You Use SWGs and Firewalls Together? 

A firewall can stop data packets with potentially malicious code from getting to your network, but it isn’t a complete solution. Firewalls work well as part of an integrated protection strategy that includes monitoring features and other network controls. Likewise, an SWG protects users against web-based threats but may not block all malicious code.

Together, SWGs and firewalls create a layered approach to security, enhancing your security posture and protecting your organization from a wide range of threats.

What is a Perimeter Defense? 

Perimeter defense is a security strategy that protects a network or system’s boundaries, or “perimeter,” from unauthorized outside access. Typically, this means using a combination of physical and digital security measures such as firewalls, intrusion detection systems, and access control lists that act as barriers to entry.

The goal of perimeter defense is to create a “hardened” outer shell that can deter or prevent attackers from gaining access to sensitive systems or data. By controlling and monitoring traffic at the network perimeter, perimeter defense can help to detect and block attacks before they can reach vulnerable internal systems or data.

However, with the increasing adoption of cloud-based resources and mobile devices, the traditional notion of a network perimeter is becoming less relevant. Many organizations are now adopting more dynamic and distributed security architectures such as zero-trust networking and Secure Access Service Edge (SASE) to provide more flexible and comprehensive security in the face of evolving threats.

A comprehensive cloud-based solution, like Perimeter81, offers zero-trust networking on a SASE platform that combines a SWG, firewall, and other components like identity and access management (IAM) solutions, network segmentation, and endpoint security solutions to create a layered security approach that protects against both external and internal threats.

SWGs and Firewalls: Use Cases

When deciding whether a business needs a SWG or a firewall, it’s important to determine the specific security requirements and use cases of the organization. Here are some factors to consider:

  • Remote workers: SWGs can provide remote workers with secure access to web-based resources such as cloud applications.
  • Branch offices: Firewalls are better suited for securing network-level traffic between different locations or branches.
  • Globalized teams: Organizations with global teams may face challenges with data sovereignty and compliance requirements, as well as the need to provide secure access to web-based resources for their teams in different regions. A SWG can provide a centralized solution for enforcing security policies and access controls across different locations and networks while providing web traffic visibility. Firewalls may not be able to provide the same level of granularity or visibility for web-based traffic.
  • BYOD: The proliferation of personal devices in the workplace can present significant security challenges, as these devices may not have the same level of security controls as corporate devices. A SWG can provide web filtering and access control for these devices, ensuring that they are not introducing security risks to the organization’s network. Firewalls may not be as effective at filtering web traffic from personal devices.
  • Organizational cloud adoption: Organizations are adopting more cloud-based resources, such as software as a service (SaaS) applications, which can introduce new security challenges. A SWG can provide secure access to these cloud resources while also enforcing security policies and controls, such as data loss prevention and user behavior monitoring.  

SWGs and Firewalls: Essential Components in Your Cybersecurity Solution

Ultimately, the decision between a SWG and a firewall will depend on the unique security needs of your organization. It’s important to conduct a thorough security assessment and evaluate different security solutions to determine the best fit for the organization’s specific use cases and requirements.

While SWGs and Firewalls play distinct roles in protecting your employees and your data, together, they can provide a maximum security solution. Request a demo to see how Perimeter 81’s holistic solution can help you apply the benefits of SWGs and firewalls in your business. 

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