Secure Web Gateway vs Proxy: Everything You Need to Know

SWG vs Proxy

As more and more businesses move their operations online, the risk of cyber-attacks and data breaches continues to increase. From phishing scams to ransomware attacks, bad actors constantly find new ways to exploit vulnerabilities in enterprise networks and steal valuable data.

Secure web gateways (SWGs) are powerful security solutions that act like double-sided shields to provide a crucial layer of defense against web-based threats. They keep unwanted traffic from gaining access to your network and monitor the data that leaves. By intercepting and inspecting all traffic entering and leaving the network, SWGs can help businesses protect their sensitive information and stay one step ahead of cybercriminals.

What is a Secure Web Gateway (SWG)?

A Secure Web Gateway (SWG) is a security solution that provides web security services to protect against web-based threats such as malware, viruses, and phishing attacks.

A SWG typically sits at the network perimeter and inspects all traffic entering and leaving the network. It can block known malicious websites, prevent malware intrusion, and detect unauthorized attempts to access your network.

Furthermore, SWGs can provide organizations with a centralized way of managing web usage policies, such as blocking access to non-work-related websites or limiting bandwidth usage for certain types of traffic. As web traffic flows, SWGs use several actions to inspect and enforce security policies, including:

  • URL filtering – comparing websites to company-defined denylists and safelists
  • Anti-malware scanning – examining data for known malicious code
  • Application control – regulating applications used on company networks and devices

Depending on the vendor, SWGs may also contain data loss prevention, content filtering, sandboxing, cloud access security brokers (CASBs), and other mechanisms to analyze and manage internet traffic.

A comprehensive SWG is an essential component of an enterprise’s cybersecurity infrastructure, providing an additional layer of protection against cyber threats while also ensuring that employees adhere to acceptable usage policies.

How Does a SWG Work?

A SWG works by intercepting and inspecting web traffic as it flows between the internal network and the internet, comparing it to the rules and policies your company has put in place. Here are the basic steps of how a SWG operates:

  1. Web traffic is directed to the SWG – When a user tries to access a website or web application, the request first goes through the SWG.
  1. Traffic is inspected – The SWG then examines the request. The inspection can include a variety of techniques, such as checking URLs against blocklists or allowlists, analyzing the content of the request for malicious code or suspicious behavior, and verifying that the request complies with organizational policies and regulations.
  1. Traffic is filtered – Based on the inspection results, the SWG will either allow the request to proceed or block it. If allowed, the SWG will forward the request to its intended destination. Otherwise, the SWG will either return an error message to the user or redirect the user to a safe site.
  1. Security features are applied – Besides filtering traffic, a SWG can also apply a range of security features to protect against various types of cyber threats. For example, it can scan email attachments for viruses or malware, inspect encrypted traffic for signs of malicious activity, and prevent users from downloading unauthorized software or accessing non-work-related sites.
  1. Reporting and logging – Finally, a SWG generates reports and logs of all web traffic that passes through it. IT admins can use the information to identify security threats, enforce compliance policies, and analyze internet usage across the organization.

Overall, a SWG is a powerful tool for securing enterprise networks against web-based threats and enforcing acceptable use policies. By intercepting and inspecting web traffic, a SWG can help prevent malware infections, data breaches, and other cyber attacks before they can cause harm.

How to Implement a Secure Web Gateway

SWGs can be implemented in a variety of ways, including:

  • A physical hardware appliance used on-premises 
  • A software package loaded onto physical servers
  • A cloud-based SaaS application

Regardless of whether a SWG is deployed as a physical, virtual, or hybrid solution, they all work in a similar manner, sitting between employees and the internet.

What is a Proxy Server?

A web proxy server is a computer system or application that acts as an intermediary between a user’s device and a web server. Proxies can provide browsing anonymity, filter web content, cache resources for better performance, and increase security for internet users.

When a device requests an internet resource, such as a webpage, the request goes to the web proxy server instead of directly to the web server. The web proxy server then evaluates the request, retrieves the resource from the web server on behalf of the client, and forwards it back to the client.

Web proxy servers can be used for a variety of purposes, including:

  • Anonymity – A proxy server can hide a client’s IP address and other identifying information, providing greater anonymity.
  • Content filtering – Web proxy servers can filter or block certain types of web content, such as websites that are considered inappropriate or unsafe.
  • Caching – Web proxy servers can cache frequently accessed web resources, such as images and videos, to improve performance and reduce bandwidth usage.
  • Security – Web proxy servers can inspect and filter web traffic for potential security threats, such as malware or phishing attempts.

Overall, web proxy servers act as middlemen between clients and web servers, providing a range of benefits for users and organizations, such as improved performance, enhanced security, and greater control over web traffic.

What is a CSAB and How is it Different from a SWG

A Cloud Access Security Broker (CASB) is a security solution that provides visibility, control, and security for cloud-based applications and services. CASBs may run on-premises, in an organization’s data center, or in the cloud.

A SWG focuses on securing web-based traffic and enforcing security policies for internet use and is effective at preventing malware and other browser-based attacks. A CASB is specifically designed to secure cloud-based applications and services, such as Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS), and Infrastructure-as-a-Service (IaaS), and helps prevent data theft, breaches, and unauthorized use of cloud applications. 

When monitoring traffic between the corporate network and the cloud, a CASB provides IT teams with higher control, visibility, and security when using enterprise cloud services. In contrast, SWGs monitor and provide details about web traffic and application use.

A CASB provides additional features beyond web filtering and threat protection, such as cloud application discovery, user behavior monitoring, data loss prevention, and access control. Using strategies like encryption or tokenization, a CASB can protect sensitive data as it travels to and from cloud services, even when the user is on a remote connection or a mobile device.

CASBs can integrate with other security tools, such as SWGs, to provide a comprehensive security posture for cloud-based applications and services. Vendors are increasingly moving toward a combined solution. 

Is a SWG a Proxy?

A secure web gateway acts like a traditional proxy, mediating between client devices and web servers. For example, when a user requests a webpage, the SWG receives the request, retrieves the page from the server, and sends it back to the user.

However, a SWG goes beyond basic proxy functionality by providing additional security features, such as malware scanning, URL filtering, and content inspection. It also allows organizations to enforce their security policies and control access to web content based on user identity, device, and location.

Secure Web Gateways vs Proxies

Proxy servers and SWGs both act as go-betweens from clients to web servers. While businesses can use proxies for various purposes beyond security, SWGs are a more specialized and comprehensive solution focused on security and compliance.

A proxy is a computer system or software that relays information between a client and a web server. Proxy uses include anonymizing web traffic, caching frequently accessed web resources, and filtering web content.

While a SWG is also an intermediary tool, its primary purpose is to protect networks from web-based threats, such as malware, phishing, and other malicious activities. SWGs typically include features like URL filtering, antivirus and anti-malware scanning, SSL inspection, and content filtering.

Overall, the main difference between a proxy server and a SWG is their specific focus and the features and capabilities they provide.

The Importance of SWGs

Organizations face increasing threats from web-based attacks and need to enforce corporate security policies and regulatory compliance. As a result, SWGs are becoming more critical for several reasons:

  • Web-based threats – Many cyber attacks, such as phishing, malware, and ransomware, are delivered via web-based channels such as email, social media, and websites. SWGs help organizations detect and block these threats before they reach end-users.
  • Cloud adoption – As more organizations move their applications and data to the cloud, SWGs provide a way to secure cloud-based traffic and enforce security policies across multiple cloud platforms.
  • Remote work – With the rise of remote work, employees are accessing corporate resources outside the corporate network. SWGs provide a way to secure web traffic from remote locations and ensure remote workers do not compromise the organization’s security posture.
  • Compliance requirements – Many industries, such as healthcare and finance, are subject to regulatory compliance requirements that mandate the use of web security solutions. SWGs provide a way to meet these requirements and demonstrate compliance.

SWGs are becoming more important due to the evolving threat landscape, cloud adoption, remote work, and compliance requirements. By providing web filtering, threat protection, and data loss prevention capabilities, SWGs help organizations secure their web-based traffic and ensure compliance with security policies and regulations.

Traditionally, organizations could secure their networks at the perimeter, but digital transformation, an increased remote workforce, and more complex threats have made the zero-trust network security model critical for enterprises. So users are given access to only the files they need to perform their duties and must be verified to do so.

In a Zero Trust model, a SWG can be deployed as a cloud-based service or on-premises appliance, providing secure access and inspection of web-based traffic from any location, device, or network. By providing secure access and inspection of web-based traffic, a SWG can help organizations reduce the attack surface and strengthen their overall security posture within the Zero Trust model.

Should You Choose a SWG or a Proxy?

Both a SWG and a proxy act as an intermediary between your users and the internet, but if you’re looking for enhanced security, a proxy isn’t enough. While it can provide browser anonymity and faster network performance, an SWG will provide the network and data security you need.

For even further protection of your network and your SaaS applications, along with control and visibility, a combined solution, including SWG and CASB, is the cybersecurity tool you need.

How to Implement a Secure Web Gateway in Your Business

Looking for a secure web gateway for your business? Learn how Perimeter81 can help you meet all your web security, cloud security, and compliance requirements on a single, scalable, secure access service edge (SASE) platform.


What is the difference between a proxy and a gateway?
Both tools act as intermediaries between clients and web servers. While the terminology is often used interchangeably, they do have different functions. Proxy servers provide privacy, filter content, and improve performance, while SWGs protect networks from web-based cyber threats.
What is a CASB?
A cloud access security broker (CASB) is a cybersecurity tool that protects organizations from cloud-based threats, enforces enterprise compliance requirements, and provides greater control and visibility for IT administration teams.
What is the difference between a SWG and a CASB?
CASBs and SWGs have overlapping capabilities but they differ in the main focus and approach to securing cloud and web traffic. CASBs focus on securing cloud-based applications and services, while a SWG protects users from web-based threats and enforces web usage policies, regardless of whether the user is accessing the internet from within or outside of the organization’s network.