What is a Secure Web Gateway (SWG)?

Organizations can enhance their defense-in-depth strategies by using secure web gateways (SWGs) to protect their users’ internet traffic. SWGs can block malware and malicious websites, prevent data exfiltration, and prevent access to unauthorized sites or web apps. Gartner defines an SWG as “a solution that filters unwanted software/malware from user-initiated Web/Internet traffic and enforces corporate and regulatory policy compliance. This article will explain why organizations use SWGs, how they work, and how a secure web gateway can support your Zero Trust Network Access strategies.

What is a Secure Web Gateway (SWG)?

A secure web gateway protects an organization from online security threats and infections by enforcing company policy and filtering Internet-bound traffic. A secure web gateway is an on-premise or cloud-delivered network security service. Sitting between users and the Internet, secure web gateways provide advanced network protection by inspecting web requests against company policy to ensure malicious applications and websites are blocked and inaccessible. A secure web gateway includes essential security technologies such as URL filtering, application control, data loss prevention, antivirus, and https inspection to provide organizations with strong web security.

How does an SWG Work?

The secure web gateway sits between users and the internet to filter traffic and enforce acceptable use and security policies. Primary SWG capabilities include:

• URL filtering
• Antimalware and threat prevention
• Application control capabilities

The role of an SWG revolves around managing and regulating data flow between the network and the internet.

SWG deployment can take various forms, including:

• Physical servers
• Cloud-based virtual machines and services
• Software applications

Secure web gateways work by inspecting traffic from client devices aiming to connect with internet resources. Each outgoing web request from a client device first connects through the SWG. Serving as the gateway, the SWG authenticates the user and examines the request, ensuring it doesn’t violate acceptable use policies. The SWG only allows the request to proceed if it’s determined to be appropriate and safe. Incoming data undergoes a similar inspection before it can reach users.

SWGs essentially shield users from online threats while enforcing acceptable use policies. They serve as data checkpoints by safeguarding internet access, blocking malicious web traffic and malware, and protecting organizations from data leaks.

Why does your organization need a Secure Web Gateway?

Gone are the days of poorly spelled letters from fake foreign dignitaries – modern cyber attacks look sophisticated enough that even the internet-savvy can fall victim to them. Instead, users might receive a professional-looking email prompting them to click on a link and update their login information for a popular tool. Or, they may encounter a pop-up warning them that their security software is out of date and an update needs to be downloaded immediately.

Attackers design these online pop-ups and phony websites to look almost identical to the real versions. The prompts seem just legitimate enough to entice users to input their login information, share sensitive information like bank account numbers, or download a file. This is where a secure web gateway comes in handy.

The Benefits of a Secure Web Gateway

With Secure Web Gateway technology, organizations can:

• Block threats effectively. SWGs can block access to malicious websites and applications, prevent malware infections, and enforce compliance policies and regulations to keep users, data, and the organization safe.
• Enforce security policies for workers everywhere. Security inevitably becomes more complex as workforces grow increasingly distributed. A Secure Web Gateway can enforce security policies anywhere, allowing employees to authenticate and use the web safely anywhere they work.
• Prevent data leaks. From customer information and credit card numbers to personally identifiable information and intellectual property, SWGs can prevent sensitive and important data from being accidentally or purposefully leaked.
• Support SASE architecture. Secure Web Gateways are an integral part of a Secure Access Service Edge (SASE) approach to security, along with Cloud Access Security Brokers (CASB), Zero Trust Network Access (ZTNA), and Software-Defined Wide Area Networking (SD-WAN).

How does SWG relate to Zero-Trust?

Secure web gateways are built on similar paradigms to VPN and other legacy technologies. Deep down, they assume that certain kinds of traffic are inherently trustworthy. URL filters, for example, assume that any web addresses not included on the deny list are safe for users to visit. When a user reaches a compromised website, the SWG relies on packet inspection and other defense layers to block the threat it lets enter the HTTPS tunnel.

Even though secure web gateways are not inherently Zero-Trust technologies, they can complement Zero-Trust network architectures. Zero Trust is a network access technology that creates secure connections to company resources from authenticated and authorized users. SWGs provide granular control over sources, destinations, content, and other aspects of users’ internet activity. With this additional context, the Zero Trust system can better evaluate whether to allow a user’s connection request — and how much access to authorize.

Common SWG Deployment Challenges

Complexity in Functionality

A common SWG deployment challenge is its inherent complexity. If implemented separately, an SWG can become another point product in a disjointed security stack that requires ad hoc management.

However, if natively integrated with adjacent security technologies, for example, within a secure access service edge (SASE) framework, security teams can have improved visibility and single-pane-of-glass management for easier monitoring and security enforcement.

Impact on User Experience

The process of securing internet traffic using traditional on-premises infrastructure can negatively affect user experiences. Backhauling all web traffic to a centralized data center will likely cause latency and performance degradation, leading to poor user experiences. Poor user experience can hinder worker productivity, cause frustration, and lead users to disable or circumvent security controls.

Evolution of Cyberthreats

The continuous advancement of cyber threats is another significant challenge. Modern cyberattacks have evolved to include tactics where adversaries use legitimate SaaS platforms to host malicious content, employ phishing kits to scale attacks, and execute meddler-in-the-middle attacks to steal credentials. As cyber criminals innovate their attack strategies, traditional SWG solutions that rely on hashes, static signatures, and offline crawling of web content become less effective.

The future of Secure Web Gateways

According to the 2019 State of IT Security survey conducted by eSecurity Planet, web gateways are one of the top IT security spending priorities and a security technology that users have the most confidence in. Although these gateways have been around for some time, their popularity and the need for strong security while accessing the Internet and web applications remotely is not expected to diminish any time soon. Analysts expect a 20% growth in the web gateway market, with sales projected to more than double by 2025, reaching $12 billion. Furthermore, leading analysts notice there is a trend in how secure web gateways are deployed. The market for cloud-hosted secure web gateway services is now outgrowing the market for appliance-based secure web gateways as more organizations move to the cloud.