What is a Secure Web Gateway (SWG)? A Complete Guide for Modern Businesses

Key Features of a Secure Web Gateway

Secure web gateways include several important capabilities that work together to protect your users and data. These features address different aspects of web security without creating unnecessary complexity.

URL Filtering

URL filtering controls which websites users can access. The SWG categorises websites based on their content and either allows or blocks access according to your company policy.

This feature:

• Blocks known malicious websites that distribute malware or host phishing pages

• Prevents access to inappropriate content categories

• Limits access to non-work websites during business hours

• Controls which web applications employees can use

URL filtering uses constantly updated databases of website categories and reputation scores to make these decisions quickly and accurately.

Malware Protection

SWGs scan all web traffic for viruses, ransomware, spyware, and other malicious code. This happens in real-time as content is being accessed.

Modern malware protection includes:

• Signature-based detection that identifies known threats

• Behavioural analysis that spots suspicious activity patterns

• Sandboxing that tests unknown files in an isolated environment

• Zero-day threat detection that identifies previously unknown attacks

This multi-layered approach catches more threats than traditional antivirus software alone.

Data Loss Prevention (DLP)

Data loss prevention stops sensitive information from leaving your organisation through web channels. The SWG monitors outgoing traffic for confidential data patterns.

DLP capabilities can identify and protect:

• Personal information like social security numbers or health data

• Financial details including credit card numbers

• Company confidential documents and intellectual property

• Regulated information that must be handled according to specific rules

When the system detects someone trying to upload or send sensitive data, it can block the transfer, alert security teams, or encrypt the information automatically.

Application Control

Application control lets organisations manage how web-based applications are used. Rather than simply blocking or allowing entire applications, it provides granular control over specific functions.

For example, you might:

• Allow employees to view content on social media but not post

• Permit cloud storage access but prevent file sharing with external users

• Enable video conferencing but disable file transfers

• Allow limited personal web use while blocking high-risk activities

This balanced approach helps organisations maintain security without unnecessarily restricting useful tools.

SSL/TLS Inspection

Most web traffic today is encrypted using SSL/TLS protocols (shown as HTTPS in your browser). While encryption protects privacy, it can also hide threats. SSL inspection allows the SWG to see inside encrypted traffic.

The process works by intercepting the encrypted connection, decrypting the content, scanning for threats, and re-encrypting the traffic before sending it on.

This inspection is essential for security but must be implemented carefully to respect privacy and legal requirements. Many SWGs allow exceptions for sensitive categories like banking or healthcare websites.

SWG vs Other Security Solutions

Secure web gateways are just one part of a complete security strategy. Understanding how they compare to other security tools helps clarify their specific role and value.

Firewall vs SWG

Firewall: Controls network traffic based on IP addresses, ports, and protocols. Focuses on network-level traffic rather than web content and is less application-aware than an SWG.

VPN vs SWG

VPN: Creates encrypted tunnels for secure remote access. Provides secure connectivity but doesn't inspect content or enforce web policies.

CASB vs SWG

CASB: Secures cloud application usage. Specialises in cloud apps only, while SWGs cover all web traffic.

DNS Security vs SWG

DNS Security: Blocks access to malicious domains. Works at the domain level only and can't inspect actual content.

Many organisations use these tools together for layered security. For example, a firewall might control overall network access, while an SWG specifically handles web traffic, and a CASB provides detailed control over cloud applications.

Modern security approaches increasingly combine these functions into unified platforms. Secure Access Service Edge (SASE) solutions, for instance, integrate SWG capabilities with other security functions in a cloud-delivered service.

Choosing the Right Secure Web Gateway

Selecting an appropriate secure web gateway involves considering your organisation's specific requirements and constraints. Here are key factors to evaluate:

Deployment Options

SWGs come in different forms: Cloud-based services that protect users anywhere, on-premises appliances for local control, or hybrid approaches that combine both methods. Your choice depends on factors like where your users work, your existing infrastructure, and your management preferences.

Performance Impact

Security inspections can potentially slow down web access. Look for solutions that minimise latency through techniques like distributed cloud architecture with points of presence near your users, selective inspection that prioritises high-risk traffic, and caching capabilities that improve response times.

Integration Capabilities

The SWG should work well with your existing security tools and systems. Consider how it connects with identity management systems for user authentication, security information and event management (SIEM) for centralised logging, and endpoint protection platforms for coordinated security.

Scalability

As your organisation grows, the SWG should grow with you. Evaluate whether the solution can handle increasing user numbers, traffic volume, geographic distribution, and new applications and services.

Management Complexity

Some solutions are easier to administer than others. Consider factors like intuitive policy creation and management, automated updates and threat intelligence, comprehensive reporting and alerting, and support for delegated administration.

Total Cost

Look beyond the initial purchase price to understand the full cost, including ongoing subscription or maintenance fees, implementation and integration expenses, training requirements, and administrative overhead.

The right choice balances security effectiveness, usability, and cost considerations based on your organisation's specific needs.

Secure Web Gateways in Modern Security Frameworks

Secure web gateways increasingly function as part of broader security frameworks rather than standalone tools. This integration provides more comprehensive protection and simpler management.

SASE Integration

One prominent framework is Secure Access Service Edge (SASE), which combines networking and security functions in a cloud-delivered service. In SASE, the SWG works alongside other security components like Zero Trust Network Access (ZTNA) for secure application access, Cloud Access Security Broker (CASB) for cloud application control, Firewall-as-a-Service (FWaaS) for network protection, and Data Loss Prevention (DLP) for information security.

This integrated approach offers several advantages: consistent security policies across all access methods, simplified management through a single platform, better visibility across different security functions, and improved user experience with optimised traffic routing.

Next-Generation Capabilities

Next-generation secure web gateways are evolving to support these frameworks with enhanced capabilities like advanced threat detection using AI and machine learning, improved handling of encrypted traffic, better integration with identity and access management, and more sophisticated application controls.

For organisations planning their security strategy, considering how an SWG fits into these broader frameworks can help future-proof investments and simplify security management.

Getting Started with Secure Web Gateways

Implementing a secure web gateway involves several steps to ensure effective protection without disrupting normal business operations.

Assessment Phase

Start by assessing your current environment and security needs. Document your existing security tools and how they'll interact with the SWG, user locations and how they access the internet, critical web applications and services, and regulatory requirements that affect web access.

Policy Development

Next, develop clear policies about acceptable web use. These policies will guide your SWG configuration and should balance security needs with practical work requirements.

Phased Deployment

When deploying the solution, consider a phased approach: begin with monitoring mode to understand current usage patterns, implement basic security policies for high-risk categories, gradually expand policy enforcement based on findings, and fine-tune settings to address any issues that arise.

User Communication

Provide clear communication to users about what's changing and why. Explain how the SWG helps protect both them and the organisation, and establish a process for handling legitimate access requests that might be blocked.

Secure Your Web Traffic with Cloud Gateway

Ready to secure your web traffic with a solution that actually works? At Cloud Gateway, we integrate secure web gateway capabilities into our unified NaaS platform, giving you the protection you need without the complexity you don't want.

Our approach combines cloud-native flexibility with managed service support, enabling fast deployment, complete visibility, and robust security—all backed by industry expertise. As the UK's only tech-enabled MSP with secure access to both HSCN and PSN, we understand the unique challenges facing NHS and public sector organisations.

Get in touch to discover how we can help secure your organisation's web traffic as part of a complete networking solution that makes change easy.