Increasing access to the web and the spread of remote workforces and company mobility has led to the emergence of security measures such as the cloud Secure Web Gateway (SWG). In simple terms, an SWG is a browser antimalware proxy solution that detects and filters web traffic.

An SWG uses traditional and more modern techniques to accomplish this, but how exactly does it work, and is this product right for you? Let's find out below.

What Is a Secure Web Gateway?

SWGs have unique characteristics compared to other computer security systems that have been implemented in companies for many years, such as Unified Threat Management (UTM), Zero Trust Network Access (ZTNA), Intrusion Prevention Systems (IPS), and other computer security systems, which add application control functionalities based on Deep Packet Inspection (DPI) and anti-intrusion, based on enabling or authorization, to the traditional firewall of the use of ports, and therefore of associated applications, based on policies defined by the company, group, or user.

So, an SWG is a cybersecurity hardware that secures company information and implements security arrangements and policies. This security posture operates between company employees and the internet (and the cloud). In simple terms, an SWG is just like a water filter in your kitchen, which will remove all dangerous impurities to make drain water safe to drink. In the same way, an SWG filters unsafe content from web traffic to stop cyber threats and data leaks. They also block risky or unauthorized user behavior.

Why Use a Secure Web Gateway for the Cloud?

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In the past, security business processes mostly took place within an internal corporate network. But with the increased reliance on remote workforces and cloud computing, organizations have to use the internet in addition to internal private networks. And as the variety and number of threats on the internet keep growing, from phishing attacks to malware-infected web pages to malicious cloud applications, SWGs are becoming essential for many organizations that rely on the cloud and remote workforces.

How Does a Cloud Secure Web Gateway Work?

Some SWGs work with proxy servers. A proxy server basically represents a different device on the internet that makes requests and receives responses on behalf of your device; that's how if a document contains malware, it stays at the SWG and not in your device. It is important to note that an SWG (this proxy server) can be an actual physical server implemented as local devices or, in some other cases, a cloud-based virtual machine.

Whether an SWG is implemented on-premises or not, all work more or less the same way. When a client device (in this case, your computer, phone, or desktop) sends an access request to a website or application, it will (the request) first goes through the SWG. The SWG will then inspect the request and pass it on back to your device if it assesses it does not violate already pre-determined established security policies.

It's very similar to physical security; for example, an airport screening officer will not only take you through the X-ray but also check you out before letting you through. A similar concept is applied in an SWG where all incoming data is inspected before being passed on to users' devices.

Ideally, an SWG is used by companies that manage employees remotely, which usually rely on the cloud. This allows workers to access the internet through a protected gateway (SWG), which prevents data leaks over the devices and networks of their employees.

How Do Secure Web Gateways Enforce Security Policies?

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For an SWG to work properly, a user must set a policy that all network traffic must follow, for example, that all traffic needs to be encrypted. This policy would mean the SWG would be blocking websites that do not use HTTPS. For an SWG to implement all these policies, it uses the following measures:

URL Filtering

URL filtering is a way to control which websites a user can load, just as with the example above. URL filtering will typically involve using a block list. If a user attempts to load a website on the block list, the SWG blocks the request, and the website does not load on the user's device. This is something a firewall will do; it will restrict access to sites based on their online reputation. An SWG is similar to the Tinywall firewall, which allows you to tailor the types of sites you don't want to access.

Antimalware Scans

Antimalware detection and blocking work similarly to an antivirus, except that one from an SWG will constantly scan your device and the internet for the most elusive or evolved ransomware, malware, and phishing attacks. This means that an SWG examines the data that passes through and checks if it matches the known malware code. Some gateways also use sandboxes to check for malware; they run potentially malicious code in a controlled environment to see how it behaves. If malware is detected, the gateway blocks it.

App Control

An SWGs will detect which apps employees use. This is helpful because an SWG can moderate how much access an app gets to your device. App control can also extend based on a user's identity or location.

Content Filtering

This works similar to a firewall that blocks content the SWG programmer deems inappropriate or dangerous. This must naturally be heavily customized by you or the company's IT department to optimize the content filtering policies.

Data Loss Prevention (DLP)

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DLPs don't necessarily save your data to make sure you don't lose it if your hard drive or cloud is wiped out. Instead, a DLP works like a reverse firewall. It will scan all data that leaves your device and block it from leaving if it detects it is sensitive or is access-controlled by the company. Not all SWG will count with this modality, but it can be valuable to prevent data leaks and safeguard critical information.

Who Should Get a Secure Web Gateway for the Cloud?

Not having a secure web gateway is not as bad as not having an antivirus on your computer, but it's definitely a nice add-on. Remember that an SWG is classified as a very advanced layer of protection.

However, a secure web gateway is essential if you run a business that relies heavily on the cloud and you have several employees working remotely.