VPNs

SSL VPN Overview

Most long-distance communication these days happens over the internet. There are countless internet-based messaging apps, email providers, and other methods of communication — but that is only the tip of the iceberg regarding online communication. Any interaction on a website, network, or database is also a form of communication.

Recognizing the exchange of data happening over the internet at all times, you could say that the use of the internet is communication in and of itself. But this communication is risky for the user and the network host, which is why adequate security is needed. In this case, security is referring to an SSL VPN.

What is an SSL VPN?

SSL VPN stands for Secure Sockets Layer Virtual Private Network, and is a security technology used for encrypting network communications. SSL VPNs started out typically including communication between any two endpoints, such as a gateway-to-gateway VPN architecture. However, over time many SSL VPN products evolved into being more specific. They now target secure remote access for client devices, while excluding gateways and servers.

How Does SSL VPN Work?

In general, SSL VPNs prevent unauthorized third parties from spying and eavesdropping on communications, which otherwise might result in compromising sensitive data. While it might seem like a concern more suited for a hacker movie, eavesdropping is very real and is among the greatest concerns for businesses, government agencies, and journalists.

It is also a common risk for traffic to be unsecured, which should be kept in mind whenever a client device connects to an external network. In other words, if the client device's network traffic is traveling via the internet or through an unsecured wireless access point, the data is at risk.

SSL VPNs go beyond merely protecting sensitive data from being stolen — they can also prevent dangerous man in the middle attacks, which are common forms of hacking that involve data manipulation and alteration. 

MITM attacks are not a new threat. Attacks like that have existed pretty much since the internet itself went mainstream. As a result, SSL VPN products, which provide adequate protection, have been around for quite a while now.

Numerous services that used to offer dedicated SSL VPN devices now include these capabilities into unified threat management (UTM) systems, or next-gen firewalls (NGFS). 

SSL VPN Products: The Architecture

While SSL VPN products can differ in some aspects, they all have the same architecture at their core. They contain a gateway, or a centralized server, as well as numerous client devices that connect to the centralized unit or gateway.

Other aspects can be different, as mentioned. An example is how one vendor may choose to provide an SSL VPN by using a dedicated router. At the same time, another vendor may offer a VM-based version. Similar differences may exist in other aspects, but the fact is that every SSL VPN product needs a gateway or a centralized server to function.

These differences may also revolve around software, where some providers present their product as clientless, which means that it has no native client application. In other words, all potential users need to do is run a browser, and they can use it to access SSL VPN.

Alternatively, other providers might offer the use of the browser as the primary client interface and have their client run within the browser itself. There are also dedicated client apps that are common when it comes to SSL VPN products designed for mobile devices. These client apps can be installed and configured, so the user doesn't have to depend on the use of the browser.

Any of these options can be useful, depending on the users' needs. Using a web-based client or a dedicated app for mobile devices is considered to be more beneficial because it provides the SSL VPN. This, in turn, provides the user with more resources, including file sharing and other features.

SSL VPN Products: The Cost

A final aspect to consider is the cost of SSL VPN products, especially when it comes to adopting and deploying them. Fortunately, the costs are rather straightforward most of the time:

  • Anyone looking to adopt and deploy SSL VPNs needs to pay for the server/gateway, typically in the form of licensing for the expected number of users.
  • If the number of users grows beyond what the license includes, an additional license can be purchased, increasing the number of users. An alternative is to replace the server/gateway and get a more extensive solution that can 'house' additional users.
  • Establish the number of users that will require SSL VPN products at any given time. Anyone looking to deploy an SSL VPN product should know that their users will need to be verified. Verification is possible through existing authentication services — however, multifactor authentication is one of the best options for security purposes.
  • Lastly, users will require support, as they may need help ensuring that the client is updated properly. Users may also need assistance choosing the best browser, or navigating dialog boxes regarding the download and execution of the browser-based client.

How OpenVPN Can Help With SSL VPNs

SSL VPN products are beneficial and necessary to increase information security. There are numerous threats that can jeopardize sensitive data unless it is adequately protected. Securing data is highly important to businesses and organizations that deal with sensitive information.


OpenVPN Access Server offers traditional software, virtualization-based, and cloud-based products for implementing SSL VPN capabilities. Access Server natively supports Windows, Mac OS X, and Linux client devices, as well as Android and iOS mobile devices. To learn more about the features of Access Server, start here.

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