VPN Concentrators – CompTIA Security+ SY0-401: 1.1


We’re an increasingly mobile workforce, so we therefore need technologies to keep us secure while we travel. In this video, you’ll learn how VPN concentrators can be used to provide encrypted tunnels from our favorite coffee shop to our corporate network.

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VPN concentrators are becoming increasingly common. You can buy them now for your home office, even, and use VPN software to connect back through an encrypted tunnel to your home office, where you can then print on your local printer, even though you’re somewhere else.

The way these concentrators work is out there on the internet, you may be at a coffee shop, you may be at a hotspot somewhere, and you want to be able to communicate to your corporate or your home network, but you don’t want the people on the internet to see what’s going on. In steps the VPN concentrator.

This is exactly what we’ll do, and by using some software in your operating system or on your machine, you’re able to create an encrypted tunnel through the internet to the VPN concentrator. And it may not just be one person, it may be many, many different people, in some cases hundreds or thousands of people that are connecting through these encrypted tunnels back to the VPN concentrator, and it’s creating now that virtual private network.

Because all of that’s encrypted, even if somebody did get their hands on these packets going back and forth, they wouldn’t be able to do anything with them, because all of the data inside of those packets is protected. The VPN concentrator, then, is doing a lot of hard work. It is decrypting this traffic. It’s putting it onto the internal network, on this green network, and you’re able to communicate as if you were sitting in the same building as all of these devices.

And as the response goes back to your machine, the VPN concentrator is in charge of encrypting that data and sending it across that link again. The process of encrypting and decrypting data is very, very CPU intensive, so very often these VPN concentrators are very, very hardware specific devices, so they can keep up with the speeds that we need to be able to use, because many times you have hundreds or thousands of people coming in.

You’ve got a lot of encrypting and a lot of decrypting to do as that traffic goes by. If you are in a remote location or you or someone who is very mobile, and needs to communicate back to your home office, a VPN concentrator is a practical necessity in today’s security environments.