If you’re keen to use all the cool new gadgets that are coming on the market, but are wondering how you can protect your network from their inevitable vulnerabilities, I have a suggestion for you: Three Dumb Routers.
First, I’ll explain, in simple terms, what it takes to set this configuration up, and then I’ll try to briefly explain why it is a good approach to protecting your network from the Internet of Things, assuming you really have your heart set on playing with these things, or at least showing them off.
The Three Dumb Routers solution is one that is described by Steve Gibson in Episode 545 of the Security Now Podcast. In short, here’s how it is set up.
You need three routers.
One of them will be the Main Gateway router, or what Steve calls the Root router, which provides the common link to the Internet for all your routers. This router is set up on what’s called a NAT configuration, which stands for Network Address Translations, and means that things on the Internet side, can’t access addresses on the “inside” of that router’s network.
The only thing that you would connect to this router on the Local Area Network side (the “inside”, not the Internet or WAN side) are the other two routers. You shouldn’t connect any other devices to the inputs of the Main Gateway router, and it should have wif-fi turned off, if possible. In fact, it may just as well be a non-wifi router.
Then, you need one router for your important (and relatively trusted) computers and devices. This router should also be set up for NAT-ing, which means anything on its Internet side won’t be able to access things on its LAN or “inside” segment.
Finally, you need one router for your untrusted, or potentially insecure devices (e.g. the Internet of Things devices). Again, this router is set up with NAT-ing. So, you will never have any trusted devices on the same segment as your untrusted devices. And the devices in each segment won’t be able to see the ones in the other segment.
Why this configuration provides the lowest risk
The reason that this set-up should be secure is that even if any potentially untrusted device is maliciously configured to scan its LAN environment, and if your important devices are not on that segment, they shouldn’t be visible to that untrusted device. There is a slight chance that the untrusted device might be able to find a way to “see” the network segment that is under the Main Gateway router. But if the only things connected to the Main Gateway router are the other routers, then there should be no other computers or devices (e.g printers, etc.) that can be easily seen or exploited.
NOTE: One disclaimer I have for you if you want to use this approach: Routers have been known to have their own vulnerabilities, and it is possible that if an attacker can identify and exploit a vulnerability on one of your routers, they may be able to gain a foothold, and impact your other network devices. So, this approach is not guaranteed, but it should reduce the risks by quite a bit. It’s also possible that computers or devices in your “trusted” segment could become infected with malware, and could still exploit devices in that network, but this is a risk you’re already assuming when you set up and use a home network.
Here’s a link to a video with a good description of this principle from Steve Gibson on the Security Now podcast, describing why this set-up provides reasonably good security for your network.