"You want to have more visibility into what is going on in your network," says OpenDNS's Nunnikhoven. "That means that you can look at each one of those devices in turn or you can try to go up a level and look at the overall network visibility."
3. Check outbound traffic
Finally, having a firewall turned on and protecting your computer from outside threats is a no-brainer. But for consumers who want more protection, an outbound firewall — such as Little Snitch for Mac OS X and GlassWire on Windows — can alert them to potentially malicious applications trying to connect out to the Internet.
Outbound firewalls, on the other hand, have a somewhat noisome learning curve. Every time an application attempts to communicate with the Internet, the user must allow or deny the request. The firewall will remember the answers for the future, but it generally takes a few days to get to a point where the firewall is not inundating the user with alerts.
Still, the effort can pay off, says Nunnikhoven.
"There is no magic bullet for security," he says. "But with a few relatively low-cost tools, you can create a good layered defense."
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