What do you do when the biggest threat to your cybersecurity lives under your own roof?  It’s a fact of life online: a network is only as strong as its weakest link. For many people, that weakest link is their children. They inadvertently download viruses. They work around security to visit sites their parents don’t want them to. They run up huge bills using their parents’ one-click ordering.  And, most frustrating of all, many of them are far ahead of their parents’ ability to keep them from making mischief—in fact, many of them act as the family’s de facto tech support.  In a recent survey, half of Americans with children under 18 reported that their children had breached their online security in some way. And the cost of those breaches can add up, whether it’s damaged computers, lost productivity or money spent on unauthorized purchases.  Keeping one step ahead of children is all the more complicated because it’s not enough for parents to prevent mischief. They also must be mindful that their children are looking to them for guidance. So any security strategies they use also need to be object lessons that help their children stay on the straight and narrow.  Happily, there are plenty of steps that not only will ensure your security but also make you a useful guide to your child. Here’s a look at the measures you should take.  Well-behaved 5-year-olds and rebellious 15-year-olds represent radically different security risks. Your toddler might accidentally bang on a bunch of keys and rename your hard drive; your fourth-grader might be tech-savvy enough to download a bunch of files—and viruses. Figuring out how to deal with those potential problems involves getting an accurate picture of the technology in your house and how your children use it.  First, make sure you know exactly which machines, devices and files your children use so that you know what you need to lock down. Not just their own computers or tablets; remember that many of us hand our own phones and tablets to our children at times. Also don’t forget any other Internet-connected devices, like your gaming console, e-book reader or cable box.  Next, identify which passwords your child knows and consider which should be adult-only. With preteens, a good practice is to have separate profiles on any device your children use, giving each child a profile that allows them to log in to educational apps or games, while reserving full administrative access for yourself. Teach your children that other people’s profiles are off-limits, and ensure they only have the password for their own profile. Older children will likely want to manage their own profiles and devices and keep their browser history private, but you should still keep track of their access to your own devices and accounts, or shared ones.  Then take a realistic look at your child’s temperament and behavior. Have you got a teen who’s constantly testing your limits? A natural hacker who is relentlessly curious about what she or he can get into, break or reprogram? That means taking a tougher stand on security.  Next comes figuring out just how skilled your children are. You need to track your child’s ability to circumvent parental restrictions, and as they get older, their ability to alter your devices. One way to do this is to approach any surprising discoveries with curiosity and humor, rather than panic. Lightly asking, “How did you manage to rename my hard drive?” is more likely to yield insight than shouting, “What made you think it was OK to rename my hard drive?”  There are other tactics you can use to see what your children know. Check your own browser history regularly, as well as your children’s, to see what they are browsing (and look for gaps in browsing history that suggest they’ve figured out how to purge their history). Notice if you find an app running on your phone that wasn’t running when you left it on the coffee table. Periodically check your computers for child-initiated downloads by searching for files with recent modification dates.  Next comes securing your network as much as possible, and making sure your children are serious about security.  First, secure your passwords. The best practice is to use a password manager like LastPass or 1Password to generate and remember unique, complex passwords for each site you use. What matters is that you use different passwords in different places, and that you don’t use a password your children might guess.  Second, make sure that the files on your personal computer are shared only if someone accesses your computer with a password. That way, your children can’t access, delete or modify files on your computer by logging in remotely.  Third, set up a backup system for all the computers and devices in your home. The best approach is to rotate between two backup drives, so if your child downloads something that infects one drive with a virus, you’ve still got a previrus backup.  Fourth, prevent unauthorized purchases by turning off one-click ordering and ensure that each in-app purchase and media download is possible only by entering a password.  That covers the basics. Next comes the more complicated part: teaching your children to reduce the risks of their online activities. Show them how to recognize the difference between a trusted source and a potential source of malware. Show them how to choose a secure password or use a password-locker application. Educate them about when to use real names online, and when a pseudonym is safer.  And yes, awkward though it may be, talk to your teen (or even preteen) about pornography. Chances are they will stumble on it or go searching for it themselves. So teach them how to avoid stumbling onto disturbing imagery, browse anonymously, stream rather than download and avoid clicking on any link that could introduce malware into your system.  While good security practices can reduce your overall level of risk, you also need a plan for when that plan fails.  If your children are used to talking with you about what they do online, train them to report breaches. Let’s say your child shows you how she got around parental restrictions on her phone. You can ground her—and ensure that next time, she keeps her hack to herself. Or you can praise her ingenuity.  This teaches her to tell you about any activity that could weaken your security. It also subtly encourages her to keep curious, and keep developing problem-solving skills. Likewise, asking children to help you fix any problems they’ve caused not only teaches them to take responsibility, but also helps them keep their skills sharp.  Of course, it can be hard to take this kind of measured response when you’re looking at a virus-ridden computer or a $700 bill for in-app purchases. That’s why you want to plan both your parenting and tech-recovery strategy before disaster strikes.  Dr. Samuel is a technology researcher and the author of “Work Smarter with Social Media.” She can be reached at reports@wsj.com.
They are always making mischief online, one step ahead of their parents. Here’s how to rein them in—and teach them life lessons, too.