However you are not wholly protected against malware while you are online, because (in theory) malware can be installed on your computer and can be active until the next reboot.

但是在上网的时候不能保证不受恶意软件的侵害，因为(理论上)恶意软件可以安装到你的电脑上并活动到下一次重启。

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Next-generation firewalls (NGFWs) have evolved into the first line of defense against computer malware.

FORBES: Next-Generation Firewalls: What Makes Them Next-Gen