In this approach, the firewall must be configured with input and output filters on its Internet and perimeter network interfaces to allow the passing of tunnel maintenance traffic and tunneled data to the VPN server. Additional filters can allow the passing of traffic to Web servers, FTP servers, and other types of servers on the perimeter network. As an added layer of security, the VPN server should also be configured with PPTP or L2TP/IPSec packet filters on its perimeter network interface as described in “VPN Server in Front of a Firewall” in this section.
It’s up to you to answer these questions by reading over the documentation provided by the VPN service provider before signing up for the service. Better yet, read over their documentation and then search for complaints about the service to ensure that even though they claim they don’t do X, Y, or Z, that users aren’t reporting that they are in fact doing just that.

While a VPN can protect your privacy online, you might still want to take the additional step of avoiding paying for one using a credit card, for moral or security reasons. Several VPN services now accept anonymous payment methods such Bitcoin, and some even accept retailer gift cards. Both of these transactions is about as close as you can get to paying with cash for something online. That Starbucks gift card may be better spent on secure web browsing than a mediocre-at-best latte.

Are you so used to your data traveling over Wi-Fi that you've stopped worrying about the security of that data—and about who else might be spying on it, or even stealing it for nefarious purposes? If so, you are—sadly—in the majority, and you ought to consider using a viritual private network, or VPN. In fact, when PCMag conducted a survey on VPN usage, we found that a dismal 71 percent of the 1,000 respondents had never used a VPN. Even among those who support net neutrality—who you might think would tend to be well informed on technology and privacy issues—only 45 percent had used a VPN.