Most VPNs won’t keep any logs of user activity. Not only is this of benefit to their customers (and a great selling point) it’s also of huge benefit to them (as detailed logging can quickly consume disk after disk worth of resources). Many of the largest VPN providers will tell you as much: not only do they have no interest in keeping logs, but given the sheer size of their operation they can’t even begin to set aside the disk space to do so.

Challenge Handshake Authentication Protocol (CHAP) is an encrypted authentication mechanism that prevents transmission of the actual password on the connection. The NAS sends a challenge, which consists of a session ID and an arbitrary challenge string, to the remote client. The remote client must use the MD5 one-way hashing algorithm to return the user name and a hash of the challenge, session ID, and the client’s password. The user name is sent as plain text.
ExpressVPN has a wide range of client software, a dedicated proxy service for streaming media and its own DNS service. But in our 2017 tests, it dropped many connections and its overall performance was in the middle of the pack. It also allows only three devices to be connected simultaneously per account, and it's one of the most expensive services we evaluated.
Mullvad is not that easy to use, with a bare-bones desktop interface and, unlike every other VPN service we've reviewed, no mobile client apps. (You do get instructions on how to manually set up OpenVPN apps.) This service's network speeds were far from great in our tests, and it's fairly expensive, with no discount for paying yearly instead of monthly.
Cost: There's a 3 day free trial you can grab but you'll still need to enter your credit card. Otherwise, you can pay for VyprVPN every month for $9.95/month (or buy a year at once to bring that down to $5/month). Additional, there's a Premium plan for $12.95/month (or $6.67/month when billed annually) that lets you use your account on up to five devices at once, plus it supports Chameleon.
Logging Policy – PIA has never been involved in any privacy exposure incident. Moreover, the privacy policy of the company is very clearly defined, which serves to increase user confidence in the reliability of the VPN. PIA clearly mentions that they follow a no-log policy and the fact that they have a clean slate in this regard makes PIA one of the best VPN services for privacy-seeking individuals.
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.