Although the subjects are often confused (and are related), internet privacy and internet security are different issues. This article focuses on secure Virtual Private Network (VPN) services that offer very high levels of technical security.
In practice this means:
- They use strong OpenVPN encryption.
- They use software that prevents any and all forms of IP leak.
- Their software has a kill switch feature.
- They don’t make any silly noob mistakes.
Great technical security provides robust protection against hackers accessing your online activity, be they criminals or working for your government.
What it will not do is prevent a powerful government, the police, or the mafia, from demanding that your VPN provider hand over any logs it keeps relating to your online activity. If such a scenario is part of your threat model, then be sure to also pick a good no logs VPN service for maximum privacy.
Best Secure VPN Services: Summary
|1||ExpressVPN review||$6.67 / month||Visit Site|
|2||Windscribe review||$7.50 / month||Visit Site|
|3||AirVPN review||$4.82 / month||Visit Site|
|4||VPNArea review||$4.92 / month||Visit Site|
|5||NordVPN review||$3.29 / month||Visit Site|
- 30-day money-back guarantee
- No usage logs
- Servers in 94 countries
- Great customer service
- P2P: yes
- Connection logs
- A bit pricey
ExpressVPN now matches this with truly excellent technical security. It uses AES-256 cipher for OpenVPN, with an RSA-4096 handshake and SHA-512 keyed-hash message authentication code (HMAC). Perfect forward secrecy is provided courtesy of Elliptic Curve Diffie–Hellman (ECDH) key exchanges for data channel encryption.
This is great. In addition, unlike most iOS apps, the ExpressVPN iOS app uses OpenVPN. Add in full Domain Name System (DNS) leak and Web Real-Time Communication (WebRTC) leak protection, along with a firewall-based kill switch, and it is clear that ExpressVPN offers exceptional VPN security.
Additional features: three simultaneous connections, “stealth” servers in Hong Kong, free Smart DNS, .onion web address.
- No logs
- SSL tunnelling
- Unlimited simultaneous connections
- Limited free service (10GB)
- Limited customer support
- New service (less established)
- Based in Canada
When reviewing Canadian company Windscribe we found the encryption their service uses, is among the best available anywhere. Which has made something of a splash on the VPN scene.
OpenVPN uses AES-256 with RSA-4096 handshake and SHA512 authentication. Perfect forward secrecy (PFS) is used, and DNS and Internet Protocol version 6 (IPv6) leaks are blocked by the firewall in the custom client. This firewall also acts as a kill switch, and should prevent any WebRTC leaks.
Like NordVPN, our review of Windscribe found that it supports “double VPN” chaining. I am yet to be convinced about the security value of this, but others disagree. It certainly does no harm as an extra feature to have, if you want it.
- No logs at all
- VPN through Tor
- SSL and SSH tunneling
- Accepts bitcoin
- Peer-to-peer (P2P): yes
- Very techy
- Customer support could be better
AirVPN is at the top of the game when it comes fast, secure VPN technology, but its tech-heavy focus and rather brusque support manner alienates many would-be users.
OpenVPN uses AES-256 with RSA-4096 handshake, HMAC SHA1 data channel authentication, HMAC SHA384 control authentication, and DHE-4096 for perfect forward secrecy. It allows users to connect completely anonymously to its servers via the Tor network, and can hide OpenVPN communications inside a Secure Shell (SSH) and Secure Sockets Layer (SSL) tunnel.
The open source desktop client disables IPv6, and its “network lock” feature acts as a kill switch and prevents DNS leaks. WebRTC leaks are blocked by both the network lock function and at the server level. This protects users from WebRTC leaks, even when using the generic OpenVPN app. Furthermore, AirVPN runs its own bare metal servers.
Additional features: real-time user and server statistics, three-day free trial, three simultaneous connections.
- No logs
- Based in Bulgaria (no data retention)
- Five simultaneous devices
- Great customer service
- P2P: ok
- Uses Virtual Private Server (VPS) instances
This friendly, Bulgarian secure VPN provider uses AES-256 with RSA-2048 handshake and SHA256 data authentication for its OpenVPN connections. PFS keys are re-negotiated regularly during each session.
VPNArea’s desktop client is a custom version of Viscocity, and offers DNS leak protection, disables IPv6, and provides a per-app kill switch.
The auto IP feature changes your IP every five minutes, which is interesting. VPNArea uses a mix of VPS instances and bare metal servers, but support assures me that whatever the circumstances, it maintains complete control over its servers.
- No logs at all
- Six simultaneous devices
- Servers in 47 countries
- 30-day money-back guarantee
- OpenVPN encryption with PFS
- Issues with support
NordVPN is a no logs VPN provider based in Panama. This alone makes it one of the best VPN choices available for privacy fanatics, as it puts it comfortably outside the direct influence of both the NSA and copyright holders.
It backs up this privacy-friendly stance by using great encryption, and accepting potentially anonymous payment in bitcoins. Although I have to be convinced of its utility, many also value NordVPN’s support for “double-hop” VPN chaining (which essentially routes traffic through two servers rather than one).
NordVPN uses the DHE-RSA-AES256-SHA encryption suite for its OpenVPN connections. This almost certainly means ordinary RSA-2048 key encryption and HMAC SHA1 authentication, which is just fine. Use of a Diffie-Hellman key exchange provides perfect forward secrecy.
It is worth noting that NordVPN’s iOS app also uses an impressive level of encryption – Internet Key Exchange (IKE) ciphers (phase1) to negotiate keys are AES-256-GCM for encryption, with SHA2-384 to ensure integrity, combined with PFS and 3072-bit Diffie-Hellmann keys.
Unusually, NordVPN’s Mac OS X client uses IKEv2 with Cisco’s NGE (Next Generation Encryption) protocol, instead of OpenVPN. Please check out my Complete VPN Encryption Guide for the pros and cons of IKEv2. The NordVPN client has a per app kill switch. This is undoubtedly handy, but is not as secure as a firewall-based one.
Additional features: P2P permitted, supports obfsproxy technology to defeat censorship, three-day free trial, dedicated IP available on request.
VPN Security Considerations
The simplest analogy is that encryption is a lock. If you have the correct key, then the lock is easy to open. If someone does not have the correct key but wants to access the contents of a strong box (that is, your data) protected by that lock, then they can try to break the lock.
In the same way that the lock securing a bank vault is stronger than the one securing a suitcase, some encryption is stronger than other encryption. Please check out my Complete VPN Encryption Guide for a detailed but layman-friendly look at this subject.
A VPN protocol is the set of instructions (mechanism) used to negotiate a secure encrypted connection between two computers. A number of such VPN protocols are commonly supported by commercial VPN services.
Although there is some merit in the IKEv2 protocol, OpenVPN is the recommended VPN protocol under most circumstances.
It is fast, reliable, secure, and open source. It has no real downsides, per se, but to be truly secure it is important that it is implemented well. This means the use of strong encryption with perfect forward secrecy.
When it comes to encryption, the devil is in the detail. It is common to see VPN providers say they use “ultra-strong 256-bit” Advanced Encryption Standard (AES) OpenVPN encryption. However, in reality this does not tell us very much.
AES-256 is indeed a strong cipher, but if other aspects of the encryption suite used are weak, then your data will not be secure.
- Cipher – this protects your actual data. AES-256 is now the industry standard, and is recommended.
- Handshake – this secures your connection to the VPN server. RSA-2048+ or ECDH-384+ are secure. Importantly, RSA-1024 and Diffie-Hellman handshakes are not.
- Hash authentication – this creates a unique fingerprint, which is used to validate data and Transport Layer Security (TLS) certificates (that is, to check that the server you are connecting to really is the one you think you are connecting to). HMAC SHA-1 is absolutely fine, but HMAC SHA-2 (SHA-256, SHA-384, and SHA-512) and HMAC SHA-3 are better.
- Perfect forward secrecy – this ensures that new encryption keys are created for each session. OpenVPN should not be considered secure unless PFS is implemented. This can be done either by including a Diffie-Hellman or ECDH key exchange in an RSA handshake, or a DH or ECDH handshake.
OpenVPN will negotiate ciphers between client and server at will. Unless very specific parameters are defined, OpenVPN may default to weak settings. All the providers listed above use strong settings.
All of our full VPN reviews now include a “traffic light” audit of the OpenVPN encryption used by that VPN provider. This is intended to clearly flag-up weaknesses in the cipher suite, in an easily digestible, at-a-glance format.
It is BestVPN.com’s hope that initiatives such as this will improve encryption standards across the VPN industry.
Unbreakable encryption is one cornerstone of what makes a VPN service secure. The other is ensuring that the VPN is actually doing what it is supposed to – hiding your real IP address. If it is not, then you have an IP leak.
To determine if you are suffering an IP leak, visit ipleak.net. If you are connected to a VPN and you can see your true IP address, or even just the name of your Internet Service Provider (ISP), anywhere on this page, then you have an IP leak.*
*An exception to this rule is that Private Use RFC IPs detected by WebRTC are local IPs only. They cannot be used to identify an individual, and so do not constitute an IP leak.
When testing the above VPN service I was connected to a Netherlands VPN server, but could see an IP address belonging to my UK ISP. This could be used to trace my real-life identity and constitutes a clear IP leak (an IPv4 DNS leak).
Please check out my Complete Guide to IP Leaks for a full discussion on why IP leaks happen. In that article I also talk about how to fix them. However, with a secure VPN service you shouldn’t need to! I will note that since writing that article, most good VPN services have now implemented WebRTC leak protection.
VPN connections fail sometimes. This usually happens due to reasons far beyond your VPN provider’s control. There is no point in having a super-secure VPN connection, however, if your real IP address and non-HTTPS encrypted web traffic is exposed the second this happens!
Secure VPN services solve this problem by including a “VPN kill switch” (also called, somewhat more accurately, an “internet kill switch”) with their software.
The most secure way to build a VPN kill switch is using firewall rules that prevent any internet connections outside the VPN tunnel. Such rules also prevent DNS leaks.
A less secure way to build a VPN kill switch is for the software to detect that a VPN connection has been dropped and then disable the internet connection (or block or close specified programs). There can be a delay between the client detecting the VPN drop and it disabling the internet, during which time your real IP might be exposed.
Additionally, if the VPN client crashes, it will leave you without kill switch protection. This can be particularly nasty if the same crash also causes the VPN to disconnect! On the other hand, per-app kill switches are quite handy, and any kill switch is better than none.
Never underestimate humans’ ability to mess up! VPN companies occasionally make elementary mistakes in their security setup. A classic example is sending your login details via plaintext email (it happens!).
Good VPN services provide top-notch security. However, many VPNs on the market do not. It is therefore important not to take claims of “military grade” encryption and suchlike at face value.
The devil really is in the detail. Fortunately, some VPN providers care a great deal about getting the details right. And when good technical security is combined with good privacy practices, then everyone wins!