Private Tunnel is a commercial spin-off of OpenVPN Technologies, the developer behind the open-source OpenVPN software suite. This is a popular alternative to the L2TP/IPsec and PPTP protocols used to tunnel traffic through encrypted internet links. There are three principle VPN protocols in common use today. The weakest is PPTP, developed by Microsoft and generally considered to be wide open to nation-state intelligence agencies and gifted hackers. Then there’s IPsec over L2TP, a popular choice but with question marks raised by respected security experts since its release in the 1990s, when it was developed by committee with the NSA. These doubts were greatly amplified after 6 Sept 2013 when the BULLRUN and EDGEHILL programs were decloaked in published Snowden documents. Also see: How to use a free VPN: A step-by-step guide. Which leaves OpenVPN as a possibly secure VPN protocol. It is an open-source implementation for virtual private networks based on SSL/TLS key exchange, followed by symmetric ciphers to transport user data. But since it’s based on OpenSSL, the OpenVPN system cannot be seen as bulletproof in its security, as last year’s Heartbleed vulnerability very publicly showed. It’s worth adding that Private Tunnel swiftly announced after the initial Heartbleed disclosure that its implementation of OpenVPN included perfect forward secrecy (PFS), such that an adversary can only access captured data from one decrypted session. In other words, to have your VPN link compromised the session key must be cracked each time you use the service. Also see: How to watch US Netflix in the UK. Private Tunnel has an unusual business model in its commercial VPN service. Rather than sell you VPN server access by the month, it meters the data that you use. So you simply need to top-up your account with however much data you need. The first hit of 100 MB is for free. That’s handy, to enable you to try with no obligation to see if the service works for you. Thereafter data packages are sold at $12 for 50 GB, $20 for 100 GB and $50 for 500 GB. According to Private Tunnel, and ‘average’ user transfers around 90 to 120 GB per year, although it’s not clear if that’s a median, mode or mean user. Traffic is measured as the sum of up and download data. Alternatively you can try referring other people to the service. For every person you get to use the service, you receive 200 MB for free. And thereafter for every data purchase they make, you get 10 GB added to your account. Also see: Why you need a VPN. Server choice is much more limited than most other services. We counted 3 US servers (New York, San José and Chicago), 1 UK, 1 Swiss, 1 Canadian and 1 Nederlands. Using the NY server, we measured 26 Mb/s download and 16 Mb/s download, a good transatlantic result even if latency rose to an understandably higher 78 ms. Moving ourselves back to London we hit 50 Mb/s down and 43 Mb/s up, with 25 ms ping. Also see: How to watch US Netflix on an Android phone or tablet.
Private Tunnel review: Software
Private Tunnel only officially supports its own proprietary software to connect to its VPN servers, and this is available for Windows and OS X. Dig more deeply into its website and you learn that you can use other platforms, providing there is existing OpenVPN software support. For Mac users, for example, there is the open-source Tunnelblick interface released under GPLv2. To enable this you will still need to download your personal profile as a .pvn file from the Private Tunnel website, and import this into your system. The software that the company provides is minimalist, just providing a means to log in and authenticate, and switch between the seven available server locations. There is a Settings tab in the program’s interface, but whenever we clicked on it we were instead logged out of the service. Most troubling though is a data leak in the Mac OS X version, which makes a connection to Google’s servers without even the benefit of an encrypted tunnel. When we reported this to the company we were told its engineers were now addressing these issues and plan to have a fix in the next release due late March 2015.
