IPSec NAT-T enables IPSec peers to negotiate and communicate when they are behind a NAT. To use IPSec NAT-T, both the remote access VPN client and the remote access VPN server must support IPSec NAT-T. IPSec NAT-T is supported by the Windows Server 2003 Microsoft L2TP/IPSec VPN Client and by the L2TP/IPSec NAT-T Update for Windows XP and the L2TP/IPSec NAT-T Update for Windows 2000. During the IPSec negotiation process, IPSec NAT-T-capable peers automatically determine whether both the initiating IPSec peer (typically a client computer) and responding IPSec peer (typically a server) can perform IPSec NAT-T. In addition, IPSec NAT-T-capable peers automatically determine if there are any NATs in the path between them. If both of these conditions are true, the peers automatically use IPSec NAT-T to send IPSec-protected traffic.
If you don't mind doing a little extra tinkering in a more complicated app to save some money, we recommend TorGuard because it's trustworthy, secure, and fast. TorGuard is well-regarded in trust and transparency; it was also the fastest service we tried despite being less expensive than much of the competition, and its server network spans more than 50 locations, more than twice as many as our top pick. But TorGuard's apps aren't as easy to use as IVPN's: TorGuard includes settings and labels that allow extra flexibility but clutter the experience for anyone new to VPNs.

Among the most critical is how to communicate and exchange information securely between employees sitting at multiple locations. Here is where a VPN or a Virtual Private Network proves to be very handy. It is a fast, reliable, and secure way to exchange information across computer networks, and an excellent, secure mode of communication from remote locations.
As the size of the link state database increases, memory requirements and route computation times increase. To address this scaling problem, OSPF divides the network into areas (collections of contiguous networks) that are connected to each other through a backbone area. Each router only keeps a link state database for those areas that are connected to the router. Area border routers (ABRs) connect the backbone area to other areas.

ExpressVPN attempts to build trust in other ways, even without a public face. Court records from 2017 demonstrate that when Turkish authorities seized ExpressVPN servers in the country looking for information, they found nothing of value, as promised by ExpressVPN’s no-logging policy. ExpressVPN also highlights initiatives such as open-source leak-testing tools, developer content about how the company implements different technologies, and support for the efforts of OpenMedia and the EFF. The ExpressVPN representative even offered to arrange a confidential call between our writer and the owners of the company. However, without being able to discuss their identities or learn about other senior leadership, we believed that wouldn’t have been enough to change our recommendation, so we declined. In the end, trust is such a crucial part of deciding which VPN to use that we had to pass on ExpressVPN.
Password Authentication Protocol (PAP) is a clear-text authentication scheme. The NAS requests the user name and password, and PAP returns them in clear text (unencrypted). Obviously, this authentication scheme is not secure because a malicious user could capture the user's name and password and use it to get subsequent access to the NAS and all of the resources provided by the NAS. PAP provides no protection against replay attacks or remote client impersonation once the user's password is compromised.

One of today’s leading VPN providers and another worthy mention on our list of top 20 VPN services, PureVPN is known for its service quality and customer support. The service has 450 servers in 101 countries, allowing users to surf the Internet and use any online solution without having to reveal their IP address. This is very useful to those who want to bypass Internet censorship.
The solution is downloadable and supports platforms such as OS X, Windows and Linux. Mobile systems like Android and iOS are also supported. These capabilities enable users to use the product on desktops, laptops, smartphones or tablet computers. The software can also be downloaded onto network routers, ensuring that all devices connected to such routers enjoy the same level of protection.
Whether the VPNs you’re familiar with are the ones offered by your school or business to help you work or stay connected when you’re traveling or the ones you pay to get you watch your favorite shows in another country as they air, they’re all doing the same thing. For much more detail on what VPNs are, how they work, and how they’re used, check out this How Stuff Works article.
We spent more than 130 hours over four months researching 32 VPN services, testing 12, interviewing the leadership of five, and consulting information security and legal experts about our results. We found that most people should prioritize other security tools and privacy practices first, but in the cases where a VPN makes sense—such as when you're connecting to public Wi-Fi—IVPN is the most trustworthy provider that offers fast, secure connections with an easy setup process on both computers and mobile devices.
PPTP assumes the availability of an IP network between a PPTP client (a VPN client using the PPTP tunneling protocol) and a PPTP server (a VPN server using the PPTP tunneling protocol). The PPTP client might already be attached to an IP network that can reach the PPTP server, or the PPTP client might have to use a dial-up connection to a NAS to establish IP connectivity as in the case of dial-up Internet users.
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.
Here you should remember that before being sent and received over the Internet, any data needs to first be split into packets. To ensure each data packet stays secure, a VPN service wraps it in an outer packet, which is then encrypted through a process called encapsulation. This exterior packet keeps the data secure during the transfer, and it is the core element of the VPN tunnel. When the data arrives at the VPN server, the outer packet is removed to access the data within, which requires a decryption process.
The Shiva Password Authentication Protocol (SPAP) is a reversible encryption mechanism employed by Shiva Corporation. A computer running Windows XP Professional uses SPAP when connecting to a Shiva LAN Rover. A Shiva client that connects to a server running Routing and Remote Access also uses SPAP. Currently, this form of authentication is more secure than plaintext but less secure than CHAP or MS-CHAP.

Not all mobile VPN apps are created equal. In fact, most VPN providers offer different services (and sometimes, different servers) for their mobile offerings than they do for their desktop counterparts. We're pleased to see that NordVPN and Private Internet Access provide the same excellent selection of servers regardless of platform. These apps received an Editors' Choice nod both for desktop VPN apps and Android VPN apps.
So our advice is to not use a free VPN unless it really is for occasional, very casual use. For the odd IP-hopping use case, they can work. But if you're planning on using the VPN a lot and for streaming video etc we'd highly recommend going for one of the overall best VPN services - they're not free but they're also pretty cheap in the grand scheme of things.

And they manage to do all of this without sacrificing performance, offering one of the fastest download speeds (83 Mbps out of 100 Mbps) and the best 24/7 customer support in the industry. The only downside? It’s a little on the pricey side, with monthly plans starting between $6.67 and $12.95/mo. But it’s a small price to pay for excellent performance in almost every category.
Setting up a Virtual Private Network is a straightforward process. It's often as simple as entering a username and sever address. The dominant smartphones can configure Virtual Private Networks using PPTP and L2TP/IPsec protocols. All major operating systems can configure PPTP VPN connections. OpenVPN and L2TP/IPsec protocols require a small open source application (OpenVPN) and certificate download respectively.
Transport Layer Security (SSL/TLS) can tunnel an entire network's traffic (as it does in the OpenVPN project and SoftEther VPN project[8]) or secure an individual connection. A number of vendors provide remote-access VPN capabilities through SSL. An SSL VPN can connect from locations where IPsec runs into trouble with Network Address Translation and firewall rules.

To verify that each service effectively hid our true IP address, we looked at a geolocation tool, DNS leaks, and IPv6 leaks. When connected to each service's UK servers, we noted if we could watch videos on BBC iPlayer, and using US servers we noted if we could stream Netflix. We also visited the sites of Target, Yelp, Cloudflare, and Akamai to check if our VPN IP addresses prevented us from accessing common sites that sometimes blacklist suspicious IP addresses.

With a StrongVPN account, customers have the ability to choose which server location they want, even down to the specific city. This type of personalized, user-friendly service is also seen with their unlimited server switching, as well as the ability to have up to six simultaneous connections on different devices. StrongVPN supports Mac, Windows, iOs, Android, and even multiple routers, which is a huge plus. 


The downloader. Whether they’re downloading legally or illegally, this person doesn’t want on some company’s witch-hunt list just because they have a torrenting app installed on their computer. VPNs are the only way to stay safe when using something like BitTorrent—everything else is just a false sense of security. Better safe than trying to defend yourself in court or paying a massive fine for something you may or may not have even done, right?

While a VPN can aid privacy and anonymity, I wouldn’t recommend fomenting the next great political revolution by relying solely on a VPN. Some security experts argue that a commercial VPN is better than a free proxy such as the TOR network for political activity, but a VPN is only part of the solution. To become an internet phantom (or as close as you can realistically get to one), it takes a lot more than a $7 monthly subscription to a VPN.
Likewise, if you're connecting via a nation's local carrier, that carrier may be intercepting your traffic, particularly if you're a non-native of that nation. In that situation, if you must connect back to applications and services at home, using a VPN is quite literally the least you can do. Also, keep in mind that if you use your phone's hotspot to connect your computer to the internet, you'll want to use a VPN on your computer as well.
PIA is another great option and offers a 7 day money back guarantee. It keeps no logs, which is a claim that it has proved in court! And although optional, its security can be first rate. Its desktop software supports multiple security options, a VPN kill switch, DNS leak protection, and port forwarding. Up to 5 simultaneous connections are permitted. Its Android client is almost as good, and PIA boasts excellent connection speeds. PIA has servers located in 29 other countries.

Split tunneling is the generic term for software that lets you define which apps send data through the VPN tunnel and which travel outside the tunnel. This lets you route more sensitive activities, like web browsing or online banking, from more mundane but higher-bandwidth activities, like streaming music or playing video games. It's especially useful because Netflix blocks VPN use, as do other services. You can simply route these apps outside the VPN in order to avoid this problem. Not many VPN services offer this feature, but PureVPN does. Seek out split tunneling if speed is of primary concern.


If you’re unsure about whether you should get a VPN, check out our post that explains what a VPN is and when one makes sense as a privacy and security tool. But most people leave their privacy and security vulnerable in ways that can be addressed with methods other than signing up for a VPN—methods that are potentially more effective. If you have a drafty house with paper-thin walls and halogen light bulbs, you’d get far more value out of every dollar by sealing up cracks, insulating, and switching to LEDs than you would by putting solar panels on your roof. Similarly, before you rush to sign up for a VPN subscription, you should consider these other ways to up your privacy game.


A firewall uses packet filtering to allow or disallow the flow of specific types of network traffic. IP packet filtering provides a way for administrators to define precisely what IP traffic is allowed to cross the firewall. IP packet filtering is important when private intranets are connected to public networks, such as the Internet. There are two approaches to using a firewall with a VPN server:
Hi Douglas, I don't want you to publish my previous comment particularly, I'm not trying to attack their company, the comment was mainly for your information - given your comment about ease of use. I finally got it connecting after reinstalling both NordVPN and Avast, then adding exceptions, with all the previously mentioned config mods having been made. I installed the software on a Windows 10 machine, and it still required some mods, but was easier than Windows 7. cheers Nathan
HTTPS is a powerful tool that everyone should use because it helps keep sensitive browsing private at no extra cost to the people using it. But like most security standards, it has its own problems too. That little lock icon in your browser bar, which indicates the HTTPS connection, relies on a certificate “signed” by a recognized authority. But there are hundreds of such authorities, and as the EFF says, “the security of HTTPS is only as strong as the practices of the least trustworthy/competent CA [certificate authorities].” Plus, there have been plenty of news stories covering minor and even major vulnerabilities in the system. Some security professionals have worried about those least-competent authorities, spurring groups to improve on the certificate standards and prompting browsers to add warnings when you come across certificates and sites that don’t withstand scrutiny. So HTTPS is good—but like anything, it isn’t perfect.
Hotspot Shield is an awesome free VPN that has helped millions of people in their time of need. It was the most used VPN during the Turkey coup and the Arab Spring. Users get free access not only to the VPN but also a Chrome extension. The free service permits connections to the US only, but the extension permits connections to 14 countries (but not the US). The result is that Hotspot Shield users can unblock content in 15 countries for free! What’s more, Hotspot Shield’s free plan lets people have 500MB of download use per day. That is a massive usage allowance considering it is free.
Despite some of the drawbacks, ZorroVPN is a very interesting service if you are looking for advanced online anonymity. With their OpenVPN file config generator, you can create unique VPN chains with the Tor network and proxies (up to four hops). Unlike with Perfect Privacy, however, these multi-hop configurations cannot be dynamically changed within the VPN client.
PIA is another great option and offers a 7 day money back guarantee. It keeps no logs, which is a claim that it has proved in court! And although optional, its security can be first rate. Its desktop software supports multiple security options, a VPN kill switch, DNS leak protection, and port forwarding. Up to 5 simultaneous connections are permitted. Its Android client is almost as good, and PIA boasts excellent connection speeds. PIA has servers located in 29 other countries.
Also, do be aware that some broadcasters have developed increasingly sophisticated methods to determine whether the IP address you represent is the IP address where you're located. The VPN may be able to protect your original IP address from being seen, but there are characteristics of proxy communications (like a slightly longer time to transfer packets) that can be used to identify users who are trying to bypass watching restrictions.

Hi Douglas, I don't want you to publish my previous comment particularly, I'm not trying to attack their company, the comment was mainly for your information - given your comment about ease of use. I finally got it connecting after reinstalling both NordVPN and Avast, then adding exceptions, with all the previously mentioned config mods having been made. I installed the software on a Windows 10 machine, and it still required some mods, but was easier than Windows 7. cheers Nathan
Using Wi-Fi on the Windows laptops, we timed how long it took to connect to websites, measured latency times (how long it took a server to respond), and recorded upload and download speeds with Ookla's Speedtest meter, both with and without the VPN activated. We also timed how long it took to download a large video file, both with and without VPN activation.
The basic monthly allowance is only 2GB, but if you register with an email address, that jumps to 10GB. If you run out of data before the end of the month, you can always switch over to the even more generous Hotspot Shield.For even more free data, you can let Windscribe use your computer to mine cryptocurrency. That feature seems a bit creepy, but it's entirely optional and you can adjust the amount of power drawn.
IPVanish can be run on any computer and mobile devices. It is capable of simultaneously using different types of connections. Paying with Bitcoin gives users additional security features as cryptocurrency cannot be tracked unlike government currency. This is because information required when paying with bitcoin are but an email address and a password.
Most VPN services allow you to connect to servers in many different countries. In our VPN directory, we list both the number of servers the service maintains, as well as the number of countries. By default, you'll usually be assigned a server in your home country, but if you want to obfuscate your location, you may want to connect to a server in a different country.
ProtonVPN is available on all your devices including PC, MacOS, mobile, and even your router. A secure internet connection which you can trust is essential every day - for your PC at home, for your mobile device on the road, or your workstation at the office. ProtonVPN works on Windows, macOS and Android via our application, or on iOS, using any OpenVPN client.
Cost: To be billed every 7 days, you can subscribe to ZenVPN on a weekly basis for $2.95, which is equivalent to around $11.80/month. Another option is to just buy it a month at a time for $5.95/month. A third option is to buy a whole year at once (for $49.95) for what comes out to be $4.16/month. The unlimited option is more expensive, at $5.95/week, $9.95/month or $7.96/month if you pay $95.50 for the whole year.
We use the most trusted and widely used VPN protocol available, OpenVPN for your Windows device. This protocol is open source which means you have the reassurance that no unknown proprietary codes can access your data. And to boot we use OpenSSL libraries and run the whole operation over UDP ports so you always get the best speeds when using our free VPN trial. Our VPN protection for Android is built on OpenVPN, the most widely used and trusted VPN protocol available. It’s the most trusted protocol because it’s open source meaning no unknown proprietary codes can do anything with your data. We also use OpenSSL libraries as well as running the whole thing over UDP ports. The result? The best speeds possible for you when using our free VPN trial. Our VPN protection for Android is built on OpenVPN, the most widely used and trusted VPN protocol available. It’s the most trusted protocol because it’s open source meaning no unknown proprietary codes can do anything with your data. We also use OpenSSL libraries as well as running the whole thing over UDP ports. The result? The best speeds possible for you when using our free VPN trial. We use the IPsec protocol for our iOS implementation which is built entirely on Apple’s proprietary stacks. The result? A super fast connection speed each time you switch on your AVG Secure VPN for iPhone. Our macOS implementation of AVG Secure VPN uses the IPsec protocol and is built entirely on Apple’s proprietary stacks. Which means that you get the best in performance and compatibility for your Mac when you connect using our free VPN trial.

What a VPN does do is make it much harder for an attacker to simply hoover up your information along with hundreds or thousands of others. That alone can help protect you from many of the large attacks and mass surveillance that have defined the last few years. Digital security, after all, is often really about economics. Spies and attackers would much rather go after the low-hanging fruit than try to crack or circumvent a VPN connection. Just remember that using security tools isn't an excuse for not also using a healthy dash of common sense.


Since it takes research to find out if a VPN service has a history of good or bad behavior, we’ve done the legwork to find the best VPN out there. In order to win our seal of approval, the service has to protect online privacy; allow you to keep anonymity; offer a good variety of locations from which to direct your traffic; offer fast, reliable performance; and provide an easy-to-use interface.
Using Wi-Fi on the Windows laptops, we timed how long it took to connect to websites, measured latency times (how long it took a server to respond), and recorded upload and download speeds with Ookla's Speedtest meter, both with and without the VPN activated. We also timed how long it took to download a large video file, both with and without VPN activation.
If VPN connections get blocked by your network because of strict network management or government censorship, TorGuard offers a “stealth” connection to avoid deep packet inspection. Specifically, TorGuard uses Stunnel (a clever portmanteau of SSL and tunnel) to add an extra layer of encryption and make your traffic look like normal, secure Web traffic. If you’re having connection issues, you can enable Stunnel with a checkbox on the main application window, but only if you select TCP from the protocol list. (Otherwise, the box is unclickable, with no explanation as to why.)
In addition to blocking malicious sites and ads, some VPNs also claim to block malware. We don't test the efficacy of these network-based protections, but most appear to be blacklists of sites known to host malicious software. That's great, but don't assume it's anywhere near as good as standalone antivirus. Use this feature to complement, not replace, your antivirus.
×