A virtual private network is a secure tunnel between two or more computers over the Internet, allowing them to access one another as if on a local network. In the past, VPNs were mainly used by companies to securely link remote branch offices together or to connect traveling employees to the office network, but today they are also an important service for consumers, protecting them from attacks when they connect to public wireless networks. Given their importance, here is what you need to know about VPNs.
VPNs are good for your privacy and security
Open wireless networks pose a serious risk to users, because attackers on the same networks can use various techniques to sniff web traffic and even hijack accounts on websites that do not use the HTTPS security protocol. In addition, some Wi-Fi network operators intentionally inject ads into web traffic, which could lead to unwanted tracking.
In some parts of the world, governments track users who visit certain websites in order to discover their political affiliations and identify dissidents — practices that threaten freedom of expression and human rights.
By using a VPN connection, all of your traffic can be securely routed through a server located elsewhere in the world. This protects your computer from local tracking and hacking attempts and even hides your real IP address from the websites and services you access.
Not all VPNs are created equal
There are different VPN technologies with varying strengths of encryption. For example, the PPTP protocol (Point-to-Point Tunneling Protocol) is fast, but much less secure than other protocols such as IPSec or OpenVPN, which uses SSL/TLS (Secure Sockets Layer/Transport Layer Security). Moreover, with TLS-based VPNs, the type of encryption algorithm and the key length used also matter.
While OpenVPN supports many combinations of ciphers, key exchange protocols, and hash algorithms, the most common implementation offered by VPN service providers for OpenVPN connections is AES encryption with RSA key exchange and SHA signatures. The recommended settings are AES-256 encryption with an RSA key of at least 2048 bits and the SHA-2 (SHA-256) cryptographic hash function, instead of SHA-1.
It should be noted that VPNs introduce overhead, so the stronger the encryption, the greater the impact on connection speed. The choice of VPN technology and encryption strength must be made on a case-by-case basis, depending on the type of data that will pass through it.
The security needs of businesses are different from those of most consumers, who generally only need to protect themselves against opportunistic traffic-snooping attacks — unless they are concerned about mass surveillance by the United States National Security Agency and similar intelligence agencies, in which case very strong encryption is required.
VPNs can bypass geoblocking and firewalls
Consumers also use VPNs to access online content that is not available in their region, although this depends on how content owners enforce restrictions. VPN service providers generally run servers in many countries around the world and let users switch easily between them. For example, users can connect through a UK-based server to access restricted BBC content or through a US-based server to access Netflix content that is not available in their region.
Users in countries such as China or Turkey, where governments regularly block access to certain websites for political reasons, generally use VPNs to bypass these restrictions.
Free or paid
While companies set up their own VPNs using special network applications, consumers can choose from a wide selection of commercial and free VPN services. Free VPN offerings usually display ads, have a more limited selection of servers, and connection speeds are slower because those servers are overcrowded. However, for the occasional user, this might be enough.
Another drawback of free VPN servers, though, is that it is more likely that the IP addresses they use will be blocked or filtered on various websites: free VPN services are commonly abused by hackers, spammers, and other malicious users.
Commercial VPN services operate on a subscription-based model and stand out through the absence of download-speed throttling or data limits. Some of them are also proud not to keep logs that could be used to identify users.
A few antivirus providers also offer VPN services, and these could serve as a middle ground between free and more expensive commercial solutions, since users could get better deals if they also hold antivirus licenses from these providers. In addition, these VPN solutions already have reasonably secure settings, so users do not have to worry about configuring them themselves.
Build your own
Finally, there is the option of running your own VPN server at home so that you can connect and access the services and devices on your home network from anywhere. This is a much better option than exposing these services directly to the Internet, which is how hundreds of thousands of Internet of Things devices were recently compromised and used to launch distributed denial-of-service attacks.
The general rule is that the fewer open ports there are in your router, the better. A small piece of advice: consider disabling UPnP (Universal Plug and Play) so that poorly designed IP cameras, for example, do not punch a hole through your firewall and become available to the whole world.
Some consumer routers have built-in VPN server features these days, so you do not even need to set up a separate dedicated VPN server inside your network. Although, if your router does not have this kind of feature, an inexpensive mini-computer such as a Raspberry Pi can do this job very well.
See you very soon on Awoui for more information about VPNs! :)