Tag Archives: VPN

Beware of public Wi-Fi

Because of the mobile equipment you use, the scope of your workspace increases beyond your office.

I’ll walk you through a normal business trip and your re-entry back into your personal life…

Let’s start with you at your office on a Thursday morning; your phone, tablet, and/or laptop are connected to either your corporate wired or wireless network:

  • You get on the train to the airport and connect to the train’s Wi-Fi
  • At the airport terminal and then on the plane you connect to each of their Wi-Fi networks
  • Your taxi or Uber on the way to the hotel doesn’t have Wi-Fi, so your mobile phone is connected to 4G LTE, but a 4G LTE network is NOT a private network segment, it is one shared with other subscribers of (for example) Verizon
  • At the hotel that night, you’re on their network
  • Next morning, you do some pre-meeting preparation at a Starbucks while on their Wi-Fi
  • During your customer meeting you’re on their network
  • Because you need to do some work on your laptop in the taxi on the way back to the airport, your laptop is connected via your AirCard, but AirCards use 4G LTE data connections like mobile phones and so it is NOT a private network
  • When you’re back home Friday night, you connect to your home network
  • Saturday you watch the game at a relatives’ house and connect to their Wi-Fi
  • Sunday you go the gym, and connect to their network

Before, during and after your trip, in all these contexts, you are sending and receiving confidential information over a public network.

So what? You do this all the time and it’s great that you have instant access to information. The problem is that hackers on those public networks can observe your behavior unless you protect yourself with VPN.

VPN stands for Virtual Private Network and it is not the same thing as a firewall, you have to log into a VPN. Businesses usually host a VPN for their mobile workforce and VPNs can be subscribed to by consumers.

Before I detail the benefits of using VPN, here is the information that is potentially visible to others connected to the same network as you:

  • The URLs of web pages you visit in a browser and the URLs of web pages visited behind-the-scenes as you use mobile apps and client applications
  • Web form data you enter… some web pages you visit, like news and Wikipedia articles, respond with static content that is not influenced just because you visit those pages. However, a lot of web pages you visit give you the opportunity to send them form data and tailor the content with which they respond
  • The static page content or the page’s response to your form data

Here is what is visible and what is hidden:

Effect of using VPN
VPN enabledVPN enabledVPN not enabledVPN not enabled
HTTPS pageHTTP pageHTTPS pageHTTP page
siteHiddenHiddenVisibleVisible
form dataHiddenHiddenHiddenVisible
responseHiddenHiddenHiddenVisible

Without VPN enabled, the situation gets complicated. It depends upon whether the page’s owner servers you the page via HTTPS or HTTP (the “S” in HTTPS stands for “secure”). I’ll show you some examples in a second, but even if the page you visit is served to you via HTTPS, without VPN enabled, the fact that you are visiting that page is visible to others connected to the same network as you.

and when you visit a page served to you via HTTP, without VPN being enabled, everything is visible.

Services which believe they are processing your confidential information often use HTTPS to protect you, which is good. However, a service’s idea of what information is confidential to you and your idea of what is confidential might be different. Therefore, avoid this confusion by enabling VPN when doing confidential network activity while connected to a public network.

Here are examples of pages served only via HTTP, meaning that without VPN the form data I send and the response I receive is visible to anyone else on my same network:

So the next time you connect your mobile device to a public network, think about that unseen person in an another room at your same hotel, your roommate at home, your brother-in-law in his basement while you’re visiting your sister, your kids’ friends during a sleep-over, and the AirBnB renter in your spare room.

However, when you use that public network to connect to a VPN server, all that information that the hacker was able to see is now hidden from them, you’re connected to the VPN network and your access to the internet is then made from the VPN network, not from the public network.