I will be traveling for 3 weeks in London, Paris and Geneva this summer. I am a small business owner, and I will need to pay bills, run payroll and transfer funds and pay bills from my business account online. I have a Macbook and an AT&T device to access the internet, but is there a way to use a secure wifi connection while in Europe? I'm using AirBnB for my accommodations, so I will be staying at apartments throughout my stay.
If you are connecting into your company's intranet using a VPN tunnel, that is secure.
Free public WiFi's are rarely that secure the world over, but if your VPN and laptop firewall are tight, all they can see is scrambled gibberish.
If by "AT&T device" you mean you are accessing via GSM phone network, and not public WiFi, that is more secure.
If you are doing online banking, you have whatever encryption and security your bank offers as an extra layer.
Thank you for the advice!
This recent thread is related to your question, with some more information: https://community.ricksteves.com/travel-forum/tech-tips/online-banking-security