Joining the Free Wi-Fi at your local restaurant or department store can be a very nice convenience. But did you ever stop and think what others can see or learn about you as you join it?
Your Hostname and MAC Address
If you have given a hostname to your iPhone using personal information such as your first and last name (for example, “Mike’s iPhone”) most networking equipment can see that name. By sticking with a more generic name (such as just “iPhone”), it will be more difficult to pin-point a user associated with the device.
The MAC address (or Media Access Control) is linked to every network adapter. This is usually brand specific, identifying your device by the company that manufactures. So even if viewing a device under a hostname like “Mike’s Android, you won’t be fooling many people. The MAC address will still establish that you are using an iPhone.
Be careful when you’re surfing websites on free Wi-Fi! Most routers can see individual internet traffic by device. Most websites are Secure (using Https://) because they can mask your traffic; but routers can still view the top-level domain. For instance, if you visited Amazon and purchased a pair of slippers, the router would be able to see that you went to Amazon, even though what you searched for would still be hidden.
Here’s an example of what might appear on the router: https://Amazon.com/#&*(@).
Your EXACT LOCATION and Length of Time There
With WiFi beacon technology, you can precisely locate a user if there are 2 or more wireless devices giving out signal. This is done by triangulating your device’s location based on multiple wireless access points. The more wireless access points a business has, the more precise the location of the person will be. For example, most users spend a lot of time on a certain brand’s shoe aisle. They can use this data to promote that brand on other mediums.