In June of 2013 Comcast announced that the company was deploying new router firmware that turned customer gateways into a publicly-accessible hotspot. More specifically, updated routers would now offer two signals: one being yours, and the other being a "xfinitywifi" SSID signal providing free Wi-Fi to other Comcast users in your general area.

Fortunately, users are supposed to be able to disable this functionality if they don't want to share their bandwidth with strangers (to mixed success), but the functionality is enabled by default.

According to a new report by Juniper Research, this idea is expected to see continued traction among large ISPs looking to leverage bandwidth you pay for as a new way to market their brand and make a buck (since non-ISP customers have to pay for access in some implementations).

The problem, as we've seen, is the practice is alarming customers that had no idea this was happening.

“While most operators now allow consumers to opt-out, if they so wish, most consumers simply have no idea that their routers are being used in this way,” said research author Gareth Owen. “Given the current concerns around privacy and data security, the realisation that home routers can be accessed by complete strangers is unlikely to be viewed in a positive light.”

Companies like Cablevision have even been sued for the updates by customers annoyed that they're suddenly sharing their connections with nearby strangers. Complaints have also been levied repeatedly that this places the cost of electricity for running these public SSIDs (however modest) on the backs of paying subscribers. In Comcast's case the usage doesn't count against your usage cap (if you have one in your market), and Comcast will push more bandwidth your direction to compensate for usage.