Intersection, the Alphabet-backed smart cities startup known for creating free internet kiosks for cities, is pushing to make free internet accessible in as many major cities as possible across the globe.

Why it matters: As more aspects of our daily lives — from healthcare to communication to travel — become dependent on internet-connected devices, the concept of providing internet as a public good is becoming more widespread.

• Intersection is best known for its successful transformation of NYC's 7,500 pay-phones into free internet kiosks that act as hot-spots and advertising space. It's also spreading its programs to cities like Philadelphia, Chicago, and even London.
• The catch: The program is entirely funded by advertising that the company sells on LinkNYC internet kiosks, so less densely-populated cities may be a tougher sell.

There are two things a city must have in order to be viable for free internet infrastructure from Intersection, according to the company's CEO and former advertising guru Ari Buchalter.

1. Physical infrastructure: "You've gotta have power and fiber in the grounds," Buchalter told Axios at an Axios News Shapers event in New Orleans. "Those types of infrastructure readiness is a critical factor and is a big driver of cost for the program."
2. Critical mass of people that can be exposed to ads. "We lay out of city in terms of density a factor." In NYC, for example, you have a critical mass of people exposed to advertising. Does that mean you have to be as big or dense as NYC to work? No, absolutely not. We will work figure out what other locations in cities can work in critical mass."

The kiosks also display real-time content updates to viewers depending on their city location, like sports scores, weather updates, etc. According to Buchalter, over 50% of the content displayed on LinkNYC kiosks are showing relevant NYC content to commuters, not advertising.

• The advertising that is shown is bought and sold digitally, and tends to often contextual alignments, like screens near Central Park that target running enthusiast, or screens in the business district that show financial ads.

Bottom line: There was a time just years ago when free internet was difficult to come by. Now, free internet kiosks are popping up around the country and abroad, with no signs of slowing down.