Almost two decades ago, I worked at a network service provider who had as a customer a company that provided the technology for serving those gas pump ads.

At each gas station they had a VSAT, a router and of course the digital signage boxes on each pump.

They fed the ads to thousands of pumps via a single T1 to HughesNet in Atlanta. They’d multicast the ads, and have a local cache at each pump that would receive the stream, cache it and serve it.

It was one of the most elegant setups I’ve ever seen, and should serve as a case study in multicast for efficient bandwidth utilization across an expensive data transmission medium.