Comcast just solidified long-rumored plans to launch its own MVNO cellular service. Speaking at an investor conference moments ago, CEO Brian Roberts revealed that the Comcast "network" will launch by mid-2017 and put a large focus on Wi-Fi hotspots — similar to Google's Project Fi. When away from Wi-Fi connections, Comcast's service will run on the Verizon Wireless network.

Roberts didn't announce pricing or more detailed rollout plans, only saying that Comcast will aim the mobile solution at its existing base of cable customers. That plan would give Comcast its own answer to the one-two punch that AT&T offers through its DirecTV satellite service. In AT&T's case, customers who subscribe to DirecTV get access to an unlimited AT&T mobile data plan that's unavailable to other customers.

Comcast says there are over 14 million Xfinity Wi-Fi hotspots nationwide, a massive footprint that the company would lean on as part of the upcoming mobile service. Some of those are public hotspots — coffee shops, parks, etc. — and others are actually powered by the routers in customer homes and an optional "guest mode" that shares those internet connections with people nearby.

Back in July, Comcast promoted executive Greg Butz to lead the freshly created Comcast Mobile division. The company has also signaled interest in the FCC's 600MHz auction. The Verizon-Comcast partnership runs all the way back to a deal reached in 2012, and Comcast alerted Verizon last October of its plans to sell mobile service that operating on Verizon's airwaves.

Disclosure: Comcast Ventures is an investor in Vox Media, The Verge's parent company.