Verizon Communications Inc. plans to start selling home broadband service over its wireless network in late 2018, a move to challenge the cable industry’s grip on Americans’ internet access.

Verizon said Wednesday it would sell high-speed internet access in three to five cities, starting in Sacramento, Calif. The cities are all expected to be outside Verizon’s existing landline footprint in the Northeast, where it sells high-speed fiber-optic internet called Fios. The company said more details, such as its price, would be unveiled later.

The wireless giant will use fifth-generation, or 5G, technology, which is capable of delivering significantly faster internet speeds than existing 4G technology, also known as LTE. Customers will likely have to place a box in their windows that will convert Verizon’s wireless signals into Wi-Fi inside the house.

If the technology works, and users adopt it, it could result in more competition in the home internet market. Many Americans only have access to one broadband provider, often a cable company. By selling outside its existing footprint, Verizon could enter cities as a new competitor.

Comcast Corp. is the country’s biggest broadband provider with about 25 million subscribers, followed by Charter Communications Inc. with about 23 million, according to Leichtman Research. The duo account for almost half of all U.S. broadband connections.