Cablevision offers broadband internet and TV, in addition to home phone services, through their hybrid fiber coaxial (HFC) network.
HFC networks offer internet to consumer residences by running a fiber optic connection to a local neighborhood node and then finishing the “last mile” of the connection using coaxial cable.
A HFC network infrastructure is common with companies that historically specialized in “cable TV” service, since they had already spent the high up-front cost to install coaxial cable to individual houses.
Optimum has reportedly begun to roll out DOCSIS 3.1 in some areas, which will allow them to offer faster broadband options depending on the local internet infrastructure. DOCSIS is the protocol used to send data over coaxial cable, and DOCSIS 3.1 can support multiple-gigabit speeds in ideal setups, rivaling true “fiber” connections.