Hybrid Fiber-Coaxial network (HFC), also called coaxial network, is the telecommunication network architecture that combines fiber cable and coaxial cable to carry broadband content to users.
Coaxial cable was invented by Oliver Heaviside, who patented the design in 1880. The hybrid network was globally used by cable television operators until the 1990s. Since then, the HFC architecture evolves to Next-Generation Access (NGA) networks, supporting also internet, telephony, and multimedia services.
The network supports the transmission in both directions and the largest optical distance between the cable modem termination system and the farthest cable modem is 160 km.
Legacy HFC DOCSIS 3.0 cable networks use a tree topology with the analog transmission in an RF bandwidth 1 between 50 and 1,000 MHz, serving customers through a shared physical environment, with a downstream capacity until 1.2 Gbit/s. The 3.1 and the new DOCSIS 4.0 allows a downstream of 10 Gbit/s.
Benefits of Coaxial
While fiber is trendy in greenfields, coaxial still the most rational and economical option for brownfields, because the technology will continue to involve up to 10Gbps connectivity in the in the next years.
Besides the good bandwidth, the coaxial network allows a great channel capacity, can be easily modified and has noise immunity due to the low error rate. Another benefit of the use of coaxial cables is the electromagnetic field carrying the signal exists only in the space between the inner and outer conductors, this means the coaxial cable can be installed next to metal objects without losing power, unlike other types of transmission lines.