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Through the use of each of these technologies, the network is able to take advantage of the benefits and minimise the impacts of the limitations inherent to each.

Optic fibre provides the ability to cover reasonably long distances within minimal amplification and regeneration. However, due to the nature of this technology, and the cost and size of Optic Mux-Demuxers this technology is rarely used to connect the exchanges directly to customers.

Instead, the optic fibre terminates at a network element referred to as a "Gateway". A gateway contains at least one (normally two) optic transcievers and transcievers allowing the signal to transition into a coaxial cable network.

Coaxial cable provides considerable bandwidth capacity, whilst also allowing for the signal to be extracted and inserted ("tapped") with minimal interference to any customers or equipment downstream (further down the cable, away from the Gateway). It also requires far less expense with regards to the equipment required to receive and transmit these signals (as the signal is RF in the coaxial cable). The limitations of this system are that the signal needs to be amplified often to achieve the coverage required, and (due to its carriage through coaxial cable) it is susceptible to interference from external Electrical interference.

Carriers employing an HFC Network have a number of options available regarding the use of the bandwidth available through this system.

• Some use 100% of the bandwidth for broadcast signals.
  • This is normally done for simple Cable TV Networks or other products which will operate on a simplex network.
  • Some asymmetrical services (such as broadband internet) can be operated on a simplex HFC network, using a conventional telephone line to provide the "reverse path".
• Some use a small proportion of the bandwidth to create a "reverse path".
  • This allows monitoring of equipment attached to the network, providing faster identification and diagnosis of faults.
• Some use a larger proportion of the bandwidth to create a "reverse path".
  • This allows products which require a duplex network to operate. Including broadband internet, telephony and interactive television.

HFC Networks are employed by a number of telecommunications companies.