Infrastructure: Laying It All Out
Home Up Services Troubleshooting Company Policy What's On


Diagram borrowed from http://www.bcri.com/images/CATV%20NTWK.gif

The diagram above shows the difference between the coax-only infrastructure and the newer HFC infrastructure.  To implement HFC, coaxial cable from the head end is first replaced with fiber optic cable.  This fiber, known as trunk fiber because it can support a large number of users from one point to another, runs to a node (Comm. Cable).  A node is the point at which the fiber trunk and coaxial cable meet (BACP, 2007).  From the nodes on, the medium used is coaxial cable (Held).  The signal is maintained using amplifiers so it is strong enough to reach the subscriber's home.  In order for the signal from the subscriber's home to return to the head end, it once again travels down coaxial cable, through a node, and back through the fiber optic cable (Sheldon, 2007).  In other words it takes the reverse path, except it uses a different line of fiber optic cable because fiber optic cable is unidirectional (Coursaris).  Since both coaxial and fiber optic cable are being used in the transmission it is said to be hybrid.