PDF of this tutorialDeployment of distributed bandwidth on a fiber backbone provides the basis for migration for high-speed Internet, data, or switched digital video access. This scenario assumes the use of the existing fiber and copper infrastructure: infrastructure justified on basic telephony services. An overriding assumption is that broadcast video is served by some other previously described technique, such as HFC, MMDS, or DBS.
A simplified view of the network and the three major new elements that are required to implement a shared data service are shown in Figure 9. These basic elements are as follows:
- routing or distributed switching at the ONU
- solutions for high-speed copper (e.g., xDSL) from the ONU to the NID (Note that the solution for high-speed copper should be scalable. In other words, system bandwidth may be traded for distance.)
- a network interface device (NID) at the home to convert the high-speed copper-format signals to a format compatible with CPE
Figure 9. Elements Enabling High-Speed Digital Access in the Rural FSN
The appeal of this approach is that it utilizes the existing outside plant infrastructure, CPE, and it deloads the switch of Internet traffic. Essentially, the ONU becomes a distributed digital subscriber line access multiplexer (DSLAM). High-speed access is only provided to those subscribers who are willing to pay for the service.
