PDF of this tutorialThis all-fiber access system called a PON is intended for residential applications for Internet and other services access. The architecture shown in the top of Figure 9 has fiber from the service node to the optical splitter. At the splitter, multiple fibers fan out to terminate on a single-home ONU. The ONU then splits out to provide individual service to the home. There are many schemes for technical realization of PONs, the more interesting one consists of wave division multiplexing (WDM) for up to 16 ONU drops from the optical splitter. WDM techniques would again be used in the upstream direction to realize a highly secure point-to-point PON architecture.
Figure 9. Pure Fiber Access—PON
As it is all fiber, PON has many advantages. All fiber yields a robust outside plant that has low maintenance costs associated with it. All fiber point-to-point architecture allows for secure transmissions and broadband service applications.
The PON architecture represents the target wireline architecture because of its versatility and evolution-proof capabilities. However, initial costs of PON systems are still higher than most all of the other alternatives discussed within this tutorial.
