The deployment of the full-service access network is progressing along with the deployment of fiber-based networks. The ultimate architecture is fiber-to-the-home and business, but this will take a number of years and significant resources to be realized. Deployment scenarios for today are fiber-to-the-exchange (FTTEx), fiber-to-the-neighborhood (FTTN), FTTCab, and FTTB. VDSL is only appropriate for FTTEx, where the customers served are within close range of the central-office (CO) exchange. FTTN and FTTCab are appropriate for standalone VDSL switch deployments or as part of a next-generation digital loop carrier (NGDLC). FTTB would bring fiber directly into a building, such as a multidwelling unit (MDU) or enterprise business, and terminate at the VDSL access switch. Figure 4 illustrates the FTTN and FTTCab deployment configuration.

Figure 4. Example FTTN and FTTCab Deployment

Figure 5 illustrates the FTTB deployment configuration.

Figure 5. Example FTTB Deployment