Optical MANs

Like WANs, MANs aggregate traffic from feeder networks; however, the aggregation level is less in a WAN, and direct connection of high-performance end users is more common. The fiber link infrastructure of the MAN is expected to be similar to the WAN with links made up of fiber bundles and WDM technology used on the links.

Because of the shorter distances involved, links are of higher quality, and there is more control over the topology, with rings, buses, hubs (stars), and trees being common choices (Fig. 10). These topologies have well-defined synchronization points, which enables ON service options based on time-sharing wavebands that could not be provided in the WAN.

Figure10: Physical architecture of the WDM optical metropolitan access network.

Figure 11 - A functional diagram of the MAN intelligent access node.