messages. Another value such devices provide is that they give the SP visibility
into application level issues and therefore enhance the SPs ability to troubleshoot
the system.
Eventually, a new generation of metro-optimi zed WDM transport (often
referred to as multiservice transport platforms or MSTPs) has contributed signifi-
cantly to the recent progress in MAN WDM deployments. This WDM transport
enables elaborate optical add–drop multiplexing (OADM) architectures that trans-
parently interconnect the different MAN nodes. Moreover, such MSTP WDM
systems have scaled cost-effectively to hundreds of Gb/s, and to hundreds of
kilometers, and have significantly enhanced ease of deployment and operation,
by automated control and integrated management