Disclosed is an architecture enabling premium services to be provided over
fiber to high-end users/customers. This architecture has a plurality of
nodes and a passive optical device inserted prior to one of the nodes.
The optical device allows wavelengths provisioned for original service(s)
to pass through with minimal loss, while other wavelengths provisioned
for the premium services are diverted onto a new fiber. This new fiber
may be installed at the time of the upgrade, but, sometimes, dark fiber
is available. Dark fiber is fiber that carries no optical signals.