Alien waves

Thu Jul 22 09:25:56 UTC 2021

Hi,

Alien wavelengths is a fairly old concept and more generally just
refers to running any wavelength over a DWDM system that isn't
generated by that system's own transponders.

These days it is more about leasing spectrum (Spectrum as a Service),
but that comes in several different flavours.  There is the basic "I
want access to 250GHz of C-band to light in whatever way I want",
which only tends to happen between consenting networks (e.g. in the
R&E space, or between trusted providers), or as trials due to the
risks that ytti mentioned.  That could be a single contiguous
superchannel of spectrum if you have a colourless/flexgrid add/drop
system, or 5 x 50GHz individual channels.

At the other end of the spectrum (ahem) is managed transponders.  This
is more suitable for, e.g., the submarine case.  You have guaranteed
access to a certain amount of spectrum, but the transponders go into
the fibre owner's DWDM equipment and are managed by them and you
connect to the transponder in much the same way as a traditional
circuit.  You can theoretically upgrade as newer transponders come out
that use spectrum more efficiently, or as demand requires it for a
nominal (!) fee to cover the hardware and engineering.

There are options between those models, but it's rarely a pricebook
item at the moment and will need to be discussed with the providers.
It's also usually intended for fairly large requirements.

Cheers,
Rob