Channelmania! – future proof your DWDM network topology while keeping it flexible for 1.6T

In the old days of traditional separation of IP and DWDM, there was no need for IP folks to care about much other than what they used on their routers/switches (while the transport team ran the DWDM infra). These past DWDM infra approaches for maximizing the data capacity per fiber pair went for running more and more DWDM channels with grid spacings as small as possible. This meant that grid spacings shrank from 200GHz to 100GHz and then 50GHz with some applications even going for 25GHz.
Now in the age of IPoDWDM the bandwidth per channel keeps increasing, as complex modulation schemes come into favor over ON-OFF-Keying which has been the de facto standard so far. Those increased per channel bandwidths of 400Gbps, 800Gbps and now pushing into the 1.6Tbps realm demand for larger grids to accommodate the spectrum necessary to operate such “Superchannels”. Especially the fact of coherent detection being “blind” to anything but its own wavelength has enabled interesting topologies that can omit filters altogether. Of course that comes at a cost of reduced flexibility. Which means, IP folks now will need to understand the nuances of how coherent detection works, need for larger filters for 800Gbps and higher, and how 400GHz filters (key word here being COTS) would future proof your network by not only allowing you to grow to 1.6Tbps, but also allow backwards compatibility for legacy services on 50GHz, etc.
Made by FLEXOPTIX Research - Gert and Thomas.