Typically, CWDM is a technology used to transport multiple signals between distant locations over single fiber connections. This leverages the utilization and therefore the relative cost of the long distance fiber cable links. However, with HDTV and the increasing bandwidths required for video production (3Gbit) and new 3D markets rapidly evolving (which makes extensive use of 3Gbit SDI in the production environment) we see fiber connectivity increasingly taking the place of traditional copper (electrical) connections within facilities.  As this evolution continues and more and more dedicated unidirectional “point to point” fiber connections are consumed, then an “in house” CWDM solution is the logical next step to better utilize the facilities existing fiber cable assets.

CWDM Fiber Primer: http://www.lynx-technik.com/fileadmin/fy_typo3_distribution/lynx-assets/pdf/applicationNotes/The-CWDM-Fiber-Primer-Rev2.pdf