Hi there!
This time, I will share with you some knowledge points about WDM.
Colored:
Colored add/drop ports(fixed wavelength) have the advantages of lower insertion loss and lower cost. If new wavelengths need to replace the existing wavelengths, a site visit is necessary to connect the line card/OTU colored port to the matching add/drop port.
On an ASON network, the services can be rerouted only on the same wavelength, so the wavelengths may be blocked.
Colorless:
Colorless add/drop ports(tunable) allow remotely provisioned reconfigurability of the ROADM. However, the OTU/line boards must be installed in the subrack in order to automatically provision new services. If the OTU/line boards are not physically present in the subrack, a site visit is necessary to install the required boards for the new services.
On an ASON network, if a wavelength-tunable OTU or line board is used in the colorless scenario, service wavelengths can be flexibly converted during rerouting to avoid a wavelength congestion.
Directioned:
In a directioned scenario, the current path cannot be adjusted flexibly. If the current path must be adjusted, a site visit is required to adjust the fiber connections for the network.
A directioned scenario applies to non-ASON networks.
Directionless:
On a non-ASON network, the current path cannot be automatically adjusted in the directionless scenario. When services are adjusted or the protection path is used in case of a faulty working path, manually configure optical cross-connections to achieve flexible service grooming.
On an ASON network, the rerouting function automatically finds a path and automatically creates an optical cross-connection.
That's all, I welcome everyone to leave a message and exchange in the comment area!
Thank you！
