Coarse wavelength division multiplexing (CWDM) is a kind of wavelength division multiplexing (WDM) technology which combines multiple signals on laser beams along the fiber. Its system utilizes non-stabilized lasers along broadband filters channel spacing of 20 nm, allowing channels up to 18. It is a cost-efficient solution in telecoms or enterprise networks. This technology can integrate with transceiver modules especially small form-factor pluggable (SFP) modules. With CWDM technology, SFP modules can have different wavelengths assigned to them from 1270 nm and 1610 nm, meeting different requirements. Those SFP modules which use CWDM technology are called CWDM SFP modules. CWDM SFP modules are hot-swappable transceiver components that are used to connect fiber cables and switches.
Cisco CWDM SFPs are the most popular compact CWDM SFP transceivers used in communications for both telecommunication and data communications. Those transceivers modules can plug into standard receptacles in Cisco routers and switches and convert Gigabit Ethernet electrical signals into a single-mode fiber-optic (SMF) interface. They can even use different wavelengths to transmit and receive signals, making fiber to fiber configuration possible. The following picture shows how CWDM SFP makes a point-to-point link. By using different channels, four channels can be transported over a single fiber strand through CWDM SFP, building a point-to-point connection.
As above mentioned, CWDM SFP modules have different wavelengths from 1470 nm to 1610 nm. Cisco CWDM SFP modules have eight wavelengths in that region. Different color markings are used to identify the wavelength to which the Gigabit Ethernet channel is mapped. The following table lists the specific colors for different wavelengths.
- Step1: Remove the CWDM SFP module from its protective packing, and verify the model of CWDM SFP. (CWDM SFP module can be identified by its label which lists the SFP module and the wavelength or by its color bar on the bale clasp.)
- Step2: Verify that the bale clasp on the front of the SFP module is closed before inserting the SFP module.
- Step3: Align the CWDM SFP module in front the slot opening, slide the SFP module into the slot, and verify that whether the connect on the module snaps into place in the rear of the slot.
Note: The dust plugs can protect the CWDM SFP module optical ports and the cable connectors from contamination. You can only remove them from the optical bore of the CWDM or from the fiber optic cable when you are ready to use the module to connect the cable.
For more information about CWDM SFP, you can visit www.fs.com.