I need to connect two MDS SANs switches over dark fiber at a distance of approximately 15 miles (25km). The Long Reach SFPs are rated to 10km. Would I be able to use the CWDM-MUX8A to extend this distance? I'm thinking the answer is no since it is a passive box. Is the ONS15454 my only solution from the Cisco portfolio?
My calculations indicate that you could go at least 60km using the CWDM MUX and longer without the MUX.
I've attached a diagram to try to explain your configuration options (a picture is worth a 1,000 words).
Also, below is a link for the Cisco CWDM MUX devices with more deployment options (for future expansion options).
I hope this helps.
If you have plenty of dark fiber, then no reason to use the CWDM muxes on the end. You can connect directly to the dark fibers.
The CWDM SFPs (DS-CWDM-xxxx) support Gigabit Ethernet and 1-Gbps/2-Gbps Fibre Channel.
MDS compatibility matrix: