10G BIDI SFP+ ZR+ 1490Tx 1550Rx 100km

Q: SFP-10G-LRM vs. SFP-10G-LR 10Gigabit Optical Modules: How to Choose?

A: The SFP-10G-LR 10Gigabit optical module is suited for long-range communications extending up to 10 kilometers, useful in interconnecting buildings across large campuses and in constructing Metropolitan Area Networks (MANs). The SFP-10G-LRM 10Gigabit optical module, besides supporting multimode transmission as mentioned, also accommodates single-mode transmission where optical saturation doesn’t occur. The SFP-10G-LRM can reach distances up to 300 meters. Therefore, for transmissions within 300 meters, the SFP-10G-LRM is a more economical and efficient solution. For distances between 300 meters and 2 kilometers, the SFP-10G-LRM2 is a better fit than the SFP-10G-LR, given its lower cost within the same transmission range. For spans between 2 and 10 kilometers, the SFP-10G-LR is the optimal choice.

Note: The SFP-10G-LRM2 has a maximum transmission distance of 2 kilometers over single-mode fiber, suitable for short-range LAN connectivity.

Q: Can XFP optical modules be interconnected with SFP+ optical modules?

A: Since XFP optical modules and SFP+ optical modules share the same transmission rates (both at 10Gbps) and wavelengths (supporting 850nm/1310nm/1550nm), they can coexist within the same Ethernet network. This implies that XFP modules and SFP+ modules can be interconnected provided their parameters match, for example, a 10G XFP module with a wavelength of 1310nm can be linked with a 10G SFP+ module of the same wavelength. However, it’s important to note that XFP modules are not interchangeable with SFP+ modules.

Q: Can 10G SFP+ optical components operate on 1G SFP ports?

A: Can a 10Gb SFP+ operate at 1Gb speeds? The answer depends on the context. You may need to throttle down the rate of a 10G SFP+ transceiver on your switch, but it’s not a practice that is generally encouraged. Economically speaking, if you have a 1G switch and a 10G switch, and you connect them using two 10G fiber transceiver modules, you’d end up with a 1G network connection! Since a 10G port can utilize a 1G module without loss of functionality, it begs the question: why not simply replace the 10G module with a 1G module instead?

Figure 3: Connection between 10 Gigabit Switch SFP+ Port and Gigabit Switch SFP Port