Check optical power budget and fiber path

After the SFP choice, the optical path must be checked. The aim is a stable connection with sufficient reception power, but without overloading or saturating the receiver.

Test

Explanation

Typical measure

Transmission power of the SFP

The output power determines how much optical power is fed into the line.

Check the data sheet value of the transmitter.

Reception area of the remote station

The receiver requires a minimum power and must not be overridden.

Check sensitivity and maximum input power.

Line attenuation

Fiber length, connectors, splices and patch panels attenuate the signal.

Compare the attenuation budget of the system with SFP data.

Wavelength and fiber type

The wrong combination can cause link loss or poor reserve.

Cross-check single-mode/multi-mode and wavelength.

BiDi Direction

With BiDi, Tx/Rx wavelengths must fit crosswise.

Check complementary mating.

Check optical power budget and fiber path 1:

Note on the optical power budget

An optical connection can fail due to either too little reception power or too much reception power. Therefore, check not only "enough power", but also possible saturation.