OPTICAL LINK — COMPATIBILITY AND POWER RECORD
Use one sheet per direction and repeat for the reverse path. This simplified budget applies
only when transmitter and receiver specifications use comparable power definitions; apply
the actual standard's penalties and limits.
Endpoint A host / line card / port / software / module order code:
Endpoint B host / line card / port / software / module order code:
Compatibility matrix URL / date / required port mode / rate / FEC:
Optical standard / TX and RX wavelengths / complementary pair if needed:
Fiber type/grade / route / length / connector and polarity map:
Minimum TX (dBm) / receiver sensitivity (dBm):
Available loss budget (dB) = min TX - sensitivity:
Maximum path loss including specified penalties (dB):
Weak-signal margin (dB) = min TX - max loss - sensitivity:
Maximum TX (dBm) / minimum path loss (dB):
Maximum predicted RX (dBm) = max TX - min loss:
Receiver maximum operating input (dBm) / overload margin:
Required design reserve / attenuator tolerance if applicable:
Illustrative: -3 - (-15)=12 dB; 8 dB loss -> -11 dBm RX, 4 dB margin. 0 dBm TX with 1 dB
loss -> -1 dBm RX, exceeding an assumed -3 dBm maximum by 2 dB. A nominal 3 dB attenuator
reduces weak-signal margin to 1 dB before tolerance; a 2 dB reserve would fail.
DOM support / TX-RX readings / thresholds / temperature / timestamp:
Symptom / error counters / link state / saved logs:
One changed item / result / fault followed which item:
Never look into fiber ends or ports; follow the equipment's handling procedure.

Yenra | Updated September 10, 2026
Article and explanation: https://yenra.com/pluggable-transceivers/

Source references (use exact equipment/material documents for actual work):
https://tmgmatrix.cisco.com/
https://www.juniper.net/documentation/us/en/hardware/cable-site-planning/topics/task/calculate-fiber-optic-power-budget.html
https://www.cisco.com/c/en/us/td/docs/routers/asr903/software/guide/chassis/17-1-1/b-config-guide-xe-17-1-1-asr900/digital_optical_monitoring_for_transceivers.html
https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9200-switch-stack/222738-troubleshoot-fiber-links-on-catalyst-900.html