Transceivers
- Most transceivers are stamped or molded to show which port is transmit and which port is receive:
Polarity Examples
Juniper QFX5100/QFX5110
- On Juniper QFX5100 and QFX5110:
- Even ports (top row) will have the transmitter on left, receiver on the right
- Odd ports (bottom row) will have the receiver on the left, transmitter on the right
*This photo also shows attenuation, more notes on that at Optical: Power and Calculating Loss on a Fiber Span
ASR920
- On the Cisco ASR-920-4SZ-A:
- Odd ports (top row, ports 3 and 5) will have the transmitter on left, receiver on the right
- Even ports (bottom row, ports 2 and 4) will have the receiver on the left, transmitter on the right