SFP-10G-LR minimum distance

[tkriegbaum]

Hi,

is there any minimum distance required when using cisco's SFP-10G-LR (smf) to prevent any damage on the receiving SFP+ module?

According to what I found in the web there is no minimum distance for IEEE 802.3ae! It can be used even for two meter connections.

Can anyone confirm seeing these SFP-10G-LR modules working on short distances?

I just want to avoid damaging the modules as they are very expensive but I have to use single mode fiber and the distance is only about 10-20m.

thanks,

Thomas

[Leo Laohoo]

I would say anything above 1500 feet.

[Joseph W. Doherty]

I recall (?), as you already note, there's a 2m minimum.

[Tom Randstrom · Accepted solution]

The transceiver's  max transmit power is 0.5dBm and the maximum receive power is 0.5dBm, so the minimum fiber length can be as short as required. 

[Joseph W. Doherty]

I haven't re-read the specs, but with Ethernet based technologies, there's often timing dependencies, So I'm wondering, assuming there is a 2M minimum spec, whether it might be based on some timing issue, not just on Tx to RX power.