LX o ZX??

[fedecotofaja]

Hi All,

I need to connect two 3750s with 4 SFPs between two sites that are 11km away from each other....

My question is... Do I need to use Single Mode LX transceiver (but I see the maximum distance is 10km)... or do I need to use ZX transceiver? But do I need anything else?

Thank you all!

[Tom Randstrom]

The ZX SFP over Singlemode fiber is the correct choice.

If you have two fibers available for each SFP-to-SFP, then you shouldn't need any additional equipment.

[viyuan700]

Not suggesting to go against what vendor recommends, but if you have Optical Power meter and some other Transmitter at 1300nm, check the loss in your 11Km link? These figures are in general, may be you have good fiber?

Transmit power for LX is -3 to -9.5 dBm and receive levels are -3 to -20dBm. If you get the lowest Transmit power -9.5dBm,you have approx 10dBm of power. If your test shows your fiber is only consuming 5-6dBm. LX will be sufficeint but if you are getting 8-9dBm loss in your fiber then go for ZX. See the following link for above mentioned power levels.

http://www.cisco.com/en/US/prod/collateral/modules/ps5455/ps6577/product_data_sheet0900aecd8033f885.html