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New Member

GLC-LX-SM-RGD SFP for 15kms

Hi Guys,


My first post.

I have a L2 network spanning 12km, 13km, 14km and 16km.

Have purchased GLC-LX-SM-RGD and now I notice that the specs say 10km. I am commissioning next week and want to know will the SFP shoot that distance ? Will it help to set the speed on the interface to 10mbps to get the link working ?

Thanks in advance and really appreciate your comments and feedback.

- Alvin



Everyone's tags (1)
Hall of Fame Super Gold

I'm not going to take any

I'm not going to take any risks.  If you have a 15 kms link, then get the GLC-EX-SMD.  

New Member

Unfortunately I dont have the

Unfortunately I dont have the time to buy them now.

Interestingly, I was looking at another installation where the hop was 10kms and the optical loss was about 5 db (sh int g0/0/0 trans det). The optical budget for the GLC-LX-SM-RGD is about 16-17db.


1000BASE-LX/LH-3 to -9.5-3 to


-3 to -9.5

-3 to -20

2.4 (any MMF)
6 (G.652 SMF)

1270 to 1355


Optical budget is not 16-17dBm but around 10-10.5dBm a realistic. Take the lowest value of Transmit level not highest. So should be fine and you can test but these transmit values can change over time.So if you are very close not worth to take chance.


Hope the existing 10Km hop is using the same kind of SFP means working on 1300nm not 1500nm. 

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