1000BASE-LX/LH, minimum distances

[John Trumbell]

Hi

I've inheritted a network, where there is a lot of use of single mode fiber and 1000BASE-LH GBICs. Some of them connecting to switches approximately 6 feet away. I've typically seen or used multmode fiber and the appropriate GBIC. So I've been looking for if there is a minimum distance for these LH GBICs. I know they are good up to 10KM, but if I'm connecting into another switch 6' away, is this too close?

Any help would be appreciated.

thanks

John

[Marvin Rhoads]

These are generally OK to connect via very short spans.

Per the data sheet they are rated for both TX and RX power no more than -3 dBm. So as long as TX is within spec, RX won't be overloaded.

[Andras Dosztal]

From the datasheet: "Note that all Cisco GBICs have SC-type connectors, and the minimum cable distance for all GBICs listed (MMF and SMF) is 6.5 feet (2 m)."