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New Member

DWDM GBIC connectivity

Our company has two sites (200 Km between them) each comprised of one Catalyst 4506. Can we use DWDM GBIC for a direct connectivity using fiber optic (like the ZX GBICs)or we need OADMs ?

Thanks in advance for your help

New Member

Re: DWDM GBIC connectivity

No chance for a direct connectivity at 200 km! ZX

GBICs have a power budget of around 23 dB, and 200

km of SM fiber with a loss of 0.20 - 0.25 dB/km

gives you a loss in the fiber alone of 40 - 50 dB.


Re: DWDM GBIC connectivity

Steinar is right, there is no way you are going to get a usable signal across 200km distance without some help along the way.

You need one or two signal regeneration points on that fiber path, depending on the type of SMF you're using and where you can geographically place the regen point(s). Typically co-locating in the nearest telephone company central office or communications carrier's point-of-presence that's within range of your signal's origin is what you would look for.

Either use the least expensive switch you can at each point along the way, and put ZX or DWDM GBICs in the 1550nm wavelength region to boost the signal to the next point. Or, you could use erbium-doped fiber amplifiers (EDFA) to boost the signal along. Cisco even offers one, here's a link to it:

Cisco ONS15501 Erbium Doped Fiber Amplifier

Not sure what your application is, but if you're looking into DWDM GBICs versus ZX GBICs, then you may want to consider the EDFA which will amplify across several wavelengths in the 1550nm region, vs. the ZX-GBIC-and-switches approach which is just one GbE signal being rebroadcast by the switch.

Hope this helps.