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New Member

Metro 1500 and MMF patch panels

Hello all, riddle me this:

I have two Metro 1500's connected between our data centers via several miles of dark fiber. I will be trunking cat. 2948's together through the channels in the Metro (one 2948 on each side of the dark fiber). The problem is the 2948's are located in different racks than the Metro gear, up to 100 feet or more away and they cannot be moved. We have fiber patch panels accross all our racks, which is 62.5 MMF. The 2948's will be using the LH/LX GBICS with -5 db attenuators, and the channels in the Metro's are High-Speed Transparent (HS-T) 100 to 1250Mbps cards.

I understand that unless I run SMF through all our racks ($$$), I 'll need mode-conditioning patch cable from the 2948 GBIC to the MMF panel. Likewise, from the panel to the Metro 1500. The SC to SC mode-conditioning cable are obtainable, but I have not found SC to mini-SC mode cond. cables. The Metro boxes have mini-SC connectors.

Given that scenario, does anyone know where to find the mode cond. SC to mini-SC cables? -or- Do I even need the mode cond. cables from the MMF patch panel to the Metro's? Has anyone run into this? I do have the SC to mini-SC SM patch cables. Any insight would be apprieciated.



Re: Metro 1500 and MMF patch panels

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New Member

Re: Metro 1500 and MMF patch panels

Up to about 1000 ft distance with LX/LH GBICs you won't need any mode conditioning cable.

New Member

Re: Metro 1500 and MMF patch panels

The Mode Cond Patch Cords are used On LX GBICS over multimode fiber. They are used to eliminate Differential Mode Delay caused by centerline dip in the fiber. Note: Most MMF made by a rep manufacture (Corning) will not have a centerline dip. Also DMD is a dispersion penalty and is Length dependent. 100 ft probably will not matter. USe a standard MM jumper and it should work. I have only seen problems when you do not use a MCPC and the length approaces 550 meters

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