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New Member

Category 5, 120 Ohms

I am to deploy catalyst 2950 switches on a network. On examination of the cabling infrastructure, I discovered that the cabling media installed was Category 5, 120 Ohms UTP.

Does anybody know the implications of this? I am aware that the 802 standard says 100 Ohms (5% tolerance). I am afraid of the impedance mismatch causing switch port failures.

The customer has some Catalyst 3524 and 3548 switches on the network running fine on the 120 ohms cabling and they are a bit reluctant to recable the building.

Any suggestions/advice will be appreciated


New Member

Re: Category 5, 120 Ohms

Wow, sounds like somebody had some leftover ArcNet cable... *grin* Although the standard indicates 100+/-5, the 120 will work, although you will see more problems such as attenuation and you will probably be length limited. I have been forced to use this stuff once before, and as you state in your message, it works, it just isn't pretty.