Only one had a major difference. The PLENUM rating is for use or laid in the plenum spaces of buildings.
There is no reason to think there is any effect on long term networking.
-> MODERATOR NOTE: A similar question turned out to be by a shill and followed by the spam cable supplier. Because this has occurred more than a few times, this will be a link free discussion.
What is major difference between cat 5 , cat5e and cat5e plenum and which one is better for long term networking?

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