Re:Is Your Cat 6 Cable a Dog? (2013)
by amluto on Tuesday January 08, 2019 @06:04PM
(#18860650)
I'd be more worried about skew. CAT5e and 6a seem to have the same delay skew spec, and I can easily imagine Ethernet PHYs that are simply unable to operate beyond 100Mbps with out-of-spec skew.
CAT7 seems dubious (not recognized at all by everyone in the industry) but has a tighter delay skew spec, so this would help.
Another potential issue would be if the PHY has an equalizer that can handle reflections due to not-quite-perfect termination at 100m or closer but has trouble beyond 100m.
Something like a 1000BASE-T-LR or something that just means "1 Gbps over CAT [whatever is needed] if properly installed at lengths up to 200m" would be quite nice. Most likely a lot of equipment would meet that spec out-of-the-box.
CAT7 seems dubious (not recognized at all by everyone in the industry) but has a tighter delay skew spec, so this would help.
Another potential issue would be if the PHY has an equalizer that can handle reflections due to not-quite-perfect termination at 100m or closer but has trouble beyond 100m.
Something like a 1000BASE-T-LR or something that just means "1 Gbps over CAT [whatever is needed] if properly installed at lengths up to 200m" would be quite nice. Most likely a lot of equipment would meet that spec out-of-the-box.