I’m installing a cable modem and have to making a run of roughly 45-ft. Should I make it:
(a) 45’ of coaxial cable from cable split to modem, with a 1’ USB connection from modem to computer, or
(b) 6" coax cable from cable split to modem, with a 45’ ethernet connection from modem to computer?
Is coax or ethernet better at spanning this distance, or is there no difference? What about degradation of cable signal if I split the signal more than once?
Go with the coax (preferably RG-6 or RG-6QS), the reason being is that sort of cable is well designed for its purpose, whereas long runs of CAT-5 or CAT-5e cable can pick up bandwidth-robbing noise in some circumstances. Take the run off the first split from the dropline from the streetside pole.
Related, but [ hijack ]:
What’s the deal with ratings for ethernet cables? I’ve seen CMR and CMX. I’m wanting to buy some Cat-5e, but I’m wondering about the ratings.
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“May not”? That implies that it can, but isn’t permitted to… my questions are: Who rates this? Is CMR a higher quality cable with more shielding? If I knowlingly used CMX cable in a commercial installation, would I get in trouble? Would the cable police come looking for me? Do they perform audits or something?
Well, cat 5 cable is certified to run at least 100 meters, so 45 feet shouldn’t theoretically be a problem. The problem arises during bad installation. You can’t have bends smaller than a 5 inch diameter (no kinks), and it is common to pick up interference from florescent lights.
How familiar are you with cable termination? Both can be a bit tricky if you don’t know what you are doing. Purchasing a 50 ft length of terminated cat 5 might be the better route as long as you are careful in the installation.
As far as I know, CMX and CMP differ only in the material used for casing. CMX (non-plenum rated) uses a PVC coating that is cheaper to make. CMP is what’s called plenum-rated cable (a plenum is the space above the ceiling, by the way, that’s used for ventilation ducts and running wire in a lot of offices). The reason you have to use plenum-rated for commercial jobs is because its casing is not made of PVC, and if there is some kind of a fire it will not give off toxic fumes as it burns which could be spread through the ventilation ducts, as PVC is liable to do.