I really don't like that you have two units in your title. A spool is a unit, although a crude one. Your title would be much easier to read if you had simply said, "Network cable can hold 1GB of internet traffic per meter."
No, you're right. It is, but your title was a little redundant.
Think of it this way. You could have said, "A planet of warehouses of pallets of spools of cable holds 1 GB per meter..." It's still a correct statement, but it's redundant. Any amount of cable holds 1 GB per meter. You don't need to say an amount at all.