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I am looking to update my network, and would like to run 2 lengths of Cat 7 wire from my first floor office to where my patch panel is. (Planning to put a NAS down there, and run 10Gb to/from.)

The length I need is less than 50 ft (X2) and in my search for Cat 7 wire, I am not finding bulk cable less than 500 feet, which seems a waste. I find 50 foot lengths of cable with the connectors at each end.

Before I do something I'll regret, I am asking if there's any reason not to use this wire.

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    Is SFP+ (or SFP) available at both ends? Two transceivers and a bit of pre-terminated fibre could be a cost-effective option, especially considering that shafts between floors tend to have power in them, and fibre is not affected by the proximity of that sort of power. Aug 26 at 16:38
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    Cat6 will do 10GBase-T up to 60m. If your runs are shorter than this, there is no point in Cat7, only extra cost.
    – SiHa
    Aug 27 at 8:59
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    @SiHa: And harder installation. Cat6 is more flexible. Aug 27 at 12:26
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    Conduit. Run conduit. Then worry about what goes in the conduit, without needing to worry about what you might want in the future, because it will be easy in the future to change what's inside the conduit.
    – Ecnerwal
    Aug 27 at 14:13
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    Not everyone can run conduit. In England, most of our houses are not built with as much drywall as I understand houses in the USA have, so we have to chase channels I to the brick walls. Aug 27 at 16:09
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If you run cat7 into a cat5e patch panel, you will get cat5e performance, not the 10gb/s you are looking for. To get cat7 performance from your cat7 cable, you would need a cat7 patch panel, cat7 modules and cat7 RJ45 jacks. These are all harder to install than their cat5e equivalents.

Cat6a can maintain 10 Gbps over up to 100 meters but without the huge cost hike of cat7. As 50'≈15m, you are well within the distance limitation, but would be at the upper limit of the speed that copper - any copper - is capable of. Equally, you need to pair it with cat6a patch panels, modules and RJ45's to avoid bottlenecks.

As I understand it, your core requirement is fast transfer to your NAS, rather than being desperate to install cat7 for the fun of cable installation. As you need 10gb/s today, I would expect this to grow over time, and since 10gb/s is the upper limit of what copper is capable of you could quickly run out of capacity if you use copper. The speed of copper cable is limited by the fact that the cable is made of copper, whereas the speed of fibre optic cable is limited only by the kit that you connect to it - and you can upgrade that in the future much easier than you can install a new cable. Yes, Cat8 might technically be capable of 40Gbps, but that's it. When you buy a shiny new 100Gb/s network switch in the potentially near future, your copper will be useless but your fibre will keep on trucking. I should also note that 400gbps networks exist in data centres today (Cisco, Juniper), so we could see that in the consumer space in the next decade.

For high performance applications, you will not want to be limited to 10gb/s forever. For example, the Insta360 Titan can already do spherical video, often colloquially called "VR", in 11k. Insta360 have told me via email that one minute of footage can require up to 10.8 gigabytes of storage. On an ideal 1.25 gigabyte per second connection (1 gigabit = 0.125 gigabytes) it would take almost five minutes to transfer a 30 minute video file today. What about when the next thing is released that has even bigger files? With copper, you are already working on the upper limits and its stuck in your walls, so you will just have to suck up the time increase. With fibre, however, you would just upgrade your NIC & switches. The aforementioned 400 gigabit per second setup would transfer the same video file in about 6 seconds.

Positives

  • Fibre optic cable is not vastly more expensive than Cat6a.
  • Speeds can be bonkers fast.
  • Distances can be bonkers long (kilometres).
  • Electromagnetic interference is not a concern.

Negatives

  • No Power over Ethernet.
  • Installation can be a pain - optical fibre is glass so ensure that you get a pullable product.
  • Photonic kit is still more expensive.
  • Cable termination is a pain.
  • Not as widely adopted as copper in the consumer space - only your most nerdy friends will have a photonic/SFP+ NIC.

I would suggest running 4 Cat6a cables to each room in your house, alongside 2 fibre optic cables. This still allows you to use PoE, but also gives you the god-like transfer speeds where needed. For us in the more rainy side of the pond, four RJ45 euro modules also conveniently fills a double gang faceplate, though I appreciate that these might look a little unusual for all yall on the other side of said pond.

Regarding purchasing more cable than you need, never run one of anything.

  • It will inevitably break leaving you with another job. While you have got the floorboards up, you might as well throw another cable or three in there; cable is cheap, ripping the carpet, floorboards, walls etc up again is expensive.
  • In two years you will wish you had "just put one more port right there". This is why every room in my house has at least 4 Ethernet ports.

If you are putting one cable in, it takes about the same amount of effort to put 4 cables in, so you might as well put in 4. Additionally, it is always helpful to have spare cable in stock just in case.

TL;DR

I would strongly suggest dumping copper entirely for this application and going with optical fibre. It is the most cost effective and future proof option.

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    Is there a reason you don't run a 3/4" ENT or equivalent at that rate, then pull say 1 Cat6a and 1 fiber pair thru oit? Aug 27 at 11:26
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    @ThreePhaseEel If, by ENT, you mean Electrical Nonmetallic Tubing Conduit, then yes, this can help you to install fibre, but as fibre is so delicate I would not put anything else in the conduit. Also, conduit is not really necessary for copper. Aug 27 at 11:29
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    Then again, I am in England so check your local building regulations. Aug 27 at 11:33
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    Having recently crawled through the attic of our church replacing all our crappy, old, dying, poorly run CAT5 cable with two runs each of CAT6 (well laid, avoiding all the electrical cabling up there instead of being zip tied to it), I can wholly endorse the "run 2 of everything because it's easier to do it now while you're there instead of doing it all again later" philosophy!
    – FreeMan
    Aug 27 at 11:55
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    With the one drawback that more cable = more expense and church budgets are tight, while church volunteer labor is, well, volunteered... ;)
    – FreeMan
    Aug 27 at 12:02
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Use fiber instead

Cat7 is still esoteric (you need not just cabling, but Cat7 Ethernet equipment) and you'll be hard pressed to get shorter runs. Fiber is readily available and is not only easily added into existing networks, but you can easily find 10GB SFP adapters to work with most networking equipment.

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    In general, I suggest installing the best cabling within reason. I can't really describe what within reason means because that's up to the person paying and installing. If Cat7 is run, but Cat5 connectors are put on the speeds may be lower, but the connectors are much easier to upgrade later than the cable that's already been run. In a commercial environment this may not be a big deal, but in residential it may not be practical.
    – Ben
    Aug 27 at 15:52
  • Cat7 is also not even (ever going to be) compliant IIRC; you will need Cat8 to fit the full MHz spectrum required by the spec.
    – TylerH
    Sep 21 at 18:20
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Pre-terminated cables are usually stranded wire, the bulk wire is usually solid.

If you intend to cut off the RJ-45 ends and punch down the cables you may have have difficulty with the stranded wires. If you intend to use the existing termination I think either would be fine.

Stranded wires are more flexible but as I understand it are not as good as solid for signal integrity. But probably not enough to matter for this application.

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    Just to clarify. Pre-made cables will be stranded. Punch-down connectors must use solid-core, so cutting the ends off and re-terminating to keystone jacks isn't an option. You can get RJ45 'ends' for either, but you need to be careful to ensure you get the right type.
    – SiHa
    Aug 27 at 9:01
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    This. A suitability answer that I did not know. And one that kept me from a huge potential mistake. Much thanks. Aug 27 at 11:25
  • Upvoting because I was not aware that pre-terminated cables are stranded.
    – MonkeyZeus
    Aug 27 at 13:15
  • This is not always true; e.g. I bought a 200 ft solid Cat6a cable (with the intent to chop it up for two long runs). It came with ends on it, but it was definitely sold as shielded solid, not stranded. Bug again, that was for a 200 ft cable, not a bulk reel but not a shorter length that could fall into "patch cable" length. Certainly the default assumption is that cables with ends will be stranded, but if it specifically says solid it's not a contradiction for it to come with ends like @SiHa is saying. Aug 27 at 13:42
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Pre-made cables are harder to pull through walls and tight spaces than connector-less cables. If that's not a problem, then I can't see any reason not to use pre-made cables. If you buy good ones, you know the termination is good as well as the wire.

Since you seem comfortable with the idea of terminating cables yourself, you could also look at buying a 125 ft pre-made cable and cutting the ends off. It's more expensive than just getting the cable, but way cheaper than buying a 500 ft spool that you only want to use 1/5 of.

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    This doesn't address the actual question, which is about suitability. You've mostly answered a shopping question, which would be off topic.
    – isherwood
    Aug 26 at 16:26
  • I tried to focus my question on suitability, without hiding my motive. To Michael - the basement ceiling is open and I can see the wire feeding a nearby outlet, so the new hole will be okay to fish through. Aug 26 at 16:36
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    @isherwood - fair. I'm afraid my brain sort of glossed over that point, because 'cat 7' defines cable specs. If it's sold as cat 7 and no one is lying, then, well, it's suitable, because the only thing we know is the OP wants cat 7 from point a to point b. Aug 26 at 16:55

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