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We have already purchased 500ft Cat7 Ethernet cable. We wanted the high-quality cable running through our walls to be future-proof and to ensure we get Cat7 speeds (at least in the future). However, we seem to be having trouble finding Cat7 keystone jacks, while Cat7 cable and Cat6a keystone jacks are common.

I have also found sellers that say Cat6a keystones are suitable for Cat7.

Are they? Is this what we've been missing, that we're supposed to use Cat6a keystones with Cat7 cabling? Will this reduce the signal at all? Can we still get full Cat7 speeds this way?

Edit: Do you think I would experience any issues using Cat7 cables with Cat6a RJ45 connectors, for 10 Gbps speeds?

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No, you won't get the 25Gb Cat 7 bandwidth with Cat 6a termination. For 25Gb speeds you need to terminate with GG45 (GigaGate45), ARJ45, or TERA, but not RJ45.

I think you should use 6a termination so you'll get 10Gb, but if 10+Gb becomes available in the future you can replace the terminations if needed.

GG45 is a product sold by Nexans that is backwards compatible with RJ45 at 10Gb speeds. ARJ45 is the ISO standard non-brand name that is similar to GG45 but might be easier to find. TERA is a product sold by Siemon, but isn't backwards compatible with RJ45, so it's not as common.

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    Are you saying that there will never be true Cat7 RJ45 connectors, or at least that they don't exist right now? So we can only get up to 10 Gigabit through Cat6a RJ45? We only want RJ45. Commented Jan 8, 2018 at 4:19
  • Correct. The 6a RJ45 connectors pins are physically too close together to operate at Cat 7 speeds. GG45 is backward compatible with RJ45 ports, but there are special edge pins that get used instead when inserted in a Cat 7 port. It appears that RJ45 is done after Cat 6a.
    – Dotes
    Commented Jan 8, 2018 at 4:30
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    Are they backwards compatible both ways? Can I have GG45 male in RJ45 female as well as RJ45 male in GG45 female? (obviously only expecting up to 10Gbit Cat6a speeds) Commented Jan 8, 2018 at 4:36
  • Do you think I would experience any issues using Cat7 cables with Cat6a RJ45 connectors, for 10 Gbps speeds? Commented Jan 8, 2018 at 5:34
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    Yes, GG45 and RJ45 are backwards compatible both ways for 10Gb speeds. You won't experience any 10Gb issues using Cat 7 cables with Cat 6a RJ45 connectors. Install RJ45 everywhere for 10Gb speeds, and in the future you can change over to GG45 as you get 25Gb network equipment. If you are expecting to need 40Gb speeds between anything, then skip 7a cable and install Cat 8 cable (or at least run conduit so you can pull Cat 8 in the future.)
    – Dotes
    Commented Jan 8, 2018 at 15:32
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No. Cat 7 has different connector requirements (emphasis mine)

The cabling can support frequencies of up to 600 Mhz. Cat7 offers extensive shielding to reduce signal attenuation and is relatively stiff in comparison to previous generations of cabling. The shielding needs to be grounded and Cat7 also requires special GigaGate45 (GG45) connectors.

While Cat6a comes close, Cat7 supports higher frequencies. As such, the Cat6a does not have the shielding support the 600 Mhz signals Cat7 does. Note the differences between this GG45 and a standard RJ45

enter image description here

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  • Do you think I would experience any issues using Cat7 cables with Cat6a RJ45 connectors, for 10 Gbps speeds? Commented Jan 8, 2018 at 4:33
  • @AaronFranke If you're using Cat7 equipment, probably. Again, Cat7 uses 600mHz, while Cat6/6a uses 500mHz. I wouldn't risk it. I'd hate to explain to someone that you spent all this money on bleeding edge equipment that can't be fully utilized because someone skimped on the connectors. Remember, these new wire standards are all built around shielding to cram more signal through the same wires.
    – Machavity
    Commented Jan 8, 2018 at 4:37

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