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NET-C0179 · Physical Layer, Cabling & Data Center

Cat5e vs Cat6 vs Cat6a vs Cat8

Pick a copper category for one run, from length and speed, not from the newest name.

Updated 25 October 2026 · Comparison

This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.

What this hour is for

Cat5e, Cat6, Cat6a, and Cat8 are cable categories with different expectations of speed and length. The selector drafts a category from a speed and a length you type. The distance reference is a limit, not a dare to exceed it.

A short run can be a lesser category. A long run at a higher speed may not. Write the length you will actually pull, including the patch cords if they count against the limit.

Shielding and installation quality matter as much as the printing on the jacket. This page does not certify a cable. It records the choice.

Fiber is the other comparison when the length is past copper. Do not force copper because the tray is familiar.

The change you can finish

Apply nothing during the writing of the note. When the lab window opens, it is one change on the device named in the ticket. Read the draft, then the device, then decide.

Rollback is the file or the revision you saved first. You do not invent a rollback after the only copy is gone.

  1. Write the length and the speed.
  2. Draft a category.
  3. Include patch length if it counts.
  4. Say why a higher category was rejected or chosen.
  5. If the length is past copper, stop and use the fiber page.
  6. Do not order the building from one run's draft.

Mistakes that outlive the command

Cat5e vs Cat6 vs Cat6a vs Cat8 goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.

Decisions to write down

One decision for Cat5e vs Cat6 vs Cat6a vs Cat8: Length and speed are written. The category matches them. The limit was respected. One run is the example. And no plant was ordered.

Checks before you call it done

Confirm this before you call the change done: The run is identified. The category is written. The length includes the parts that count. Fiber was considered if the run is long. And nothing was purchased from this page alone. If one of those fails, stop.

Length and speed pick the category.
A limit is not a suggestion.

Before you leave the device

Cat5e vs Cat6 vs Cat6a vs Cat8 ends when the hostname on the device matches the hostname in the ticket. If it does not, you are on the wrong box. Stop. A command that succeeded on the wrong box is not progress.

The draft stays a draft until a person has read the names in it. A generator does not log into the device and does not know which interface is the uplink. You delete a line that names a device, a zone, or a prefix you did not write down.

0.0.0.0/0 is not kept because a sample included it. A source you can say is the source you keep. 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. They belong in the note. They are not prefixes you type onto a production device because they appeared in a draft.

prompt-for-this is a reminder that a secret is missing. It is not a password, a key, a community string, or a pre-shared key you save in the ticket or in git. The real secret stays in the store.

One change is the window. A VLAN and a routing protocol and a VPN do not share it. If two things move and the result is wrong, you will not know which one did it. The next feature waits for its own page.

If the same step fails twice, stop for the day. The failure is the result. Adding a forum command beside a half-applied config produces a device nobody can rebuild. Restore the copy you took first.

A second person reads the device name and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the device alone.

This page is a planning guide. It is not a vendor manual, not an official standard, and not a permission to touch a network you do not administer. The pillar guide owns the wider design. This page owns one lab proof.

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