Network cable is sold with a category label: Cat5e, Cat6, Cat6a, Cat7, up to Cat8. The number goes up, the price goes up, and the seller usually recommends the higher one.
For a home, the answer is almost always simpler than what's offered.
Category comparison
| Category | Speed | Max distance | Suits |
|---|---|---|---|
| Cat5e | 1 Gbps | 100 m | Nearly every home need |
| Cat6 | 1 Gbps / 10 Gbps | 100 m / 55 m | New in-wall installations |
| Cat6a | 10 Gbps | 100 m | 10 Gbps networks, offices |
| Cat7 | 10 Gbps | 100 m | Rarely needed, non-standard connectors |
| Cat8 | 25–40 Gbps | 30 m | Server rooms |
Note the Cat6 row: it handles 10 Gbps, but only to 55 metres. Beyond that it drops to 1 Gbps, the same as Cat5e.
What you actually need
The deciding question: how fast is your subscription, and how fast are the LAN ports on your router?
Almost every home router uses gigabit ports. That means the ceiling is 1 Gbps, and Cat5e already reaches it. Installing Cat6 adds nothing while the ports remain gigabit.
One sensible exception. If the cable is buried in a wall or run above a ceiling, install Cat6. The price difference is small compared with the cost of opening walls ten years from now. For cable lying on the floor and easily replaced, Cat5e is fine.
Far more important: solid copper or not
This distinction matters more than the category, and it's precisely the one rarely mentioned on the shelf.
Cheap cable often uses CCA: copper-clad aluminium. The material is cheaper, but conducts worse, breaks more easily when bent, and heats up when used for Power over Ethernet.
What you want is solid copper, usually marked "pure copper", "solid copper", or "bare copper" on the packaging.
How to tell if the label is unclear:
- Strip a little insulation. Solid copper is reddish all the way through; CCA shows silvery colour under a thin layer.
- CCA cable feels lighter for the same length.
- A price far below market almost always means CCA.
Cat6 CCA cable performs worse than solid-copper Cat5e. A high category doesn't help if the base material is poor.
Solid or stranded
Two construction types for different uses:
| Type | For | Characteristics |
|---|---|---|
| Solid | Fixed installation in walls or ceilings | Better conduction, breaks if bent often |
| Stranded | Patch cables from device to port | Flexible, survives repeated bending |
Using solid cable as a patch cable that's often coiled will break it internally with no visible sign outside. The symptom is confusing: the connection sometimes works, sometimes doesn't, depending on how the cable is positioned.
Common installation mistakes
Untwisting too much
The four pairs inside the cable are tightly twisted to reject interference. When fitting an RJ45 connector, the twist should be opened as little as possible, 13 millimetres maximum.
Untwisting five centimetres to make things easier to arrange is a frequent mistake, and it degrades the connection immediately.
Bending too sharply
The minimum bend radius is four times the cable diameter, roughly 2.5 centimetres for ordinary Cat5e. A right-angle bend at a wall corner changes the spacing between the wires inside and reduces performance.
Tying too tightly
A cable tie tightened until the cable deforms has the same effect. Tie it just enough that the cable doesn't shift but can still be moved by hand.
Running alongside power cable
Leave at least 20 centimetres from power cable running in parallel. Where they must intersect, cross at right angles to minimise the area where they influence each other.
Wire order at the connector
The commonly used standard is T568B:
- White-orange
- Orange
- White-green
- Blue
- White-blue
- Green
- White-brown
- Brown
What matters isn't choosing T568A or T568B, but using the same standard at both ends. Note that green and blue aren't in sequence, that's not a mistake, it's part of the design so the right pairs occupy the right positions.
Crossover cables are no longer needed. All modern gigabit equipment adjusts itself via auto-MDIX.
Testing the installation
A cheap cable tester only checks whether all eight wires are connected and in the right order. That still catches most installation errors.
A more meaningful test: connect two devices through the cable and copy a large file between them. Watch the link speed the operating system reports. If it shows 100 Mbps when both devices support gigabit, a wire pair isn't connected properly.
For a home with a subscription below 1 Gbps: solid-copper Cat5e is enough, and the difference from Cat6 won't be felt. For permanently buried cable: install Cat6, because replacing it later is far more expensive.
What deserves more attention than the category is the copper and the neatness of the installation. Expensive Cat6a with five centimetres of untwisted pairs will lose to cheap Cat5e installed properly.
Frequently asked questions
Does Cat6 make the internet faster than Cat5e?
No, if your subscription is below 1 Gbps. Cat5e already handles 1 Gbps up to 100 metres. Cat6 only gains an advantage at 10 Gbps, which isn't relevant for nearly any home in Indonesia.
Is shielded (STP) cable better?
Only in environments with strong electrical interference, such as near industrial machinery or heavy power runs. At home, ordinary UTP is adequate. STP installed without proper grounding can actually add problems.
What's the maximum LAN cable length?
One hundred metres for every category at gigabit speeds. That figure includes patch cables at both ends. Beyond it, the signal weakens and the connection becomes unstable or drops to a lower speed.
Can LAN cable run alongside electrical cable?
Preferably not closely and in parallel over long runs. Leave at least 20 centimetres, or cross at right angles where they must intersect. Power cables create fields that can disturb data cables.
