Wi-Fi is convenient, but the foundation of a reliable network is still the cable. Well-done cabling lasts many years, outlives several generations of routers and access points, and frees the Wi-Fi for devices that actually move around. The choices are few, but they need care, because redoing cables inside walls costs far more than laying them properly the first time.
Cable categories
Copper Ethernet cables are classified by category, which indicates the frequencies supported and therefore the achievable speeds. The standard maximum length of a link is 100 metres, patch cords included.
| Category | Speeds supported at 100 m | Notes |
|---|---|---|
| Cat5e | 1 Gbit/s, 2.5 Gbit/s | Enough for many homes, but now outdated for new installs |
| Cat6 | 1 Gbit/s, 2.5 and 5 Gbit/s; 10 Gbit/s over shorter runs | A good compromise for homes |
| Cat6a | 10 Gbit/s at 100 m | Recommended for new installations and offices |
| Cat7 / Cat8 | Higher, over short runs | Specific connectors and uses, rarely needed at home |
For a new installation, especially inside walls, Cat6a is the most future-proof choice: the extra cost over Cat6 is small compared with labour. Cat6a is, however, thicker and stiffer, and needs conduit of adequate diameter.
Real copper, not copper-clad aluminium
Be wary of very cheap CCA (Copper Clad Aluminium) cables, aluminium coated with copper. They have higher resistance, heat up more with PoE, break more easily and do not meet category standards even when the packaging claims they do. Choose solid copper cables, labelled "solid copper" or "pure copper".
Solid and stranded cable
- Solid (single-wire) cable is for fixed runs inside walls, terminated on wall sockets or patch panels.
- Stranded cable suits patch cords between socket and device, which are handled often.
Crimping a plug directly onto a solid cable coming out of the wall works, but it is more fragile. A wall socket with a patch cord is more reliable and tidier.
Planning network points
- Run every cable to a central point, a small cabinet or niche housing router, switch and NAS. This is the star layout of structured cabling.
- Plan at least two points in every room that might hold a TV, desk or console.
- Run a cable to the ceiling or high on the walls at spots suited to access points.
- Leave a draw wire or pull cord in the conduits for future additions.
- Label both ends of every cable with the same code and record the map.
Switches: managed or unmanaged
An unmanaged switch connects devices and nothing more: no configuration, no extra features. It is perfect for adding ports near the TV or desk.
A managed (or "smart") switch instead lets you configure VLANs, check port status, limit traffic, monitor via SNMP and enable protections such as DHCP snooping. It becomes necessary when you want to separate networks.
Also consider:
- port speed: 2.5 Gbit/s multi-gigabit ports are now common and useful for recent Wi-Fi access points and NAS units;
- faster uplink ports, to connect the switch to the router or another switch without creating a bottleneck;
- noise: many rack switches have loud fans, ill-suited to a cabinet at home.
Watch out for loops: connecting two ports of the same switch, or two switches with two cables, creates a loop that can paralyse the network with a broadcast storm. Managed switches offer the Spanning Tree protocol to prevent it.
PoE: power over the network cable
With PoE (Power over Ethernet) the switch powers devices through the same cable that carries data. It is ideal for ceiling access points, cameras and VoIP phones: no scattered power adapters, and you can reboot them remotely by switching the port off.
| Standard | Power at the switch port | Typical uses |
|---|---|---|
| 802.3af (PoE) | 15.4 W | VoIP phones, simple cameras |
| 802.3at (PoE+) | 30 W | Access points, pan-tilt cameras |
| 802.3bt Type 3 | 60 W | High-end access points, small devices |
| 802.3bt Type 4 | 90 W | High-power devices |
The device receives somewhat less than the stated power, because part of it is lost in the cable. Two checks before buying:
- the switch's total PoE budget, the maximum combined power it can deliver across all ports;
- that the switch uses standard PoE and not a fixed-voltage "passive" variant, which can damage incompatible devices.
If you have just one PoE device, an injector between a normal switch and the device is a cheap solution.
In short
- For new installs, especially in walls, choose solid-copper Cat6a; avoid CCA cables.
- Use solid cable in walls with sockets and panels, stranded cable for patch cords.
- Run cables to a central point, plan access point locations and label everything.
- Managed switches are needed for VLANs and monitoring; beware of network loops.
- With PoE, check the standard, the total budget and the power your devices require.
