Network cabling lengths

During my day job I often have to arrange for network cabling spanning large distances within a data centre. As our data centre space is getting bigger and occupying more of the building we are hitting these problems more.

Here is a rough guide to the maximum lengths of some popular cable types. These are all approximate and may depend on type of cabling / number of patch-panels that the route goes through. To approximate the impact of going through a patch-panel you can use 10m for each patch-panel used for copper and coax. The affect on Fibre going through a patch-panel can be more.

PTT Circuits

E1 over copper 180m (normally uses RJ45 / CAT-5e cabling – but this is not the same as Ethernet)
E3 over coax 210m

Ethernet over copper

Up to 1GB CAT-5e will go to 100m (most will use CAT-6 for 1GB)
10GB CAT-6 will go to 37m (CAT-6a or fibre is normally used for 10GB)
10GB CAT-6a will go to 100m

Multi-mode Fibre (assuming 50 micron)

1GB – 550m
10GB – 82m

Single-mode Fibre

Any speed up to 10GB – 2km