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Pulling fiber to distant APs, picking multimode or single-mode.

Inside an office (up to 300 to 550 metres) multimode (OM3 or OM4) is cheaper on both cable and SFPs and plenty fast. Single-mode only wins on campus distances or if you need 25 or 40 Gbit over longer runs. The cheapest mistake: pulling OM1 or OM2 in 2026, that is dead material.

Try this first

  1. 1Measure the real distance including patch cabinets, not straight-line. Add 20 percent for bends and slack.
  2. 2Under 300 metres and at most 10 Gbit: OM3 multimode is enough and pays back on SFP cost.
  3. 3Between 300 and 550 metres or 25 Gbit ambition: OM4 multimode is the safer pick.
  4. 4Above 550 metres, or across multiple buildings on a public street: OS2 single-mode, no debate.
  5. 5Buy SFP modules together with the switch vendor, third-party works but test first, some Cisco and Aruba switches refuse third-party SFPs without an unlock command.

When to bring us in

You are crossing public ground (municipality, rail land) or fire-rated walls: this needs a certified installer, not DIY drilling, your insurer will also require it.

See also

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