Most checkout outages are structural

Bandwidth is rarely the problem. Cabling changed during the last renovation, the switch lives inside the electrical cabinet, and the register has exactly one cable.

Checklist

  • Separate VLANs for checkout, CCTV and guest WiFi. Guest devices must never reach the checkout segment.
  • Two uplinks — wired primary, cellular backup. A checkout that stops when the fibre is cut is not acceptable.
  • Power — UPS on the checkout island, or PoE where applicable.
  • Switch placement — not in the distribution board, not in the cold room, not next to the cooking line.
  • Two ports per register — one for the register, one for the vision device.

Test it properly

Do not accept "it has internet". Do all three:

  1. Unplug the primary uplink
  2. Cut power to one circuit
  3. Reboot the switch

Then confirm checkout still completes a transaction.

Why on-device inference changes the risk profile

If recognition runs locally, a network fault downgrades you from store closed to data synced later. That single architectural choice is worth more than any accuracy improvement.