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An Ethernet or WiFi network which is accessible from the location of the coffee machine
Outbound access from the Ethernet or WiFi network to
<TODO>.flowcoffee.co.nz on port 443 (HTTP over TLS)
<TODO>.flowcoffee.co.nz on port 8883 (MQTT over TLS)
<TODO> on port 123 (NTP)
One, or two if the Flow Gateway will be connected via a WiFi network, AC power outlets near the location of the coffee machine (usually under the counter)
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