Using Captive Portal Networks

Public WiFi networks (guest networks), like those offered by a coffee shop or university for example, often use a captive portal network. If the desired local network requires any secondary authentication (such as a captive portal network, where you must click on a button in a web page or log in with a username and password), the MAC address of the PurpleAir sensor needs to be added to the Allowed List on the router in order to use that network.

If your MAC address has only one character within the sets of double characters, you will need to append a leading zero to make it a pair.

PurpleAir sensors will only communicate with the following fully qualified domain (FQDN) hostnames:

  • http://www.purpleair.com
  • http://api.purpleair.com
  • update.purpleair.com
  • api.thingspeak.com
  • sensors-ingest.wunderground.com
  • pool.ntp.org
  • www.googleapis.com

Outgoing ports used by PurpleAir sensors:

  • HTTP: 80
  • HTTPS: 443
  • DNS: 53
  • NTP: 123

Some organizations set up a separate or dedicated SSID to isolate them from the network. Whether you decide to do this, or simply permit the sensor to use the captive portal network, both methods work nicely.

Once the MAC address of your PurpleAir sensor is allowed on the router, we now may proceed to connect your sensor to your preferred, local or personal, WiFi network. Let’s continue to the third (and final) step of the connection guide here.