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Live Guard I/O

EVA needs to access your devices from time to time to send printing jobs, open your cash drawer or initiate terminal payments. Which is made classically impossible by your network's firewall.

In the example below - where we only use the printer to keep it simple - we sketch the easiest situation imaginable, where EVA can directly send these jobs to your printer. The brick wall however, represents your firewall, which will block these messages from outside. To resolve this, we set up a connection between EVA Cloud and your local Watchtower.


Live Guard I/O consists of two parts; EVA Cloud, and an in-store Watchtower device. These two facets of Live Guard make sure requests between EVA and your devices are properly handled.

The basic flow that follows is simple:

Single station

  1. EVA Cloud sends out a printing job.
  2. The printing job has an StationID and the desired printer's IP-address.
  3. The printer in question has Connection type configured as Proxy.
  4. EVA Cloud knows it should connect to the corresponding OU's Watchtower device.
  5. EVA Cloud uses that Watchtower to search for the printer's IP in the store network.
  6. When found, the printing job is sent straight to the printer.

Multiple stations

Obviously, a store can have multiple stations, but this does not mean you would need multiple Watchtower devices. Since EVA Cloud just uses the Watchtower to search for the printer's IP-address within the store, one Watchtower device can cover all your Stations.