Send downlink directly to device

Hi,

I am working on an asset tracking project using the Nordic nRF9160 chipset that is going to be spending the majority of its time in an idle/standby state on eDRX intervals of 2.7 minutes, waiting for a command to be sent from the user.

My goal is to make the most of the module’s efficiency by communicating in a way that doesn’t require the device to subscribe to an HTTP server and consume tons of power checking for commands every time it cycles.

I know circuit switched SMS is one way to do this, but I have heard there are reliability issues at times when devices are unreachable during eDRX.

I’m going to test SMS via Hologram Cloud, but also saw this blog post from a company using the same module (albeit, a different cellular platform). They detailed similar issues and ended up going with a private APN.

I would like to avoid setting up a private APN if possible. Is Hologram Cloud Messaging a viable option here, or is setting up a private APN the best route?

I am not concerned with the added security or flexibility of a private APN, I am truly just looking for the most power efficient way to send information to a device as it cycles without requiring it to initiate a further connection than its eDRX paging windows.

Thank you for any advice/input.