SignalR. at least to me is an absolutely underrated technology, when it comes to real-time messaging.
Disclaimer for my embedded readers: yes, at least, if you do not require millisecond response times – but that is seldom the case in standard applications.
Private endpoints for SignalR give developers the possibility to send messages, out of a completely separated Azure VNet, through Azure SignalR (PaaS). These can be notifications, positions, informations or alarms, just as required.
What I really appreciate with this service is is the pub/sub messaging approach, which scales great and reduces dependencies between client and publisher to a minimum.
All coming as PaaS in a serverless fashion! This is definitely worth a look!