OptoMMP vs HTTP data transfer size


I know there are various ways to communicate between 2 online EPIC devices.
So comparing between OptoMMP (PAC Control) and HTTP Rest API (Node-RED).
Which one is more reliable?

Best Regards,

There is a significant difference between those two methods.
Peer-to-peer from PAC Control using MMP scratch pad will be very fast and efficient since there are a lot of commands build into PAC Control for those MMP areas and many table or range type commands.
It does require one to be in the PAC Control application at a Windows PC to make any changes.

Node-RED is web browser based so that makes it slightly more flexible.
But, the REST API is https TCP/user/pass, so its pretty heavy. Each and every transaction has to be encrypted and decrypted and ACK/NAK’ed

If the two EPIC devices are on the same network, or VLAN/VPN, then perhaps MMP would be your answer.
If the two EPIC devices are on a WAN with unknown network traffic, then REST with its https would be better suited perhaps.

Lastly, the volume and frequency of would be a factor that should be also be considered.

To your question. Both are reliable.