For point-to-point communication, the SNPX protocol is 5 to 10 percent faster than SNP protocol if the average packet size is greater than 100 bytes. The difference becomes smaller when the average packet size get bigger.
The SNPX protocol is 5 or even 10 times faster than the SNP protocol in multi-drop communications.
In multi-drop communications, the SNPX protocol supports broadcast-attach which makes the SNPX device communications option attach to all the PLCs at the same time. After attaching to all the PLCs, the SNPX device communications option can send a request to any PLC in the network without re-attaching to it.
Currently, it takes approximately 0.6 second for the SNP communications option to attach to a PLC each time the communications option sends a data request.
About SNP and SNPX Communications.