Mapping to the ISA-95 Model
ANSI/ISA-95
provides a common view of industrial IT systems, which can be
helpful for understanding the role of edge gateways and hybrid cloud
IIoT environments. Because of the latency and availability
characteristics of the WAN, it is not recommended to take a
dependency on remote resources for Level 0-1 systems. Critical Level
2 systems should also be local, but additional remote monitoring may
be layered on so that operations staff can observe global trends. It
is recommended that data delays and gaps for these remote Level 2
systems can cause only observability failures and not production
impact.
Level 3 and Level 4 systems can benefit from the properties of
remote computing, including the ability to aggregate data from
multiple sites and the ability to perform compute-intensive
analytics tasks.
Edge gateways are generally found in layer 3 and OI/IT Gateways
responsible for industrial protocol conversion are often found in
layer 2 of the Purdue model.
