NiagaraAX single-site network application
In this example, a customer has a single site with a LAN, connecting to the Internet through a firewall (refer to Figure 5). The firewall provides security, as well as network address translation (NAT), which provides company devices with public IP addresses so that they are accessible from the Internet.
The site has multiple JACE controllers controlling field devices. These JACEs have private IP addresses so they are not accessible by the browser user interface (BUI) user located across the Internet. However, they are available to the BUI user located on the same LAN.
The AXSupervisor has a public IP address assigned to it in the firewall. It can be reached by the BUI user located across the Internet (the external user) and also the internal BUI user. In this example, the AXSupervisor has been engineered to include Px pages that show real-time information originating from the JACEs. To accomplish this, The AXSupervisor proxies data in the different JACE stations. In addition, the AXSupervisor functions as a supervisory station, archiving the other stations’ data logs, alarms, and so on. This data is available to either BUI user.
The network site administrator chooses to place the AXSupervisor outside the enterprise LAN but just behind the firewall. This allows faster access by the external BUI user because the network traffic between the external host and the AXSupervisor does not come onto the customer’s enterprise LAN (which may be congested).
Figure 5 Typical single-site (LAN) architecture
