Patent ID: 8510402

Claim:
A first programmable logic controller, comprising: a first central processing unit configured to: determine a first operational status of the first programmable logic controller; communicate with a second programmable logic controller for obtaining a second operational status of the second programmable logic controller; if the first operational status is a primary state, then set an address indication to a first address; if the first operational status is a standby state, then set the address indication to a second address; if the first operational status is an offline state, then determine a calculated mode of operation of the first programmable logic controller from the first operational status and the second operational status, and set the address indication based on the calculated mode of operation; and determine a selection indication; and a first network adapter configured to: receive, from the central processing unit, the address indication, the selection indication, and an indication of the first operational status; if the selection indication is set to a first state, determine an assigned Internet Protocol (IP) address to be the address of the address indication, and if the selection indication is set to a second state, determine the assigned IP address based on the first operational status; and configure the first network adapter with the assigned IP address.