Determinism refers to the ability to calculate and predict application response time (ART), which is the time required for a Quantum Ethernet I/O network system to detect and respond to a single input. When you calculate ART for your application, consider the following:
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Quantum Ethernet I/O architecture features a dedicated module for RIO communications.
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Each remote I/O packet travels from an input module in the remote drop to the controller, then back to an output module in the remote drop.
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Hop count is defined as the number of switches—including switches embedded in RIO devices—that a packet passes through to reach its destination.
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Packet path impacts jitter calculations, because of potential queue delays along its path.
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For remote I/O ART calculations:
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Consider the worst case—i.e., the longest path a packet may need to travel in case of a broken network cable.
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Remote I/O only provides recovery from a single break in the system. This remains true even if a packet is able to arrive at its destination when multiple breaks exist in the system.
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Only count hops and jitter delays along the network path—i.e., from the perspective of the specific remote I/O adapter transmitting the packet. Do not include hops and jitter for other devices in the system that are not on the network path.
