RTU baud rate


amir mohammadi

what charachter's affect on calculation of baud rate if we use ethernet 100base-t layer2?
is there table or some thing else for calculation?
If you are using 100base-t Ethernet, then the Ethernet baud rate is 100 mega-bits per second. That is a fixed rate. However, if something else on your network is 10base-t, then the Ethernet baud rate has to slow down to 10 mega-bits per second.
You are technically correct according to the IEEE 802.2 Ethernet standard - BUT that only applies to the original collision-domain Ethernet in which many devices share a common line. In modern Ethernet networks, there is only one device per Ethernet port on a switch. The communications between the switch and the device, assuming a switch that is rated at 10/100/1000 megabits per second, is as fast as the device can communicate. Each port of the switch is independent, so including a device capable of only 10 mb/sec does not slow down any other communications. This is one of the reasons why we use switches. The other is that full duplex switches make the network deterministic.

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But maybe your real question is how to calculate the maximum data throughput.

This is a difficult question to answer, because it depends on what other devices are using the same physical network and what kind of hub or switch is used to connect them together.

There's another thread about this: