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by anonymous

I would like to know if the routers and getways are both capable of handling the most open sockest for data transmission?!

Or by far the routers are technically better to controll and open the sockets for TCP/IP modbus communication.

Thank you

1 Answer

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by anonymous

Thank you for contacting.

It depends on the ISP what ports are allowed and what is not allowed.

Sometimes you need to ask the ISP for opening certain ports.

By default router uses 80,443, 502 and 22 for services like http,https,ssh and modbus .

But that also needs to be allowed by the ISP.

by anonymous
Thank you for your response. Based on this information I have built my network. But unfortunately, it looks there are some issues from the gateway side.

I am using TRB140 to make a Modbus communication between 15 devices. To each gateway I have connected a PLC, and with setting a port forwarding rule I am able to make a connection between master and slaves. In my senstive case I need a fast Modbus/tcp connection, but after some cycle of successful data transfer my connection will be lost. It looks that gateway can not handel fast requests at the same time.
The modbus feature of the gateway has a "keep connection alive" and a "timeout setting",  which I need for my own setting. But I am not using the Modbus feature of the gateway.
Would you plesase assist me to find a solution to keep the connection alive for both master and all 15 slaves ?!
Adding to that, although I have forwarded my external IP with 502 to the local IP (PLC IP) on port 502, still if I use telnet command and my external IP to check the port 502, I see that it is not open?!

I appricate you fast reply to my prolem.


Thank you in advance.