Does a router tells a device to close a TCP connection?

  • #1
431
5
Does a router tells a slave device to close a TCP connection, if the router loses connect from the master device ? So, I have a Qterm-g72 HMI and I am trying to connect it to a Moxa over TCP Modbus. This only works if a Computer or a router is between the Moxa and the HMI. I am trying to found out why. So, my question is does a computer or a router close the connection to the Moxa if it lose it from the HMI ? The HMI is the master so it does the talking and the Moxa is the slave. The Moxa does not know to lost the connection if the HMI does not tell is to close with TCP, so I wanted to know if the Computer or Router would do that ?
Also does anyone else think they might know why the HMI and the Moxa will not work with a router or a computer in between?
 

Answers and Replies

  • #2
402
120
Which Moxa device are you using?
We had some serious issues with the Moxa Nport devices and Modbus.

But no a router doesn't provide any functionality other than routing the packets between device.

When you don't have the router installed does it work at all and then stop? Or just not work period?
Have you tried using a cross over ethernet cable?
 
  • #3
jim mcnamara
Mentor
4,104
2,604
@cpscdave Is correct. routers simply take packets and move them around. What makes your think a router is 'telling' some other network object to close a port? Routers are really dumb - they simply filter stuff, and sometimes drop what they have been instructed to - as bad packets. None of this explicitly requests a 'close operation' on anything that I know of.
 
  • #4
13,830
11,003
Mine allows an automatic internet disconnection depending on idle time and a dayly forced shutdown (with probably an automatic restart.)
 

Related Threads on Does a router tells a device to close a TCP connection?

  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
3
Views
61K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
12
Views
4K
  • Last Post
Replies
9
Views
3K
  • Last Post
Replies
2
Views
3K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
3
Views
3K
Replies
3
Views
12K
Top