# statfull communication over 2 interfaces



## sai (Jan 19, 2009)

Hi,

Is that possible to establish a same communication over 2 differents interfaces?

I mean is that possible to ping a distant machine by sending ICMP requests on ethernet card and recived ICMP answers on wireless interface, for instance?

I know this senario is tricky but I think this kind of situation could occur if there is a firewall between the client and the server, for example.

So do you think FreeBSD is able to allow any statfull communication when we use a specific interfaces on input and on output?

Thanks for all ideas,

Sai


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## SirDice (Jan 19, 2009)

sai said:
			
		

> I mean is that possible to ping a distant machine by sending ICMP requests on ethernet card and recived ICMP answers on wireless interface, for instance?


If this happens you have serious routing issues.


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## sai (Jan 19, 2009)

SirDice said:
			
		

> If this happens you have serious routing issues.



Yes I think so too. But I would like simply to know if it's possible.


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## SirDice (Jan 19, 2009)

Not sure.. but it shouldn't matter. The tcp/ip stack strips off the ip addresses so higher layers don't actually look at it. As long as the sequence numbers are correct it shouldn't matter (Think tcp/ip hijack).

But there's a high probability any firewall running on that machine will flag and deny it.


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## sai (Jan 20, 2009)

Thank you SirDice for helping.

Regards


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