Re: [lwip-users] help! Can I use lwIP in this way?

[Kieran Mansley]

On Wed, 2006-09-13 at 09:14 +0800, Wang Zheng wrote:
> ---------
> |     Tx|<-------------------------------------------
> |       |         ---------          ---------       | 
> |TCP/IP |         | Lwip1 |          | Lwip2 |       | 
> |       |         |       |          |       |       |
> |     Rx|-------->|Rx   Tx|--------->|Rx   Tx|------->
> ---------         ---------          ---------    
>    PC           device1        device2
> 
> Please look the graph above:
> There are three devices ,including PC,device1 and device2.
> The lwip have been ported into the device1 and device2.
> Tx: the pin to transmit the data to the network
> Rx: the pin to receive the data from network

I'm not quite sure what you're trying to achieve here.  The PC seems to
be sending data on its RX port and receiving on its TX - is that a
typo?  

lwIP is just a network stack: it doesn't care how you connect devices
together, as long as everything is configured with a sane IP address,
netmask etc it should work fine.  lwIP is not a router in itself, and
I'm not sure if it has been heavily tested in situations where there is
more than one physical interface (as you have in the above diagram).
However, there's no reason why it shouldn't work in such a situation, it
just might mean fixing a couple of things if no one else has already.
There would be nothing stopping you incorporating it into a router if
that's what you need, but that functionality isn't part of the core
lwIP.

Hope that helps.

Kieran