Its going to depend a lot on the class of machine, etc. but there's no
reason it can't work if the boxes on each end, and everything in
between, are up to the task. In days gone by, i.e. before switches
became affordable, it wasn't unusual to put multiple cards in a server
with some dedicated to talking to other key servers and one talking to a
hub with the clients.

Each segment of ethernet acts independently, so in principle, 5 card
pairs and 5 cables should be able to handle 5x the traffic as long as
each box can generate/process 5x the traffic. The trick is to set up the
necessary software to do the load balancing to make things work.

There was a brief period when people where doing this with modems.
They'd have two slip connections on two modems to double their speed.
DSL and cable pretty well took care of that.


--rick


Mike Olson wrote:
> Could someone please settle an argument between my friend, 
> and I?  Is it possible to increase the transfer rate 
> between two computers by putting two network interface 
> cards (NICs) in each computer, and putting two Ethernet 
> connections on each computer, and connecting the two 
> computers with two Ethernet cables?  I said that it would 
> not, and may even slow transfer rates because the 
> processor is switching between two NICs.  Also, since each 
> computer can have only one IP address since each MAC 
> address is unique, and that computer will process the 
> packets of information it receives one at a time.  He 
> thinks that the NICs have buffers in them that allow the 
> packets of information to be stored until the CPU 
> processes them.  So according to him, you can send a chunk 
> of data faster by splitting it in half, sending the halves 
> over two cables, and receive the halves with the other 
> computer and NICs, and put the chunk of data back together 
> again.  He thinks that transfer rates would increase if 
> you increased the CPU speed, since each CPU could split 
> the info and put it back together faster, and faster.  I 
> told him that transfer rates are dependent upon the rate 
> of your NIC and your transfer medium (ex. Ethernet, 
> optical, wireless) and cannot be affected by simply adding 
> more NICs and transfer mediums between two computers.  I 
> think he's confusing processing rates with transfer rates.  
> Whose right? 
>