Whether POX can communicate with your hosts is mostly a function of your 
network setup.  In lots of cases, the network that POX communicates to switches 
on and the network that the switches control are entirely separate and never 
actually meet (often these are called the control network and the data network 
respectivelt).  In this case, having POX and a host communicate directly isn't 
possible.  Indirectly, though, there's at least one kind of hacky possibility.  
Sam Russell did an example of it -- tunneling between the data network and a 
tap interface on the controller machine over the OpenFlow connection via 
packet-in and packet-out.  (You could also potentially use pcap via pxpcap 
instead of a tap.)  There are issues with this approach, but it may suit some 
need.  You can read his blog post about it here:
http://pieknywidok.blogspot.com/2012/09/tunneling-traffic-through-your-openflow.html

A more straightforward approach is to actually have the controller machine 
exist on the data network.  This is always the case when doing "in-band 
control".  If your switches are, for example, Open vSwitch, the most 
straightforward way is using the "local" interface of the OVS instance.  This 
interface is usually down by default, but you can up it.  This connects the 
switch machine's local networking stack (which can obviously reach the 
controller because this is how the switch reaches the controller!) to the data 
network.  Obviously, you'll need to install appropriate table entries to allow 
communication between the controller machine (via the local port) and the host 
(via whatever port it's connected to).

Hope that helps.

-- Murphy

On Apr 20, 2014, at 8:19 PM, Chanthan Hel <hel.chantha...@gmail.com> wrote:

> Dear all,
> As usual, POX can connect and keep communication with of switch.
> In case I want to to connect pox to host by using python socket. Is it 
> possible??
> Moreover, in between POX and host  there is one ovs, it still be possible to 
> connect??
> Chanthan
> 
> 
> -- 
> Mr. Chanthan Hel
> Electrical engineering, Faculty of Engineering,
> Chulalongkorn University (CU)
> 
> *Phone: +66 81 456 84 27*
> 

Reply via email to