[Ns-developers] emulation use cases

[Tom Henderson]

Gustavo Carneiro wrote:
> 
> 
> 2009/1/15 Tom Henderson <tomh at tomh.org <mailto:tomh at tomh.org>>
> 
>     Craig is working on Tap device support for emulation, and some
>     questions have arisen about use cases and requirements to support,
>     so I thought I'd raise the issue on the list for any input people
>     might have.
> 
>     Presently, we have an emulation mode documented here:
>     http://www.nsnam.org/docs/manual.html#SEC59
>     it runs the simulator in real-time and allows nodes in a simulation
>     to emit packets that are bridged onto a physical device on the host
>     machine.  ns-3 packets are therefore emitted onto real links.  The
>     ns-3 device must be hand-configured with mac address and does not
>     presently support DHCP configuration of the address.
> 
> 
> One use case I had in mind would be running routing protocols 
> implemented in NS-3 over a real host with real interfaces.  I would 
> expect the "packet socket" that powers EmuNetDevice to be used not only 
> for "emitting" packets but also for receiving packets.  Why is receiving 
> packets on EmuNetDevice not supported?

Sorry for possibly giving the impression above that receiving packets is 
not supported.  Both receiving and transmitting is supported already, 
and would be in the proposed tap device; otherwise it would not be too 
useful.  Section 6.3 in the above cited documentation explains how it is 
presently done.

Tom