Re: Multicast encapsulation

[Ahmed A-G Helmy <ahelmy@catarina.usc.edu>]

> Hi,
> 
> My objective is to simulate IP encapsulation.
> 
> I have incoming data packet(Unicast) coming to my node (Foreign Agent)
> which I want
> these packet's IP addr to be changed to a multicast address before leaving
> this node (Foreign Agent) .
> 
> I changed the destination ip address to :
> 
>  (hdrip->dst_ = A multicast address) in the classifier of the Foreign Agent.
> 
> but it didn't work because when the unicast packet comes into my node it
> goes to the classifier for unicast,
> therefore when I changed the address and sent it out the unicast classifier
> couldnot find a slot to send out the packet.

you should not send out the packet through the unicast classifier. 
Instead you should send it to the node entry (i.e. the switch classifier 
that classifies the packet as either unicast or multicast).

> 
> Maybe in the first place  I am able to direct the unicast packet into the
> multicast classifier at my node, it will work.

yes,.. it should, if you have the multicast tree setup properly. If you 
send the packet to the node entry, it will be automatically sent to the 
multicast classifier if its dst is a multicast address. 
Note, however, that the src address also matters (since routing a 
multicast packet is based on S,G (i.e. the src and dst).

hope this helps,

Regs,
-A

> 
> Does anyone know how to do that?
> or there is a better way to simulate IP encapsulation.
> 
> 
> Thanks.
> 
> 
> Ching Wi
> 
> 
>