Re: GSoC: the plan for the project network virtualization

[zhengda]

olafBuddenhagen@gmx.net wrote:
> Hi,
>
> On Sat, May 31, 2008 at 04:17:37PM +0200, Zheng Da wrote:
>
>   
> > step 1. A mechanism for different pfinet servers to communicate with each
> > other:
> > There are two possible solutions to reach the goal at least: the BPF
> > translator and the hypervisor.
For the approach of the BPF translator, the BPF translator controls the 
BPF rules.
The packet from pfinet is sent to the kernel directly. The kernel makes 
the decision to deliver the packet to another pfinet, or send it to the 
network.
the task is (as my understanding):
1) finish the BPF translator
2) separate the network device in Mach into two parts:
   control device where the BPF translator set the BPF rules (which 
need the privilege)
   packet device where the pfinet sends data to (every user can have 
the permission to do it)
3) because any pfinet executed by the user can send packets to the device,
   a mechanism must be used in the kernel to control the packet.
   is the BPF filter enough to filter the unexpected packet.

For the approach of the hypervisor, every packet is sent to the hypervisor.
The hypervisor forwards the packet to some other pfinets or send it to 
the kernel and the kernel sends it to the network.
the task, I think, is:
1) hypervisor creates a virtual network interface
   How is the programming interface like for the virtual network interface?
   I mean, is the pfinet still able to open it with device_open()?
      device_open (master_device, D_WRITE | D_READ, dev->name, 
&edev->ether_port);
   If pfinet can open the interface with device_open(), I think we need 
to write another program like boot to give pfinet the pseudo master 
device port and help pfinet open the virtual network interface.
   The second question is: who can create the virtual network 
interface? Is the privilege needed to do it?
   I still don't understand who should check and control the packet.
2) hypervisor does the routing, and sends the packet to the right pfinet 
server.

Best,
Zheng Da