[Xorp-hackers] Network stack virtualization on FreeBSD 4.9

[Pavlin Radoslavov]

> 
> I hadn't come across this before:
> 
> "Network stack cloning / virtualization extensions to the FreeBSD kernel"
>   http://www.tel.fer.hr/zec/vimage/
> 
> Might provide a useful environment for running multi-router routing
> tests or experiments using multiple instances of unmodified XORP code
> all running on a single host.

I wasn't aware about it either.
I just finished looking into it, and it looks like a very nice piece
of work. The author has two papers+slides about the implementation
which can provide some insights about the design and the
implementation (go to the author's publications page).
In a very brief summary, practically all network-related global
state inside the kernel is isolated in one big structure which
basically represents a single IP stack, and then all network-related
stuff is taken from that structure.

Obviously, there is lots of manual work involved in modifying the
kernel to achieve this, but the final result (from application point
of view) looks very sweet.

Pavlin