net.inet.ip.forwarding and net.inet.ip.fastforwarding

[gnn at freebsd.org]

At Thu, 8 Sep 2005 22:11:15 +0000,
Marcin Jessa wrote:
> 
> Hi guys.
> 
> What's the difference between net.inet.ip.forwarding and
> net.inet.ip.fastforwarding ?
> What's the role of net.inet.ip.fastforwarding ?
> 

net.inet.ip.fastforwarding tells the network code to send packets
through a different code path through the kernel, one which can
forward packets more quickly than the default code path. The fast
forwarding path does minimal checks on packets that are not destined
for the computer acting as a router before forwarding the packet.  The
necessary checks are made, but no more than those that are necessary,
this speeds up packet processing when packets are being routed between
interface.

net.inet.ip.forwarding controls whether or not the computer acting as
a router will forward packets at all.  The default value is false,
which means that packets are NOT forwarded.  This variable must be set
explicitly by the user or administrator for FreeBSD to act as a
router.

I hope this helps,
George