Document net.inet.ip.fastforwarding, and the fact that it bypasses the

ipfirewall code.

Submitted by:	Ruslan Ermilov <ru@ucb.crimea.ua>

share/man/man4/inet.4

@@ -30,7 +30,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     From: @(#)inet.4	8.1 (Berkeley) 6/5/93
-.\"	$Id$
+.\"	$Id: inet.4,v 1.8 1997/02/22 13:24:32 peter Exp $
 .\"
 .Dd February 14, 1995
 .Dt INET 4
@@ -209,19 +209,28 @@ A number of variables are implemented in the net.inet branch of the
 MIB.  In addition to the variables supported by the transport
 protocols (for which see the respective manual pages), the following
 general variables are defined:
-.Bl -tag -width IPCTL_SENDREDIRECTS
+.Bl -tag -width IPCTL_FASTFORWARDING
 .It Dv IPCTL_FORWARDING
 .Pq ip.forwarding
-Boolean: enable/disable forwarding of IP packets (default depends on
-the 
-.Dv GATEWAY
-kernel configuration option).
+Boolean: enable/disable forwarding of IP packets.
+Defaults to off.
+.It Dv IPCTL_FASTFORWARDING
+.Pq ip.fastforwarding
+Boolean: enable/disable the use of fast IP forwarding code.
+Defaults to off.
+When fast forwarding is enabled, IP packets are forwarded directly to
+the appropriate network interface with a minimal validity checking, which
+greatly improves the throughput.  On the other hand, they bypass the
+standard procedures, such as IP option processing and
+.Xr ipfirewall 4
+checking.
+It is not guaranteed that every packet will be fast-forwarded.
 .It Dv IPCTL_SENDREDIRECTS
 .Pq ip.redirect
 Boolean: enable/disable sending of ICMP redirects in response to
 unforwardable
 .Tn IP
-packets (default true).
+packets. Defaults to on.
 .It Dv IPCTL_DEFTTL
 .Pq ip.ttl
 Integer: default time-to-live
@@ -256,6 +265,7 @@ which initiates dynamic adaptation (default 128).
 .Xr igmp 4 ,
 .Xr intro 4 ,
 .Xr ip 4 ,
+.Xr ipfirewall 4 ,
 .Xr tcp 4 ,
 .Xr ttcp 4 ,
 .Xr udp 4