Come on guys.
IP forwarding is not routing. A system becomes a "router" when it starts
IP forwarding but everytime a system sends an IP packet it *routes*, it
decides which of it's interfaces to use to transmit the packet and whether
to forward it to a router or send it directly to it's destination.
Now when a system starts "IP forwarding" it not only makes routing
decisions for itself but will provide that same service for other systems.
So all IP stacks route (they choose between direct sending and using a
default router). Systems that are performing "IP forwarding" are usually
called routers.
To quite Stevens in "TCP/IP Illustrated Vol. 1"
"The routing done by IP, when it searches the routing table and decides
which interface to send a packet out, is a *routing mechanism*. This
differs from a *routing policy* which is a set of rules that decides which
routes go into the routing table." page 112
"Here we purposely call *sun* a router and not a host because when it's
used as a default router, its IP forwarding function is being used, not its
host functionality" page 114
I believe what you two were actually arguing about was (per Stevens
terminology)
1) IP forwarding
2) Routing policy
3) Route broadcasting
(though to be honest I didn't read the entire thread)
At 04:32 PM 2/21/97 -0800, Jerald Josephs wrote:
>Okay, now that we have clarified the argument, I *still* disagree
>with you because I understand that the routing of a packet is the
>intelligent movement of a packet based upon data obtained from a table
>of known routes.
[... stuff deleted...]
>> From: Ryan Russell/SYBASE
>> <Ryan .
Russell @
sybase .
com>
>> Date: 21 Feb 97 16:04:27 EDT
>> My original argument was that IP Forwarding *IS* routing, which you
>> disagreed with.
>>
[ ... More stuff deleted ...]
==============
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