[Click] Re: click router again

[Eddie Kohler]

Hi Dan,

> in flake-iprouter.click, for example, an usual packet enters into click router from
> eth0, passing "Paint(1)", now color =1.  then goes to lookupIProuter(). I suppose  after
> checking lookup router, the packet should go to eth1, thus the packet has to pass
> "CheckPaint(2)". in CheckPaint(2). if color=2 then packet goes on, if not , packet will
> be droped and ICMP message packet will produce to redirect back to the lookup. Is it
> that way?

No, you've got it backwards. If color != 2 the packet goes on, if color=2,
the packet will be copied and one copy will create a redirect. (BTW the
element is now called PaintTee.)

> if the packet is usual, not the packet for error message, why it should be droped or
> redirect? just for the color is different?
				  *********(should read "the same")

Because that is what the standards require. It is weird for the router to
receive a packet on some interface, then forward the packet out to the
_very same interface_. It could easily be a routing loop.

Eddie