[ntp:hackers] Findinterface

Heiko Gerstung heiko.gerstung at meinberg.de
Mon Jun 13 00:55:00 PDT 2005


Hi Brad,

Brad Knowles schrieb:

> At 8:10 AM +0200 2005-06-10, Heiko Gerstung wrote:
>
>>  Sorry that I miss the point, but if auth is related to the IP 
>> address, why
>>  do we need to find the physical interface for an association? The IP
>>  address of the sender and the receiver should be available in every 
>> packet
>>  we receive, no matter over which interface we receive it, right?
>
>
>     My understanding is that this is not true by the time the IP stack 
> has done it's job of unwrapping the package.  You'll have the source 
> IP but not the target IP, so you won't know the interface, which means 
> that you can't guarantee that the response will go out the same 
> interface and from the same target (now source) IP.

To me it feels like we are dealing with something we shouldn't need to 
take care of. Why do we need to bother which interface is used to send a 
package to someone? Isn't that something the "routing functions" in our 
"kernel" are responsible for?

>     You have to back-track to figure how to fill in the missing bits.

If you really need them, but I doubt that. I'd like to learn why I'm 
wrong and I kindly ask all of you to educate me :-)

Thanks for your patience,
kind regards,
Heiko

-- 
------------------------------------------------------------------------

*MEINBERG Funkuhren*
Auf der Landwehr 22
D-31812 Bad Pyrmont, Germany
Tel.: ++49 (0)5281 9309-25
Fax: ++49 (0)5281 9309-30
eMail: heiko.gerstung at meinberg.de <mailto:heiko.gerstung at meinberg.de>
Internet: www.meinberg.de <http://www.meinberg.de/>

------------------------------------------------------------------------

Meinberg radio clocks: 25 years of accurate time worldwide




More information about the hackers mailing list