Linux ARP and IP stack internals question

From: Patrick Klos (pklos_at_osmium.mv.net)
Date: 09/28/05 

Date: Wed, 28 Sep 2005 00:01:22 +0000 (UTC)

I hope I'm not asking the obvious, but from looking through the Linux
kernel source code, I couldn't readily find the answer.

I know some IP stacks will queue an IP packet while it sends out an
ARP request and awaits the response.

I also know that some IP stacks will basically reuse the outgoing IP
packet buffer (skb?) to send out the ARP request, implying that the original
IP packet is tossed (on the premise that an upper level protocol will
resend/retry if the packet is important).

Can anyone confirm which mechanism the Linux IP stack employs? One way
or the other, I need to confirm what happens to an IP packet when the
target IP address is NOT in the ARP cache?

Thanks for looking!

Patrick
================= GPS based time synchronization solutions =================
    Patrick Klos Email: patrick@timegeeks.com
    Klos Technologies, Inc. Web: http://www.timegeeks.com/
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