Eddie Chen writes:
>  I am look at a output from a  tcpdump,  and I found that the  datagram of
> fragmented data  are sent from the "last fragmented"   datagram first.
>  Is this correcrt????
>
>
>
>  (frag 9311:920@8880) (DF)
>  (frag 9311:1480@7400+) (DF)
>  (frag 9311:1480@5920+) (DF)
>  (frag 9311:1480@4440+) (DF)
>  (frag 9311:1480@2960+) (DF)
>  (frag 9311:1480@1480+) (DF)
>  1472 proc-7 (frag 9311:1480@0+)

Yes, it's a useful performance optimisation. It means the recipient
can allocate a network buffer just the right size for the whole
datagram as soon as it receives the first fragment. That saves it
having to reallocate larger and larger buffers for each fragment
that comes in. IIRC, it used to confuse one or two grotty old
embedded TCP/IP stacks but that was years ago and I'd hope that
everything today can handle it.

--Malcolm

--
Malcolm Beattie <[EMAIL PROTECTED]>
Linux Technical Consultant
IBM EMEA Enterprise Server Group...
...from home, speaking only for myself

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