Re: Urgent as Framing Hint?

[Luigi Rizzo <luigi@info.iet.unipi.it>]

> Hey, if you "integrate" TCP with iSCSI on both ends, you can use the 
> following kludge to frame segments.
> 
> Use a variant TCP checksum on each datagram that starts a segment.  The 
> variant checksum is created by adding in a suitable constant magic 
> value.  This has a negligible effect on end-to-end error detection, and 
> allows distinguishing buffer boundaries.

not that i don't like the idea, but this way any "standard" receiver
will not understand the new checksum and drop the packet. Net effect
is that you can only talk to systems that understand the new checksum
style unless you have some way to negotiate thhis feature.  If you
don't, i fail to see how this is different from having a totally
different protocol which happens to have the same ID as TCP (perhaps
to get through firewalls ?).

	cheers
	luigi
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 Luigi RIZZO, luigi@iet.unipi.it  . ACIRI/ICSI (on leave from Univ. di Pisa)
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