fragmentation
Robert L Ullmann <ariel@world.std.com> Wed, 23 March 1994 02:12 UTC
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Date: Tue, 22 Mar 1994 20:56:58 -0500
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From: Robert L Ullmann <ariel@world.std.com>
Message-Id: <199403230156.AA18775@world.std.com>
To: catnip@world.std.com
Subject: fragmentation
Hi, I won't say who pointed this out, but someone just told me something *very* amusing. RFC791, (everyone has implemented this, right? You know, STD 1 :-) p26 " The Fragment Offset field identifies the fragment location, relative to the beginning of the original unfragmented datagram." Right. Then it goes on to specify a buggy (consider that variable FO is not initialized :-) algorithm for fragmentation and then reassembly. Did anyone read the algorithm? It implies that the fragment offset is relative to TPDU-start ("the data"), which is (as CATNIP says) the way it *ought* to have been done. Has anyone actually done this? Or have you followed the text? Do the existing implementations actually interoperate? Certainly the TPDU-start-relative method is easier to translate ... Best Regards, Robert
- fragmentation Robert L Ullmann