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|00000000| 46 72 6f 6d 20 6a 73 71 | 20 20 54 75 65 20 41 75 |From jsq|  Tue Au|
|00000010| 67 20 31 34 20 32 31 3a | 31 34 3a 30 39 20 31 39 |g 14 21:|14:09 19|
|00000020| 39 30 0a 52 65 63 65 69 | 76 65 64 3a 20 62 79 20 |90.Recei|ved: by |
|00000030| 75 75 6e 65 74 2e 75 75 | 2e 6e 65 74 20 28 35 2e |uunet.uu|.net (5.|
|00000040| 36 31 2f 31 2e 31 34 29 | 20 0a 09 69 64 20 41 41 |61/1.14)| ..id AA|
|00000050| 31 34 35 39 33 3b 20 54 | 75 65 2c 20 31 34 20 41 |14593; T|ue, 14 A|
|00000060| 75 67 20 39 30 20 32 31 | 3a 31 34 3a 30 39 20 2d |ug 90 21|:14:09 -|
|00000070| 30 34 30 30 0a 46 72 6f | 6d 3a 20 52 61 6e 64 79 |0400.Fro|m: Randy|
|00000080| 20 43 61 6d 70 62 65 6c | 6c 20 3c 72 61 6e 64 79 | Campbel|l <randy|
|00000090| 63 40 68 70 66 63 6c 6a | 2e 68 70 2e 63 6f 6d 3e |c@hpfclj|.hp.com>|
|000000a0| 0a 4e 65 77 73 67 72 6f | 75 70 73 3a 20 63 6f 6d |.Newsgro|ups: com|
|000000b0| 70 2e 73 74 64 2e 75 6e | 69 78 0a 53 75 62 6a 65 |p.std.un|ix.Subje|
|000000c0| 63 74 3a 20 52 65 3a 20 | 6e 65 65 64 20 50 4f 53 |ct: Re: |need POS|
|000000d0| 49 58 20 63 6b 73 75 6d | 20 74 61 62 6c 65 73 0a |IX cksum| tables.|
|000000e0| 4d 65 73 73 61 67 65 2d | 49 64 3a 20 3c 31 31 31 |Message-|Id: <111|
|000000f0| 38 39 40 63 73 2e 75 74 | 65 78 61 73 2e 65 64 75 |89@cs.ut|exas.edu|
|00000100| 3e 0a 53 65 6e 64 65 72 | 3a 20 66 6c 65 74 63 68 |>.Sender|: fletch|
|00000110| 65 72 40 63 73 2e 75 74 | 65 78 61 73 2e 65 64 75 |er@cs.ut|exas.edu|
|00000120| 0a 52 65 70 6c 79 2d 54 | 6f 3a 20 73 74 64 2d 75 |.Reply-T|o: std-u|
|00000130| 6e 69 78 40 75 75 6e 65 | 74 2e 75 75 2e 6e 65 74 |nix@uune|t.uu.net|
|00000140| 0a 44 61 74 65 3a 20 31 | 34 20 41 75 67 20 39 30 |.Date: 1|4 Aug 90|
|00000150| 20 32 33 3a 31 38 3a 30 | 34 20 47 4d 54 0a 41 70 | 23:18:0|4 GMT.Ap|
|00000160| 70 61 72 65 6e 74 6c 79 | 2d 54 6f 3a 20 73 74 64 |parently|-To: std|
|00000170| 2d 75 6e 69 78 2d 61 72 | 63 68 69 76 65 0a 0a 46 |-unix-ar|chive..F|
|00000180| 72 6f 6d 3a 20 20 52 61 | 6e 64 79 20 43 61 6d 70 |rom:  Ra|ndy Camp|
|00000190| 62 65 6c 6c 20 3c 72 61 | 6e 64 79 63 40 68 70 66 |bell <ra|ndyc@hpf|
|000001a0| 63 6c 6a 2e 68 70 2e 63 | 6f 6d 3e 0a 0a 3e 46 72 |clj.hp.c|om>..>Fr|
|000001b0| 6f 6d 3a 20 20 61 6e 64 | 72 65 77 40 61 6c 69 63 |om:  and|rew@alic|
|000001c0| 65 2e 75 75 63 70 20 28 | 41 6e 64 72 65 77 20 48 |e.uucp (|Andrew H|
|000001d0| 75 6d 65 29 0a 3e 0a 3e | 09 69 20 77 6f 75 6c 64 |ume).>.>|.i would|
|000001e0| 20 68 61 74 65 20 74 6f | 20 63 61 75 73 65 20 74 | hate to| cause t|
|000001f0| 72 6f 75 62 6c 65 20 62 | 75 74 20 63 61 6e 20 61 |rouble b|ut can a|
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|00000210| 68 79 20 63 6b 73 75 6d | 20 75 73 65 73 20 61 6e |hy cksum| uses an|
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|00000230| 6e 20 43 52 43 2d 33 32 | 20 66 6f 72 20 69 74 73 |n CRC-32| for its|
|00000240| 20 70 6f 6c 79 6e 6f 6d | 69 61 6c 3f 0a 3e 28 69 | polynom|ial?.>(i|
|00000250| 20 61 6d 20 6e 6f 74 20 | 31 30 30 30 25 20 73 75 | am not |1000% su|
|00000260| 72 65 20 69 74 20 69 73 | 6e 27 74 20 62 75 74 20 |re it is|n't but |
|00000270| 61 6d 20 66 61 69 72 6c | 79 20 73 75 72 65 2e 29 |am fairl|y sure.)|
|00000280| 0a 3e 69 74 20 72 65 61 | 6c 6c 79 20 66 72 6f 73 |.>it rea|lly fros|
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|00000310| 6f 73 69 78 20 70 69 63 | 6b 73 20 73 6f 6d 65 20 |osix pic|ks some |
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|00000340| 72 65 63 6f 6d 6d 65 6e | 64 61 74 69 6f 6e 0a 3e |recommen|dation.>|
|00000350| 69 73 20 74 68 61 74 20 | 70 61 74 68 61 6c 69 61 |is that |pathalia|
|00000360| 73 20 75 73 65 73 20 69 | 74 20 28 6e 6f 74 20 73 |s uses i|t (not s|
|00000370| 74 72 69 63 74 6c 79 20 | 74 68 65 20 68 69 67 68 |trictly |the high|
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|000003a0| 2d 4e 75 6d 62 65 72 3a | 20 56 6f 6c 75 6d 65 20 |-Number:| Volume |
|000003b0| 32 31 2c 20 4e 75 6d 62 | 65 72 20 32 33 0a 3e 2d |21, Numb|er 23.>-|
|000003c0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 0a 0a 57 65 6c 6c 2c |--------|-..Well,|
|000003d0| 20 49 20 68 61 64 20 73 | 6f 6d 65 20 70 61 72 74 | I had s|ome part|
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|00000420| 65 72 74 61 69 6e 6c 79 | 20 6e 6f 20 69 6e 74 65 |ertainly| no inte|
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|00000480| 6a 65 61 6e 73 3f 29 2e | 20 20 0a 0a 54 68 65 20 |jeans?).|  ..The |
|00000490| 44 72 61 66 74 20 39 20 | 73 70 65 63 20 66 6f 72 |Draft 9 |spec for|
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|000004b0| 74 68 61 74 20 77 61 73 | 20 64 65 72 69 76 65 64 |that was| derived|
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|000004d0| 0a 68 61 64 20 61 20 70 | 72 6f 62 6c 65 6d 20 69 |.had a p|roblem i|
|000004e0| 6e 20 74 68 61 74 20 69 | 74 20 77 6f 75 6c 64 20 |n that i|t would |
|000004f0| 74 6f 6f 20 6f 66 74 65 | 6e 20 79 69 65 6c 64 20 |too ofte|n yield |
|00000500| 69 64 65 6e 74 69 63 61 | 6c 20 72 65 73 75 6c 74 |identica|l result|
|00000510| 73 20 66 6f 72 0a 66 69 | 6c 65 73 20 74 68 61 74 |s for.fi|les that|
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|00000600| 69 6e 67 20 73 74 61 6e | 64 61 72 64 20 28 49 53 |ing stan|dard (IS|
|00000610| 4f 20 38 38 30 32 2d 33 | 29 2c 20 73 6f 20 77 65 |O 8802-3|), so we|
|00000620| 20 0a 74 68 6f 75 67 68 | 74 20 69 74 20 77 6f 75 | .though|t it wou|
|00000630| 6c 64 20 62 65 20 61 70 | 70 72 6f 70 72 69 61 74 |ld be ap|propriat|
|00000640| 65 20 74 6f 20 75 73 65 | 2e 20 20 49 6e 20 66 61 |e to use|.  In fa|
|00000650| 63 74 2c 20 66 69 6e 64 | 69 6e 67 20 61 20 6b 6e |ct, find|ing a kn|
|00000660| 6f 77 6e 2c 0a 73 74 61 | 6e 64 61 72 64 20 70 6f |own,.sta|ndard po|
|00000670| 6c 79 6e 6f 6d 69 61 6c | 20 74 6f 20 75 73 65 20 |lynomial| to use |
|00000680| 77 61 73 20 6f 6e 65 20 | 6f 66 20 6f 75 72 20 63 |was one |of our c|
|00000690| 72 69 74 65 72 69 61 2e | 20 20 41 6e 64 20 69 74 |riteria.|  And it|
|000006a0| 20 67 61 76 65 20 67 6f | 6f 64 20 0a 65 6d 70 69 | gave go|od .empi|
|000006b0| 72 69 63 61 6c 20 72 65 | 73 75 6c 74 73 20 6f 6e |rical re|sults on|
|000006c0| 20 73 6f 6d 65 20 66 69 | 6c 65 73 65 74 73 20 74 | some fi|lesets t|
|000006d0| 68 61 74 20 68 61 64 20 | 65 78 70 6f 73 65 64 20 |hat had |exposed |
|000006e0| 77 65 61 6b 6e 65 73 73 | 65 73 20 69 6e 20 6f 74 |weakness|es in ot|
|000006f0| 68 65 72 20 0a 69 6d 70 | 6c 65 6d 65 6e 74 61 74 |her .imp|lementat|
|00000700| 69 6f 6e 73 2e 0a 0a 0a | 09 52 61 6e 64 79 20 43 |ions....|.Randy C|
|00000710| 61 6d 70 62 65 6c 6c 0a | 0a 0a 0a 56 6f 6c 75 6d |ampbell.|...Volum|
|00000720| 65 2d 4e 75 6d 62 65 72 | 3a 20 56 6f 6c 75 6d 65 |e-Number|: Volume|
|00000730| 20 32 31 2c 20 4e 75 6d | 62 65 72 20 33 31 0a 0a | 21, Num|ber 31..|
+--------+-------------------------+-------------------------+--------+--------+