Software Vault: The Collection for Macintosh

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MacBinary | 1993-01-05 | 8.3 KB | [TEXT/ttxt]
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MacOS 8.1 extracted |
Win98 extracted |
DOS extracted
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This file was processed as: MacBinary (archive/macBinary).
Confidence	Program	Detection	Match Type	Support
`1%`	dexvert	MacBinary `(archive/macBinary)`	fallback	Supported
`1%`	dexvert	Text File `(text/txt)`	fallback	Supported
`100%`	file	MacBinary II, inited, Tue Jan 5 07:48:47 1993, modified Tue Jan 5 07:48:47 1993, creator SimpleText, type ASCII, 7839 bytes "SLFP Info" , at 0x1f1f 286 bytes resource	default (weak)
`99%`	file	data	default
`74%`	TrID	Macintosh plain text (MacBinary)	default
`25%`	TrID	MacBinary 2	default (weak)
`100%`	dearkID	deark: macbinary	default
`100%`	siegfried	fmt/1762 MacBinary (II)	default
`100%`	lsar	MacBinary	default
id metadata
key	value
macFileType	`[TEXT]`
macFileCreator	`[ttxt]`
hex view
+--------+-------------------------+-------------------------+--------+--------+
|00000000| 00 09 53 4c 46 50 20 49 | 6e 66 6f 00 00 00 00 00 |..SLFP I|nfo.....|
|00000010| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000020| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000030| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000040| 00 54 45 58 54 74 74 78 | 74 01 00 00 00 00 00 00 |.TEXTttx|t.......|
|00000050| 00 00 00 00 00 1e 9f 00 | 00 01 1e a7 6f 34 2f a7 |........|....o4/.|
|00000060| 6f 34 2f 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |o4/.....|........|
|00000070| 00 00 00 00 00 00 00 00 | 00 00 81 81 99 ea 00 00 |........|........|
|00000080| 46 72 6f 6d 3a 20 44 65 | 77 61 79 6e 65 20 48 65 |From: De|wayne He|
|00000090| 6e 64 72 69 63 6b 73 20 | 57 41 38 44 5a 50 0d 54 |ndricks |WA8DZP.T|
|000000a0| 6f 3a 20 20 20 55 73 65 | 72 73 20 6f 66 20 4e 45 |o:   Use|rs of NE|
|000000b0| 54 2f 4d 61 63 20 32 2e | 33 2e 31 35 20 28 61 6e |T/Mac 2.|3.15 (an|
|000000c0| 64 20 68 69 67 68 65 72 | 20 76 65 72 73 69 6f 6e |d higher| version|
|000000d0| 73 29 0d 0d 48 65 72 65 | 20 69 73 20 74 68 65 20 |s)..Here| is the |
|000000e0| 64 6f 63 75 6d 65 6e 74 | 61 74 69 6f 6e 20 6f 6e |document|ation on|
|000000f0| 20 53 4c 46 50 2e 0d 0d | 49 20 74 65 73 74 65 64 | SLFP...|I tested|
|00000100| 20 53 4c 46 50 20 77 69 | 74 68 20 74 68 65 20 66 | SLFP wi|th the f|
|00000110| 6f 6c 6c 6f 77 69 6e 67 | 20 61 74 74 61 63 68 20 |ollowing| attach |
|00000120| 63 6f 6d 6d 61 6e 64 3a | 0d 0d 23 20 53 65 74 75 |command:|..# Setu|
|00000130| 70 20 74 68 65 20 53 4c | 46 50 20 53 75 70 70 6f |p the SL|FP Suppo|
|00000140| 72 74 0d 61 74 74 61 63 | 68 20 61 73 79 20 32 20 |rt.attac|h asy 2 |
|00000150| 61 20 73 6c 66 70 20 73 | 66 30 20 38 30 39 32 20 |a slfp s|f0 8092 |
|00000160| 31 31 35 32 20 32 34 30 | 30 20 61 74 64 74 31 2c |1152 240|0 atdt1,|
|00000170| 32 33 34 36 2d 36 37 38 | 39 0d 20 0d 0d 3d 3d 3d |2346-678|9. ..===|
|00000180| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00000190| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000001a0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000001b0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 0d |========|=======.|
|000001c0| 0d 20 0d 20 0d 20 0d 20 | 20 20 20 20 4d 4e 45 54 |. . . . |    MNET|
|000001d0| 3a 4d 49 54 2e 53 4c 46 | 50 20 20 20 20 20 20 20 |:MIT.SLF|P       |
|000001e0| 20 20 20 20 20 20 20 20 | 4c 61 73 74 20 75 70 64 |        |Last upd|
|000001f0| 61 74 65 64 3a 20 31 30 | 20 4e 6f 76 65 6d 62 65 |ated: 10| Novembe|
|00000200| 72 20 31 39 38 37 0d 20 | 20 20 20 20 0d 20 20 20 |r 1987. |    .   |
|00000210| 20 20 54 68 69 73 20 66 | 69 6c 65 20 63 6f 6e 74 |  This f|ile cont|
|00000220| 61 69 6e 73 20 74 65 63 | 68 6e 69 63 61 6c 20 64 |ains tec|hnical d|
|00000230| 6f 63 75 6d 65 6e 74 61 | 74 69 6f 6e 20 6f 66 20 |ocumenta|tion of |
|00000240| 74 68 65 20 4d 49 54 20 | 53 65 72 69 61 6c 20 4c |the MIT |Serial L|
|00000250| 69 6e 65 0d 20 20 20 20 | 20 46 72 61 6d 69 6e 67 |ine.    | Framing|
|00000260| 20 50 72 6f 74 6f 63 6f | 6c 2c 20 61 73 20 69 6d | Protoco|l, as im|
|00000270| 70 6c 65 6d 65 6e 74 65 | 64 20 69 6e 20 74 68 65 |plemente|d in the|
|00000280| 20 4d 65 72 69 74 20 43 | 6f 6d 70 75 74 65 72 20 | Merit C|omputer |
|00000290| 4e 65 74 77 6f 72 6b 2e | 0d 20 20 20 20 20 49 74 |Network.|.     It|
|000002a0| 20 77 61 73 20 72 65 74 | 79 70 65 64 20 66 72 6f | was ret|yped fro|
|000002b0| 6d 20 74 68 65 20 6f 72 | 69 67 69 6e 61 6c 20 69 |m the or|iginal i|
|000002c0| 6e 66 6f 72 6d 61 74 69 | 6f 6e 20 66 72 6f 6d 20 |nformati|on from |
|000002d0| 4d 49 54 20 6f 6e 20 31 | 31 2f 31 30 2f 38 37 2e |MIT on 1|1/10/87.|
|000002e0| 0d 20 20 20 20 0d 20 20 | 20 20 20 20 20 20 20 20 |.    .  |        |
|000002f0| 20 20 20 20 20 20 41 70 | 70 65 6e 64 69 78 20 49 |      Ap|pendix I|
|00000300| 3a 20 20 53 65 72 69 61 | 6c 20 6c 69 6e 65 20 46 |:  Seria|l line F|
|00000310| 72 61 6d 69 6e 67 20 50 | 72 6f 74 6f 63 6f 6c 0d |raming P|rotocol.|
|00000320| 20 20 20 20 20 0d 20 20 | 20 20 20 20 20 20 20 20 |     .  |        |
|00000330| 28 54 68 69 73 20 64 65 | 73 63 72 69 70 74 69 6f |(This de|scriptio|
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|00000350| 20 6f 6c 64 20 66 69 6c | 65 20 77 72 69 74 74 65 | old fil|e writte|
|00000360| 6e 20 20 77 68 65 6e 20 | 20 77 65 0d 20 20 20 20 |n  when | we.    |
|00000370| 20 77 65 72 65 20 20 20 | 66 69 72 73 74 20 20 69 | were   |first  i|
|00000380| 6d 70 6c 65 6d 65 6e 74 | 69 6e 67 20 20 74 68 65 |mplement|ing  the|
|00000390| 20 20 70 72 6f 74 6f 63 | 6f 6c 2e 20 20 20 44 65 |  protoc|ol.   De|
|000003a0| 74 61 69 6c 73 20 20 61 | 72 65 20 20 73 74 69 6c |tails  a|re  stil|
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|000003d0| 20 20 20 20 20 20 20 20 | 20 20 54 68 69 73 20 20 |        |  This  |
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|000003f0| 20 64 6f 63 75 6d 65 6e | 74 61 74 69 6f 6e 20 20 | documen|tation  |
|00000400| 6f 6e 20 20 74 68 65 20 | 20 73 65 72 69 61 6c 20 |on  the | serial |
|00000410| 20 6c 69 6e 65 0d 20 20 | 20 20 20 70 72 6f 74 6f | line.  |   proto|
|00000420| 63 6f 6c 20 20 75 73 65 | 64 20 20 62 65 74 77 65 |col  use|d  betwe|
|00000430| 65 6e 20 20 74 68 65 20 | 20 49 42 4d 20 20 50 43 |en  the | IBM  PC|
|00000440| 73 20 20 61 6e 64 20 74 | 68 65 20 50 43 20 47 61 |s  and t|he PC Ga|
|00000450| 74 65 77 61 79 2e 20 20 | 54 68 65 0d 20 20 20 20 |teway.  |The.    |
|00000460| 20 70 72 6f 74 6f 63 6f | 6c 20 68 61 73 20 74 77 | protoco|l has tw|
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|00000480| 77 2d 6c 65 76 65 6c 20 | 70 72 6f 74 6f 63 6f 6c |w-level |protocol|
|00000490| 20 20 28 4c 4c 50 29 20 | 20 61 6e 64 20 20 74 68 |  (LLP) | and  th|
|000004a0| 65 0d 20 20 20 20 20 6c | 6f 63 61 6c 20 20 6e 65 |e.     l|ocal  ne|
|000004b0| 74 20 20 70 72 6f 74 6f | 63 6f 6c 2e 20 20 54 68 |t  proto|col.  Th|
|000004c0| 65 20 6c 6f 77 20 6c 65 | 76 65 6c 20 70 72 6f 74 |e low le|vel prot|
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|000004f0| 69 76 65 72 73 20 69 74 | 20 74 6f 20 74 68 65 20 |ivers it| to the |
|00000500| 50 43 20 47 61 74 65 77 | 61 79 2e 20 20 54 68 65 |PC Gatew|ay.  The|
|00000510| 20 6c 6f 63 61 6c 20 6e | 65 74 20 70 72 6f 74 6f | local n|et proto|
|00000520| 63 6f 6c 20 74 65 6c 6c | 73 20 74 68 65 0d 20 20 |col tell|s the.  |
|00000530| 20 20 20 50 43 20 47 61 | 74 65 77 61 79 20 77 68 |   PC Ga|teway wh|
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|00000550| 74 20 69 74 20 69 73 2e | 20 20 43 75 72 72 65 6e |t it is.|  Curren|
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|00000590| 64 20 41 64 64 72 65 73 | 73 20 52 65 71 75 65 73 |d Addres|s Reques|
|000005a0| 74 2e 20 20 57 68 65 6e | 20 74 68 65 20 20 50 43 |t.  When| the  PC|
|000005b0| 20 20 47 61 74 65 77 61 | 79 0d 20 20 20 20 20 72 |  Gatewa|y.     r|
|000005c0| 65 63 65 69 76 65 73 20 | 20 61 6e 20 20 49 6e 74 |eceives | an  Int|
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|00000600| 20 20 20 20 20 69 6e 74 | 65 72 6e 65 74 20 70 61 |     int|ernet pa|
|00000610| 63 6b 65 74 20 20 74 6f | 20 20 61 20 20 70 72 6f |cket  to|  a  pro|
|00000620| 63 65 73 73 20 20 77 68 | 69 63 68 20 20 63 68 65 |cess  wh|ich  che|
|00000630| 63 6b 73 20 20 74 68 65 | 20 20 70 61 63 6b 65 74 |cks  the|  packet|
|00000640| 20 20 66 6f 72 0d 20 20 | 20 20 20 76 61 6c 69 64 |  for.  |   valid|
|00000650| 69 74 79 20 61 6e 64 20 | 74 68 65 6e 20 73 65 6e |ity and |then sen|
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|00000670| 2e 20 20 4f 6e 20 72 65 | 63 65 69 70 74 20 6f 66 |.  On re|ceipt of|
|00000680| 20 61 6e 20 41 64 64 72 | 65 73 73 0d 20 20 20 20 | an Addr|ess.    |
|00000690| 20 52 65 71 75 65 73 74 | 20 20 70 61 63 6b 65 74 | Request|  packet|
|000006a0| 2c 20 20 74 68 65 20 50 | 43 20 47 61 74 65 77 61 |,  the P|C Gatewa|
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|000006c0| 73 73 20 52 65 71 75 65 | 73 74 20 70 61 63 6b 65 |ss Reque|st packe|
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|00000700| 61 20 20 28 74 68 65 20 | 20 50 43 27 73 20 20 69 |a  (the | PC's  i|
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|00000740| 0d 20 20 20 20 20 0d 20 | 20 20 20 20 20 20 20 20 |.     . |        |
|00000750| 20 4e 65 69 74 68 65 72 | 20 20 74 68 65 20 20 4c | Neither|  the  L|
|00000760| 4c 50 20 20 6e 6f 72 20 | 20 74 68 65 20 20 6c 6f |LP  nor | the  lo|
|00000770| 63 61 6c 20 6e 65 74 20 | 70 72 6f 74 6f 63 6f 6c |cal net |protocol|
|00000780| 20 70 72 6f 76 69 64 65 | 20 66 6f 72 0d 20 20 20 | provide| for.   |
|00000790| 20 20 70 72 69 6f 72 69 | 74 69 7a 65 64 20 74 72 |  priori|tized tr|
|000007a0| 61 6e 73 6d 69 73 73 69 | 6f 6e 73 2c 20 63 68 65 |ansmissi|ons, che|
|000007b0| 63 6b 73 75 6d 73 20 6f | 72 20 20 63 6f 6d 70 6c |cksums o|r  compl|
|000007c0| 65 78 20 20 6c 69 6e 65 | 20 20 63 6f 6e 74 72 6f |ex  line|  contro|
|000007d0| 6c 2e 0d 20 20 20 20 20 | 54 68 65 79 20 20 61 72 |l..     |They  ar|
|000007e0| 65 20 20 6d 65 72 65 6c | 79 20 20 61 20 20 73 69 |e  merel|y  a  si|
|000007f0| 6d 70 6c 65 20 20 77 61 | 79 20 20 74 6f 20 20 67 |mple  wa|y  to  g|
|00000800| 65 74 20 20 70 61 63 6b | 65 74 73 20 20 74 6f 20 |et  pack|ets  to |
|00000810| 61 6e 64 20 66 72 6f 6d | 0d 20 20 20 20 20 6d 61 |and from|.     ma|
|00000820| 63 68 69 6e 65 73 2e 0d | 20 20 20 20 20 0d 20 20 |chines..|     .  |
|00000830| 20 20 20 20 20 20 20 20 | 54 68 65 20 6c 6f 63 61 |        |The loca|
|00000840| 6c 20 6e 65 74 20 70 72 | 6f 74 6f 63 6f 6c 20 63 |l net pr|otocol c|
|00000850| 6f 6e 73 69 73 74 73 20 | 6f 66 20 61 20 66 6f 75 |onsists |of a fou|
|00000860| 72 20 62 79 74 65 20 6c | 65 61 64 65 72 2e 20 20 |r byte l|eader.  |
|00000870| 46 6f 72 0d 20 20 20 20 | 20 61 6e 20 69 6e 74 65 |For.    | an inte|
|00000880| 72 6e 65 74 20 70 61 63 | 6b 65 74 2c 20 74 68 69 |rnet pac|ket, thi|
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|000008e0| 54 68 65 72 65 20 69 73 | 20 6e 6f 20 64 61 74 61 |There is| no data|
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|00000970| 20 70 72 6f 74 6f 63 6f | 6c 2e 0d 20 20 20 20 20 | protoco|l..     |
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|00000a20| 68 65 20 72 65 63 65 69 | 70 74 20 6f 66 20 73 75 |he recei|pt of su|
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|00000a60| 65 74 20 64 69 73 63 61 | 72 64 65 64 2e 0d 20 20 |et disca|rded..  |
|00000a70| 20 20 20 0d 20 20 20 20 | 20 20 20 20 20 20 4c 4c |   .    |      LL|
|00000a80| 50 20 20 63 6f 6e 73 69 | 73 74 73 20 20 6f 66 20 |P  consi|sts  of |
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|00000b00| 20 20 20 20 20 45 4e 44 | 2e 0d 20 20 20 20 20 0d |     END|..     .|
|00000b10| 20 20 20 20 20 20 20 20 | 20 20 41 20 70 61 63 6b |        |  A pack|
|00000b20| 65 74 20 69 73 20 65 6e | 63 6c 6f 73 65 64 20 69 |et is en|closed i|
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|00000b70| 69 74 20 66 69 72 73 74 | 20 73 65 6e 64 73 20 61 |it first| sends a|
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|00000ba0| 20 74 68 65 6e 20 77 61 | 69 74 73 20 61 20 73 75 | then wa|its a su|
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|00000bc0| 20 74 69 6d 65 20 74 6f | 20 72 65 63 65 69 76 65 | time to| receive|
|00000bd0| 20 61 6e 20 41 43 4b 20 | 66 72 6f 6d 20 20 74 68 | an ACK |from  th|
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|00000c30| 75 6d 65 64 20 74 6f 20 | 62 65 20 75 6e 61 62 6c |umed to |be unabl|
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|00000c70| 20 20 20 74 69 6d 65 6f | 75 74 20 69 73 20 73 61 |   timeo|ut is sa|
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|00000cd0| 20 20 0d 20 20 20 20 20 | 20 20 20 20 20 41 66 74 |  .     |     Aft|
|00000ce0| 65 72 20 20 74 68 65 20 | 50 43 20 72 65 63 65 69 |er  the |PC recei|
|00000cf0| 76 65 73 20 74 68 65 20 | 41 43 4b 20 73 69 67 6e |ves the |ACK sign|
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|00000d10| 20 73 65 6e 64 69 6e 67 | 0d 20 20 20 20 20 74 68 | sending|.     th|
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|00000e80| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
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|00001190| 20 20 20 20 54 68 65 20 | 66 69 6e 61 6c 20 63 6f |    The |final co|
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|000012b0| 20 74 68 65 20 73 69 67 | 6e 61 6c 73 20 61 6e 64 | the sig|nals and|
|000012c0| 20 74 68 65 20 45 53 43 | 20 73 65 71 75 65 6e 63 | the ESC| sequenc|
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|00001300| 65 2e 0d 20 20 20 20 20 | 0d 20 20 20 20 20 45 53 |e..     |.     ES|
|00001310| 43 20 20 20 20 20 20 32 | 34 32 20 20 20 20 20 20 |C      2|42      |
|00001320| 20 45 53 43 20 30 0d 20 | 20 20 20 20 52 45 51 20 | ESC 0. |    REQ |
|00001330| 20 20 20 20 20 32 34 33 | 20 20 20 20 20 20 20 45 |     243|       E|
|00001340| 53 43 20 31 0d 20 20 20 | 20 20 41 43 4b 20 20 20 |SC 1.   |  ACK   |
|00001350| 20 20 20 32 34 34 20 20 | 20 20 20 20 20 45 53 43 |   244  |     ESC|
|00001360| 20 32 0d 20 20 20 20 20 | 45 4e 44 20 20 20 20 20 | 2.     |END     |
|00001370| 20 32 34 35 20 20 20 20 | 20 20 20 45 53 43 20 33 | 245    |   ESC 3|
|00001380| 0d 20 20 20 20 20 0d 20 | 20 20 20 20 20 20 20 20 |.     . |        |
|00001390| 20 41 20 20 73 69 6d 70 | 6c 65 20 20 77 61 79 20 | A  simp|le  way |
|000013a0| 74 6f 20 75 6e 73 74 75 | 66 66 20 74 68 65 20 62 |to unstu|ff the b|
|000013b0| 79 74 65 73 20 69 73 20 | 74 6f 20 61 64 64 20 74 |ytes is |to add t|
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|000013d0| 20 20 66 6f 6c 6c 6f 77 | 69 6e 67 20 61 6e 20 45 |  follow|ing an E|
|000013e0| 53 43 20 74 6f 20 74 68 | 65 20 45 53 43 20 74 6f |SC to th|e ESC to|
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|00001410| 75 74 0d 20 20 20 20 20 | 69 74 20 69 6e 20 74 68 |ut.     |it in th|
|00001420| 65 20 70 61 63 6b 65 74 | 20 61 73 20 64 61 74 61 |e packet| as data|
|00001430| 2e 20 20 49 74 20 69 73 | 20 61 6e 20 65 72 72 6f |.  It is| an erro|
|00001440| 72 20 74 6f 20 68 61 76 | 65 20 61 6e 79 20 20 63 |r to hav|e any  c|
|00001450| 68 61 72 61 63 74 65 72 | 0d 20 20 20 20 20 3e 33 |haracter|.     >3|
|00001460| 20 66 6f 6c 6c 6f 77 20 | 61 6e 20 45 53 43 2e 0d | follow |an ESC..|
|00001470| 20 20 20 20 20 0d 20 20 | 20 20 20 20 20 20 20 20 |     .  |        |
|00001480| 49 66 20 20 61 20 6d 61 | 63 68 69 6e 65 20 72 65 |If  a ma|chine re|
|00001490| 63 65 69 76 65 73 20 61 | 6e 79 20 63 68 61 72 61 |ceives a|ny chara|
|000014a0| 63 74 65 72 20 6f 74 68 | 65 72 20 74 68 61 6e 20 |cter oth|er than |
|000014b0| 61 20 52 45 51 20 6f 72 | 20 61 6e 0d 20 20 20 20 |a REQ or| an.    |
|000014c0| 20 41 43 4b 20 77 68 65 | 6e 20 69 74 20 69 73 20 | ACK whe|n it is |
|000014d0| 6e 6f 74 20 69 6e 20 74 | 68 65 20 70 72 6f 63 65 |not in t|he proce|
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|00001500| 74 0d 20 20 20 20 20 73 | 68 6f 75 6c 64 20 64 69 |t.     s|hould di|
|00001510| 73 63 61 72 64 20 74 68 | 61 74 20 63 68 61 72 61 |scard th|at chara|
|00001520| 63 74 65 72 2e 0d 20 20 | 20 20 20 0d 20 20 20 20 |cter..  |   .    |
|00001530| 20 20 20 20 20 20 4c 6f | 77 2d 6c 65 76 65 6c 20 |      Lo|w-level |
|00001540| 20 70 72 6f 74 6f 63 6f | 6c 20 20 73 70 65 63 69 | protoco|l  speci|
|00001550| 66 69 63 61 74 69 6f 6e | 3a 20 49 42 4d 20 74 6f |fication|: IBM to|
|00001560| 20 47 61 74 65 77 61 79 | 2c 20 47 61 74 65 77 61 | Gateway|, Gatewa|
|00001570| 79 0d 20 20 20 20 20 74 | 6f 20 49 42 4d 2e 0d 20 |y.     t|o IBM.. |
|00001580| 20 20 20 20 0d 20 20 20 | 20 20 20 20 20 20 20 54 |    .   |       T|
|00001590| 68 65 20 66 6f 6c 6c 6f | 77 69 6e 67 20 41 53 43 |he follo|wing ASC|
|000015a0| 49 49 20 63 6f 64 65 73 | 20 61 72 65 20 75 73 65 |II codes| are use|
|000015b0| 64 20 61 73 20 66 6c 61 | 67 73 20 69 6e 20 20 74 |d as fla|gs in  t|
|000015c0| 68 65 20 20 6d 61 6e 6e | 65 72 0d 20 20 20 20 20 |he  mann|er.     |
|000015d0| 73 70 65 63 69 66 69 65 | 64 3a 0d 20 20 20 20 20 |specifie|d:.     |
|000015e0| 0d 20 20 20 20 20 32 34 | 32 20 20 20 20 20 20 2d |.     24|2      -|
|000015f0| 20 50 72 65 66 69 78 20 | 20 63 6f 64 65 20 20 66 | Prefix | code  f|
|00001600| 6f 72 20 20 73 65 6e 64 | 69 6e 67 20 20 64 61 74 |or  send|ing  dat|
|00001610| 61 20 20 63 6f 64 65 73 | 20 77 68 69 63 68 20 61 |a  codes| which a|
|00001620| 72 65 20 73 65 74 0d 20 | 20 20 20 20 20 20 20 20 |re set. |        |
|00001630| 20 20 20 20 20 20 20 61 | 73 69 64 65 20 66 6f 72 |       a|side for|
|00001640| 20 70 72 6f 74 6f 63 6f | 6c 20 75 73 65 2e 0d 20 | protoco|l use.. |
|00001650| 20 20 20 20 32 34 33 20 | 20 20 20 20 20 2d 20 52 |    243 |     - R|
|00001660| 65 71 75 65 73 74 20 74 | 6f 20 73 65 6e 64 20 28 |equest t|o send (|
|00001670| 52 45 51 29 2e 0d 20 20 | 20 20 20 32 34 34 20 20 |REQ)..  |   244  |
|00001680| 20 20 20 20 2d 20 41 63 | 6b 6e 6f 77 6c 65 64 67 |    - Ac|knowledg|
|00001690| 65 20 28 41 43 4b 29 2e | 0d 20 20 20 20 20 32 34 |e (ACK).|.     24|
|000016a0| 35 20 20 20 20 20 20 2d | 20 45 6e 64 20 6f 66 20 |5      -| End of |
|000016b0| 70 61 63 6b 65 74 20 28 | 45 4e 44 29 2e 0d 20 20 |packet (|END)..  |
|000016c0| 20 20 20 0d 20 20 20 20 | 20 20 20 20 20 20 41 20 |   .    |      A |
|000016d0| 74 79 70 69 63 61 6c 20 | 64 61 74 61 20 74 72 61 |typical |data tra|
|000016e0| 6e 73 66 65 72 20 6f 63 | 63 75 72 73 20 61 73 20 |nsfer oc|curs as |
|000016f0| 66 6f 6c 6c 6f 77 73 3a | 0d 20 20 20 20 20 0d 20 |follows:|.     . |
|00001700| 20 20 20 20 0d 20 20 20 | 20 20 49 42 4d 20 77 61 |    .   |  IBM wa|
|00001710| 6e 74 73 20 74 6f 20 73 | 65 6e 64 20 70 61 63 6b |nts to s|end pack|
|00001720| 65 74 20 74 6f 20 47 61 | 74 65 77 61 79 3a 20 20 |et to Ga|teway:  |
|00001730| 49 74 20 73 65 6e 64 73 | 20 52 45 51 20 61 6e 64 |It sends| REQ and|
|00001740| 20 77 61 69 74 73 20 66 | 6f 72 20 41 43 4b 2e 0d | waits f|or ACK..|
|00001750| 20 20 20 20 20 47 61 74 | 65 77 61 79 20 69 73 20 |     Gat|eway is |
|00001760| 72 65 61 64 79 20 74 6f | 20 72 65 63 65 69 76 65 |ready to| receive|
|00001770| 20 70 61 63 6b 65 74 3a | 20 20 20 49 74 20 73 65 | packet:|   It se|
|00001780| 6e 64 73 20 41 43 4b 0d | 20 20 20 20 20 49 42 4d |nds ACK.|     IBM|
|00001790| 20 73 65 6e 64 73 20 70 | 61 63 6b 65 74 20 74 6f | sends p|acket to|
|000017a0| 20 47 61 74 65 77 61 79 | 20 66 6f 6c 6c 6f 77 65 | Gateway| followe|
|000017b0| 64 20 62 79 20 45 4e 44 | 2e 0d 20 20 20 20 20 54 |d by END|..     T|
|000017c0| 68 65 20 70 61 63 6b 65 | 74 20 69 74 73 65 6c 66 |he packe|t itself|
|000017d0| 20 69 73 20 65 6e 63 6f | 64 65 64 20 73 6f 20 74 | is enco|ded so t|
|000017e0| 68 61 74 20 52 45 51 2c | 20 20 41 43 4b 2c 20 20 |hat REQ,|  ACK,  |
|000017f0| 61 6e 64 20 20 45 4e 44 | 20 20 6e 65 76 65 72 0d |and  END|  never.|
|00001800| 20 20 20 20 20 61 70 70 | 65 61 72 20 20 69 6e 20 |     app|ear  in |
|00001810| 20 74 68 65 20 20 74 65 | 78 74 2e 20 20 54 68 69 | the  te|xt.  Thi|
|00001820| 73 20 69 73 20 64 6f 6e | 65 20 62 79 20 70 65 72 |s is don|e by per|
|00001830| 66 6f 72 6d 69 6e 67 20 | 74 68 65 20 66 6f 6c 6c |forming |the foll|
|00001840| 6f 77 69 6e 67 0d 20 20 | 20 20 20 73 75 62 73 74 |owing.  |   subst|
|00001850| 69 74 75 74 69 6f 6e 73 | 3a 0d 20 0d 20 0d 20 0d |itutions|:. . . .|
|00001860| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00001870| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00001880| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00001890| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|000018a0| 20 20 20 20 33 0d 20 20 | 20 20 20 0d 20 20 20 20 |    3.  |   .    |
|000018b0| 20 0d 20 20 20 20 20 32 | 34 32 20 2d 2d 3e 20 32 | .     2|42 --> 2|
|000018c0| 34 32 20 30 0d 20 20 20 | 20 20 32 34 33 20 2d 2d |42 0.   |  243 --|
|000018d0| 3e 20 32 34 32 20 31 0d | 20 20 20 20 20 32 34 34 |> 242 1.|     244|
|000018e0| 20 2d 2d 3e 20 32 34 32 | 20 32 0d 20 20 20 20 20 | --> 242| 2.     |
|000018f0| 32 34 35 20 2d 2d 3e 20 | 32 34 32 20 33 0d 20 20 |245 --> |242 3.  |
|00001900| 20 20 20 0d 20 20 20 20 | 20 20 20 20 20 20 4e 6f |   .    |      No|
|00001910| 74 65 20 20 74 68 61 74 | 20 20 74 72 61 6e 73 66 |te  that|  transf|
|00001920| 65 72 73 20 20 63 61 6e | 20 20 20 6f 63 63 75 72 |ers  can|   occur|
|00001930| 20 20 20 69 6e 20 20 20 | 62 6f 74 68 20 20 20 64 |   in   |both   d|
|00001940| 69 72 65 63 74 69 6f 6e | 73 0d 20 20 20 20 20 73 |irection|s.     s|
|00001950| 69 6d 75 6c 74 61 6e 65 | 6f 75 73 6c 79 2e 20 20 |imultane|ously.  |
|00001960| 48 6f 77 65 76 65 72 20 | 74 68 65 20 41 43 4b 20 |However |the ACK |
|00001970| 73 69 67 6e 61 6c 20 6d | 61 79 20 62 65 20 65 6d |signal m|ay be em|
|00001980| 62 65 64 64 65 64 20 77 | 69 74 68 69 6e 20 61 0d |bedded w|ithin a.|
|00001990| 20 20 20 20 20 64 61 74 | 61 20 70 61 63 6b 65 74 |     dat|a packet|
|000019a0| 20 61 6e 64 20 6d 75 73 | 74 20 62 65 20 65 78 70 | and mus|t be exp|
|000019b0| 6c 69 63 69 74 6c 79 20 | 72 65 6d 6f 76 65 64 3a |licitly |removed:|
|000019c0| 0d 20 20 20 20 0d 20 20 | 20 20 20 49 42 4d 20 77 |.    .  |   IBM w|
|000019d0| 61 6e 74 73 20 74 6f 20 | 73 65 6e 64 20 70 61 63 |ants to |send pac|
|000019e0| 6b 65 74 20 74 6f 20 47 | 61 74 65 77 61 79 3a 20 |ket to G|ateway: |
|000019f0| 20 49 74 20 73 65 6e 64 | 73 20 52 45 51 20 61 6e | It send|s REQ an|
|00001a00| 64 20 77 61 69 74 73 20 | 66 6f 72 20 41 43 4b 2e |d waits |for ACK.|
|00001a10| 0d 20 20 20 20 20 47 61 | 74 65 77 61 79 20 69 73 |.     Ga|teway is|
|00001a20| 20 72 65 61 64 79 20 74 | 6f 20 72 65 63 65 69 76 | ready t|o receiv|
|00001a30| 65 20 70 61 63 6b 65 74 | 3a 20 20 20 49 74 20 73 |e packet|:   It s|
|00001a40| 65 6e 64 73 20 41 43 4b | 2e 0d 20 20 20 20 20 49 |ends ACK|..     I|
|00001a50| 42 4d 20 73 74 61 72 74 | 73 20 73 65 6e 64 69 6e |BM start|s sendin|
|00001a60| 67 20 70 61 63 6b 65 74 | 2e 0d 20 20 20 20 20 47 |g packet|..     G|
|00001a70| 61 74 65 77 61 79 20 77 | 61 6e 74 73 20 74 6f 20 |ateway w|ants to |
|00001a80| 73 65 6e 64 20 70 61 63 | 6b 65 74 20 74 6f 20 49 |send pac|ket to I|
|00001a90| 42 4d 3a 20 20 49 74 20 | 73 65 6e 64 73 20 52 45 |BM:  It |sends RE|
|00001aa0| 51 20 61 6e 64 20 77 61 | 69 74 73 20 66 6f 72 20 |Q and wa|its for |
|00001ab0| 41 43 4b 2e 0d 20 20 20 | 20 20 49 42 4d 20 69 73 |ACK..   |  IBM is|
|00001ac0| 20 72 65 61 64 79 20 74 | 6f 20 72 65 63 65 69 76 | ready t|o receiv|
|00001ad0| 65 20 70 61 63 6b 65 74 | 3a 20 20 20 20 20 20 20 |e packet|:       |
|00001ae0| 49 74 20 73 65 6e 64 73 | 20 41 43 4b 2e 0d 20 20 |It sends| ACK..  |
|00001af0| 20 20 20 49 42 4d 20 20 | 63 6f 6e 74 69 6e 75 65 |   IBM  |continue|
|00001b00| 73 20 20 73 65 6e 64 69 | 6e 67 20 20 69 74 73 20 |s  sendi|ng  its |
|00001b10| 20 70 61 63 6b 65 74 2c | 20 77 68 69 6c 65 20 47 | packet,| while G|
|00001b20| 61 74 65 77 61 79 20 73 | 65 6e 64 73 20 61 20 70 |ateway s|ends a p|
|00001b30| 61 63 6b 65 74 20 74 6f | 0d 20 20 20 20 20 49 42 |acket to|.     IB|
|00001b40| 4d 2e 0d 20 20 20 20 20 | 0d 20 20 20 20 20 20 20 |M..     |.       |
|00001b50| 20 20 20 54 69 6d 65 6f | 75 74 73 20 6d 61 79 20 |   Timeo|uts may |
|00001b60| 6f 63 63 75 72 20 69 66 | 20 74 68 65 20 77 61 69 |occur if| the wai|
|00001b70| 74 20 62 65 74 77 65 65 | 6e 20 61 20 52 45 51 20 |t betwee|n a REQ |
|00001b80| 61 6e 64 20 61 6e 20 41 | 43 4b 20 20 69 73 0d 20 |and an A|CK  is. |
|00001b90| 20 20 20 20 74 6f 6f 20 | 20 6c 6f 6e 67 20 6f 72 |    too | long or|
|00001ba0| 20 6e 6f 20 70 61 63 6b | 65 74 20 63 68 61 72 61 | no pack|et chara|
|00001bb0| 63 74 65 72 73 20 61 72 | 65 20 74 72 61 6e 73 6d |cters ar|e transm|
|00001bc0| 69 74 74 65 64 20 66 6f | 72 20 74 6f 6f 20 6c 6f |itted fo|r too lo|
|00001bd0| 6e 67 20 61 0d 20 20 20 | 20 20 74 69 6d 65 2e 20 |ng a.   |  time. |
|00001be0| 20 49 6e 20 62 6f 74 68 | 20 63 61 73 65 73 20 6e | In both| cases n|
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|00001de0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00001df0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00001e00| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
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+--------+-------------------------+-------------------------+--------+--------+