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|00001d40| 50 20 69 6d 70 6c 65 6d | 65 6e 74 61 74 69 6f 6e |P implem|entation|
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|00001d60| 43 50 0a 6e 6f 64 65 20 | 74 68 61 74 20 69 73 20 |CP.node |that is |
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|00001d80| 79 6f 75 20 6d 61 69 6c | 20 61 6e 64 20 6e 65 77 |you mail| and new|
|00001d90| 73 2e 0a 0a 0a 5c 73 75 | 62 73 65 63 74 69 6f 6e |s....\su|bsection|
|00001da0| 7b 48 6f 77 20 74 6f 20 | 55 73 65 20 55 55 43 50 |{How to |Use UUCP|
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|00001dc0| 25 25 25 25 25 25 25 25 | 25 25 25 25 25 25 25 25 |%%%%%%%%|%%%%%%%%|
|00001dd0| 25 25 25 25 25 25 25 25 | 25 25 25 25 25 25 25 25 |%%%%%%%%|%%%%%%%%|
|00001de0| 25 25 25 25 25 25 25 25 | 25 25 25 25 25 25 25 25 |%%%%%%%%|%%%%%%%%|
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|00004580| 25 25 25 25 25 25 25 25 | 25 25 25 25 25 25 25 25 |%%%%%%%%|%%%%%%%%|
|00004590| 25 25 25 25 25 25 25 25 | 25 25 25 25 25 25 25 25 |%%%%%%%%|%%%%%%%%|
|000045a0| 25 25 25 25 25 25 25 25 | 25 25 25 25 25 25 25 25 |%%%%%%%%|%%%%%%%%|
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|000060d0| 61 74 69 6f 6e 20 6d 61 | 63 68 69 6e 65 2e 20 44 |ation ma|chine. D|
|000060e0| 61 74 61 20 66 6c 6f 77 | 20 62 65 74 77 65 65 6e |ata flow| between|
|000060f0| 20 5c 68 6f 73 74 7b 65 | 72 64 6f 73 7d 20 61 6e | \host{e|rdos} an|
|00006100| 64 0a 5c 68 6f 73 74 7b | 71 75 61 72 6b 7d 20 69 |d.\host{|quark} i|
|00006110| 73 20 73 68 6f 77 6e 20 | 69 6e 20 66 69 67 75 72 |s shown |in figur|
|00006120| 65 7e 5c 72 65 66 7b 69 | 6e 74 72 6f 2e 66 69 67 |e~\ref{i|ntro.fig|
|00006130| 2e 69 70 2d 66 6c 6f 77 | 7d 20 28 57 69 74 68 20 |.ip-flow|} (With |
|00006140| 61 70 6f 6c 6f 67 69 65 | 73 20 74 6f 0a 47 75 79 |apologie|s to.Guy|
|00006150| 20 4c 2e 20 53 74 65 65 | 6c 65 29 2e 0a 0a 0a 5c | L. Stee|le)....\|
|00006160| 62 65 67 69 6e 7b 66 69 | 67 75 72 65 7d 5b 68 74 |begin{fi|gure}[ht|
|00006170| 62 70 5d 0a 20 5c 69 66 | 74 65 78 0a 20 20 5c 69 |bp]. \if|tex. \i|
|00006180| 66 70 73 0a 20 20 20 5c | 62 65 67 69 6e 7b 63 65 |fps. \|begin{ce|
|00006190| 6e 74 65 72 7d 0a 20 20 | 20 20 5c 6d 62 6f 78 7b |nter}. | \mbox{|
|000061a0| 5c 65 70 73 66 66 69 6c | 65 7b 66 69 67 75 72 65 |\epsffil|e{figure|
|000061b0| 73 2f 69 70 2d 66 6c 6f | 77 2e 65 70 73 66 7d 7d |s/ip-flo|w.epsf}}|
|000061c0| 0a 20 20 20 5c 65 6e 64 | 7b 63 65 6e 74 65 72 7d |. \end|{center}|
|000061d0| 0a 20 20 5c 65 6c 73 65 | 0a 20 20 20 5c 62 65 67 |. \else|. \beg|
|000061e0| 69 6e 7b 63 65 6e 74 65 | 72 7d 0a 20 20 20 20 5c |in{cente|r}. \|
|000061f0| 69 6e 70 75 74 7b 69 70 | 2d 66 6c 6f 77 2e 65 65 |input{ip|-flow.ee|
|00006200| 70 69 63 7d 0a 20 20 20 | 5c 65 6e 64 7b 63 65 6e |pic}. |\end{cen|
|00006210| 74 65 72 7d 0a 20 20 5c | 66 69 0a 20 5c 65 6c 73 |ter}. \|fi. \els|
|00006220| 65 0a 20 5c 66 69 0a 20 | 5c 63 61 70 74 69 6f 6e |e. \fi. |\caption|
|00006230| 7b 0a 20 20 5c 6c 61 62 | 65 6c 7b 69 6e 74 72 6f |{. \lab|el{intro|
|00006240| 2e 66 69 67 2e 69 70 2d | 66 6c 6f 77 7d 0a 20 20 |.fig.ip-|flow}. |
|00006250| 54 68 65 20 74 68 72 65 | 65 20 73 74 65 70 73 20 |The thre|e steps |
|00006260| 6f 66 20 73 65 6e 64 69 | 6e 67 20 61 20 64 61 74 |of sendi|ng a dat|
|00006270| 61 67 72 61 6d 20 66 72 | 6f 6d 20 5c 68 6f 73 74 |agram fr|om \host|
|00006280| 7b 65 72 64 6f 73 7d 0a | 20 20 74 6f 20 5c 68 6f |{erdos}.| to \ho|
|00006290| 73 74 7b 71 75 61 72 6b | 7d 2e 0a 20 7d 0a 5c 65 |st{quark|}.. }.\e|
|000062a0| 6e 64 7b 66 69 67 75 72 | 65 7d 0a 0a 0a 5c 69 6e |nd{figur|e}...\in|
|000062b0| 64 65 78 7b 49 50 21 72 | 6f 75 74 69 6e 67 7d 0a |dex{IP!r|outing}.|
|000062c0| 54 68 69 73 20 73 63 68 | 65 6d 65 20 6f 66 20 64 |This sch|eme of d|
|000062d0| 69 72 65 63 74 69 6e 67 | 20 64 61 74 61 20 74 6f |irecting| data to|
|000062e0| 20 61 20 72 65 6d 6f 74 | 65 20 68 6f 73 74 20 69 | a remot|e host i|
|000062f0| 73 20 63 61 6c 6c 65 64 | 20 5c 65 6d 70 68 7b 72 |s called| \emph{r|
|00006300| 6f 75 74 69 6e 67 7d 2c | 0a 61 6e 64 20 70 61 63 |outing},|.and pac|
|00006310| 6b 65 74 73 20 61 72 65 | 20 6f 66 74 65 6e 20 72 |kets are| often r|
|00006320| 65 66 65 72 72 65 64 20 | 74 6f 20 61 73 20 5c 65 |eferred |to as \e|
|00006330| 6d 70 68 7b 64 61 74 61 | 67 72 61 6d 73 7d 20 69 |mph{data|grams} i|
|00006340| 6e 20 74 68 69 73 20 63 | 6f 6e 74 65 78 74 2e 0a |n this c|ontext..|
|00006350| 54 6f 20 66 61 63 69 6c | 69 74 61 74 65 20 74 68 |To facil|itate th|
|00006360| 69 6e 67 73 2c 20 64 61 | 74 61 67 72 61 6d 20 65 |ings, da|tagram e|
|00006370| 78 63 68 61 6e 67 65 20 | 69 73 20 67 6f 76 65 72 |xchange |is gover|
|00006380| 6e 65 64 20 62 79 20 61 | 20 73 69 6e 67 6c 65 20 |ned by a| single |
|00006390| 70 72 6f 74 6f 63 6f 6c | 0a 74 68 61 74 20 69 73 |protocol|.that is|
|000063a0| 20 69 6e 64 65 70 65 6e | 64 65 6e 74 20 6f 66 20 | indepen|dent of |
|000063b0| 74 68 65 20 68 61 72 64 | 77 61 72 65 20 75 73 65 |the hard|ware use|
|000063c0| 64 3a 20 49 50 2c 20 6f | 72 20 5c 65 6d 70 68 7b |d: IP, o|r \emph{|
|000063d0| 49 6e 74 65 72 6e 65 74 | 0a 50 72 6f 74 6f 63 6f |Internet|.Protoco|
|000063e0| 6c 7d 2e 20 20 49 6e 20 | 63 68 61 70 74 65 72 7e |l}. In |chapter~|
|000063f0| 5c 72 65 66 7b 74 63 70 | 69 70 7d 2c 20 77 65 20 |\ref{tcp|ip}, we |
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