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100% file Mailbox text, 1st line "From almes@rice.edu Mon Mar 25 09:28:07 1991", ASCII text default
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|00002220| 20 74 6f 20 63 6f 6e 73 | 69 64 65 72 20 72 65 61 | to cons|ider rea|
|00002230| 6c 2d 6c 69 66 65 20 73 | 63 65 6e 61 72 69 6f 73 |l-life s|cenarios|
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|00002280| 49 6e 20 74 68 65 20 66 | 6f 6c 6c 6f 77 69 6e 67 |In the f|ollowing|
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|00002370| 73 2e 0a 0a 09 45 78 61 | 6d 70 6c 65 20 31 3a 0a |s....Exa|mple 1:.|
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|00002500| 72 65 63 65 69 76 65 64 | 20 66 72 6f 6d 20 49 53 |received| from IS|
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|00002540| 50 41 0a 09 64 20 61 6e | 64 20 49 53 20 44 20 66 |PA..d an|d IS D f|
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|00002560| 65 74 20 74 6f 20 45 53 | 20 43 2e 0a 0a 09 45 78 |et to ES| C....Ex|
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|000025a0| 20 20 41 73 20 69 6e 20 | 65 78 61 6d 70 6c 65 20 | As in |example |
|000025b0| 31 2c 20 45 53 20 41 20 | 6b 6e 6f 77 73 0a 09 61 |1, ES A |knows..a|
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|00002620| 20 53 4e 50 41 20 64 2e | 20 49 53 20 44 20 68 61 | SNPA d.| IS D ha|
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|00002770| 20 20 49 53 20 44 20 6e | 6f 74 69 66 69 65 73 20 | IS D n|otifies |
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|000027e0| 20 62 79 20 73 65 6e 64 | 69 6e 67 20 70 61 63 6b | by send|ing pack|
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|000028d0| 73 61 6d 65 0a 09 73 75 | 62 6e 65 74 77 6f 72 6b |same..su|bnetwork|
|000028e0| 2a 20 61 73 20 45 53 20 | 41 2e 20 54 68 65 20 6f |* as ES |A. The o|
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|00002920| 20 66 6f 72 20 45 53 20 | 42 2e 20 20 45 53 20 41 | for ES |B. ES A|
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|000029b0| 65 6e 20 74 6f 20 45 53 | 48 20 50 44 55 73 20 73 |en to ES|H PDUs s|
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|000029d0| 74 77 6f 72 6b 2e 20 20 | 49 66 20 45 53 20 41 0a |twork. |If ES A.|
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|000029f0| 74 20 77 6f 75 6c 64 20 | 6b 6e 6f 77 20 74 68 65 |t would |know the|
|00002a00| 20 53 4e 50 41 20 6f 66 | 20 42 2e 20 45 53 20 41 | SNPA of| B. ES A|
|00002a10| 20 63 6f 75 6c 64 20 74 | 68 65 6e 20 74 72 61 6e | could t|hen tran|
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|00002a30| 20 64 69 72 65 63 74 6c | 79 20 74 6f 20 45 53 20 | directl|y to ES |
|00002a40| 42 20 61 74 20 53 4e 50 | 41 20 62 2e 0a 0a 09 45 |B at SNP|A b....E|
|00002a50| 78 61 6d 70 6c 65 20 33 | 3a 0a 09 53 69 6d 69 6c |xample 3|:..Simil|
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|00002a90| 6e 64 20 74 6f 20 45 53 | 20 42 2e 0a 09 49 6e 20 |nd to ES| B...In |
|00002aa0| 61 64 64 69 74 69 6f 6e | 2c 20 45 53 20 41 20 6b |addition|, ES A k|
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|00002ad0| 62 6e 65 74 77 6f 72 6b | 2e 0a 09 46 75 72 74 68 |bnetwork|...Furth|
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|00002af0| 68 61 74 20 45 53 20 41 | 20 64 6f 65 73 20 6e 6f |hat ES A| does no|
|00002b00| 74 20 65 61 76 65 73 64 | 72 6f 70 20 61 6e 64 20 |t eavesd|rop and |
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|00002b30| 53 20 41 20 64 65 74 65 | 72 6d 69 6e 65 20 74 68 |S A dete|rmine th|
|00002b40| 65 20 53 4e 50 41 20 6f | 66 20 45 53 20 42 3f 20 |e SNPA o|f ES B? |
|00002b50| 49 6e 20 74 68 69 73 20 | 73 69 74 75 61 74 69 6f |In this |situatio|
|00002b60| 6e 2c 0a 09 45 53 20 41 | 20 77 69 6c 6c 20 69 6e |n,..ES A| will in|
|00002b70| 76 6f 6b 65 20 61 20 66 | 75 6e 63 74 69 6f 6e 20 |voke a f|unction |
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|00002b90| 74 6f 63 6f 6c 20 63 61 | 6c 6c 65 64 20 71 75 65 |tocol ca|lled que|
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|00002bc0| 45 53 20 41 20 77 69 6c | 6c 20 2a 62 72 6f 61 64 |ES A wil|l *broad|
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|00002be0| 20 70 61 63 6b 65 74 0a | 09 74 6f 20 61 6c 6c 20 | packet.|.to all |
|00002bf0| 45 53 73 20 6f 6e 20 74 | 68 65 20 73 75 62 6e 65 |ESs on t|he subne|
|00002c00| 74 77 6f 72 6b 2e 20 20 | 57 68 65 6e 20 45 53 20 |twork. |When ES |
|00002c10| 42 20 72 65 63 65 69 76 | 65 73 20 74 68 69 73 20 |B receiv|es this |
|00002c20| 62 72 6f 61 64 63 61 73 | 74 65 64 0a 09 70 61 63 |broadcas|ted..pac|
|00002c30| 6b 65 74 2c 20 69 74 20 | 77 69 6c 6c 20 6e 6f 74 |ket, it |will not|
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|00002c50| 61 63 6b 65 74 20 69 73 | 20 61 20 64 61 74 61 20 |acket is| a data |
|00002c60| 70 61 63 6b 65 74 20 73 | 65 6e 74 20 74 6f 20 61 |packet s|ent to a|
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|00002c80| 20 61 64 64 72 65 73 73 | 3b 20 32 29 20 74 68 61 | address|; 2) tha|
|00002c90| 74 20 74 68 65 20 64 65 | 73 74 69 6e 61 74 69 6f |t the de|stinatio|
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|00002cb0| 66 20 74 68 65 0a 09 62 | 72 6f 61 64 63 61 73 74 |f the..b|roadcast|
|00002cc0| 65 64 20 70 61 63 6b 65 | 74 20 69 73 20 45 53 20 |ed packe|t is ES |
|00002cd0| 42 2e 20 20 49 6e 20 74 | 68 69 73 20 63 61 73 65 |B. In t|his case|
|00002ce0| 2c 20 45 53 20 42 20 77 | 69 6c 6c 20 67 65 6e 65 |, ES B w|ill gene|
|00002cf0| 72 61 74 65 20 61 6e 0a | 09 45 53 48 20 70 61 63 |rate an.|.ESH pac|
|00002d00| 6b 65 74 20 61 6e 64 20 | 73 65 6e 64 20 69 74 20 |ket and |send it |
|00002d10| 64 69 72 65 63 74 6c 79 | 20 74 6f 20 45 53 20 41 |directly| to ES A|
|00002d20| 2e 20 20 54 68 69 73 20 | 70 61 63 6b 65 74 20 77 |. This |packet w|
|00002d30| 69 6c 6c 20 69 6e 66 6f | 72 6d 0a 09 45 53 20 41 |ill info|rm..ES A|
|00002d40| 20 6f 66 20 74 68 65 20 | 53 4e 50 41 20 6f 66 20 | of the |SNPA of |
|00002d50| 45 53 20 42 2e 0a 0a 09 | 41 20 63 6f 6d 6d 6f 6e |ES B....|A common|
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|00002db0| 53 48 20 70 61 63 6b 65 | 74 73 2c 20 68 6f 77 20 |SH packe|ts, how |
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|00002dd0| 68 65 20 45 53 48 20 73 | 65 6e 74 0a 09 64 69 72 |he ESH s|ent..dir|
|00002de0| 65 63 74 6c 79 20 62 79 | 20 45 53 20 42 20 3f 22 |ectly by| ES B ?"|
|00002df0| 20 54 68 65 20 6b 65 79 | 20 74 6f 20 74 68 65 20 | The key| to the |
|00002e00| 61 6e 73 77 65 72 20 69 | 73 20 53 4e 50 41 20 61 |answer i|s SNPA a|
|00002e10| 64 64 72 65 73 73 65 73 | 2e 20 20 57 68 65 6e 0a |ddresses|. When.|
|00002e20| 09 61 6e 20 45 53 20 65 | 61 76 65 73 64 72 6f 70 |.an ES e|avesdrop|
|00002e30| 73 2c 20 69 74 20 2a 65 | 6e 61 62 6c 65 73 2a 20 |s, it *e|nables* |
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|00002e50| 20 70 61 63 6b 65 74 73 | 20 61 64 64 72 65 73 73 | packets| address|
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|00002e70| 63 61 73 74 20 61 64 64 | 72 65 73 73 20 22 61 6c |cast add|ress "al|
|00002e80| 6c 20 69 6e 74 65 72 6d | 65 64 69 61 74 65 20 73 |l interm|ediate s|
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|00002ec0| 6b 65 74 73 20 74 6f 20 | 74 68 65 20 6d 75 6c 74 |kets to |the mult|
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|00002ef0| 20 73 79 73 74 65 6d 73 | 22 29 2e 20 20 20 57 68 | systems|"). Wh|
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|00002fa0| 61 62 6c 65 64 2e 0a 0a | 50 44 55 20 66 6f 72 6d |abled...|PDU form|
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|00003100| 6f 72 65 20 74 68 61 6e | 20 31 20 4e 53 41 50 20 |ore than| 1 NSAP |
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|00003710| 6f 74 6f 63 6f 6c 20 28 | 52 46 43 20 37 39 32 29 |otocol (|RFC 792)|
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|00003780| 65 69 74 68 65 72 20 61 | 6e 20 45 53 20 6f 72 20 |either a|n ES or |
|00003790| 49 53 0a 09 77 68 65 72 | 65 61 73 20 61 6e 20 49 |IS..wher|eas an I|
|000037a0| 43 4d 50 20 72 65 64 69 | 72 65 63 74 20 63 61 6e |CMP redi|rect can|
|000037b0| 20 6f 6e 6c 79 20 72 65 | 66 65 72 20 74 6f 20 61 | only re|fer to a|
|000037c0| 20 67 61 74 65 77 61 79 | 2e 0a 0a 0a 3d 3d 3d 3d | gateway|....====|
|000037d0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000037e0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|000037f0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003800| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003810| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 0a 0a 46 69 67 75 72 |========|=..Figur|
|00003820| 65 20 31 0a 0a 20 20 20 | 20 20 20 20 20 20 20 2b |e 1.. | +|
|00003830| 2d 2d 2d 2d 2d 2d 2d 2b | 0a 20 20 20 20 20 20 20 |-------+|. |
|00003840| 20 20 20 7c 20 20 20 20 | 20 20 20 7c 0a 20 20 20 | | | |. |
|00003850| 20 20 20 20 20 20 20 7c | 20 45 53 20 41 20 20 7c | || ES A ||
|00003860| 2d 2d 2d 2d 2d 2d 7c 0a | 20 20 20 20 20 20 20 20 |------|.| |
|00003870| 20 20 7c 20 20 20 20 20 | 20 20 7c 20 20 20 20 20 | | | | |
|00003880| 20 7c 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | | |
|00003890| 20 0a 20 20 20 20 20 20 | 20 20 20 20 2b 2d 2d 2d | . | +---|
|000038a0| 2d 2d 2d 2d 2b 20 20 20 | 20 20 20 7c 20 20 20 20 |----+ | | |
|000038b0| 20 20 20 20 20 20 20 20 | 20 20 20 0a 20 20 20 20 | | . |
|000038c0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000038d0| 20 20 20 20 20 7c 20 20 | 20 20 20 20 20 20 20 20 | | | |
|000038e0| 20 20 20 20 20 0a 20 20 | 20 20 20 20 20 20 20 20 | . | |
|000038f0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 7c | | ||
|00003900| 20 20 20 2b 2d 2d 2d 2d | 2d 2d 2d 2b 20 20 20 7c | +----|---+ ||
|00003910| 0a 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |. | |
|00003920| 20 20 20 20 20 20 20 20 | 20 20 7c 20 20 20 7c 20 | | | | |
|00003930| 20 20 20 20 20 20 7c 20 | 20 20 7c 0a 20 20 20 20 | | | |. |
|00003940| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00003950| 20 20 20 20 20 7c 2d 2d | 2d 7c 20 49 53 20 44 20 | |--|-| IS D |
|00003960| 20 7c 2d 2d 2d 7c 0a 20 | 20 20 20 20 20 20 20 20 | |---|. | |
|00003970| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00003980| 7c 20 20 20 7c 20 20 20 | 20 20 20 20 7c 20 20 20 || | | | |
|00003990| 7c 0a 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 ||. | |
|000039a0| 20 20 20 20 20 20 20 20 | 20 20 20 7c 20 20 20 2b | | | +|
|000039b0| 2d 2d 2d 2d 2d 2d 2d 2b | 20 20 20 7c 20 20 20 20 |-------+| | |
|000039c0| 20 2b 2d 2d 2d 2d 2d 2d | 2d 2b 0a 20 20 20 20 20 | +------|-+. |
|000039d0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000039e0| 20 20 20 20 7c 20 20 20 | 20 20 20 20 20 20 20 20 | | | |
|000039f0| 20 20 20 20 7c 20 20 20 | 20 20 7c 20 20 20 20 20 | | | | |
|00003a00| 20 20 7c 0a 20 20 20 20 | 20 20 20 20 20 20 2b 2d | |. | +-|
|00003a10| 2d 2d 2d 2d 2d 2d 2b 20 | 20 20 20 20 20 7c 20 20 |------+ | | |
|00003a20| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 7c 2d 2d | | |--|
|00003a30| 2d 2d 2d 7c 20 45 53 20 | 43 20 20 7c 0a 20 20 20 |---| ES |C |. |
|00003a40| 20 20 20 20 20 20 20 7c | 20 20 20 20 20 20 20 7c | || ||
|00003a50| 20 20 20 20 20 20 7c 20 | 20 20 20 20 20 20 20 20 | | | |
|00003a60| 20 20 20 20 20 20 20 20 | 20 20 20 20 7c 20 20 20 | | | |
|00003a70| 20 20 20 20 7c 0a 20 20 | 20 20 20 20 20 20 20 20 | |. | |
|00003a80| 7c 20 45 53 20 42 20 20 | 7c 2d 2d 2d 2d 2d 2d 7c || ES B ||------||
|00003a90| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00003aa0| 20 20 20 20 20 2b 2d 2d | 2d 2d 2d 2d 2d 2b 0a 20 | +--|-----+. |
|00003ab0| 20 20 20 20 20 20 20 20 | 20 7c 20 20 20 20 20 20 | | | |
|00003ac0| 20 7c 0a 20 20 20 20 20 | 20 20 20 20 20 2b 2d 2d | |. | +--|
|00003ad0| 2d 2d 2d 2d 2d 2b 0a 0a | 3d 3d 3d 3d 3d 3d 3d 3d |-----+..|========|
|00003ae0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003af0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003b00| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003b10| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003b20| 3d 3d 3d 3d 3d 0a 0a 46 | 69 67 75 72 65 20 32 0a |=====..F|igure 2.|
|00003b30| 0a 09 54 68 65 20 45 53 | 48 20 50 61 63 6b 65 74 |..The ES|H Packet|
|00003b40| 20 46 6f 72 6d 61 74 0a | 0a 2b 2d 2d 2d 2d 2d 2d | Format.|.+------|
|00003b50| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003b60| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003b70| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003b80| 2d 2d 2d 2d 2d 2d 2d 2b | 0a 7c 20 20 20 20 20 20 |-------+|.| |
|00003b90| 20 20 20 20 20 20 20 20 | 20 4e 65 74 77 6f 72 6b | | Network|
|00003ba0| 20 4c 61 79 65 72 20 50 | 72 6f 74 6f 63 6f 6c 20 | Layer P|rotocol |
|00003bb0| 49 64 65 6e 74 69 66 69 | 65 72 0a 2b 2d 2d 2d 2d |Identifi|er.+----|
|00003bc0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003bd0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003be0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003bf0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2b 0a 7c 09 09 09 09 |--------|-+.|....|
|00003c00| 4c 65 6e 67 74 68 20 49 | 6e 64 69 63 61 74 6f 72 |Length I|ndicator|
|00003c10| 0a 2b 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |.+------|--------|
|00003c20| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003c30| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003c40| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2b |--------|-------+|
|00003c50| 0a 7c 09 09 09 09 56 65 | 72 73 69 6f 6e 2f 50 72 |.|....Ve|rsion/Pr|
|00003c60| 6f 74 6f 63 6f 6c 20 49 | 64 20 65 78 74 65 6e 73 |otocol I|d extens|
|00003c70| 69 6f 6e 0a 2b 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |ion.+---|--------|
|00003c80| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003c90| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003ca0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003cb0| 2d 2d 2b 0a 7c 09 09 09 | 09 52 65 73 65 72 76 65 |--+.|...|.Reserve|
|00003cc0| 64 0a 2b 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |d.+-----|--------|
|00003cd0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003ce0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003cf0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003d00| 2b 0a 7c 20 20 30 20 20 | 7c 20 30 20 7c 20 30 20 |+.| 0 || 0 | 0 |
|00003d10| 7c 20 20 20 54 79 70 65 | 20 6f 66 20 50 61 63 6b || Type| of Pack|
|00003d20| 65 74 0a 2b 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |et.+----|--------|
|00003d30| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003d40| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003d50| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003d60| 2d 2b 0a 7c 20 20 20 20 | 20 20 20 20 20 20 20 20 |-+.| | |
|00003d70| 20 20 20 48 6f 6c 64 69 | 6e 67 20 0a 7c 20 20 20 | Holdi|ng .| |
|00003d80| 20 20 20 20 20 20 20 20 | 20 20 20 20 54 69 6d 65 | | Time|
|00003d90| 0a 2b 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |.+------|--------|
|00003da0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003db0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003dc0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2b |--------|-------+|
|00003dd0| 0a 7c 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |.| | |
|00003de0| 20 43 68 65 63 6b 73 75 | 6d 0a 7c 0a 2b 2d 2d 2d | Checksu|m.|.+---|
|00003df0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003e00| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003e10| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003e20| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2b 0a 7c 20 20 20 |--------|--+.| |
|00003e30| 20 20 20 20 20 20 20 20 | 20 20 20 20 4e 75 6d 62 | | Numb|
|00003e40| 65 72 20 6f 66 20 53 6f | 75 72 63 65 20 41 64 64 |er of So|urce Add|
|00003e50| 72 65 73 73 65 73 0a 2b | 2d 2d 2d 2d 2d 2d 2d 2d |resses.+|--------|
|00003e60| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003e70| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003e80| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003e90| 2d 2d 2d 2d 2d 2b 0a 7c | 20 20 20 20 20 20 20 20 |-----+.|| |
|00003ea0| 20 20 20 20 20 20 20 53 | 6f 75 72 63 65 20 41 64 | S|ource Ad|
|00003eb0| 64 72 65 73 73 20 4c 65 | 6e 67 74 68 0a 2b 2d 2d |dress Le|ngth.+--|
|00003ec0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003ed0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003ee0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003ef0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2b 0a 2f 0a 20 |--------|---+./. |
|00003f00| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 53 | | S|
|00003f10| 6f 75 72 63 65 20 41 64 | 64 72 65 73 73 0a 2f 0a |ource Ad|dress./.|
|00003f20| 7c 0a 2b 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d ||.+-----|--------|
|00003f30| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003f40| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003f50| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003f60| 2b 0a 2e 0a 2e 0a 2b 2d | 2d 2d 2d 2d 2d 2d 2d 2d |+.....+-|--------|
|00003f70| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003f80| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003f90| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00003fa0| 2d 2d 2d 2d 2b 0a 0a 0a | 3d 3d 3d 3d 3d 3d 3d 3d |----+...|========|
|00003fb0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003fc0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003fd0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003fe0| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |========|========|
|00003ff0| 3d 3d 3d 3d 3d 0a 0a 46 | 69 67 75 72 65 20 33 0a |=====..F|igure 3.|
|00004000| 0a 09 54 68 65 20 49 53 | 48 20 50 61 63 6b 65 74 |..The IS|H Packet|
|00004010| 20 46 6f 72 6d 61 74 0a | 0a 2b 2d 2d 2d 2d 2d 2d | Format.|.+------|
|00004020| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004030| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004040| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004050| 2d 2d 2d 2d 2d 2d 2d 2b | 0a 7c 20 20 20 20 20 20 |-------+|.| |
|00004060| 20 20 20 20 20 20 20 20 | 20 4e 65 74 77 6f 72 6b | | Network|
|00004070| 20 4c 61 79 65 72 20 50 | 72 6f 74 6f 63 6f 6c 20 | Layer P|rotocol |
|00004080| 49 64 65 6e 74 69 66 69 | 65 72 0a 2b 2d 2d 2d 2d |Identifi|er.+----|
|00004090| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000040a0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000040b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000040c0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2b 0a 7c 09 09 09 09 |--------|-+.|....|
|000040d0| 4c 65 6e 67 74 68 20 49 | 6e 64 69 63 61 74 6f 72 |Length I|ndicator|
|000040e0| 0a 2b 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |.+------|--------|
|000040f0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004100| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004110| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2b |--------|-------+|
|00004120| 0a 7c 09 09 09 09 56 65 | 72 73 69 6f 6e 2f 50 72 |.|....Ve|rsion/Pr|
|00004130| 6f 74 6f 63 6f 6c 20 49 | 64 20 65 78 74 65 6e 73 |otocol I|d extens|
|00004140| 69 6f 6e 0a 2b 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |ion.+---|--------|
|00004150| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004160| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004170| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004180| 2d 2d 2b 0a 7c 09 09 09 | 09 52 65 73 65 72 76 65 |--+.|...|.Reserve|
|00004190| 64 0a 2b 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |d.+-----|--------|
|000041a0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000041b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000041c0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000041d0| 2b 0a 7c 20 20 30 20 20 | 7c 20 30 20 7c 20 30 20 |+.| 0 || 0 | 0 |
|000041e0| 7c 20 20 20 54 79 70 65 | 20 6f 66 20 50 61 63 6b || Type| of Pack|
|000041f0| 65 74 0a 2b 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |et.+----|--------|
|00004200| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004210| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004220| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004230| 2d 2b 0a 7c 20 20 20 20 | 20 20 20 20 20 20 20 20 |-+.| | |
|00004240| 20 20 20 48 6f 6c 64 69 | 6e 67 20 0a 7c 20 20 20 | Holdi|ng .| |
|00004250| 20 20 20 20 20 20 20 20 | 20 20 20 20 54 69 6d 65 | | Time|
|00004260| 0a 2b 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |.+------|--------|
|00004270| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004280| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004290| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2b |--------|-------+|
|000042a0| 0a 7c 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |.| | |
|000042b0| 20 43 68 65 63 6b 73 75 | 6d 0a 7c 0a 2b 2d 2d 2d | Checksu|m.|.+---|
|000042c0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000042d0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000042e0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000042f0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2b 0a 7c 20 20 20 |--------|--+.| |
|00004300| 20 20 20 20 20 20 20 20 | 20 20 20 20 4e 65 74 77 | | Netw|
|00004310| 6f 72 6b 20 45 6e 74 69 | 74 79 20 54 69 74 6c 65 |ork Enti|ty Title|
|00004320| 20 4c 65 6e 67 74 68 0a | 2b 2d 2d 2d 2d 2d 2d 2d | Length.|+-------|
|00004330| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004340| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004350| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00004360| 2d 2d 2d 2d 2d 2d 2b 0a | 2f 0a 20 20 20 20 20 20 |------+.|/. |
|00004370| 20 20 20 20 20 20 20 20 | 20 20 4e 65 74 77 6f 72 | | Networ|
|00004380| 6b 20 45 6e 74 69 74 79 | 20 54 69 74 6c 65 0a 2f |k Entity| Title./|
|00004390| 0a 7c 0a 2b 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |.|.+----|--------|
|000043a0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000043b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000043c0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000043d0| 2d 2b 0a 0a 0a | |-+... | |
+--------+-------------------------+-------------------------+--------+--------+