home *** CD-ROM | disk | FTP | other *** search
MacBinary | 1993-01-04 | 4.1 KB | [TEXT/ttxt] |
open in:
MacOS 8.1
|
Win98
|
DOS
browse contents |
view JSON data
|
view as text
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, Mon Jan 4 09:52:04 1993, modified Mon Jan 4 09:52:04 1993, creator SimpleText, type ASCII, 3691 bytes "is_es Command Documentation" , at 0xeeb 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 1b 69 73 5f 65 73 20 | 43 6f 6d 6d 61 6e 64 20 |..is_es |Command |
|00000010| 44 6f 63 75 6d 65 6e 74 | 61 74 69 6f 6e 00 00 00 |Document|ation...|
|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 0e 6b 00 | 00 01 1e a7 6d ff 94 a7 |......k.|....m...|
|00000060| 6d ff 94 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |m.......|........|
|00000070| 00 00 00 00 00 00 00 00 | 00 00 81 81 ed e5 00 00 |........|........|
|00000080| 49 6e 74 65 72 6d 65 64 | 69 61 74 65 20 73 79 73 |Intermed|iate sys|
|00000090| 74 65 6d 20 74 6f 20 45 | 6e 64 2d 73 79 73 74 65 |tem to E|nd-syste|
|000000a0| 6d 20 28 49 53 2d 45 53 | 29 3a 20 46 75 6e 63 74 |m (IS-ES|): Funct|
|000000b0| 69 6f 6e 61 6c 20 44 65 | 73 63 72 69 70 74 69 6f |ional De|scriptio|
|000000c0| 6e 0d 20 0d 4c 65 74 27 | 73 20 61 73 73 75 6d 65 |n. .Let'|s assume|
|000000d0| 20 74 68 61 74 20 77 65 | 20 68 61 76 65 20 61 20 | that we| have a |
|000000e0| 64 79 6e 61 6d 69 63 61 | 6c 6c 79 20 72 6f 75 74 |dynamica|lly rout|
|000000f0| 65 64 20 6e 65 74 77 6f | 72 6b 20 74 6f 67 65 74 |ed netwo|rk toget|
|00000100| 68 65 72 20 61 6e 64 20 | 20 74 77 6f 0d 73 74 61 |her and | two.sta|
|00000110| 74 69 6f 6e 73 20 61 72 | 65 20 74 72 79 69 6e 67 |tions ar|e trying|
|00000120| 20 74 6f 20 63 6f 6d 6d | 75 6e 69 63 61 74 65 20 | to comm|unicate |
|00000130| 61 63 72 6f 73 73 20 61 | 20 63 68 61 69 6e 20 6f |across a| chain o|
|00000140| 66 20 69 6e 74 65 72 2d | 63 6f 6e 6e 65 63 74 65 |f inter-|connecte|
|00000150| 64 20 49 53 2e 0d 49 67 | 6e 6f 72 65 20 66 6f 72 |d IS..Ig|nore for|
|00000160| 20 61 20 6d 6f 6d 65 6e | 74 20 68 6f 77 20 74 68 | a momen|t how th|
|00000170| 65 20 66 69 72 73 74 20 | 45 53 20 66 69 6e 64 73 |e first |ES finds|
|00000180| 20 61 6e 20 49 53 20 74 | 6f 20 66 6f 72 77 61 72 | an IS t|o forwar|
|00000190| 64 20 20 70 61 63 6b 65 | 74 73 20 20 74 6f 0d 74 |d packe|ts to.t|
|000001a0| 68 65 20 20 64 65 73 74 | 69 6e 61 74 69 6f 6e 3b |he dest|ination;|
|000001b0| 20 6c 65 74 73 20 63 6f | 6e 73 69 64 65 72 20 68 | lets co|nsider h|
|000001c0| 6f 77 20 74 68 65 20 6c | 61 73 74 20 49 53 20 69 |ow the l|ast IS i|
|000001d0| 6e 20 74 68 65 20 72 6f | 75 74 65 20 73 65 74 73 |n the ro|ute sets|
|000001e0| 20 75 70 20 74 68 65 0d | 66 69 6e 61 6c 20 68 6f | up the.|final ho|
|000001f0| 70 20 74 6f 20 74 68 65 | 20 64 65 73 74 69 6e 61 |p to the| destina|
|00000200| 74 69 6f 6e 20 45 53 20 | 20 61 6e 64 20 20 65 6e |tion ES | and en|
|00000210| 61 62 6c 65 73 20 20 74 | 68 65 20 20 72 6f 75 74 |ables t|he rout|
|00000220| 65 20 20 62 61 63 6b 20 | 20 74 6f 20 20 74 68 65 |e back | to the|
|00000230| 0d 73 6f 75 72 63 65 2e | 0d 20 0d 46 6f 72 20 20 |.source.|. .For |
|00000240| 65 61 73 65 20 20 6f 66 | 20 20 64 65 73 63 72 69 |ease of| descri|
|00000250| 70 74 69 6f 6e 2c 20 63 | 6f 6e 73 69 64 65 72 20 |ption, c|onsider |
|00000260| 74 68 65 20 73 69 6d 70 | 6c 65 20 63 61 73 65 20 |the simp|le case |
|00000270| 6f 66 20 74 77 6f 20 45 | 53 20 74 72 79 69 6e 67 |of two E|S trying|
|00000280| 20 74 6f 0d 63 6f 6d 6d | 75 6e 69 63 61 74 65 20 | to.comm|unicate |
|00000290| 74 68 72 6f 75 67 68 20 | 61 20 73 69 6e 67 6c 65 |through |a single|
|000002a0| 20 49 53 20 28 65 78 74 | 65 6e 64 69 6e 67 20 74 | IS (ext|ending t|
|000002b0| 6f 20 6d 75 6c 74 69 70 | 6c 65 20 49 53 20 77 6f |o multip|le IS wo|
|000002c0| 72 6b 73 20 6a 75 73 74 | 20 74 68 65 0d 73 61 6d |rks just| the.sam|
|000002d0| 65 20 77 61 79 2c 20 3a | 2d 29 20 64 65 72 69 76 |e way, :|-) deriv|
|000002e0| 61 74 69 6f 6e 20 69 73 | 20 6c 65 66 74 20 74 6f |ation is| left to|
|000002f0| 20 74 68 65 20 72 65 61 | 64 65 72 2e 0d 20 0d 54 | the rea|der.. .T|
|00000300| 68 72 65 65 20 6e 6f 64 | 65 73 20 41 2c 42 2c 61 |hree nod|es A,B,a|
|00000310| 6e 64 20 43 2e 20 20 41 | 20 75 73 65 73 20 42 20 |nd C. A| uses B |
|00000320| 61 73 20 61 20 67 61 74 | 65 77 61 79 20 74 6f 20 |as a gat|eway to |
|00000330| 43 2e 0d 20 0d 49 6e 20 | 74 68 65 20 70 72 65 2d |C.. .In |the pre-|
|00000340| 72 6f 75 74 69 6e 67 20 | 63 61 73 65 2c 20 74 68 |routing |case, th|
|00000350| 65 20 66 6f 6c 6c 6f 77 | 69 6e 67 20 6d 65 73 73 |e follow|ing mess|
|00000360| 61 67 65 20 65 78 63 68 | 61 6e 67 65 20 77 6f 75 |age exch|ange wou|
|00000370| 6c 64 20 6f 63 63 75 72 | 20 69 66 20 41 0d 61 74 |ld occur| if A.at|
|00000380| 74 65 6d 70 74 65 64 20 | 74 6f 20 63 6f 6d 6d 75 |tempted |to commu|
|00000390| 6e 69 63 61 74 65 20 77 | 69 74 68 20 43 2e 0d 20 |nicate w|ith C.. |
|000003a0| 0d 20 20 20 20 20 20 20 | 20 20 20 20 20 20 41 20 |. | A |
|000003b0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000003c0| 20 20 20 20 20 20 20 42 | 20 20 20 20 20 20 20 20 | B| |
|000003d0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 43 | | C|
|000003e0| 0d 20 0d 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |. . | |
|000003f0| 41 52 50 20 72 65 71 75 | 65 73 74 2c 20 74 61 72 |ARP requ|est, tar|
|00000400| 67 65 74 20 42 2d 3e 0d | 20 20 20 20 20 20 20 20 |get B->.| |
|00000410| 20 20 20 20 20 20 20 20 | 20 20 3c 2d 20 41 52 50 | | <- ARP|
|00000420| 20 72 65 70 6c 79 20 66 | 72 6f 6d 20 42 2d 41 0d | reply f|rom B-A.|
|00000430| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 49 50 20 | | IP |
|00000440| 5b 41 5d 3d 3e 5b 43 5d | 20 76 69 61 20 42 2d 3e |[A]=>[C]| via B->|
|00000450| 0d 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |. | |
|00000460| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00000470| 20 20 20 20 20 20 20 41 | 52 50 20 72 65 71 75 65 | A|RP reque|
|00000480| 73 74 2c 20 74 61 72 67 | 65 74 20 43 2d 3e 0d 20 |st, targ|et C->. |
|00000490| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000004a0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000004b0| 20 20 20 20 20 20 20 20 | 20 3c 2d 20 41 52 50 20 | | <- ARP |
|000004c0| 72 65 70 6c 79 20 66 72 | 6f 6d 20 43 2d 42 0d 20 |reply fr|om C-B. |
|000004d0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000004e0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|000004f0| 20 20 20 20 20 49 50 20 | 5b 41 5d 3d 3e 5b 43 5d | IP |[A]=>[C]|
|00000500| 20 2d 3e 0d 20 20 20 20 | 20 20 20 20 20 20 20 20 | ->. | |
|00000510| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 | | |
|00000520| 20 20 20 20 20 20 20 20 | 20 20 20 3c 2d 20 41 52 | | <- AR|
|00000530| 50 20 72 65 71 75 65 73 | 74 2c 20 74 61 72 67 65 |P reques|t, targe|
|00000540| 74 20 41 0d 20 0d 20 0d | 49 46 20 6e 6f 20 70 61 |t A. . .|IF no pa|
|00000550| 74 68 20 65 78 69 73 74 | 73 20 62 65 74 77 65 65 |th exist|s betwee|
|00000560| 6e 20 41 20 61 6e 64 20 | 43 20 74 68 69 73 20 69 |n A and |C this i|
|00000570| 73 20 74 68 65 20 65 6e | 64 20 6f 66 20 74 68 65 |s the en|d of the|
|00000580| 20 77 6f 72 6c 64 20 75 | 6e 6c 65 73 73 20 20 43 | world u|nless C|
|00000590| 0d 68 61 64 20 6d 61 6e | 75 61 6c 6c 79 20 61 64 |.had man|ually ad|
|000005a0| 64 65 64 20 61 20 72 6f | 75 74 65 20 73 61 79 69 |ded a ro|ute sayi|
|000005b0| 6e 67 20 74 68 61 74 20 | 74 72 61 66 66 69 63 20 |ng that |traffic |
|000005c0| 66 72 6f 6d 20 43 20 74 | 6f 20 41 20 67 6f 65 73 |from C t|o A goes|
|000005d0| 20 76 69 61 20 42 2e 0d | 20 0d 54 68 65 20 66 69 | via B..| .The fi|
|000005e0| 72 73 74 20 70 68 61 73 | 65 20 6f 66 20 72 6f 75 |rst phas|e of rou|
|000005f0| 74 69 6e 67 20 61 6e 73 | 77 65 72 73 20 74 68 69 |ting ans|wers thi|
|00000600| 73 20 70 72 6f 62 6c 65 | 6d 3a 2d 0d 20 0d 57 68 |s proble|m:-. .Wh|
|00000610| 65 6e 20 20 42 20 20 67 | 65 74 73 20 61 6e 20 49 |en B g|ets an I|
|00000620| 50 20 70 61 63 6b 65 74 | 20 74 6f 20 66 6f 72 77 |P packet| to forw|
|00000630| 61 72 64 2c 20 69 74 20 | 6e 6f 74 65 73 20 69 66 |ard, it |notes if|
|00000640| 20 69 74 20 69 73 20 62 | 65 69 6e 67 20 75 73 65 | it is b|eing use|
|00000650| 64 20 61 73 20 61 0d 72 | 6f 75 74 65 72 20 28 49 |d as a.r|outer (I|
|00000660| 53 29 20 61 6e 64 20 64 | 65 74 65 72 6d 69 6e 65 |S) and d|etermine|
|00000670| 73 20 77 68 65 74 68 65 | 72 20 74 68 65 20 6e 65 |s whethe|r the ne|
|00000680| 78 74 20 68 6f 70 20 69 | 73 20 74 68 65 20 6c 61 |xt hop i|s the la|
|00000690| 73 74 20 68 6f 70 20 20 | 69 6e 20 20 74 68 65 0d |st hop |in the.|
|000006a0| 72 6f 75 74 65 2e 20 20 | 20 54 68 69 73 20 20 69 |route. | This i|
|000006b0| 73 20 20 64 6f 6e 65 20 | 20 69 6e 20 69 70 72 6f |s done | in ipro|
|000006c0| 75 74 65 28 29 20 61 66 | 74 65 72 20 72 6f 75 74 |ute() af|ter rout|
|000006d0| 65 20 72 65 73 6f 6c 75 | 74 69 6f 6e 20 62 79 20 |e resolu|tion by |
|000006e0| 63 68 65 63 6b 69 6e 67 | 0d 69 70 2e 64 65 73 74 |checking|.ip.dest|
|000006f0| 20 61 67 61 69 6e 73 74 | 20 67 61 74 65 77 61 79 | against| gateway|
|00000700| 2e 20 20 49 66 20 74 68 | 65 20 74 77 6f 20 61 72 |. If th|e two ar|
|00000710| 65 20 74 68 65 20 73 61 | 6d 65 2c 20 74 68 69 73 |e the sa|me, this|
|00000720| 20 69 73 20 74 68 65 20 | 6c 61 73 74 20 68 6f 70 | is the |last hop|
|00000730| 2e 0d 57 65 27 72 65 20 | 61 20 67 61 74 65 77 61 |..We're |a gatewa|
|00000740| 79 20 69 66 20 69 70 2e | 73 72 63 20 69 73 20 6e |y if ip.|src is n|
|00000750| 6f 74 20 6f 75 72 20 6f | 77 6e 20 49 50 20 61 64 |ot our o|wn IP ad|
|00000760| 64 72 65 73 73 2e 0d 20 | 0d 49 66 20 20 74 68 65 |dress.. |.If the|
|00000770| 73 65 20 63 6f 6e 64 69 | 74 69 6f 6e 73 20 61 72 |se condi|tions ar|
|00000780| 65 20 6d 65 74 2c 20 69 | 70 5f 72 6f 75 74 65 28 |e met, i|p_route(|
|00000790| 29 20 63 61 6c 6c 73 20 | 61 20 72 6f 75 74 69 6e |) calls |a routin|
|000007a0| 65 20 74 6f 20 65 6e 61 | 62 6c 65 20 49 53 2d 45 |e to ena|ble IS-E|
|000007b0| 53 0d 72 6f 75 74 69 6e | 67 20 66 72 6f 6d 20 74 |S.routin|g from t|
|000007c0| 68 65 20 73 6f 75 72 63 | 65 20 49 50 20 61 64 64 |he sourc|e IP add|
|000007d0| 72 65 73 73 20 74 6f 20 | 74 68 65 20 64 65 73 74 |ress to |the dest|
|000007e0| 69 6e 61 74 69 6f 6e 2e | 0d 20 0d 54 68 65 20 70 |ination.|. .The p|
|000007f0| 61 63 6b 65 74 20 69 73 | 20 66 6f 72 77 61 72 64 |acket is| forward|
|00000800| 65 64 20 6e 6f 72 6d 61 | 6c 6c 79 20 62 75 74 20 |ed norma|lly but |
|00000810| 77 68 65 6e 20 43 20 69 | 73 73 75 65 73 20 20 61 |when C i|ssues a|
|00000820| 6e 20 20 41 52 50 20 20 | 72 65 71 75 65 73 74 20 |n ARP |request |
|00000830| 20 74 6f 0d 72 65 73 6f | 6c 76 65 20 77 68 65 72 | to.reso|lve wher|
|00000840| 65 20 20 41 20 20 69 73 | 2c 20 20 42 20 20 77 69 |e A is|, B wi|
|00000850| 6c 6c 20 20 72 65 73 70 | 6f 6e 64 20 20 6f 6e 20 |ll resp|ond on |
|00000860| 20 62 65 68 61 6c 66 20 | 20 6f 6e 20 20 41 2e 20 | behalf | on A. |
|00000870| 20 54 68 69 73 20 63 61 | 6e 20 62 65 0d 63 6f 6e | This ca|n be.con|
|00000880| 73 69 64 65 72 65 64 20 | 61 20 6c 69 6d 69 74 65 |sidered |a limite|
|00000890| 64 20 66 6f 72 6d 20 6f | 66 20 70 72 6f 78 79 20 |d form o|f proxy |
|000008a0| 41 52 50 2e 20 20 42 20 | 77 69 6c 6c 20 6f 6e 6c |ARP. B |will onl|
|000008b0| 79 20 72 65 73 70 6f 6e | 64 20 74 6f 20 20 61 6e |y respon|d to an|
|000008c0| 20 20 41 52 50 0d 72 65 | 71 75 65 73 74 2c 20 74 | ARP.re|quest, t|
|000008d0| 61 72 67 65 74 20 41 2c | 20 66 72 6f 6d 20 43 20 |arget A,| from C |
|000008e0| 61 6e 64 20 6f 6e 6c 79 | 20 43 2e 0d 20 0d 43 20 |and only| C.. .C |
|000008f0| 20 77 69 6c 6c 20 20 6e | 6f 77 20 20 70 61 73 73 | will n|ow pass|
|00000900| 20 20 49 50 20 70 61 63 | 6b 65 74 73 20 74 6f 20 | IP pac|kets to |
|00000910| 42 20 77 68 69 63 68 20 | 77 69 6c 6c 20 67 65 74 |B which |will get|
|00000920| 20 66 6f 72 77 61 72 64 | 65 64 20 74 6f 20 41 20 | forward|ed to A |
|00000930| 69 6e 20 74 68 65 0d 6e | 6f 72 6d 61 6c 20 77 61 |in the.n|ormal wa|
|00000940| 79 2e 20 20 57 65 20 6e | 6f 77 20 68 61 76 65 20 |y. We n|ow have |
|00000950| 61 20 72 6f 75 74 65 20 | 66 72 6f 6d 20 41 20 74 |a route |from A t|
|00000960| 6f 20 43 20 61 6e 64 20 | 68 61 76 65 20 65 73 74 |o C and |have est|
|00000970| 61 62 6c 69 73 68 65 64 | 20 61 20 20 77 61 79 0d |ablished| a way.|
|00000980| 66 6f 72 20 43 20 74 6f | 20 67 65 74 20 62 61 63 |for C to| get bac|
|00000990| 6b 20 74 6f 20 41 2e 0d | 20 0d 42 20 20 68 61 73 |k to A..| .B has|
|000009a0| 20 20 61 20 20 74 61 62 | 6c 65 20 6f 66 20 77 68 | a tab|le of wh|
|000009b0| 69 63 68 20 49 50 20 61 | 64 64 72 65 73 73 65 73 |ich IP a|ddresses|
|000009c0| 20 69 74 20 73 68 6f 75 | 6c 64 20 72 65 73 70 6f | it shou|ld respo|
|000009d0| 6e 64 20 74 6f 20 41 52 | 50 20 72 65 71 75 65 73 |nd to AR|P reques|
|000009e0| 74 73 0d 61 6e 64 20 74 | 6f 20 77 68 6f 6d 20 69 |ts.and t|o whom i|
|000009f0| 74 20 73 68 6f 75 6c 64 | 20 72 65 73 70 6f 6e 64 |t should| respond|
|00000a00| 2e 20 20 54 61 62 6c 65 | 20 65 6e 74 72 69 65 73 |. Table| entries|
|00000a10| 20 61 72 65 20 20 61 67 | 65 64 20 20 61 6e 64 20 | are ag|ed and |
|00000a20| 20 75 6c 74 69 6d 61 74 | 65 6c 79 0d 64 72 6f 70 | ultimat|ely.drop|
|00000a30| 70 65 64 20 6f 6e 20 61 | 20 74 69 6d 65 20 70 65 |ped on a| time pe|
|00000a40| 72 69 6f 64 20 73 69 6d | 69 6c 61 72 20 74 6f 20 |riod sim|ilar to |
|00000a50| 6e 6f 72 6d 61 6c 20 41 | 52 50 20 65 6e 74 72 69 |normal A|RP entri|
|00000a60| 65 73 2e 0d 20 0d 20 0d | 54 68 69 73 20 63 61 70 |es.. . .|This cap|
|00000a70| 61 62 69 6c 69 74 79 20 | 69 73 20 69 6d 70 6c 65 |ability |is imple|
|00000a80| 6d 65 6e 74 65 64 20 76 | 69 61 20 74 68 65 20 69 |mented v|ia the i|
|00000a90| 73 5f 65 73 20 63 6f 6d | 6d 61 6e 64 2e 20 20 54 |s_es com|mand. T|
|00000aa0| 68 69 73 20 66 75 6e 63 | 74 69 6f 6e 20 77 61 73 |his func|tion was|
|00000ab0| 0d 66 69 72 73 74 20 64 | 65 76 65 6c 6f 70 65 64 |.first d|eveloped|
|00000ac0| 20 62 79 20 53 74 75 20 | 50 68 69 6c 6c 69 70 73 | by Stu |Phillips|
|00000ad0| 2c 20 4e 36 54 54 4f 20 | 66 6f 72 20 4e 4f 53 20 |, N6TTO |for NOS |
|00000ae0| 61 6e 64 20 77 61 73 20 | 70 6f 72 74 65 64 20 20 |and was |ported |
|00000af0| 77 69 74 68 20 20 68 69 | 73 0d 70 65 72 6d 69 73 |with hi|s.permis|
|00000b00| 73 69 6f 6e 20 74 6f 20 | 20 4e 45 54 2f 4d 61 63 |sion to | NET/Mac|
|00000b10| 2e 20 20 20 20 49 27 76 | 65 20 20 69 6d 70 6c 65 |. I'v|e imple|
|00000b20| 6d 65 6e 74 65 64 20 20 | 74 68 65 20 61 62 6f 76 |mented |the abov|
|00000b30| 65 20 61 6e 64 20 68 65 | 72 65 20 61 72 65 20 74 |e and he|re are t|
|00000b40| 68 65 0d 72 65 73 75 6c | 74 73 20 6f 66 20 69 6e |he.resul|ts of in|
|00000b50| 69 74 69 61 6c 20 74 65 | 73 74 69 6e 67 3a 2d 0d |itial te|sting:-.|
|00000b60| 0d 31 2e 20 49 74 20 77 | 6f 72 6b 73 20 6a 75 73 |.1. It w|orks jus|
|00000b70| 74 20 66 69 6e 65 20 73 | 75 62 6a 65 63 74 20 74 |t fine s|ubject t|
|00000b80| 6f 20 2a 6f 6e 65 2a 20 | 70 72 6f 62 6c 65 6d 2e |o *one* |problem.|
|00000b90| 20 20 4f 6e 63 65 20 41 | 20 61 6e 64 20 43 20 61 | Once A| and C a|
|00000ba0| 72 65 20 69 6e 0d 20 20 | 20 63 6f 6d 6d 75 6e 69 |re in. | communi|
|00000bb0| 63 61 74 69 6f 6e 20 61 | 6e 64 20 74 68 65 20 63 |cation a|nd the c|
|00000bc0| 68 61 6e 6e 65 6c 20 67 | 65 74 73 20 63 6f 6e 67 |hannel g|ets cong|
|00000bd0| 65 73 74 65 64 2c 20 54 | 43 50 20 63 6f 6e 6e 65 |ested, T|CP conne|
|00000be0| 63 74 69 6f 6e 73 20 72 | 75 6e 6e 69 6e 67 0d 20 |ctions r|unning. |
|00000bf0| 20 20 6f 76 65 72 20 74 | 68 65 20 72 6f 75 74 65 | over t|he route|
|00000c00| 20 62 65 67 69 6e 20 74 | 6f 20 62 61 63 6b 2d 6f | begin t|o back-o|
|00000c10| 66 66 20 61 73 20 6e 6f | 72 6d 61 6c 2e 20 20 20 |ff as no|rmal. |
|00000c20| 20 49 66 20 20 74 68 65 | 20 20 63 68 61 6e 6e 65 | If the| channe|
|00000c30| 6c 20 20 67 65 74 73 0d | 72 65 61 6c 6c 79 20 63 |l gets.|really c|
|00000c40| 6f 6e 67 65 73 74 65 64 | 2c 20 20 20 69 74 20 20 |ongested|, it |
|00000c50| 69 73 20 70 6f 73 73 69 | 62 6c 65 20 74 68 61 74 |is possi|ble that|
|00000c60| 20 74 68 65 20 62 61 63 | 6b 2d 6f 66 66 20 70 65 | the bac|k-off pe|
|00000c70| 72 69 6f 64 20 67 65 74 | 73 20 6c 6f 6e 67 65 72 |riod get|s longer|
|00000c80| 0d 74 68 61 6e 20 74 68 | 65 20 6c 69 66 65 20 6f |.than th|e life o|
|00000c90| 66 20 74 68 65 20 49 53 | 2d 45 53 20 72 6f 75 74 |f the IS|-ES rout|
|00000ca0| 69 6e 67 20 74 61 62 6c | 65 20 65 6e 74 72 79 20 |ing tabl|e entry |
|00000cb0| 61 74 20 42 20 61 6e 64 | 20 6c 6f 6e 67 65 72 20 |at B and| longer |
|00000cc0| 74 68 61 6e 20 20 41 52 | 50 0d 74 61 62 6c 65 20 |than AR|P.table |
|00000cd0| 65 6e 74 72 79 20 66 6f | 72 20 20 41 20 20 61 74 |entry fo|r A at|
|00000ce0| 20 43 2e 20 20 53 6f 20 | 77 68 65 6e 20 74 68 65 | C. So |when the|
|00000cf0| 20 54 43 50 20 72 65 74 | 72 79 20 74 69 6d 65 72 | TCP ret|ry timer|
|00000d00| 20 63 6f 6d 70 6c 65 74 | 65 73 2c 20 43 20 77 69 | complet|es, C wi|
|00000d10| 6c 6c 0d 41 52 50 20 66 | 6f 72 20 41 20 62 75 74 |ll.ARP f|or A but|
|00000d20| 20 42 20 77 69 6c 6c 20 | 6e 6f 20 6c 6f 6e 67 65 | B will |no longe|
|00000d30| 72 20 72 65 73 70 6f 6e | 64 2e 20 20 54 68 65 20 |r respon|d. The |
|00000d40| 63 6f 6e 6e 65 63 74 69 | 6f 6e 20 69 73 20 6e 6f |connecti|on is no|
|00000d50| 77 20 68 75 6e 67 20 6a | 75 73 74 0d 61 73 20 20 |w hung j|ust.as |
|00000d60| 69 66 20 20 41 20 61 6e | 64 20 43 20 77 65 72 65 |if A an|d C were|
|00000d70| 20 69 6e 20 64 69 72 65 | 63 74 20 63 6f 6d 6d 75 | in dire|ct commu|
|00000d80| 6e 69 63 61 74 69 6f 6e | 20 61 6e 64 20 41 20 73 |nication| and A s|
|00000d90| 69 6d 70 6c 79 20 77 65 | 6e 74 20 61 77 61 79 20 |imply we|nt away |
|00000da0| 28 65 67 3a 0d 70 6f 77 | 65 72 27 64 20 6f 66 66 |(eg:.pow|er'd off|
|00000db0| 29 2e 20 20 54 68 65 20 | 20 73 6f 6c 75 74 69 6f |). The | solutio|
|00000dc0| 6e 20 20 74 6f 20 20 74 | 68 69 73 20 69 73 20 66 |n to t|his is f|
|00000dd0| 75 6c 6c 20 72 6f 75 74 | 69 6e 67 3b 20 69 6e 20 |ull rout|ing; in |
|00000de0| 74 68 65 20 20 6d 65 61 | 6e 74 69 6d 65 0d 74 68 |the mea|ntime.th|
|00000df0| 65 20 20 66 75 6e 63 74 | 69 6f 6e 20 20 73 74 69 |e funct|ion sti|
|00000e00| 6c 6c 20 20 73 65 72 76 | 65 73 20 20 61 20 75 73 |ll serv|es a us|
|00000e10| 65 66 75 6c 20 70 75 72 | 70 6f 73 65 20 69 6e 20 |eful pur|pose in |
|00000e20| 65 6e 61 62 6c 69 6e 67 | 20 63 6f 6d 6d 75 6e 69 |enabling| communi|
|00000e30| 63 61 74 69 6f 6e 0d 62 | 65 74 77 65 65 6e 20 6e |cation.b|etween n|
|00000e40| 6f 64 65 73 2e 0d 20 0d | 32 2e 20 52 6f 75 6e 64 |odes.. .|2. Round|
|00000e50| 2d 74 72 69 70 20 74 69 | 6d 65 73 20 61 72 65 20 |-trip ti|mes are |
|00000e60| 63 6c 65 61 72 6c 79 20 | 67 6f 69 6e 67 20 74 6f |clearly |going to|
|00000e70| 20 62 65 20 6c 6f 6e 67 | 65 72 20 74 68 61 6e 20 | be long|er than |
|00000e80| 66 6f 72 20 64 69 72 65 | 63 74 20 20 6e 6f 64 65 |for dire|ct node|
|00000e90| 0d 74 6f 20 6e 6f 64 65 | 20 63 6f 6e 6e 65 63 74 |.to node| connect|
|00000ea0| 69 6f 6e 73 2e 20 20 20 | 54 68 69 73 20 20 65 78 |ions. |This ex|
|00000eb0| 61 63 65 72 62 61 74 65 | 73 20 20 20 20 74 68 65 |acerbate|s the|
|00000ec0| 20 20 20 54 43 50 20 20 | 62 61 63 6b 2d 6f 66 66 | TCP |back-off|
|00000ed0| 20 20 70 72 6f 62 6c 65 | 6d 0d 64 65 73 63 72 69 | proble|m.descri|
|00000ee0| 62 65 64 20 61 62 6f 76 | 65 2e 0d 00 00 00 00 00 |bed abov|e.......|
|00000ef0| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000f00| 00 00 01 00 00 00 01 00 | 00 00 00 00 00 00 00 1e |........|........|
|00000f10| 01 81 98 00 00 00 00 e0 | 37 ff ff 00 01 85 9c 00 |........|7.......|
|00000f20| 00 00 00 e0 38 ff ff 00 | 01 89 a0 00 00 00 00 e0 |....8...|........|
|00000f30| 1b 69 73 5f 65 73 20 43 | 6f 6d 6d 61 6e 64 20 44 |.is_es C|ommand D|
|00000f40| 6f 63 75 6d 65 6e 74 61 | 74 69 6f 6e 02 00 00 00 |ocumenta|tion....|
|00000f50| 00 00 50 61 72 74 53 49 | 54 21 00 00 00 00 00 00 |..PartSI|T!......|
|00000f60| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000f70| 00 00 aa c6 21 b3 00 00 | 00 00 00 00 01 1e bc 00 |....!...|........|
|00000f80| 00 00 00 e0 40 ff ff 00 | 01 a9 c0 00 00 00 00 e0 |....@...|........|
|00000f90| 41 ff ff 00 01 ad c4 00 | 00 00 00 e0 42 ff ff 00 |A.......|....B...|
|00000fa0| 01 af 94 00 00 00 00 e0 | 43 ff ff 00 01 b1 bc 00 |........|C.......|
|00000fb0| 00 00 00 e0 44 ff ff 00 | 01 b2 9c 00 00 00 00 e0 |....D...|........|
|00000fc0| 45 ff ff 00 01 b6 a0 00 | 00 00 00 e0 46 ff ff 00 |E.......|....F...|
|00000fd0| 01 ba a4 00 00 00 00 e0 | 47 ff ff 00 01 be a8 00 |........|G.......|
|00000fe0| 00 00 00 e0 48 ff ff 00 | 01 c2 ac 00 00 00 00 e0 |....H...|........|
|00000ff0| 49 ff ff 00 01 c6 b0 00 | 00 00 00 e0 4a ff ff 00 |I.......|....J...|
|00001000| 00 00 01 00 00 00 01 00 | 00 00 00 00 00 00 00 1e |........|........|
|00001010| 00 00 00 00 00 00 00 00 | 00 1c 00 1e ff ff 00 00 |........|........|
|00001020| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00001030| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00001040| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00001050| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00001060| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00001070| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
+--------+-------------------------+-------------------------+--------+--------+