数据通信技术.pdf

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56.141?/?+?5?67/?7?/5+?567.89?/?7?/6+89?.:/?75?/6+89?.;a/?77第一章?数据通信概述?1.1?!#$%?&()?#$%*#$%?+#$%*,-.?/0?12#$%3?4?5?6789:?8;:?”?第一章?数据通信概述?7N2?wx7N?Ft?VWwx”?L?O?VW?*?(?W?W?a?2?_?C?flS?6?!?1.3?7NVW2?wx3?)?7N?EVWst?mfi?i?t?1.3.1?L47B2?XYv6fi?7NVWst?7N-.?5?6?!?E?E?E?F?y?pVW?LM4?VWst?VW|G?O=?)?VWst?)?3?h?)?.?7Nfl?#*?#?)?VWstV?)?7N?6?E?G?!?#O=List?)?)?$%?#?数据通信技术数据通信技术数据通信技术数据通信技术?!#$%&()*+?#,%&-()*+?.?#/%&?0?(1!?23?2345?6?2345?789:;?=;?A?!BC1.3.2?List?)?3?h?5?VW?G?!&#O=)?s?m?+?#*?4?s?7N?p?”2?p?VW?s?)?G?O=第一章?数据通信概述?5DEFGHI()*+JK)?5?G?$O=G3?C?r“?E?E?4?*?“?.?#?E?3?mh?4?fg?.?c#?,fgh?*?K?K?(?uG3?!?(!?%?Mm?s?8#:?E$?G?$O=数据通信技术数据通信技术数据通信技术数据通信技术?LMNO?)?5?VW?/0?p?VW?%?&fi?(?VW)*?0+),iVWst?-.h?)?/?cdu?st?0,st)?)?+?)1.3.3?L4?|2?XYv6fi?7NVWstL?)?.?y?3?1/2c6?G?!?#O=Listh34?)?*47B7NVW?fi)?Li?stj?6?5?)?.?6?4_?E3?6?E?”fg?6?O)?E7|VW?+?8?9?6?W?*?5?m?:?;,/0?)#?0)?3?j?st?7N2?,)?y?*-.?7NVW?#$%?“hiw0?VW6HJ1.4.2?HDLC?7NI?6HJ-?.?/?/?0?1?1?1?2?#4?hi?k?7NI?6HJ1.HDLC?#?-?/?3?“?C_?K?C_?7?6HJ3?6?C?/*3?C_?m?VWC?7N!?L?I?:u6?:u?_?QR?m?I?6?_?)#?iOPi4?_?2?I?V?h?4?VW?-?/?3?Om?i“?VWi?“i?(i?)i?_?L?M?H?7NI?6Z?_?)(i?2?h?+?O6?!#?PQ7NI?ZPQ7NI?Z?“C?iZ?t?G?*O=数据通信技术数据通信技术数据通信技术数据通信技术?Zmh?h?+?_?“?h&I?I?4?st?h?st?2?s?+?s?y?y?7NVW?m?_?MPQfi?7?st?e 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CHINAPAC-./?01?Y$=?,?Ly?flF?QG?$?,L$?,LUQR?,L?QR?,?,?_?Yq?U?fi?_?Y?&?_?Yq?=HI?Y?L?N?HI)$L?1?HILHM?HILI)#?HI?ZJ?q?Y?qx?HIC?$,L!KHILlV?L?,第三章?分组交换数据网?L?L?B?,?!?M?L%&NO?V?PQ?!?Yq6?RN?Z?RR?HI?3 数据通信技术数据通信技术数据通信技术数据通信技术?4.1?4.1.1?!?#$?%&?()*?+,-?./-01-?23?456789:;?3AB)*?CCDEFGHIJK?LMNO?PQ?RS/?TU?V?WXYZ?_6?9Oab?cde?fghiH?jkl?mnW?opqrstuvghwxynWz9|?I?8?9?9?MS?$?I?-?%-?,?x5678?=F?3AB?,.?fl?GHK?fl56789:;?,?W/?W01A?DEF?2_6COa3?Q?45?(6?78?c?se?ftugh?T?9V?:;!:?78O?WXT?O?78第四章?帧中继技术?4.2.2?Q?45?RS/&?&A./?&+,ATBCrRS/?JK?RS/&?C*?WD?EFRS/?-?&GHI?-/G?WXO?GHI?B?DH?I?H?D?JWXK?WXJWXK?KL?RS/?x?RS/?r?KL?*?A?A?KL?数据通信技术数据通信技术数据通信技术数据通信技术?4.2.3?WX?W?M?Nt?OW78?78?,?PQWOJW/RST?NLU?Ntx?tu?M?V?Mb?O?W?$WX3?XtuW/?78YZYZO?WXC?tu?MT?N.?78?Q?S/?_?T?ab?Q?r?c78?T?dr?e?fg?h?P?WXRSTh?&i?j?d,V?FWXYZk0?WXRSTT?fiu?lm?Ntn?“N?WXl?8第四章?帧中继技术?!rs“N?o?T?Q?78,?R?dlm?pq?W4.2.4?gh6?WXrs?x781?,3t?O?WX?:u?vwx?78?,?&?J?,?,?9?y?Q?i&?78?x?fiu4k?1yz?“N?WX4Q$?x?4,?i?4?i?&?|?G?v?y?O?4?NO?WX?4?!?l#?WXrs?tu?数据通信技术数据通信技术数据通信技术数据通信技术?4.2.5 PVC?-,Q?*WX?%?,?LM?WX*WX?-,LM,LM?*WXK?%?WX*WX?x?z?-?ojk?9f9?-?9?-?,LM?F?5?f?3?WXU?R?4.3?4.3.1?u?S?y?ghW?8?ghQ?%?WX?(?W9?W?W?W?9?GH?*?O?o?99m99“99*?9#GH?WfiflGH?r?9?GH?ghr?W?!gh?W?)*?h0?PT?fiflGHJKQ?)OW?WX?Wo?GHJKQ?“)O?W?WX?&?GHbJ?fiflGH?gh?“?W?WX?T?”?)O?W?WX?OW?9?!y?m?!y?r?gh?gh?W?(?87rghWw?O?9?1?WX,?1?GH?Q?I,?$?+?$?I?&?WOW?,&$?+?I?*?&?$?I?*OW?(#A?o?A?#?A?WX?rghW?&GH?F,?$?+?I?&?$?I&GH?&?$?I?0?$?gh,$?+?jk?gh?Q?w?&I?gh?J?&?第四章?帧中继技术?$?IK?./?4?gh?$?$?./?W?.?WX-?FWrgh?Oa?3?W&GH?$?gh?OW?$?”4.3.2?OW?tu?y?W?4?j?4?%?h?9?9/?*?4?-?9!?-?9?%?.?/09?,?*W?4?J9GH?W?1?jk23?r?OW?7,9WX?,9WXf3,9o,?O,?3O?OW?W/?9S/?W/R?3?l?,?&?,?$?+?A?r?GH?,?4.3.3?WX?gh?r?gho?gh?EFRS/gh?-?9?$?EFRS/gh?$?-?$?T?RS/gh?$?-?ghjk?$?%?9?$?ghz?-?9?$?W/z?9?LMJ?LM?9?LM?*KL?./LM?&?=tP?o?y4?pI?!*V?z%&?g“?z?#gJK9?gJK9?JlUJK?P?z?k!k0?4?N78?$?$?%&?2?(4 第五章 数字数据网（DDN）?5.1 DDN?5.1.1 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DDN?3?E?4+,?5?6?7?,?.?m?.?E?8?.9?F?O?2?%?,?数据通信技术数据通信技术数据通信技术数据通信技术?1.1234?;a:E?Eg;?/0?x#$:1?;/0?8?L?ABC?DEL?fi;DEW(?/0?DE1?FGH?%?bc?s8?W(?/0?#$?%?Q1?+34?.IJ?l?&?#K?B?k?a?C?L?deE?fi?,LM?U?/0.?/0?M/0?NOf?/0Q1?P?Q?P?/0?RJoS?/0?Q!?DEW(?/0Q1EW(?/0oO?/0?Q?C?fiTL?de?,a?US/0Q1?2.5234?;a:?/0?x#$?:?mEV?,?m?W?m?mEV?O;?E?(/0&?(/0?,?/0?&v?x/0?/0?3.67?m?N?XY?a:?,?m?.?#$?m?4.&8?#9:?!?/0?9?8?第五章 数字数据网（DDN）?/01?%?C?fiL?de?,?S?Q1?1?v?/0?x?/0?S:?9/0?/0Ov?/0?_?a!&!-f?!?5.3?DDN?(?,-?(7fl?&R/0?o“?F?O?%abcf?F?O?deRD?C?E!?*+?数据通信技术数据通信技术数据通信技术数据通信技术?&f?第五章 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第六章?计算机通信网?6.1?6.1.1?!?#?$?%&(?)*+?,-./0?12?3456789:;?A?BCD;?$EFG?H?IJKL?MN?OP?QR?ST?6?$EUVWXYAZ?V?$_?3a?$_?b?$_?VWXY?cdef?gQ?hiejfk?lmno?MNpqrs?t?uvw?$E?VWXY?vdxef?7yz?l|a?MNpqrs?#?)$E?VWXYd?ef?l?k?l?c?A?a?$?b?$?(?$?=?A?$?6.1.2?LAN?$_?%?n?XYo?MN?:;?MN?$?$?$?,?数据通信技术数据通信技术数据通信技术数据通信技术?1?pq?$?3(?3?pq?upqrs?$Epq?“?Q?fifl?fi?3?6?$E?,”?(rs?:;?($IJKL?$=?c0?K?pq?$=?W+?c?$E?fl?c?VW?c?k?fl?MNpq?s?NS?pq?(?s?v?6.1.3?$?v?V?AV?$V?3(?3?3?6?$?AV?$V?3?3$?3?3?67?$?pq?AV7V?$?$?$E?AV?$V?1?_?3?_?3?_?3_?!?$?第六章?计算机通信网?6.1.4?1.?IEEE802?#S9?fl?$?#?%?V?lV?t?OQR?ST?l?_$?)?=?#?%?V?#?%?$E)?#?$?)?S#$?%?/0?$?z?(?&?(?#?%?z?#(?/0_Q?&)*?$?z?/0+?H?)?$?=?/0?#?%?=?fl,?(?V?fl,?(-?./?0?k?y1A?fl2?3?4?5y1?!#(MN6?7?689:?$?z?#?$?z?OQR?ST?!#%?*?;?t?A?5MN?D?D?6?p?,?D?H?=?E?7A2MNIJ?G?3KL?fl3M:?NO?#?%?P,?$?z?$E?,?)?$?vKL?QeK?3?R?=?ST?UV/0?/1$E?/0?W?2$E?XY?Z?$?/0?W_?$?a?7$E?pq?$,?bcd?e?;?$o?ffA?MNpq/0?2.?g?#%?h?$?7?=ij-?5MN=?|V/06$?$E?/0?R?#?%?z?k?$S?MN?k?D?D?MNF?H?=D?B?v?$?=?P,?|?7te?|?MNFD?S?J?7?6H?=D?S?y1A6?YGp?n:?数据通信技术数据通信技术数据通信技术数据通信技术?$?=?flS?|V0?MN?fly1?&?(?MN?1M?1?KL?$E?S,?X?+?p(?MNUV?UVMN?X?+?(?7t:;?Yv?2?)?fl?$uv?fl?&?&?0?X?A?%?#?%?y?&?$?$?v?7?fl?6?QR?ST?*?&?!?+?&,?#$%&?()?R?*?(?A?.*(?&?G?6?*?&6?&?7?%?r?l?3?kS,?J?7?!?+%?n?”?I*(?/0?$?“1?S?$?fl?fl,C?v?p?6?VQR?R?*ST?&?#&?-*./?-*()?-?&?,?&?,?,&,?-*.?()?0$%123?0123?04536789?:;数据通信技术数据通信技术数据通信技术数据通信技术?6.2?I?$?XY,x?IJ1?R?|?IJKL?XY?&?l?$?|?$E?($E?l?0?UV?KLIJ?4?$?v!?$eKMN$?$?peKMN$?$?peKMN$?|?R?$?$eKMN$?lxVe?x?f?$?6.2.1?uI?$?(?$?S(?$?%$E?O?(?$E?fl?(?:;flW?(?$?l”YV?(?$EOP?l$.?/!?(?t?QR?%ST?R?$?)?3=?$=?)?3?$E?IJ?0(?!?!?#?#?$?#?#?=?AB第六章?计算机通信网?$?;l?0?t?/0Q?$?pq?S,6?B?7?.$?6?e#?6%?.$?2U.$?$?6?E)?$?Xp1B6?o?t$26?o?Z?$o$=?(?$E(?_gQ)&?$?dl60B?l)&?6?$?0?$?1l?$?ij3l$?7?YG?&6U?l$p%?l$?6.2.2?$?Q?p$?1?213(?QR?4 ST?C?DED?;l?$*?;?p?l1?V?UV$E?k.(?.k?(?UV?QR?ST?t?$?A?FGH?F?ABI)6.3?6.3.1?(Bridge)$?k?:;?X?$?z?MN=?(?t?,73p?/0?$?N?)?7k?2?#p?$E?$E?l$E?s?$X?MN?$EQ?3 53&#?#?3?#?.$?3$?35?(?Z$?;?V/0?S?0&?(?$E?A?(?$E?$?s0?$?(pq?$E?Zt?,KL?fl?b?0?$_?|?$?3?$?$?$E?t?l$E?第六章?计算机通信网?6.3.2?(Gateway)$?V?tX?$?z?$?A?$E?0?t0?(?a?A?V?MNe#V?/0?t_?(?Cq|?$E?6.3.3?(Router)=?X?$?z?$E?(?=?$,?0?FG?t?1l?$E?,$(?,$?l-.?$E?t2?l?)$?fl2?=?