網(wǎng)絡(luò)系統(tǒng)集成技術(shù)復(fù)習(xí)教材

網(wǎng)絡(luò)系統(tǒng)集成概述

相關(guān)知識(shí)回顧（1）1/10/20231計(jì)算機(jī)網(wǎng)絡(luò)分類（一）從網(wǎng)絡(luò)的交換功能分類電路交換報(bào)文交換分組交換混合交換1/10/20232計(jì)算機(jī)網(wǎng)絡(luò)分類（二）從網(wǎng)絡(luò)的作用范圍進(jìn)行分類廣域網(wǎng)WAN(WideAreaNetwork)局域網(wǎng)LAN(LocalAreaNetwork)

城域網(wǎng)MAN(MetropolitanAreaNetwork)接入網(wǎng)AN(AccessNetwork)

1/10/20233廣域網(wǎng)、城域網(wǎng)、接入網(wǎng)以及局域網(wǎng)的關(guān)系城域網(wǎng)城域網(wǎng)接入網(wǎng)接入網(wǎng)接入網(wǎng)接入網(wǎng)接入網(wǎng)接入網(wǎng)廣域網(wǎng)局域網(wǎng)局域網(wǎng)校園網(wǎng)企業(yè)網(wǎng)……1/10/20234電路交換的特點(diǎn)電路交換必定是面向連接的。電路交換的三個(gè)階段：建立連接通信釋放連接1/10/20235電路交換舉例A和B通話經(jīng)過四個(gè)交換機(jī)通話在A到B的連接上進(jìn)行((((交換機(jī)交換機(jī)交換機(jī)交換機(jī)用戶線用戶線中繼線中繼線BDCA1/10/20236電路交換傳送計(jì)算機(jī)數(shù)據(jù)效率低計(jì)算機(jī)數(shù)據(jù)具有突發(fā)性。這導(dǎo)致通信線路的利用率很低。1/10/20237報(bào)文分組交換的原理（一）在發(fā)送端，先把較長(zhǎng)的報(bào)文劃分成較短的、固定長(zhǎng)度的數(shù)據(jù)段。1101000110101010110101011100010011010010假定這個(gè)報(bào)文較長(zhǎng)不便于傳輸1/10/20238數(shù)據(jù)數(shù)據(jù)數(shù)據(jù)報(bào)文分組交換的原理（二）每一個(gè)數(shù)據(jù)段前面添加上首部構(gòu)成分組。首部首部首部分組

1分組

2分組

3請(qǐng)注意：現(xiàn)在左邊是“前面”1/10/20239分組交換的原理（三）分組交換網(wǎng)以“分組”作為數(shù)據(jù)傳輸單元。依次把各分組發(fā)送到接收端（假定接收端在左邊）。數(shù)據(jù)首部分組

1數(shù)據(jù)首部分組

2數(shù)據(jù)首部分組

31/10/202310分組首首部的的重要要性每一個(gè)個(gè)分組的的首部部都含含有地址等控制制信息息。分組交交換網(wǎng)網(wǎng)中的的結(jié)點(diǎn)點(diǎn)交換換機(jī)根根據(jù)收收到的的分組組的首首部中中的地址信信息，把分分組轉(zhuǎn)發(fā)到下一一個(gè)結(jié)結(jié)點(diǎn)交交換機(jī)機(jī)。用這樣樣的存儲(chǔ)轉(zhuǎn)轉(zhuǎn)發(fā)方式，，最后后分組組就能能到達(dá)達(dá)最終目目的地地。12/29/202211分組交交換的的原理理（四四）接收端端收到到分組組后剝剝?nèi)ナ资撞窟€還原成成報(bào)文文。數(shù)據(jù)據(jù)首部分組

1數(shù)據(jù)據(jù)首部分組

2數(shù)據(jù)據(jù)首部分組

3收到的的數(shù)據(jù)據(jù)12/29/202212數(shù)據(jù)據(jù)數(shù)據(jù)據(jù)數(shù)據(jù)據(jù)分組交換的的原理（五五）最后，在接接收端把收收到的數(shù)據(jù)據(jù)恢復(fù)成為原原來的報(bào)文文。這里我們假假定分組在在傳輸過程程中沒有出出現(xiàn)差錯(cuò)，，在轉(zhuǎn)發(fā)時(shí)時(shí)也沒有被被丟棄。報(bào)文110100011010101011010101110001001101001012/29/202213分組組交交換換網(wǎng)網(wǎng)的的示示意意圖圖H1A分組組交交換換網(wǎng)網(wǎng)BDECH5H6H4H2H3H1向H5發(fā)送送分分組組H2向H6發(fā)送送分分組組注意意分分組組路路徑徑的的變變化化！！結(jié)點(diǎn)點(diǎn)交交換換機(jī)機(jī)主機(jī)機(jī)12/29/202214分組組交交換換的的優(yōu)優(yōu)點(diǎn)點(diǎn)高效效動(dòng)態(tài)態(tài)分分配配傳傳輸輸帶帶寬寬，，對(duì)對(duì)通通信信鏈鏈路路是是逐逐段段占占用用。。靈活活以分分組組為為傳傳送送單單位位和和查查找找路路由由。。迅速不必先建立連連接就能向其其他主機(jī)發(fā)送送分組；充分分使用鏈路的的帶寬?？煽客晟频木W(wǎng)絡(luò)協(xié)協(xié)議；自適應(yīng)應(yīng)的路由選擇擇協(xié)議使網(wǎng)絡(luò)絡(luò)有很好的生生存性。12/29/202215分組交交換帶帶來的的問題題分組在在各結(jié)結(jié)點(diǎn)存存儲(chǔ)轉(zhuǎn)轉(zhuǎn)發(fā)時(shí)時(shí)需要要排隊(duì)，這就就會(huì)造造成一一定的的時(shí)延。分組必必須攜攜帶的的首部部（里里面有有必不不可少少的控控制信信息））也造造成了了一定定的開銷。12/29/202216三種交交換的的比較較P1P2P3P4P1P2P3P4P3P4報(bào)文報(bào)文報(bào)文ABCDABCDABCD報(bào)文交交換電路交交換分組交交換t連接建立數(shù)據(jù)傳送報(bào)文P2P1連接釋放12/29/202217五層協(xié)議的的體系結(jié)構(gòu)構(gòu)應(yīng)用層(applicationlayer)運(yùn)輸層(transportlayer)網(wǎng)絡(luò)層(networklayer)數(shù)據(jù)鏈路層層(datalinklayer)物理層(physicallayer)數(shù)據(jù)鏈路層層5應(yīng)用層4運(yùn)輸層3網(wǎng)絡(luò)層2數(shù)據(jù)鏈路層層1物理層12/29/202218計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2應(yīng)用進(jìn)程數(shù)數(shù)據(jù)先傳送送到應(yīng)用層層加上應(yīng)用層層首部，成成為應(yīng)用層層PDU12/29/202219計(jì)算機(jī)1向計(jì)算機(jī)機(jī)2發(fā)送數(shù)據(jù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2應(yīng)用層PDU再傳傳送到運(yùn)運(yùn)輸層加上運(yùn)輸輸層首部部，成為為運(yùn)輸層層報(bào)文12/29/202220計(jì)算機(jī)1向計(jì)算機(jī)機(jī)2發(fā)送數(shù)據(jù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2運(yùn)輸層報(bào)報(bào)文再傳傳送到網(wǎng)網(wǎng)絡(luò)層加上網(wǎng)絡(luò)絡(luò)層首部部，成為為IP數(shù)據(jù)據(jù)報(bào)（或或分組））12/29/202221計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2IP數(shù)據(jù)報(bào)報(bào)再傳送到數(shù)數(shù)據(jù)鏈路層加上鏈路層首首部和尾部，，成為數(shù)據(jù)鏈鏈路層幀12/29/202222計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2數(shù)據(jù)鏈路層幀幀再傳送到物物理層最下面的物理理層把比特流流傳送到物理理媒體12/29/202223計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)應(yīng)用層(applicationlayer)5432154321物理傳輸媒媒體計(jì)算機(jī)1AP2AP1電信號(hào)（或或光信號(hào)））在物理媒媒體中傳播播從發(fā)送端物物理層傳送送到接收端端物理層計(jì)算機(jī)212/29/202224計(jì)算算機(jī)機(jī)1向計(jì)計(jì)算算機(jī)機(jī)2發(fā)送送數(shù)數(shù)據(jù)據(jù)5432154321計(jì)算算機(jī)機(jī)1AP2AP1計(jì)算算機(jī)機(jī)2物理理層層接接收收到到比比特特流流，，上上交交給給數(shù)數(shù)據(jù)據(jù)鏈鏈路路層層12/29/202225計(jì)算機(jī)1向計(jì)算機(jī)機(jī)2發(fā)送數(shù)據(jù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2數(shù)據(jù)鏈路路層剝?nèi)ト撞坎亢蛶参膊咳〕鰯?shù)據(jù)據(jù)部分，，上交給給網(wǎng)絡(luò)層層12/29/202226計(jì)算機(jī)1向計(jì)算機(jī)機(jī)2發(fā)送數(shù)據(jù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2網(wǎng)絡(luò)層剝剝?nèi)ナ撞坎浚〕龀鰯?shù)據(jù)部部分上交給運(yùn)運(yùn)輸層12/29/202227計(jì)算機(jī)機(jī)1向計(jì)算算機(jī)2發(fā)送數(shù)數(shù)據(jù)5432154321計(jì)算機(jī)機(jī)1AP2AP1計(jì)算機(jī)機(jī)2運(yùn)輸層層剝?nèi)トナ撞坎?，取取出?shù)數(shù)據(jù)部部分上交給給應(yīng)用用層12/29/202228計(jì)算機(jī)機(jī)1向計(jì)算算機(jī)2發(fā)送數(shù)數(shù)據(jù)5432154321計(jì)算機(jī)機(jī)1AP2AP1計(jì)算機(jī)機(jī)2應(yīng)用層層剝?nèi)トナ撞坎浚∪〕鰬?yīng)應(yīng)用程程序數(shù)數(shù)據(jù)上交給給應(yīng)用用進(jìn)程程12/29/202229計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2我收到了AP1發(fā)來的應(yīng)用程序數(shù)數(shù)據(jù)！12/29/202230計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2應(yīng)用程程序數(shù)數(shù)據(jù)應(yīng)用層首部H510100110100101比比特流流110101110101注意觀察加加入或剝?nèi)トナ撞浚ㄎ参膊浚┑膶訉哟螒?yīng)用程程序數(shù)數(shù)據(jù)H5應(yīng)用程序數(shù)據(jù)H4H5應(yīng)用程序數(shù)據(jù)H3H4H5應(yīng)用程序數(shù)據(jù)H4運(yùn)輸層首部H3網(wǎng)絡(luò)層首部H2鏈路層首部T2鏈路層尾部12/29/202231計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)210100110100101比比特流流110101110101計(jì)算機(jī)2的的物理層收收到比特流后后交給數(shù)據(jù)鏈路路層H2T2H3H4H5應(yīng)用程序數(shù)據(jù)12/29/202232H3H4H5應(yīng)用程序數(shù)據(jù)計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2數(shù)據(jù)鏈路層剝剝?nèi)撞亢秃蛶膊亢蟀褞臄?shù)據(jù)部部分交給網(wǎng)絡(luò)絡(luò)層H2T2H3H4H5應(yīng)用程序數(shù)據(jù)12/29/202233H4H5應(yīng)用程序數(shù)據(jù)H3H4H5應(yīng)用程序數(shù)據(jù)計(jì)算機(jī)1向計(jì)算機(jī)2發(fā)送數(shù)據(jù)5432154321計(jì)算機(jī)1AP2AP1計(jì)算機(jī)2網(wǎng)絡(luò)層剝?nèi)シ址纸M首部后把分組的數(shù)據(jù)據(jù)部分交給運(yùn)運(yùn)輸層12/29/202234H5應(yīng)用程序數(shù)據(jù)H4H5應(yīng)用程序數(shù)據(jù)計(jì)算算機(jī)機(jī)1向計(jì)計(jì)算算機(jī)機(jī)2發(fā)送送數(shù)數(shù)據(jù)據(jù)5432154321計(jì)算算機(jī)機(jī)1AP2AP1計(jì)算算機(jī)機(jī)2運(yùn)輸輸層層剝剝?nèi)ト?bào)報(bào)文文首首部部后后把報(bào)報(bào)文文的的數(shù)數(shù)據(jù)據(jù)部部分分交交給給應(yīng)應(yīng)用用層層12/29/202235應(yīng)用用程程序序數(shù)數(shù)據(jù)據(jù)H5應(yīng)用用程程序序數(shù)數(shù)據(jù)據(jù)計(jì)算算機(jī)機(jī)1向計(jì)計(jì)算算機(jī)機(jī)2發(fā)送送數(shù)數(shù)據(jù)據(jù)5432154321計(jì)算機(jī)機(jī)1AP2AP1計(jì)算機(jī)機(jī)2應(yīng)用層層剝?nèi)ト?yīng)用用層PDU首首部部后把應(yīng)用用程序序數(shù)據(jù)據(jù)交給給應(yīng)用用進(jìn)程程12/29/202236計(jì)算機(jī)機(jī)1向計(jì)算算機(jī)2發(fā)送數(shù)數(shù)據(jù)5432154321計(jì)算機(jī)機(jī)1AP2AP1計(jì)算機(jī)機(jī)2我收到到了AP1發(fā)來的的應(yīng)用程程序數(shù)數(shù)據(jù)！！12/29/202237沙漏計(jì)時(shí)器器形狀的TCP/IP協(xié)議議族HTTPSMTPDNSRTPTCPUDPIP網(wǎng)際層網(wǎng)絡(luò)接口層層運(yùn)輸層應(yīng)用層………網(wǎng)絡(luò)接口1網(wǎng)絡(luò)接口2網(wǎng)絡(luò)接口3Everythingo