《计算机网络与因特网》求取 ⇩

Chapter 1 Introduction1

1．1 Growth Of Computer Networking1

1．1 Growth Of Computer Networking1

Chapter Contents1

1．2 Complexity in Network Systems2

1．3 Mastering The Complexity2

1．3 Mastering The Complexity2

1．2 Complexity In Network Systems2

1．4 Concepts And Terminology3

1．5 Organization Of The Text3

1．5 Organization Of The Text3

1．4 Concepts And Terminology3

1．6 Summary4

1．6 Summary4

7．8 An Example Frame Format7

2．2 Copper Wires7

2．1 Introduction7

Chapter 2 Transmission Media7

PART 1 Data Transmission7

2．3 Glass Fibers9

2．4 Radio10

2．5 Microwave10

2．8 Summary12

2．7 Laser12

2．6 Infrared12

3．1 Introduction15

Chapter 3 Local Asynchronous Communication (RS-232)15

3．3 Using Electric Current To Send Bits16

3．2 The Need For Asynchronous Communication16

3．5 Asynchronous Character Transmission With RS-23217

3．4 Standards For Communication17

3．6 Baud Rate, Framing , And Errors19

3．7 Full Duplex Asynchronous Communication20

3．9 Hardware Bandwidth And The Transmission Of Bits21

3．8 Limitations Of Real Hardware21

3．10 Summary22

Chapter 4 Long-Distance Communication (Carriers And Modems)25

4．1 Introduction25

4．2 Sending Signals Across Long Distances25

4．3 Modem Hardware Used For Modulation And Demodulation28

4．5 Optical, Radio,And Dialup Modems29

4．4 Leased Serial Data Circuits29

4．6 Carrier Frequencies And Multiplexing31

4．8 Summary33

4．7 Time Division Multiplexing33

PARTⅡ Packet Transmission37

Chapter 5 Packets, Frames, And Error Detection37

5．1 Introduction37

5．2 The Concept Of Packets37

5．3 Packets And Time-Division Multiplexing39

5．4 Packets And Hardware Frames40

5．5 Byte Stuffing41

5．6 Transmission Errors43

5．7 Parity Bits And Parity Checking43

5．8 Probability,Mathematics,And Error Detection44

5．9 Detecting Errors With Checksums45

5．10 Detecting Errors With Cyclic Redundancy Checks46

5．11 Combining Building Blocks47

5．13 Summary49

5．12 Frame Format And Error Detection Mechanisms49

6．2 Direct Point-to-Point Communication53

Chapter 6 LAN Technologies And Network Topology53

6．1 Introduction53

6．3 Shared Communication Channels55

6．4 Significance Of LANs And locality Of Reference56

6．5 LAN Topologies57

6．6 Example Bus Network : Ethernet59

6．7 Carrier Sense On Multi-Access Networks(CSMA)60

6．8 Collision Detection And Backoff(CSMA/CD)61

6．9 Another Example Bus Network :LocalTalk62

6．10 Example Ring Network :IBM Token Ring63

6．11 Another Example Ring Network :FDDI64

6．12 Example Star Network :ATM66

6．13 Summary67

7．1 Introduction71

Chapter 7 Hardware Addressing And Frame Type Identification71

7．3 How LAN Hardware Uses Addresses To Filter Packets72

7．2 Specifying A Recipient72

7．4 Format Of A Physical Address74

7．5 Broadcasting And A Broadcast Address75

7．7 Frame Headers And Frame Format76

7．6 Identifying Packet Contents76

7．9 Using Networks That Do Not Have Self-identifying Frames78

7．10 Network Analyzers, Physical Addresses,Frame Types80

7．11 Summary82

7．12 Ethernet Address Assignment83

8．2 Speeds Of LANs And Computers85

Chapter 8 LAN Wiring , Physical Topology , And Interface Hardware85

8．1 Introduction85

8．3 Network Interface Hardware86

8．4 The Connection Between A NIC And A Network88

8．5 Original Thick Ethernet Wiring88

8．6 Connection Multiplexing90

8．7 Thin Ethernet Wiring91

8．8 Twisted Pair Ethernet92

8．9 Advantages And Disadvantages Of Wiring Schemes94

8．11 Network Interface Cards And Wiring Schemes96

8．10 The Topology Paradox96

8．12 Wiring Schemes And Other Network Technologies98

8．13 Summary99

9．2 Distance Limitation And LAN Design101

9．1 Introduction101

Chapter 9 Extending LANs : Fiber Modems, Repeaters,Bridges ,and Switches 101101

9．3 Fiber Optic Extensions102

9．4 Repeaters103

9．5 Bridges106

9．6 Frame Filtering107

9．8 Planning A Bridged Network108

9．7 Startup And Steady State Behavior of Bridged Networks108

9．9 Bridging Between Buildings109

9．10 Bridging Across Longer Distances110

9．11 A Cycle Of Bridges112

9．12 Distributed Spanning Tree113

9．13 Switching113

9．14 Combining Switches And Hubs114

9．16 Summary115

9．15 Bridging And Switching With Other Technologies115

Chapter 10 WAN Technologies And Routing119

10．1 Introduction119

10．2 Large Networks And Wide Areas119

10．3 Packet Switches120

10．4 Forming A WAN121

10．5 Store And Forward122

10．6 Physical Addressing In A WAN123

10．7 Next-Hop Forwarding123

10．8 Source Independence125

10．9 Relationship Of Hierarchical Addresses To Routing125

10．10 Routing In A WAN126

10．11 Use Of Default Routes128

10．13 Shortest Path Computation In A Graph129

10．12 Routing Table Computation129

10．15 Vector Distance Routing132

10．14 Distributed Route Computation132

10．17 Example WAN Technologies134

10．16 Link-State Routing(SPF )134

10．18 Summary137

Chapter 11 Network Ownership, Service Paradlgm, And Performance141

11．1 Introduction141

11．2 Network Ownership142

11．3 Service Paradigm143

11．4 Connection Duration And Persistence144

11．5 Examples of Service Paradigms146

11．6 Addresses And Connection Identifiers147

11．7 Network Performance Characteristics148

11．8 Summary151

12．2 The Need For Protocols155

12．1 Introduction155

Chapter 12 Protocois And Layering155

12．3 Protocol Suites156

12．5 The Seven Layers157

12．4 A Plan For Protocol Design157

12．6 Stacks : Layered Software159

12．7 How Layered Software Works160

12．9 The Scientific Basis For Layering161

12．8 Multiple,Nested Headers161

12．10 Techniques Protocols Use162

12．11 The Art Of Protocol Design170

12．12 Summary171

PARTⅢ Internetworking175

13．2 The Motivation For Internetworking175

13．1 Introduction175

Chapter 13 Internetworking : Concepts, Architecture,and Protocols175

13．4 Universal Service In A Heterogeneous World176

13．3 The Concept Of Universal Service176

13．6 Physical Network Connection With Routers177

13．5 Internetworking177

13．7 Internet Architecture178

13．8 Achieving Universal Service179

13．9 A Virtual Network179

13．11 Significance Of Internetworking And TCP/IP181

13．10 Protocols For Internetworking181

13．12 Layering And TCP/IP Protocols182

13．13 Host Computers, Routers, And Protocol Layers183

13．14 Summary184

14．2 Addresses For The Virtual Internet187

Chapter 14 IP : Internet Protocol Addresses187

14．1 Introduction187

14．3 The IP Addressing Scheme188

14．4 The IP Address Hierarchy189

14．5 Classes Of IP Addresses189

14．6 Computing The Class of An Address191

14．7 Dotted Decimal Notation192

14．8 Classes And Dotted Decimal Notation192

14．9 Division Of The Address Space193

14．11 An Addressing Example194

14．10 Authority For Addresses194

14．12 Special IP Addresses195

14．13 Summary Of Special IP Addresses197

14．15 Routers And The IP Addressing Principle198

14．14 The Berkeley Broadcast Address Form198

14．16 Multi-Homed Hosts199

14．17 Summary200

15．1 Introduction203

Chapter 15 Binding Protocol Addresses(ARP)203

15．2 Protocol Addresses And Packet Delivery204

15．3 Address Resolution204

15．4 Address Resolution Techniques205

15．5 Address Resolution With Table Lookup206

15．6 Address Resolution With Closed-Form Computation207

15．7 Address Resolution With Message Exchange208

15．8 Address Resolution Protocol209

15．9 ARP Message Delivery210

15．10 ARP Message Format211

15．11 Sending An ARP Message212

15．12 Identifying ARP Frames213

15．14 Processing An Incoming ARP Message213

15．13 Caching ARP Responses213

15．15 Layering, Address Resolution,Protocol Addresses214

15．16 Summary215

16．1 Introduction219

16．2 Connectionless Service219

Chapter 16 IP Datagrams And Datagram Forwarding219

16．3 Virtual Packets220

16．4 The IP Datagram221

16．5 Forwarding An IP Datagram222

16．6 IP Addresses And Routing Table Entries223

16．8 Destination And Next-Hop Addresses224

16．7 The Mask Field And Datagram Forwarding224

16．9 Best-Effort Delivery225

16．10 The IP Datagram Header Format226

16．11 Summary227

Chapter 17 IP Encapsulation,Fragmentation,And Reassembly229

17．2 Datagram Transmission And Frames229

17．1 Introduction229

17．3 Encapsulation230

17．4Transmission Across An Internet231

17．5 MTU,Datagram Size, And Encapsulation232

17．6 Reassembly234

17．7 Identifying A Datagram234

17．9 Fragmenting A Fragment235

17．8 Fragment Loss235

17．10 Summary236

18．2 The Success Of IP239

18．1 Introduction239

Chapter 18 The Future IP(Ipv6)239

18．3 The Mot?vation For Change240

18．4 A Name And A Version Number241

18．5 Characterization Of Features In Ipv6241

18．6 IPv6 Datagram Format242

18．7 IPv6 Base Header Format242

18．8 How IPv6 Handles Multiple Headers244

18．9 Fragmentation, Reassembly,And Path MTU245

18．10 The Purpose Of Multiple Headers246

18．11 IPv6 Addressing247

18．13 Summary248

18．12 IPv6 Colon Hexadecimal Notation248

Chapter 19 An Error Reporting Mechanism(ICMP)251

19．1 Introduction251

19．2 Best-Effort Semantics And Error Detection251

19．3 Internet Control Message Protocol252

19．4 ICMP Message Transport254

19．6 Using ICMP To Trace A Route255

19．5 Using ICMP Messages To Test Reachability255

19．7 Using ICMP For Path MTU Discovery256

19．8 Summary257

20．2 The Need For Reliable Transport259

20．1 Introduction259

Chapter 20 TCP : Reliable Transport Service259

20．3 The Transmission Control Protocol260

20．4 The Service TCP Provides To Applications260

20．5 End-To-End Service And Datagrams261

20．6 Achieving Reliability262

20．7 Packet Loss And Retransmission263

20．8 Adaptive Retransmission264

20．10 Buffers．Flow Control,And Windows265

20．9 Compar?son Of Retransmission Times265

20．11 Three-Way Handshake267

20．12 Congestion Control268

20．13 TCP Segment Format268

20．14 Summary269

Chapter 21 Client-Server interaction273

PART Ⅳ Network Applications273

21．1 Introduction273

21．2 The Functionality Application Software Provides274

21．3 The Functionality An Internet Provides274

21．4 Making Contact275

21．5 The Client-Server Paradigm275

21．6 Characteristics Of Clients And Servers275

21．8 Requests, Responses,And Direction Of Data Flow276

21．7 Server Programs And Server-Class Computers276

21．9 Transport Protocols and Client-Server Interaction277

21．10 Multiple Services On One Computer278

21．11 Identifying A Particular Service279

21．12 Multiple Copies of A Server For A Single Service279

21．13 Dynamic Server Creation280

21．14 Transport Protocols And Unambiguous Communication280

21．15 Connection-Oriented And Connectionless Transport281

21．16 A Service Reachable Through Multiple Protocols282

21．17 Complex Client-Server Interactions282

21．18 Interactions And Circular Dependencies283

21．19 Summary283

22．2 Application Program Interface285

22．1 Introduction285

Chapter 22 The Socket Interface285

22．3 The Socket API286

22．4 Sockets And Socket Libraries286

22．5 Socket Communication And UNIX I/O287

22．6 Sockets, Descriptors, And Network I/O288

22．7 Parameters And The Socket API288

22．8 Procedures That Implement The Socket API289

22．9 Read And Write With Sockets295

22．10 Other Socket Procedures295

22．11 Sockets,Threads,And Inheritance296

22．12 Summary296

23．2 Connection-Oriented Communication299

23．1 Introduction299

Chapter 23 Example Of A Client And A Server299

23．5 Sequence Of Socket Procedure Calls300

23．4 Command-Line Arguments For The Example Programs300

23．3 An Example Service300

23．6 Code For Example Client302

23．7 Code For Example Server305

23．8 Stream Service And Multiple Recv Calls307

23．9 Socket Procedures And Blocking308

23．10 Size Of The Code And Error Reporting308

23．11 Using The Example Client With Another Service309

23．12 Using Another Client To Test The Server309

23．13 Summary310

24．1 Introduction313

Chapter 24 Naming With The Domain Name System313

24．2 Structure Of Computer Names314

24．3 Geographic Structure315

24．4 Domain Names Within An Organization316

24．5 The DNS Client-Server Model318

24．6 The DNS Server Hierarchy318

24．8 Locality Of Reference And Multiple Servers320

24．7 Server Architectures320

24．10 Resolving A Name321

24．9 Links Among Servers321

24．12 Types Of DNS Entries323

24．11 Optimization Of DNS Performance323

24．13 Aliases Using The CNAME Type324

24．14 An Important Consequence Of Multiple Types324

24．16 Summary325

24．15 Abbreviations And The DNS325

25．2 The Electronic Mail Paradigm329

25．1 Introduction329

Chapter 25 Eiectronic Mail Representation And Transfer329

25．3 Electronic Mailboxes And Addresses330

25．4 Electronic Mail Message Format331

25．5 Carbon Copies333

25．6 Multipurpose Internet Mail Extensions333

25．8 Mail Transfer335

25．7 E-mail And Application Programs335

25．9 The Simple Mail Transfer Protocol336

25．10 Optimizing For Multiple Recipients On A Computer336

25．11 Mail Exploders, Lists ,And Forwarders336

25．12 Mail Gateways337

25．13 Automated Mailing Lists338

25．14 Mail R?lays And E-mail Addresses339

25．15 Mailbox Access340

25．16 Dialup Connections And POP342

25．17 Summary342

Chapter 26 File Transfer And Remote File Access345

26．1 Introduction345

26．2 Data Transfer And Distributed Computation345

26．4 Generalized File Transfer346

26．3 Saving Intermediate Results346

26．5 Interactive And Batch Transfer Paradigms347

26．7 FTP General Model And User Interface348

26．6 The File Transfer Protocol348

26．8 FTP Commands349

26．9 Connections , Authorization, And File Permissions350

26．11File Transfer In Either Direction351

26．10 Anonymous File Access351

26．14 Changing Directories And Listing Contents352

26．12Wildcard Expansion In File Names352

26．13 File Name Translation352

26．15 File Types And Transfer Modes353

26．16 Example Of Using FTP354

26．18 Client-Server Interaction In FTP356

26．17 Verbose Output356

26．19 Control And Data Connections356

26．20 Data Connections And End Of File357

26．22 Network File System358

26．21 Trivial File Transfer Protocol358

26．23 Summary359

27．2 Browser interface363

Chapter 27 World Wide Web Pages And Browsing363

27．1 Introduction363

27．3 Hypertext And Hypermedia364

27．4 Document Representation364

27．5 HTML Format And Representation365

27．7 Headings367

27．6 Example HTML Formatting Tags367

27．9 Embedding Graphics Images in A Web Page368

27．8 Lists368

27．10 Identifying A Page369

27．11 Hypertext Links From One Document To Another370

27．12 Client-Server Interaction371

27．13 Web Document Transport And HTTP372

27．14 Browser Architecture372

27．15 Optional Clients373

27．16 Caching In Web Browsers374

27．27 Summary375

Chapter 28 CGI Technology For Dynamic Web Documents379

28．1 Introduction379

28．2 Three Basic Types of Web Documents380

28．3 Advantages And Disadvantages Of Each Document Type380

28．4 Implementation Of Dynamic Documents382

28．5 The CGI Standard383

28．6 Output From A CGI Program383

28．7 An Example CGI Program384

28．8 Parameters And Environment Variables386

28．10 A CGI Script With Long-Term State Information387

28．9 State Information387

28．11 A CGI Script With Short-Term State Information389

28．12 Forms And Interaction392

28．13 Summary392

29．1 Introduction395

Chapter 29 Java Technology For Active Web Documents395

29．2 An Early Form of Continuous Update396

29．3 Active Documents And Server Overhead397

29．4 Active Document Representation And Translation397

29．5 Java Technology399

29．6 The Java Programming Language399

29．7 The Java Run-Time Environment401

29．8 The Java Library402

29．9 A Graphics Toolkit403

29．10 Using Java Graphics on A Particular Computer404

29．12 Compiling A Java Program405

29．11 Java Interpreters And Browsers405

29．13 An Example Applet406

29．14 Invoking An Applet408

29．15 Example Of Interaction With A Browser409

29．16 Errors And Exception Handling411

29．17 Alternatives And Variations411

29．18 Summary412

Chapter 30 Network Management(SNMP)415

30．1 Introduction415

30．2 Managing An Internet415

30．3 The Danger Of Hidden Failures416

30．4 Network Management Software417

30．5 Clients, Servers, Managers,And Agents417

30．6 Simple Network Management Protocol418

30．7 Fetch-Store Paradigm418

30．8 The MIB And Object Names419

30．10 MIB Variables That Correspond To Arrays420

30．9 The Variety Of MIB Variables420

30．11 Summary421

31．2 Secure Networks And Policies423

Chapter 31 Network Security423

31．1 Introductionk423

31．3 Aspects Of Security424

31．5 Integrity Mechanisms425

31．4 Responsibility And Control425

31．7 Encryption And Privacy426

31．6 Access Control And Passwords426

31．9 Authentication With Digital Signatures427

31．8 Public Key Encryption427

31．10 Packet Filtering428

31．11 Internet Firewall Concept430

31．12 Summary431

Chapter 32 Initialization (Configuration)433

32．2 Bootstrapping433

32．1 Introduction433

32．3 Starting Protocol Software434

32．4 Protocol Parameters434

32．6 Examples Of Items That Need To Be Configured435

32．5 Protocol Configuration435

32．7 Example Configuration : Using A Disk File436

32．8 The Need To Automate Protocol Configuration437

32．9 Methods For Automated Protocol Configuration437

32．10 The Address Used To Find An Address438

32．11 A Sequence Of Protocols Used During Bootstrap439

32．12 Bootstrap Protocol(BOOTP)439

32．13 Automatic Address Assignment441

32．15 Optimizations In DHCP442

32．14 Dynamic Host Configuration Protocol(DHCP)442

32．16 DHCP Message Format443

32．18 Summary444

32．17 DHCP And Domain Names444

Appendix 1 Glossary Of Networking Terms And Abbreviations447

Appendix 2 The ASCII Character Set477

Appendix3 How To Use The CD-ROM Included With This Book479

Bibliography485

Index495