How to master the basic knowledge of network

Cisco Network Technology Institute project is a training project launched by Cisco worldwide, which is mainly aimed at junior network engineers and technicians.

"CCNAExploration: Basic Knowledge of Network", as the designated teaching material of Cisco Network Technology College, is suitable for readers preparing to take CCNA certification examination. In addition, the course CCNAExploration: Network Basis of Cisco Network Technology Institute is also suitable for all kinds of network technicians to read.

"CCNAExploration: Routing Protocols and Concepts" is a course of Cisco Network Technology College, which was written by Cisco lecturers, aiming to serve as a reference book for readers to read anytime and anywhere. Consolidate the course content and make full use of time. In addition, CCNA Exploration: Routing Protocols and Concepts, a course of Cisco Network Technology College, also includes the topics involved in ccn cending ccna examination. The arrangement of the course CCNAExploration: Routing Protocols and Concepts in Cisco Network Technology College helps readers to focus on important concepts and successfully complete the course. Objective: At the beginning of each chapter, summarize the core concepts of this chapter in the form of questions. Key terms: A list of network terms cited in this chapter is provided at the beginning of each chapter. Glossary: More than 250 brand-new terminology references. "Check your understanding" questions and answers: Use the questions at the end of each chapter to test your understanding. The answers in the appendix explain each question. Challenge questions and exercises: challenge yourself with complex questions similar to those in the CCNA exam. The answers in the appendix explain each question. [Edit this paragraph] Directory Chapter 65438 +0 Living in a network-centric world 1

Target 1. 1

1.2 Key terms 1

1.3 Communicate with each other in a network-centric world 2

1.3. 1 network supports our lifestyle 2.

1.3.2 Today's most commonly used communication tools 3

1.3.3 Network supports our learning style 3

1.3.4 Network supports our working mode 4

1.3.5 The way the network supports our entertainment 5

1.4 communication: an indispensable part of life 5

1.4. 1 What is communication 6?

1.4.2 communication quality 6

1.5 network is platform 6.

1.5. 1 Communication through the network 7

1.5.2 network element 7

1.5.3 converged network 9

1.6 Internet architecture 10

1.6. 1 network architecture 10

1.6.2 Network architecture with fault tolerance

1.6.3 Extensible network architecture 13

1.6.4 quality of service provided 13

1.6.5 providing network security 15

1.7 Network Trends 16

1.7. 1 What is its development direction? 16

1.7.2 Employment opportunities in the network industry 17

1.8 summary 17

1.9 experiment 18

1. 10 Check your understanding 18

1. 1 1 challenges and exercises 20

1. 12 knowledge development 20

Chapter II Network Communication 2 1

2. 1 target 2 1

2.2 Key terms 2 1

2.3 communication platform 22

2.3. 1 communication element 22

2.3.2 Send Message 23

2.3.3 Network components 23

2.3.4 Terminal equipment and its role in the network 24

2.3.5 Intermediate equipment and its role in the network 24

Network media 25

2.4 Local Area Network, Wide Area Network and Internet 26

2.4. 1 LAN 26

Wan 26

2.4.3 Internet: a network composed of multiple networks 26

2.4.4 Network Representation 27

2.5 Protocol 28

2.5. 1 communication management rules 28

Network protocol 29

2.5.3 Protocol Series and Industry Standards 29

2.5.4 Protocol Interaction 29

2.5.5 Technical independence agreement 30

2.6 Using Hierarchical Model 30

2. 6. 1 Advantages of using hierarchical model 30

2.6.2 Protocol and Reference Model 3 1

2.6.3 TCP/IP model 3 1

2.6.4 Communication Process 32

2.6.5 Protocol data units and encapsulation 32

2.6.6 Sending and receiving flow 33

On-site inspection model 33

2.6.8 Comparison between OSI model and TCP/IP model 34

2.7 network addressing 35

Addressing 35 in the +0 network

2.7.2 transmitting data to terminal equipment 35

2.7.3 Access to data through the Internet 35

2.7.4 Data Reaching the Right Application 36

2.8 Summary 37

2.9 Experiment 37

Check your understanding 37

Challenges, problems and practices 39

2. 12 knowledge development 39

Chapter 3 Application Layer Functions and Protocols 4 1

3. 1 objective 4 1

3.2 Key Terminology 4 1

3.3 Application: Interface between Networks 42

3.3. 1 OSI model and TCP/IP model 42

Application layer software 44

3.3.3 User applications, services and application layer protocols 45

3.3.4 Application layer protocol functions

3.4 Preparing Applications and Services 46

3.4. 1 client-server mode 46

Server 46

3.4.3 Application layer services and protocols 47

3.4.4 Peer-to-Peer Networks and Applications 48

3.5 Application layer protocols and services example 49

3.5. 1 DNS services and protocols 50

3.5.2 WWW service and HTTP 53

3.5.3 E-mail service and SMTP/POP protocol 54

3.5.4 E-mail server process -MTA and MDA 55

FTP 56

DHCP 57

3.5.7 File Access Service and SMB Protocol 58

P2P service and Gnutella protocol 59

3.5.9 Remote Login Services and Protocols 60

3.6 Summary 6 1

3.7 Experiment 6 1

3.8 Check your understanding 62

3.9 Challenges, problems and practices 63

3. 10 knowledge development 64

Chapter 4 OSI transport layer 65

4. 1

4.2 Key terms 65

4.3 the role of the transport layer 66

The use of the transport layer 66

4.3.2 Support for reliable communication 69

4.3.3 TCP and UDP 70

4.3.4 Port addressing 7 1

4.3.5 Subparagraph and reorganization: divide and conquer 74

4.4 TCP: Reliable Communication 75

Create a reliable session 75

4.4.2 TCP server process 76

4.4.3 Establishment and termination of TCP connection 76

4.4.4 three-way handshake 76

TCP session termination 78

TCP window confirmation 79

4.4.7 TCP retransmission 80

4.4.8 TCP congestion control: reduce the number of data segments that may be lost to at least 80.

4.5 UDP protocol: low overhead communication 8 1

4.5. 1 UDP: Comparison of low overhead and reliability 8 1

4.5.2 UDP datagram reassembly 82

4.5.3 UDP server processes and requests 82

4.5.4 UDP client process 82

4.6 Summary 83

4.7 Experiment 84

4.8 Check your understanding 84

4.9 Challenges, problems and practices 86

4. 10 knowledge expansion 86

Chapter 5 OSI network layer 87

5. 1 learning objectives 87

5.2 Key terms 87

5.3 IPv4 address 88

5.3. 1 network layer: host-to-host communication 88

5.3.2 IPv4: Network layer protocol example 90

5.3.3 IPv4 data packet: encapsulating transport layer PDU 92

5.3.4 IPv4 packet header 92

5.4 Network: Host Grouping 93

5.4. 1 Create a universal data packet 93

5.4.2 Why should hosts be divided into networks? 95

5.4.3 Separating the network from the network 97

5.5 Routing: How to Handle Packets 98

5.5. 1 equipment parameters: external communication of network 98 is supported.

5.5.2 IP packets: end-to-end transmission of data 98

Gateway: the exit of the network 99

5.5.4 Routing: The path to the network is 100.

5.5.5 Destination Network 102

5.5.6 Next hop: Where will the packet go next 103?

5.5.7 Packet forwarding: send the packet to the destination 103.

5.6 Routing Process: How to Learn Routing 104

5.6. 1 static route 104

5.6.2 Dynamic Routing 104

5.6.3 Routing Protocol 105

5.7 Summary 106

5.8 Testing 106

5.9 Check your understanding 107

5. 10 challenges, problems and practices

5. 1 1 knowledge development 109

Chapter 6 Network Addressing: IPv4 1 10

Learning objective 1 10

6.2 Key terms 1 10

6.3 IPv4 address 1 1 1

6.3. 1 IPv4 address analysis

6.3.2 Conversion between binary and decimal 1 12

6.3.3 Decimal to binary conversion 1 14

6.3.4 Addressing communication types: unicast, broadcast and multicast 1 18.

6.4 IPv4 addresses for different purposes 12 1

6.4.1different types of addresses within the IPv4 network 12 1.

6.4.2 Subnet Mask: Define the network and host parts of the address 122.

6.4.3 Public address and private address 123

6.4.4 Special unicast IPv4 address 124

6.4.5 Traditional IPv4 addressing 125

6.5 address allocation 127

6.5. 1 planning network address 127

6.5.2 Static and dynamic address of end-user equipment 128

6.5.3 Select the equipment address 129.

6.5.4 Internet Assigned Names Organization (IANA) 130

6.5.5 ISP 13 1

6.6 Calculation address 132

6.6. 1 Is this host on my network? 132

6.6.2 Calculate the network, host and broadcast address 133.

6.6.3 Basic subnet 135

6.6.4 Subnet division: divide the network into 138 suitable sizes.

6.6.5 Subdivision subnet 140

6.7 Testing Network Layer 145

6.7.1ping127.0.0.1:Test the local protocol family 146.

6.7.2 ping Gateway: Test the connectivity with the local network 146.

6.7.3 ping the remote host: test the connectivity with the remote network 146.

6.7.4 traceroute(tracert): test path 147.

6.7.5 ICMPv4: protocol supporting test and message 149.

6.7.6 Overview of IPv6150

6.8 Summary 15 1

6.9 Test 15 1

6. 10 Check your understanding 152

6. 1 1 Challenges and exercises 153

6. 12 knowledge development 153

Chapter 7 OSI data link layer 154

7. 1 learning objectives 154

7.2 Key terms 154

7.3 data link layer: access medium 155

7.3. 1 Support and connect the upper services 155.

7.3.2 Control transmission through local media 156

7.3.3 Creating a Framework 157

7.3.4 Connect the upper layer service to the medium 158.

Standard 159

7.4 MAC technology: put the data into the medium 159.

7.4.1* * MAC159 with media.

7.4.2 MAC 16 1 No * * media.

7.4.3 Logical topology and physical topology 16 1

7.5 MAC: addressing and data encapsulation in frame 163.

7.5. 1 data link layer protocol: frame 163

7.5.2 Packaging into frames: the role of frame header 164

7.5.3 Addressing: The destination of the frame is 164.

7.5.4 Packaging into frames: the function of frame ends 165

7.5.5 Data Link Layer Frame Example 165

7.6 Summary: Tracking data transmission through the Internet 169

7.7 Summary 172

7.8 Testing 173

7.9 Check your understanding 173

7. 10 challenges, problems and practices

7. 1 1 knowledge development 174

Chapter 8 OSI physical layer 176

8. 1 learning objectives 176

8.2 Key terms 176

8.3 Physical layer: communication signal 177

8.3. 1 using the physical layer 177

8.3.2 Physical layer operation 177

8.3.3 Physical layer standard 178

8.3.4 Basic Principles of Physical Layer 178

8.4 Physical layer signal and coding: indicator bit 179.

8.4. 1 media signal bit 179

8.4.2 Coding: bit packet 18 1.

8.4.3 Data transmission capacity 182

8.5 Physical Media: Connecting Communication 183

8.5. 1 physical media type 183

8.5.2 copper dielectric 184

8.5.3 optical fiber medium 187

8.5.4 Wireless Media 189

8.5.5 Media connector 190

8.6 Summary 19 1

8.7 Test 19 1

8.8 Check your understanding 192

8.9 Challenges, Problems and Practices 193

8. 10 knowledge development 194

Chapter 9 Ethernet 195

9. 1 learning objectives 195

9.2 Key terms 195

9.3 Overview of Ethernet 196

9.3. 1 Ethernet: standards and implementation 196

9.3.2 Ethernet: Layer 1 and Layer 2 196.

9.3.3 Logical link control: connect the upper layer 197.

9.3.4 MAC: Get the data sent to the media 197.

9.3.5 Physical layer implementation of Ethernet 198

9.4 Ethernet: communicate through LAN 198.

9.4. 1 Ethernet history 199

9.4.2 Traditional Ethernet 199

9.4.3 Current Ethernet 200

9.4.4 Develop to 1Gbit/s and above at the speed of 200.

9.5 Ethernet frame201

9.5. 1 frame: encapsulated data packet 20 1.

9.5.2 Ethernet MAC address 202

9.5.3 Hexadecimal Counting and Addressing 203

9.5.4 Address of another floor 205

9.5.5 Ethernet unicast, multicast and broadcast 205

9.6 Ethernet MAC 207

9.6. 1 MAC 207 in Ethernet

9. 6. 2 CSMA/ Cadmium: Process 207

9.6.3 Ethernet Timing 209

9.6.4 Frame Gap and Backoff 2 1 1

9.7 Ethernet physical layer 2 12

9. 7. 1 10 Mbit/s and 100 Mbit/s Ethernet 2 12

9.7.2 Gigabit Ethernet 2 13

9.7.3 Ethernet: Future Choice 2 14

9.8 hubs and switches 2 15

9.8. 1 traditional Ethernet: use hub 2 15.

9.8.2 Ethernet: Use switch 2 16.

9.8.3 Exchange: Selective Forwarding 2 17

9.9 Address Resolution Protocol (ARP) 2 19

9.9. 1 Resolve IPv4 address into MAC address 2 19.

9.9.2 Maintain Mapping Cache 220

9.9.3 Delete Address Mapping 222

9.9.4 ARP broadcast problem 223

9. 10 Summary 223

9. 1 1 test223

Check your understanding.

Challenges, problems and practices 225

9. 14 knowledge development 225

Chapter 10 Network Planning and Wiring 226

10. 1 learning objective 226

10.2 key terms 226

10.3 local area network: establishing physical connection 227

10. 3. 1 Select the correct LAN device 227

10.3.2 equipment selection coefficient 228

10.4 equipment interconnection 230

10.4. 1 LAN and WAN: connection 230

Local area network connection 234

10.4.3 WAN connection 237

10.5 Develop an addressing scheme 239

10.5. 1 How many hosts are there on the network? 240

10.5.2 How many networks are there? 240

10.5.3 network address design standard 24 1

10.6 Compute subnet 242

10.6. 1 calculation address: for example 1 242.

10.6.2 calculation address: Example 2 245

10.7 device interconnection 246

10.7. 1 device interface 246

10.7.2 device management connection 247

10.8 Summary 248

10.9 test 249

Check your understanding 249

10. 1 1 challenges and exercises 250

10. 12 knowledge development 252

Chapter 1 1 Configuring and Testing Network 253

1 1. 1 learning objective 253

1 1.2 key terms 253

1 1.3 configuring Cisco devices: IOS foundation 254

1 1

1 1.3.2 access method 254

1 1.3.3 archives 256

1 1.3.4 introduces CiscoIOS mode 257.

1 1.3.5 basic IOS command structure 259

Using CLI to help 260 1. 3. 6

1 1.3.7 IOS check command 264

1 1.3.8 IOS configuration mode 266

11.4 Basic configuration of Cisco IOS 266

1 1.4. 1 naming device 266

1 1.4.2 Restrict device access: configure password and slogan 268

1 1.4.3 management overview 27 1

1 1.4.4 Configure interface 274

1 1.5 Check connectivity 276

1 1.5. 1 authentication protocol series 276

1 1.5.2 test interface 277

1 1.5.3 testing the local network280

1 1.5.4 Test the connectivity between the gateway and the remote 28 1

1 1.5.5 Trace the command and interpret the result of the trace command 282.

1 1.6 monitoring and recording network 286

1 1.6. 1 network baseline 286

1 1.6.2 capturing and interpreting trace information 287

1 1.6.3 Understanding Nodes 288 on the Network

1 1.7 Summary 290

1 1.8 test291

1 1.9 Check your understanding 292

1 1. 10 challenges and exercises 293

11.11knowledge development 293