Packet Guide to Core Network Protocols

1. Networking Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
What Is a Model? 1
Why Use a Model? 3
OSI Model 4
OSI—Beyond the Layers 7
OSI/ITU-T Protocols 8
Introducing TCP/IP 8
TCP/IP and the RFCs 11
The Practical Side of TCP/IP 13
Encapsulation 14
Addressing 15
Equipment 15
Reading 17
Summary 17
Review Questions 18
Review Answers 18
Lab Exercises 19
Activity 1—Examining Encapsulation 19
Activity 2—Protocol Distribution 19
Activity 3—Developing a Protocol/Architecture 19
2. Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Remember the Models 22
Structure 23
Preamble 23
Source and Destination MAC Addresses 24
Control Field (Type) 24
Data Field 24
Frame Check Sequence 25

Ethernet Type II vs. 802.3 25
MAC Addresses—Another Look 27
Ethernet Operation 29
Shared Media 30
Physical Layer 32
Cabling 33
Encoding 37
10Base-T 37
100Base-T 38
1000Base-T 39
Other Types of Signaling 39
Link Pulse 39
Autonegotiation 40
Topologies 40
Final Thoughts on Ethernet 41
Reading 41
Summary 42
Review Questions 42
Review Answers 42
Lab Exercises 43
Activity 1—Basic Framing 43
Activity 2—Control Field Values 43
Activity 3—Addressing 44
Activity 4—Destination Addresses 44
Activity 5—Logical Link Control 44
3. Internet Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Protocol Description 45
Structure 46
Addressing 53
Sample Host Configuration 55
Operation 56
Digging a Little Deeper...What Addressing is Sufficient? 57
Security Warning 58
Organizations for Assigning Addresses and Names 58
Standards and RFCs 59
Summary 60
Review Questions 60
Review Answers 60
Lab Exercises 61
Activity 1—Determining IP Address Components 61
Activity 2—IP Packet Capture 61
Activity 3—Header Checksum 61