Wendell odom

Chapter 2 
Fundamentals of Ethernet LANs 32
“Do I Know This Already?” Quiz 32
Foundation Topics 34
An Overview of LANs 34
Typical SOHO LANs 35
Typical Enterprise LANs 36
The Variety of Ethernet Physical Layer Standards 37
Consistent Behavior over All Links Using the Ethernet Data-Link 
Layer 38
Building Physical Ethernet LANs with UTP 39
Transmitting Data Using Twisted Pairs 39
Breaking Down a UTP Ethernet Link 40
UTP Cabling Pinouts for 10BASE-T and 100BASE-T 42
Straight-Through Cable Pinout 42
Choosing the Right Cable Pinouts 44
UTP Cabling Pinouts for 1000BASE-T 45
Building Physical Ethernet LANs with Fiber 46
Fiber Cabling Transmission Concepts 46
Using Fiber with Ethernet 48
Sending Data in Ethernet Networks 49
Ethernet Data-Link Protocols 49
Ethernet Addressing 50
Identifying Network Layer Protocols with the Ethernet Type 
Field 52
Error Detection with FCS 53
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Sending Ethernet Frames with Switches and Hubs 53
Sending in Modern Ethernet LANs Using Full Duplex 53
Using Half Duplex with LAN Hubs 54
Chapter Review 56
Chapter 3 
Fundamentals of WANs and IP Routing 58
“Do I Know This Already?” Quiz 58
Foundation Topics 60
Wide-Area Networks 60
Leased-Line WANs 61
Physical Details of Leased Lines 61
HDLC Data-Link Details of Leased Lines 63
How Routers Use a WAN Data Link 64
Ethernet as a WAN Technology 65
Ethernet WANs That Create a Layer 2 Service 66
How Routers Route IP Packets Using Ethernet Emulation 67
IP Routing 68
Network Layer Routing (Forwarding) Logic 68
Host Forwarding Logic: Send the Packet to the Default Router 69
R1 and R2’s Logic: Routing Data Across the Network 70
R3’s Logic: Delivering Data to the End Destination 70
How Network Layer Routing Uses LANs and WANs 70
How IP Addressing Helps IP Routing 72
Rules for Groups of IP Addresses (Networks and Subnets) 73
The IP Header 73
How IP Routing Protocols Help IP Routing 74
Other Network Layer Features 75
Using Names and the Domain Name System 76
The Address Resolution Protocol 77
ICMP Echo and the ping Command 78
Chapter Review 79