tailieunhanh - The Illustrated Network- P11

The Illustrated Network- P11:In this chapter, you will learn about the protocol stack used on the global public Internet and how these protocols have been evolving in today’s world. We’ll review some key basic defi nitions and see the network used to illustrate all of the examples in this book, as well as the packet content, the role that hosts and routers play on the network, and how graphic user and command line interfaces (GUI and CLI, respectively) both are used to interact with devices. | 69 QUESTIONS FOR READERS Figure shows some of the concepts discussed in this chapter and can be used to help you answer the following questions. Client Server VLAN 1 Server Client VLAN 2 Broadcast messages sent only to the VLAN 1 broadcast domain and router . Broadcast messages sent only to the VLAN 2 broadcast domain and router . Hub LAN Switch FIGURE Hubs bridges and routers can connect LAN segments to form an internetwork. 1. What is the main function of the ARP message on a LAN 2. What is the difference between TCP and UDP terms of connection overhead and reliability 3. What is a transparent bridge 4. What is the difference between a bridge and a router in terms of broadcast domains 5. What is the relationship between a broadcast domain and a VLAN CHAPTER Network Link Technologies 3 What You Will Learn In this chapter you will learn more about the links used to connect the nodes of the Illustrated Network. We ll investigate the frame types used in various technologies and how they carry packets. We ll take a long look at Ethernet and mention many other link types used primarily in private networks. You will learn about SONET SDH DSL and wireless technologies as well as Ethernet. All four link types are used on the Illustrated Network. This chapter explores the physical and data link layer technologies used in the Illustrated Network. We investigate the methods used to link hosts and intermediate nodes together over shorter LAN distances and longer WAN distances to make a complete network. For most of the rest of the book we ll deal with packets and their contents. This is our only chance to take a detailed look at the frames employed on our network and even peer inside them. Because the Illustrated Network is a real network we ll emphasize the link types used on the network and take a more cursory look at link types that might be very important in the TCP IP protocol suite but are not used on our network. We ll look at Ethernet and the Synchronous .