This chapter identifies the characteristics and functions of network devices. In an ideal world, this project would require hands-on experience with these devices, but this is not an ideal world, and access to this equipment is not always easy. Therefore, we will include two exercises that you might be required to perform if such devices are used on your network.
This project assumes that you are using Windows 2000.
One of the tools network administrators have at their disposal is the tracert utility. tracert allows you to see the hops a network packet takes to get to its destination. At each point along the way, the packet gives information about the route it is taking, along with details of the routers it crosses. More information on the tracert utility is provided in Chapter 13, “Troubleshooting Connectivity.”
NOTE
Firewalls If you are using a system that is protected by a firewall system, this exercise might not work because firewalls are commonly configured to block tracert traffic.
In this exercise, you will use the tracert utility to view the path to an Internet destination. This project assumes that you are using Windows 2000.
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Open a command window by selecting Start, Run. In the command box, type cmd.exe and then click OK. |
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1: | You have configured a 100Mbps network connection between your computer and the switch as half-duplex. What will be the maximum speed of the connection?
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A1: | b. A half-duplex connection operates at the normal speed of the link. Thus, a 100Mbps network connection in a half-duplex configuration would operate at a maximum of 100Mbps. All the other answers are invalid. For more information, see the section “Working with Hubs and Switches,” in this chapter. |
2: | You want to create a larger network by connecting two switches together. One of the switches has a port that can be switched from MDI to MDI-X as needed. The other switch doesn't have such a port or a dedicated uplink port. Which type of cable should you use, and how should you configure the switchable port to create the larger network?
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A2: | b. Because one of the switches does not have MDI capability, the switchable port should be set to MDI-X. Then, a crossover cable should be used to cancel out the crossing between the two devices. None of the other options would result in a successful connection. For more information, see the section “Working with Hubs and Switches,” in this chapter. |
3: | Of the following, which represents a valid MAC address?
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A3: | a. A MAC address comprises 6 bytes presented in a hexadecimal format. The letters A through F and numbers 0 through 9 are the only valid characters. Therefore, all the other answers provided are incorrect. For more information, see the section “Identifying MAC Addresses,” in this chapter. |
4: | A bridge makes forwarding decisions based on what information?
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A4: | b. Bridges make forwarding decisions based on the destination MAC address embedded in each packet. Routers use software addresses, such as IP addresses, to make forwarding decisions. Answers c and d are not valid. For more information, see the section “Bridges,” in this chapter. |
5: | What information does a switch use to determine the port to which data should be sent?
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A5: | c. A switch uses the MAC address of the connected device to determine the port to which data is forwarded. Routers use software addresses, such as IP addresses, to make forwarding decisions. Answer b is not valid. Although there are many addressing schemes used on networks, Ethernet address is not a valid term. Therefore, Answer d is incorrect. For more information, see the section “Switches,” in this chapter. |
6: | Which of the following is a link-state routing protocol used on TCP/IP networks?
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A6: | c. OSPF is a link-state routing protocol used on TCP/IP networks. RIP is a distance-vector routing protocol used on both TCP/IP and IPX/SPX networks, ARP is a component of the TCP/IP protocol suite. NLSP is a link-state routing protocol used on IPX/SPX networks. For more information, see the section “Routers,” in this chapter. |
7: | On a Windows 2000 system, what command would you use to view the MAC address?
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A7: | b. The ipconfig /all command shows a range of network-related information, including the MAC addresses of any installed NICs. None of the other answers are valid. For more information, see the section “Identifying MAC Addresses,” in this chapter. |
8: | What is the purpose of the uplink port on a hub or switch?
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A8: | b. The uplink port can be used to connect hubs and switches together, using a standard twisted-pair cable. All the other answers are invalid. For more information, see the section “Working with Hubs and Switches,” in this chapter. |
9: | By what method does a router determine the destination address for a packet?
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A9: | c. Routers use the software-configured network address to make routing decisions. Bridges use MAC addresses to make decisions. Answer d is not valid. The FCS (that is, frame checksum) field is used for error detection. For more information, see the section “Routers,” in this chapter. |
10: | Which of the following statements best describes split horizon?
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A10: | c. Split horizon is a routing algorithm which dictates that routes are not advertised back on the interface from which they were learned. Answer a describes the operation of the split horizon with poison reverse algorithm. None of the other answers are valid. For more information, see the section “Routers,” in this chapter. |
11: | In a network that uses distance-vector routing protocols, what information is included in the update that is sent out by each router?
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A11: | c. In a network that uses distance-vector routing protocols, routers advertise details of the routers they know about. These updates are sent to all the neighbor routers. Answer a describes the actions on a link-state-based network. Answers b and d are invalid. For more information, see the section “Routers,” in this chapter. |
12: | What is the difference between an active hub and a passive hub?
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A12: | d. An active hub regenerates the data signal before forwarding it to all connected devices. Active hubs come in both managed and unmanaged varieties. Answer b describes the action of a switch. Answer c is invalid. For more information, see the section “Hubs,” in this chapter. |
13: | What condition can arise if routers advertise a route back to the router from which it was learned?
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A13: | a. A count to infinity occurs when two routers provide information on the same destination and so create a routing loop. All the other answers are invalid. For more information, see the section “Routers” in this chapter. |
14: | What term is used by routers to describe each step necessary to reach a destination?
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A14: | a. Each step in the path between a router and its destination is called a hop. The other terms are not used in networking. For more information, see the section “Routers,” in this chapter. |
15: | What is the maximum speed of a 16550 UART chip?
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A15: | b. A 16550 UART chip is capable of speeds up to 115,200bps. None of the other answers are valid. For more information, see the section “Modems,” in this chapter. |
16: | What is the name of the bridging method used to segregate Ethernet networks?
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A16: | d. The bridging method used on Ethernet networks is called transparent because the other network devices are unaware of the existence of the bridge. Source-route bridges are used on Token Ring networks, invisible is not a type of bridge, and cut-through is a switching method, not a type of bridge. For more information, see the section “Bridges,” in this chapter. |
17: | Which of the following is a distance-vector routing protocol used on TCP/IP networks?
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A17: | d. RIP is a distance-vector routing protocol used on TCP/IP networks. ARP is a component of the TCP/IP protocol suite. NLSP is a link-state routing protocol used on IPX networks, and OSPF is a link-state routing protocol used on TCP/IP networks. For more information, see the section “Routers,” in this chapter. |
18: | A CSU/DSU is used in which of the following network configurations?
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A18: | c. CSUs/DSUs are used to convert the digital signals used on a LAN to the digital signals used on a WAN. The process described in Answer a would be performed by a gateway, and the process described in Answer b would be performed by a modem. Answer d is not valid because WANs commonly use digital signals. For more information, see the section “CSU/DSU,” in this chapter. |
19: | A router makes its forwarding decisions based on which of the following information?
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A19: | a. Routers make routing decisions based on the software-configured network address, which is protocol dependent. There is no such thing as an ARP address. Answers c and d are invalid. For more information, see the section “Routers,” in this chapter. |
20: | You are tasked with upgrading a new NIC in the company file and print server. Which of the following should you determine before buying a replacement card? (Choose the three best answers.)
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A20: | a, b, c. You should verify bus compatibility, network compatibility, and hardware compatibility before you buy a new NIC. You do not typically need to concern yourself with cooling requirements of a component. For more information, see the section “Network Interface Cards (NICs),” in this chapter. |
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