Chapter 6
6.1 Network Layer Protocols
1. The network layer uses four basic processes. These are:
2. There are several network layer protocols in existence; however, only the following two are commonly implemented. These are:
3. List and explain the basic characteristics of IP.
4. There is one major characteristic of the media that the network layer considers. This is:
5. What is fragmenting the packet or fragmentation?
6. Mark the following IP characteristics as either:
a. Connectionlessb. Best Effort c. Media Independent.
______Will send a packet even if the destination host is not able to receive it.
______Does not guarantee that the packet will be delivered fully without errors.
______Will adjust the size of the packet sent depending on what type of network access will be used.
______Packet delivery is not guaranteed.
______Fiber optics cabling, satellites, and wireless can all be used to route the same packet.
______No contact is made with the destination host before sending a packet.
7. An IPv4 packet has two parts. These are:
8. The fields used to identify and validate a packet, or reorder a fragmented packet include:
9. Why would a router have to fragment a packet?
10. Draw a line between the IPv4 header function and the correct category.
VersionIdentifies the IP address of the recipient host
Total LengthIdentifies the number of 32-bit words in the header
Time-to-LiveAlways set to 0100 for IPv4
ProtocolIdentifies the IP address of the sending host
Internet Header LengthIdentifies the upper-layer protocol; to be used next
Destination IP AddressMaximum value is 65,535 bytes
Differentiated ServicesCommonly referred to as hop count
Header ChecksumIdentifies the priority for each packet
Source IP AddressSe utiliza para controlar errores del encabezado del paquete.
11. List and explain the three major issues IPv4 has.
12. List four improvements that IPv6 provides.
13. How many addresses does IPv6 provide?
14. The IPv6 simplified header offers several advantages over IPv4. These include:
15. The fields in the IPv6 header include:
16. Draw a line between the IPV6 header description and the IPV6 header field to which it belongs.
Traffic ClassIs always set to 0110
Hop LimitIdentifies the packet fragment size
Next HeaderWhen this value reaches 0, the sender is notified that the packet was not delivered
VersionClassifies packets for congestion control
Flow LabelIdentifies the application type to the upper-layer protocol
Payload LengthCan be set to use the same pathway flow so that packets are not reordered upon delivery
6.2 Routing
17. Another role of the network layer is to direct packets between hosts. A host can send a packet to:
18. The router connected to the local network segment is referred to as the __________.
19. What is the purpose of a default gateway?
20. Explain what a routing table is.
21. The routing table of a local host typically contains what information?
22. The default gateway is only used when a host must forward packets to a remote network. When is a default gateway not required, or needed to be configured?
23. What commands on a Windows host can be used to display the host routing table?
24. List and explain what the routing table of a router stores information about.
26. What does a local host require to send packets to a remote destination?
27. What command is used on a Cisco IOS router to display the routing table information?
28. What does each circled part of the routing table below tell the network administrator?
______
______
C192.168.10.0/24 is directly connected, GigabitEthernet0/0
L192.168.10.1/32 is directly connected, GigabitEthernet0/0
C220.200.20.0/24 is directly connected, GigabitEthernet0/1
______
29. Explain what the following letters in the routing table represent?
a. ____C____ -
b. ____L____ -
c. ____S____ -
d. ____D____ -
e. ____O____ -
30. Which metric has the highest priority; 2170112 or 1?
32. If a router receives a packet to a destination network that is not in the routing table and no default gateway is available, what happens to the packet?
33.
Based on the graphic assign the correct letter to each statement.
______Shows the destination network.
______The administrative distance (source) and metric to reach the remote network.
______How the network was learned by the router.
______The outgoing interface on the router to reach the destination network.
______The elapsed time since the network was discovered.
______The next hop IP address to reach the remote network.
6.3 Routers
34. All router models are essentially computers. Just like computers, tablets, and smart devices, routers also require:
35. A router also has special memory that includes:
36. A router has access to four types of memory. Explain each.
37. The connections on a Cisco router can be grouped into two categories. List and explain each.
38. Similar to a Cisco switch, there are several ways to access the CLI environment on a Cisco router. List and explain the most common methods.
39. Router interfaces can be grouped into two categories. List and explain both.
40. Draw a line between the router component name and the correct function/description.
WAN interfaceA way to remotely access the CLI across a network interface.
Aux portConnects computers, switches, and routers for internal networking.
LAN interfaceA port to manage routers – using telephone lines and modems.
Telnet or SSHConnects routers to external networks, usually over a large distance.
Console portA local port which uses USB or low-speed, serial connections to manage network devices.
41. Where is the Cisco IOS stored?
42. During boot up the Cisco IOS is copied into?
43. Which two files are loaded when a router is booted?
44. There are three major phases to the bootup process. These are:
45. Whatcommand can be used to verify and troubleshoot some of the basic hardware and software components of the router?
46. The output from the show version command includes:
47. The configuration register has several uses, such as:
48. The factory default setting for the configuration register is 0x2102. What does this value mean?
49. List the four steps to the router boot process in correct order.
6.4 Configuring a Cisco Router
50. What are the recommended stepsthat should be completed when configuring initial settings on a router?
51. What steps are required to activate a router interface?
52. There are several commands that can be used to verify interface configuration. Which is the most useful of these is thecommands?
53. What are three other commands that can be used to verify interface configuration?
54. For an end device to communicate over the network, it must be configured with the correct IP address information, including the default gateway address. When is the default gateway used?
55. Where is the default gateway generally located?
56. What is the command used to configure the default gateway 10.250.1.1 on a switch?
57. A common misconception is that the switch uses its configured default gateway address to determine where to forward packets originating from hosts connected to the switch and destined for hosts on a remote network. What does the switch use its default gateway for?