NET 102 - Networking Essentials II

Review for Second Test

The following questions are provided to help you study for the second test. Do not expect to see these exact questions on the test.

  1. What are the two protocols that the protocol suite that runs the Internet is named for?

  2. If a message is being passed from a host to a server, what is the order that message will follow through the OSI model's layers?

  3. There are about fourteen fields in an IPv4 packet header. What are the possible values in the version field? What is the largest value that can go in the Time to Live field? What does the number in the protocol field indicate?

  4. What is the most famous use of ICMP packets?

  5. What are the two main protocols of the OSI transport layer?

  6. What is the significance of ACK and NACK symbols with regard to TCP?

  7. Why do TCP packets need sequence numbers? (There are two reasons.)

  8. What command do you type on a Windows machine to view a machine's IP address? What is the command on a UNIX system?

  9. If we are using DHCP, what three values must be assigned to a device if DHCP is working properly?

  10. What are the three classful subnet masks, expressed in decimal notation?

  11. What is a class A subnet mask, expressed in binary notation?

  12. Convert the numbers 127 and 175 to binary notation.

  13. If we are using classful addresses, which byte of an IP address determines its class?

  14. What are the address ranges for the first four IP address classes?

  15. What is CIDR notation? How does it relate to subnet masking?

  16. What is the ARP protocol used for?

  17. Assume I am sending a message to a server on Amazon. What addresses go in the Network Layer header? What addresses go in the Data-Link layer header? Which header's addresses change when the message is processed by my gateway router?

  18. What are class D and E addresses used for?

  19. What is the class A private address range? What is the class B private address range? What is the class C private address range?

  20. If my network uses private addresses, how can I send a message across the Internet?

  21. What is subnetting? How do we accomplish it?

  22. If I need to create six subnets in a class C network, what will my new subnet mask look like?

  23. What is the formula for calculating the number of usable subnets we create? What is the formula for calculating the number of hosts we can have on each subnet?

  24. What is supernetting? How is it different from subnetting, in terms of what you must do?

  25. What is APIPA? What will an IP address look like if APIPA has been used? What standard setting will not be set if APIPA has been used?

  26. Assume you are at a Linux host, and want to release and renew its address for interface eth0. What commands will you give the machine?

  27. Why is a router not useful if it sits on only one network?

  28. Must a router hand off all frames it receives to another router? Why?

  29. If a routing table has a rule that holds all zeros for the destination address and the subnet mask, what is the purpose of that rule? Where would that rule occur in a Windows routing table? Where would it occur in a Cisco routing table?

  30. What rules are automatically put in a router's routing table? What code would a Cisco router assign to such a rule? What do we call rules that are entered by an administrator? What is the Cisco code for that kind of rule? What is the third way a rule is put in a routing table?

  31. What command can you give to a Windows device to see its routing table? How about a Cisco router?

  32. What is the difference between basic NAT and PAT?

  33. What is a routing metric? What are some properties that are used for metrics?

  34. What is the difference between Distance Vector and Link State protocols? Which category does each of these belong to: RIP, BGP, OSPF, IS-IS?

  35. What is the hop count limit for RIP?

  36. How is a Yost cable different from one that has an RJ-45 connector on both ends? What is it used for?

  37. When you connect to a Cisco router on its console port, what program might you use to make the connection? What are the recommended configuration settings?

  38. Other than the console port, how might you expect to be able to configure a router?

  39. Which port on a home router is connected to a cable modem?

  40. What is the difference between a connection-oriented protocol and a connectionless protocol? Give an example of each type.

  41. What are the three transmissions in a three-way handshake? When is it used?

  42. What are the four transmissions in a TCP session termination if it is closed gracefully?

  43. What are the four steps to a DHCP address negotiation? What ports are used by each device?

  44. What protocol is used for a ping? Which protocol drives the request?

  45. What is the range for well known port numbers? What can we say about the kind of devices that typically use them?

  46. What are ephemeral port numbers? What kind of devices typically use them?

  47. What will we see if we enter the command netstat -n?

  48. What does an IP address need added to it to be called a socket?

  49. What is the significance of a port being in CLOSE_WAIT state? How is that different from a TIME_WAIT state?

  50. Issuing the command netstat -ano will give you process ID numbers for each live connection. Why might this lead you to run Windows Task Manager next?

  51. What protocol commonly uses port 80? What port would we expect to use when making a purchase?

  52. What are the ports used by Telnet and SSH?

  53. If a user cannot send email, which port should you check to see if it is blocked? What ports would you check if the use cannot retrieve email?

  54. Which email retrieval protocol pulls your mail down and deletes if from the server? Which lets you read it and leaves the original on the server?

  55. What kind of networks us WINS?

  56. What is a hosts file? Where would you typically look for it?

  57. What is at the top of the DNS hierarchy? What is just below that?

  58. What is an FQDN?

  59. What does a DNS server keep in its Cached Lookups folder?

  60. What is an A record? How is it different from an AAAA record? Where are such records kept?

  61. What is an MX record?

  62. In a system that uses WINS, what is the equivalent of a hosts file?

  63. What is nbtstat? What kind of names does it work for?