Mid-term for Network Class, Dominican University, May 2002

Make your written replies short and to the point

 

1.                    What does CSMA/CD stand for?

Carrier Sense, Multiple Access, Collision Detect

2.                    The CS portion performs which function?

A station listens to the wire for a transmission signal  (I need a little more than the name for this one and the next one)

3.                    The MA function represents which capability?

Everyone attached to the network can attempt to send simultaneously

4.                    The CD function represents which capability?

Each station listens to the line while it is signaling.  If multiple stations attempt to send simultaneously, frames will collide generating an error signal.  When the sending station hears the error while it is signaling, it knows its frame collided and backs off for a random time before resending

5.                    A full mesh network connecting 7 stations will require how many connections:

a.        23

b.       18

c.        21

d.       25

e.        20

f.         22

 

c.        21

 

6.                    How will a star-bus or hybrid topology network respond if a computer fails?

The network will fail.

7.                    How will a bus topology network respond if a computer fails?

No effect

8.                    How will a star-bus topology network respond if a switch goes down?

The pieces of the network on either side will become isolated, as will all attached ports

9.                    What is the maximum cable run for a 100BASE-Tx network?

100 m

10.                 What is the maximum cable run for a 10BASE5 network?

500 m

11.                 What is the maximum cable run for a 10BASE2 Network?

185 m

12.                 What does the 5-4-3 rule represent?

5 segments, four repeaters (hubs), three populated segments

13.                 What are the 7 layers of the OSI model?

Application: Connect the user to the network

Presentation:  Determine the format in which the data will be presented

Session:  Establish the ground rules for a successful complete communication

Transport: Determine whether the transmitter and receiver have the same data connected to the same application

Network: Create a logical address space permitting traffic to be routed from one network to another

Data Link: Create frames that can be delivered from one local station to another using physical (non-logical) addresses

Physical:  Establish the signal specifications required for a successful communication

14.                 What two addresses characterize Ethernet at the Layer 2?  Give the answer in the order seen in the E’net frame.

Destination MAC, Source MAC

15.                 What two addresses characterize the TCP/IP layer 3?  Give in the order seen in the packet.

Source IP address, Destination IP address

16.                 What two values represent the application to which the layer 4 segment will deliver the payload data.  Give in the order seen in the segment.

Source port, destination port

17.                 What is the destination address of an ARP request?

FF-FF-FF-FF-FF-FF

18.                 What is the ethertype of an ARP packet?

0x806

19.                 What is the ethertype of a DNS request?

0x800

20.                 What is the protocol type for ICMP?

Protocol = 0x01

21.                 In which header will this protocol type appear?

IP header

22.                 What is the protocol type for a packet whose payload is destined for the TCP stack:

a.        0x01

b.       0x02

c.        0x06

d.       0x11

e.        0x32

 

c.        0x06

 

23.                 What is the protocol type for a packet whose payload is destined for the UDP portion of the layer 4 stack:

a.        0x01

b.       0x02

c.        0x06

d.       0x11

e.        0x32

 

d.       0x11

 

24.                 What are the four different types of Ethernet frame that are commonly seen:

a.        DIX EthernetII

b.       802.5

c.        802.2

d.       802.1d

e.        802.5 SNAP

f.         802.1q

g.       802.3 SNAP

h.       802.11b

i.         802.3 Novell

j.         FDDI SNAP

 

a.     DIX EthernetII

c.     802.2

g.       802.3 SNAP (802.2 SNAP, in truth)

i.         802.3 Novell

 

25.                 Contrary to the text (Figure 3-3), only three layers of the OSI model actually result in encapsulation of the previous layer in a new header (an possibly a trailer).  What are they?

Transport

Network

Data Link

26.                 Which layer usually adds a trailer?

Data Link

27.                 What is it called in Ethernet (abbreviation and full text)?

FCS/Frame Check Sequence

28.                 What will the IPX/SPX address for a host be if it is on a network called FEEDFACE and it has a MAC address of 00-0c-b0-4a-de-03?

FE-ED-FA-CE-00-0c-b0-4a-de-03

29.                 TCP is considered which sort of protocol:

a.        Stateful

b.       Connectionless

c.        Connection-oriented

d.       Stateless

 

a.     Stateful

c.     Connection-oriented

 

30.                 NetBEUI is a routable protocol:

a.        True

b.       False

 

b.     False

 

31.                 As such it will have a fully developed OSI network layer structure:

a.        True

b.       False

 

b.     False

 

32.                 As such it will have a fully developed OSI transport layer structure:

a.        True

b.       False

 

b.     False

 

33.                 IEEE protocol 802.1d represents which protocol (use internet)?

Spanning Tree Protocol

34.                 What does this protocol use to communicate (from text)?

BPDU – Bridge Protocol Data Unit

35.                 UTP stands for?

Unshielded Twisted Pair

36.                 STP stands for?

Shielded Twisted Pair

37.                 How many connectors are in an RJ-45 connector?

8

38.                 Will an RJ-45 jack from 10BASE-T cabling work reliably for a 1000BASE-T connection?

No

39.                 Will and RJ-45 jack from 1000BASE-T cabling work reliably for 10BASE-T connections?

Yes

40.                 If a fiber-optic cable has a core diameter of 6 microns, will it be single- or multi- mode?

Single-mode

41.                 If a fiber-optic cable has a core diameter of 62.5 microns will it be single- or multi- mode?

Multi-mode

42.                 If you connect a pair of switches together, what kind of cabling is required for proper operation?

Cross-over

43.                 If you connect a router to a switch what kind of cable is required?

Patch (straight-through)

44.                 If you connect a computer to a hub what kind of cable is required?

Patch (straight-through)

45.                 If you connect a router directly to a computer what kind of cable is required?

Cross-over

46.                 Your client to your ISPs mail server downloads the mail to the local computer.  What port (changed from protocol, May 10, @ 12:30 P.M.) number does it use to access the mail server for the download:

a.        25

b.       53

c.        110

d.       143

e.        80

f.         21

 

c.     110          (POP3)

 

47.                 Your mail client is sending mail to your ISP’s mail server for delivery to a remote station.  Which port (changed from protocol, May 10, @ 12:30 P.M.) number will it use:

a.        25

b.       53

c.        110

d.       143

e.        80

f.         21

 

a.     25            (SMTP)

 

48.                 Which transport protocol will it use to send the mail:

a.        ICMP

b.       IGMP

c.        TCP

d.       UDP

e.        AH

f.         ESP

 

c.        TCP

 

49.                 In which field of the header selected in 48 will the port number  (changed from protocol, May 13 @ 7:00 A.M.) selected in 47 be inserted?

Destination port

50.                 Which three address ranges are reserved in RFC 1918 for private use:

a.        10.0.0.0/255.255.0.0

b.       172.16.0.0/20

c.        10.0.0.0/255.0.0.0

d.       192.168.0.0/255.255.255.0

e.        172.16.0.0/255.240.0.0  (changed from 255.248.0.0, May 10, @ 12:30 P.M.)

f.         10.0.0.0/24

g.       192.168.0.0/255.255.0.0

h.       192.168.0.0/255.252.0.0

i.         172.168.0.0/255.224.0.0

 

c.        10.0.0.0/255.0.0.0

d.       172.16.0.0/255.240.0.0 

g.       192.168.0.0/255.255.0.0

 

51.                 For the network 10.32.0.0/255.248.0.0, what address range will be included in the network:

a.        10.32.0.0 – 10.35.0.0

b.       10.32.0.0 – 10.47.0.0

c.        10.32.0.0 – 10.39.0.0

d.       10.32.0.0 - 10.32.43.0.0

e.        10.32.0.0 – 10.36.0.0

 

c,     10.32.0.0 – 10.39.0.0

 

52.                 What is a fast way to determine this number of network values included when you are given the mask in decimal form?

Subtract the last non-zero octet value from 256.  For the network mask 255.255.240.0 the subsumed number of networks is 256 – 240 = 16

53.                 What is the network range for default Class A networks?

0.0.0.0 to 127.0.0.0, but remember 0.0.0.0 and 127.0.0.0 are reserved

54.                 What is the network range for default Class B networks?

128.0.0.0 to 191.255.0.0

55.                 What is the network range for default Class C networks?

192.0.0.0 to 223.255.255.0

56.                 What does Ping IP address test?

Basic IP connectivity

57.                 What does PING Computername test?

IP connectivity using name resolution (DNS/WINS)

58.                 What does the tracert output show?

The set of routers between the host and the target

59.                 What is the APIPA address range?

169.254.0.0/255.255.0.0

60.                 Who registered this range with IANA?

Microsoft

61.                 RIP is which kind of routing protocol?

a.        Link State

b.       Distance Vector

c.        Distance Path

 

b.       Distance Vector

 

62.                 RIP advertises its:

a.        Its entire routing table to all associated routers

b.       Changes in its routing table to its neighbors (out every interface)

c.        Its full routing table to its neighbors (out every working interface)

d.       Changes to all associated routers

 

c.        Its full routing table to its neighbors (out every working interface)

 

63.                 How often does it advertise?

Every 30 sec.

64.                 What is the Ethernet broadcast address?

FF-FF-FF-FF-FF-FF

65.                 On the network 10.0.0.0/255.0.0.0 what will the IP broadcast address be?

10.255.255.255

66.                 What special activity does the MAC address 01-00-5e-06-03-0c represent?

Multicast destination

67.                 What is the most probable IP address that sourced this address (represent the first byte of the IP address with an X because it cannot be know from this data)?

X.6.3.12

68.                 OSPF tells what about itself when it advertises to the network (choose all)?

a.        Its interfaces

b.       Their speeds

c.        Their status

d.       Its name (or reference IP address)

 

a.        Its interfaces

b.       Their speeds

c.     Their status

d.     Its name (or reference IP address)

 

69.                 OSPF is which kind of routing protocol:

a.        Link State

b.       Distance Vector

c.        Distance Path

 

a.     Link State

 

70.                 BGP4 (Border Gateway Protocol, ver. 4) is typically used:

a.        On large corporate LANs

b.       To route between routing domains on the internet

c.        On small LANs

d.       Only on old legacy LANs

 

a.        On large corporate LANs (OK, too, but c. is the answer that I really wanted, it is the answer the exam aims toward)

c.        To route between routing domains on the internet

 

71.                 What is the main function of ICMP?

To provide error detection to TCP/IP

72.                 What is stored in the ARP table?

MAC addresses of recently contacted hosts

73.                 Which MS tool allows you to examine the NetBIOS configuration of your local computer or of a remote computer?

NBTSTAT

74.                 If you wish to examine the NetBIOS functions associated with the remote computer Tech09, what command would you issue in a MS Windows 2000 computer?

NBTSTAT –a TECH09

75.                 If you wish to examine the NetBIOS functions associated with the remote computer 10.2.14.59, what command would you issue in a MS Windows 2000 computer?

NBTSTAT –A 10.2.14.59

76.                 What is an advantage of using a print queue server?

Central management of printer ports and print queues

77.                 What does a DNS server do?

Convert computer/web addresses to IP addresses

78.                 How does a Token Ring client send a message/packet onto the network:

a.        It seizes a token when it is available, modifies it, and attaches it data

b.       It broadcasts the message into the transmission medium

c.        It waits until it is queried for a message

 

a.     It seizes a token when it is available, modifies it, and attaches it data

 

79.                 Windows active directory is based on which service:

a.        Network Information Service (NIS/NIS+)

b.       X.500

c.        Lightweight Directory Access Protocol (LDAP)

d.       X .400

e.        Novell Directory Service

f.         Directory Access Protocol (DAP)

 

c.     Lightweight Directory Access Protocol (LDAP)

 

80.                 Public key cryptography uses:

a.        Symmetric keys

b.       Asymmetric keys

c.        Shared secret keys

 

b.     Asymmetric keys