Instructor:
Seung Bae Im
Closed Book,
Closed Notes.
If you have
any question, write your assumptions clearly and answer the question.
Note: Write your name on each page of answer sheet.
Clearly label each answer. DO NOT WRITE ON THE BACK OF A PAGE! They will not be
graded!
1.
(55 Points)
(a)
Point
out the differences between a bridge and a router.
(b)
What
is the difference between “Ethernet hub” and “Ethernet Switch”?
(c)
Describe
TCP’s flow control mechanism including the term, “credt”.
(d)
Explain
where and how the RARP(Reverse Address Resolution Protocol) is used.
(e)
Describe
fragmentation and reassembly process of IP datagrams including the term,
“16-bit Identification” field in IP packet.
(f)
Describe
the function of ARP(Address Resolution Protocol).
(g)
Explain
where and how the “proxy” ARP(Address Resolution Protocol) is used.
(h)
What
is a subnet mask?
(i)
Describe
the functions/usages of RFCs(Request For Comment).
(j)
Describe
how the “traceroute” program uses TTL(Time To Live) field to achieve its
function.
(k)
Describe/constrast
between “Connectionless service” & “Connection-oriented service”.
2. (3 points each)
Mark(circle) the answers on the problems.
1.
You work
for a government agency that has been assigned a class B network address. Which of the following addresses could be
yours?
a. 126.1.0.0
b.
131.107.2.89
c. 190.7.2.0
d. 131.107.256.80
2.
When you
want to view a list of IP address to physical address mappings; which utility
would you use from a workstation?
a. ping.exe
b.
arp.exe
c. nbstat.exe
d. netstat.exe
3.
Your
company has a network containing 12 subnets and a Class B address of
135.49.0.0. What subnet mask would you use to allow the largest number of host
IDs per subnet?
a. 255.255.224.0
b. 255.255.240.0
c.
255.255.248.0
d. 255.255.252.0
e. 255.255.254.0
4.
Which one
of the following most accurately describes TCP/IP sockets?
a. A
socket designates the connection between two machines
b.
A socket is an entry
point from IP layer to TCP layer
c. A
socket is a Service Access Point that an application uses to invoke the
services of UDP or TCP.
d. A
socket is a two way communication link between two machines.
5.
The ISOC
was created in 1992 and is a global organization responsible for the
internetworking technologies and applications of the Internet. ISOC (Internet Society) has which of the
following groups within its organization? (Choose all that apply)
a.
IAB
b.
IETF
c.
IANA
d.
IRTF
e.
All of Above
6.
Which of
the following items are TCP/IP diagnostic utilities? (Choose all that apply)
a.
Packet InterNet
Groper(Ping)
b.
Traceroute
c.
nslookup
d.
NETSTAT
e.
All of above
7.
Address Resolution
Protocol(ARP) carries out the process of mapping a host’s IP address to its
_________.
a. NetBIOS
name
b. Fully
Qualified Domain Name
c.
hardware address
d. computer
name
e. All
of above
8.
Which
statement best describes the Internet Control Message Protocol (ICMP)?
a. informs
routers that hosts of a specific group are available on a network
b.
attempts to report
errors and provide feedback on specific conditions on behalf of IP
c. attempts
to make IP a reliable protocol
d. responsible
for addressing and routing packets between hosts
e. All
of above
9.
A class C
IP address uses how many octets to identify the Network ID?
a. one
b. two
c.
three
d. four
10. When making the determination to subnet a
given network, which of the following must you consider?
a. the
types of computers used on the network.
b.
the IP address class
c.
the number of physical
segments on your network
d.
the potential for
network growth
e.
All of above
11. Your company has been assigned the
network address 161.75.0.0. You have 20
physical segments on your network. You
will use a router on one subnet to connect all computers on the network to the
internet. What is the correct subnet
mask for the network?
a. 255.255.255.255
b. 255.255.0.0
c. the
subnet mask assigned by InterNIC
d.
255.255.248.0
e.
None of above
12. Christine’s company has been assigned the
network address 143.5.0.0. Her network will grow to 56 subnets over the next
year. Christine’s supervisor tells her to use the subnet mask of
255.255.252.0. How many host IDs will
be available for each subnet?
a. 1024
b.
1022
c. 62
d. 64
13. Ben receives a complaint from an employee
in subnet E that when they retrieve files from a server in subnet F, it takes
twice as long as when they retrieve files from a server in subnet D. What can Ben use to identify the path that
the data packets take as they pass through the routers?
a. ping
b. netstat
c.
traceroute
d. nslookup
14. Which one of the following is called
“loopback address”?
a.
224. 0. 0. 1
b. 124.0.0.1
c. 127.0.0.1
d. 255.255.255.255
15. T/F
___ PPP(Point-to-Point Protocol) uses character stuffing to achieve data
transparency.