Instructor:
Seung Bae Im
Closed Book,
Closed Notes. Name:_________________________________
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! If you have any question,
write your assumptions clearly and answer the question.
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
why the Internet Address space is running out(there’s not much address spaces
are left to be assigned).
(e)
What
are the current/future solutions to the above problem(question (d))?
(f)
Describe
fragmentation and reassembly process of IP datagrams including the term,
“16-bit Identification” field in IP packet.
(g)
Describe
how the ARP(Address Resolution Protocol) operates(not why it is needed).
(h)
Explain
why subnetting is needed.
(i)
What
is a subnet mask?
(j)
Describe
how the socket-to-socket connection is established in TCP.
(k)
Describe
how the “traceroute” program uses TTL(Time To Live) field to achieve its
function.
2. (9 points) In TCP/IP protocols, if an application layer is written using UDP as
the transport layer protocol, then what kinds of things the application layer
need to take care of to achieve reliable connection-oriented functions between
peer applications.
3. (10 points) Point
out the differences between “Distance Vector(e.g. RIP)”
algorithms and “Link State(e.g. OSPF)” algorithms.
4. (2 points each)
Mark(circle) the answers on the problems. Some problems have multiple answers.
Choose all that apply.
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.
229.7.2.0
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
e.
ipconfig.exe
3. Your
company has a network containing 60 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
f.
255.255.192.0
4. 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. IRTF
d. NSF
e. IANA
f.
All of Above
5. 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. SNMP
f.
All of above
6. 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
7. 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
8. A
class C IP address uses how many octets to identify the Network ID?
a.
one
b.
two
c. three
d.
four
9. 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
10. 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
11. Christine’s
department has been assigned the network address 143.5.3.0. Christine’s
supervisor tells her to use the subnet mask of 255.255.255.224. How many host IDs will be available for each
subnet?
a.
32
b. 30
c.
62
d.
64
12. 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
e.
arp
13. 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
e.
your
station’s IP address