Instructor:
Seung Bae Im
Closed Book,
Closed Notes.
Note: Write your name on each page of answer sheet.
Clearly label each answer. DO NOT WRITE ON THE BACK OF A PAGE!
1.
(50 Points)
(a)
The
bridges used to connect Ethernets together are called “Transparent(or learning)
bridges”. Describe their functions and state why they are called with the above
name.
(b)
State
why bridges can not be used in Internet(where large number of networks are
connected).
(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 DNS(Domain Name Service).
(g)
Describe
why all 1’s and all 0’s are not useable in either (sub)network address or host
addresses.
(h)
Describe
the functions/usages of RFCs(Request For Comment).
(i)
Describe
how TCP adjusts its timeout duration dynamically.
(j)
Explain
where and how the “proxy” ARP(Address Resolution Protocol) is used.
2.
(20 points) Using a web client and web
server connection as an example, describe operations of TCP/IP’s
client/server(socket) programs including the following terms: socket,
well-known port numbers(port 80), ephemeral port numbers, uniqueness of a
connection(5 tuples), concurrent servers, child process.
3. (2 points each) Mark 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 your NT server?
a.
ping.exe
b.
arp.exe
c.
nbstat.exe
d.
netstat.exe
3.
Your
company has a network containing 15 subnets and a Class B address of
150.47.0.0. What mast 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.
Your
company has a Class C address of 192.123.33.0. The network has four subnets;
three more will be added. Which subnet mask will give you the most host IDs per
subnet?
a.
255.255.255.248
b.
255.255.255.240
c.
255.255.255.224
d.
255.255.255.192
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
6.
Which of the
following items are TCP/IP diagnostic utilities? (Choose all that apply)
a.
Packet InterNet Groper(Ping)
b.
IPLookup
c.
nslookup
d.
NETSTAT
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
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
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
your network, which of the following must you consider?
a.
the types of computers used on the network. (Choose all that apply)
b.
the IP address class
c.
the number of physical segments on your network
d.
the potential for network growth
11. Your company has been assigned the
network address 161.75.0.0. You have 10
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.
255.255.240.0
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.
tracert
d.
nslookup
14. Your company has been assigned a network
ID of 207.240.108.0. You are going to divide the network into multiple
networks. You want to have up to 60 host IDs on each subnet. The subnet mask
that will let you create the most number of subnets is which of the following?
a.
255.255.255.192
b.
255.255.255.224
c.
255.255.255.240
15. T/F
___ Every host computer must have an IP address and but a router does not have
to have an IP assigned.