Network Layer Subnetting, Fragmentation Due: Oct 22/23

Q1. Suppose a network allows to pass datagrams of size less than or equal to 1,500 bytes (including header).

Assuming the standard size of IP header i.e. 5 octets (20 byte). How many datagrams would be required to send a huge

file of 5 million bytes?

Q2. Consider an IP packet with the following values in the IP header.

Total length of IP packet is 1000 bytes.

Identification id is 2390

Length of IP header is 20 bytes

DF Flag = 0

MF Flag = 0

Fragment offset = 0

Suppose that the packet is sent on a link that has MTU = 512 bytes

a. How many fragments will be created?

b. After the fragmentation is performed, create a table as below to provide the value of the following fields for

each of the fragments

Fragment1 Fragment2 …………………… Fragmentn-1 Fragmentn

Total Length in

bytes

DF Flag

MF Flag

Fragment Offset

Identification id

Q3. University of Suwon (USW) has the following network addresses 150.80.0.0/16. USW wants to distribute these

blocks to 2600 students as follows.

a. The School of Engineering has 200 departments; each department has 128 students

b. The School of Humanities has 400 departments; each department has 16 students.

c. The School of Architecture has 2000 departments; each department has 4 students.

For each school, design the sub-blocks and give the slash notation for each block. Also find out how many addresses

are still available/free after assignment.

Q4. Daewon Pharmaceutical, a leading pharmaceutical company in Korea, has received the IP address 201.123.5.0/24.

They have 3 offices in 3 different locations: Seoul, Incheon, Suwon. The Seoul office has 40 hosts, the Incheon office

has 30 hosts, and the Suwon office has 25 hosts. They also expect that the number of hosts may increase in the future

by 20%. They are also planning to set up a new office in Anyang with 10 hosts.

How should the 201.123.5.0/24 be subnet into 4 equal sizes? For each subnet, write down the following information:

For Seoul

a. Network Address : _________________________________________

b. Broadcast Address : _________________________________________

c. Subnet Mask :_________________________________________

d. Range of IP address :_____________________________ to ____________________

For Incheon

a. Network Address : _________________________________________

b. Broadcast Address : _________________________________________

c. Subnet Mask :_________________________________________

d. Range of IP address :_____________________________ to ____________________

For Suwon

a. Network Address : _________________________________________

b. Broadcast Address : _________________________________________

c. Subnet Mask :_________________________________________

d. Range of IP address :_____________________________ to ____________________

For Anyang

a. Network Address : _________________________________________

b. Broadcast Address : _________________________________________

c. Subnet Mask :_________________________________________

d. Range of IP address :_____________________________ to ____________________