Cs University
Network Protocols and Communication
Practice Exercises & Quiz
Exercise 1: Consider the figure below:
1. Find and correct the errors in the above topology.
2. Give instructions for configuring R1 router interfaces.
, 3. Give routing configuration instructions for routing packets to subnetworks and
the Internet (assuming router interfaces R1 and R2 are already configured).
4. Give router R1's routing table.
5. Give router R2's routing table.
Exercise 2:
We wish to send a message and an attached file via "electronic mail" from site A
to site B. It is assumed that :
- e-mail uses the TCP/IP protocol.
- the message and attached document are 8.5 Kb in size
- under TCP, the length of messages exchanged is 1500 characters.
- the window size is initialized at 1 message and doubles each time the sender
receives a positive acknowledgement; if the receiver receives a negative
acknowledgement, the window size is divided by 2.
- ISNA (Initial Sequence Number for A) =1000.
- ISNB (Initial Sequence Number for B) =1500.
1. Specify the value of each TCP header field (only the necessary fields) for the
three phases (connection, transfer, connection release) during the complete
transfer of this mail (it is assumed that no message will be lost).
2. Repeat the 2nd question if the 3rd and 5th messages are lost.
Network Protocols and Communication
Practice Exercises & Quiz
Exercise 1: Consider the figure below:
1. Find and correct the errors in the above topology.
2. Give instructions for configuring R1 router interfaces.
, 3. Give routing configuration instructions for routing packets to subnetworks and
the Internet (assuming router interfaces R1 and R2 are already configured).
4. Give router R1's routing table.
5. Give router R2's routing table.
Exercise 2:
We wish to send a message and an attached file via "electronic mail" from site A
to site B. It is assumed that :
- e-mail uses the TCP/IP protocol.
- the message and attached document are 8.5 Kb in size
- under TCP, the length of messages exchanged is 1500 characters.
- the window size is initialized at 1 message and doubles each time the sender
receives a positive acknowledgement; if the receiver receives a negative
acknowledgement, the window size is divided by 2.
- ISNA (Initial Sequence Number for A) =1000.
- ISNB (Initial Sequence Number for B) =1500.
1. Specify the value of each TCP header field (only the necessary fields) for the
three phases (connection, transfer, connection release) during the complete
transfer of this mail (it is assumed that no message will be lost).
2. Repeat the 2nd question if the 3rd and 5th messages are lost.
