EC2356 - COMPUTER NETWORKS LABORATORY LABORATORY MANUAL ... LAB MANUAL.pdf · EC2356 - COMPUTER NETWORKS LABORATORY LABORATORY MANUAL ... the answer to the viva-voce questions

Dr.NNCE ECE / VI SEM NETWORKS LAB - LM

1

EC2356 - COMPUTER NETWORKS LABORATORY

LABORATORY MANUAL

FOR IV SEMESTER B.E (ECE)

ACADEMIC YEAR(2013-2014)

(FOR PRIVATE CIRCULATION ONLY)

ANNA UNIVERSITY CHENNAI-600 025

(REGULATION 2008)

DEPARTMENT OF ELECTRONICS AND COMMUNICATION

ENGINEERING

DR.NAVALAR NEDUNCHEZHIYAN COLLEGE OF ENGINEERING,

THOLUDUR 606 303, CUDDALORE DIST.


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UNIVERSITY PRACTICAL EXAMINATION

Allotment of Marks

Internal assessment = 20 marks

Practical examination = 80 marks

----------------------

Total = 100 marks

----------------------

INTERNAL ASSESSMENT (20 MARKS)

Staff should maintain the assessment register and the Head of the Department should

monitor it.

Split up of internal marks

Record = 10 marks

Model exam = 5 marks

Attendance = 5 marks

----------------------

Total = 20 marks

----------------------

UNIVERSITY EXAMINATION

The exam will be conducted for 100 marks. Then the marks will be calculated to 80

marks

Split up of practical examination marks

Aim and Procedure : 10 marks

Theory : 10 Marks

Diagram : 20 Marks

Tabulation : 15 Marks

Verification : 25 Marks

Graph and Result : 10 Marks

Viva Voce : 10 Marks

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Total : 100 Marks

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GENERAL INSTRUCTIONS FOR LABORATORY CLASSES

o Enter the Lab with CLOSED FOOTWEAR.

o Boys should “TUCK IN” the shirts.

o Students should wear uniform only.

o LONG HAIR should be protected, let it not be loose especially near ROTATING

MACHINERY.

o Any other machines / equipments should not be operated other than the prescribed

one for that day.

o POWER SUPPLY to your test table should be obtained only through the LAB

TECHNICIAN.

o Do not LEAN and do not be CLOSE to the rotating components.

o TOOLS, APPARATUS and GUAGE sets are to be returned before leaving the lab.

o HEADINGS and DETAILS should be neatly written

i. Aim of the experiment

ii. Apparatus / Tools / Instruments required

iii. Procedure / Theory / Algorithm / Program

iv. Model Calculations

v. Neat Diagram / Flow charts

vi. Specifications / Designs Details

vii. Tabulations

viii. Graph

ix. Result / discussions .

o Before doing the experiment, the student should get the Circuit / Program approval

by the FACULTY - IN - CHARGE.

o Experiment date should be written in the appropriate place.

o After completing the experiment, the answer to the viva-voce questions should be

neatly written in the workbook.

o Be PATIENT, STEADY, SYSTEMATIC AND REGULAR.


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LIST OF EXPERIMETS

1. PC to PC Communication

2. Parallel Communication using 8 bit parallel cable

3. Serial communication using RS 232C

4. Ethernet LAN protocol

5. To create scenario and study the performance of CSMA/CD protocol through

simulation

6. Token bus and token ring protocols

7. To create scenario and study the performance of token bus and token ring protocols

through simulation

8. Wireless LAN protocols

9. To create scenario and study the performance of network with CSMA / CA protocol

and compare with CSMA/CD protocols.

3. Implementation and study of stop and wait protocol

4. Implementation and study of Goback-N and selective repeat protocols

5. Implementation of distance vector routing algorithm

6. Implementation of Link state routing algorithm

10.Implementation of Data encryption and decryption

11.Transfer of files from PC to PC using Windows / Unix socket processing


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CONTENTS

S.NO LIST OF EXPERIMENTS

Pa

ge

No

01 Ethernet 6

02 a. Token Ring

b. Token Bus

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03 Wireless LAN protocol 14

04 Stop and wait ARQ protocol 17

05 a. Selective Reject ARQ protocol

b. Go-Back-N ARQ protocol

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ROUTING ALGORITHM’S 21

06 Distance vector algorithm 25

07 Link state algorithm 28

08 a. Data encryption and decryption shifting algorithm

b. RSA algorithm

31

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a. PC to PC File transfer protocol HTTP web browsing.

b. FTP-File transfer protocol

c. SMTP – E-mail

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10 a. PC to PC communication (Parallel)

b. PC to PC communication (Serial)

40


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Exercise Number : 1

Title of the Exercise : ETHERNET

Date of the Exercise :

OBJECTIVE (AIM) OF THE EXPERIMENT

To create the scenario and study the performance of Ethernet LAN protocol through

simulation and using trainer kit.

FACILITIES REQUIRED AND PROCEDURE a) FACILITIES REQUIRED TO DO THE EXPERIMENT:

S.NO APPARATUS SPECIFICATION QUANTITY

1. PC - -

2. LAN Trainerkit - 1

3. Network simulator - -

INPUT PARAMETERS:

No of nodes : 2 to 4

Frame interval : 250 ms to 1000ms

Frame size : 64 bytes to 1500bytes

Maximum back off time : 4 to 32

Error generation : 10-9 10-6 and 10-3

TRANSFERRING A DATA FROM ONE NODE TO ANOTHER:

Each node is numbered as 1,2,3 and 4.

Each node is identified with its own IP address.

From any node file from the system can be opened for transmission.

This file can be sent to any destination node.

At the time of sending, sender window and receiver window are opened in the

respective nodes and data transfer occurs. The progress bar in these windows shows

the amount of data transferred and received.

In each node, one trace window is available in which data transfer information with

time stamp appears continuously.

At the end the data transfer, result appears with appearance parameters.


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STORING OF TRANSFERRED FILES, RESULTS AND TRACES:

For Ethernet operation, one directory namely Ethernet is created in the simulator

directly in C drive. For 4 nodes node 1, node 2, node 3 and node 4 subdirectories are

created.

Now can be sender or receiver when one file transferred from one node to another

node the data file is stored in destination node. Result is stored as file with the name.

The result is stored in excel format which data can used for the graph.

There is a provision in every mode to store the trace window information in

respective node. The store in excel format.

CONNECT AND DISCONNECT FACILITY:

At any instant, one node can be disconnected from the shared medium and other later

whenever it necessary, the node can be reconnected.

PAUSE AND RESET FACILITY:

At any time, the simulation can be stopped and can be continued. There is a reset

option in which the process will stop.

PROCEDURE:

Select 2 nodes and carryout data transfer from one node to another node.

Select 2 nodes and carryout data transfer between 2 nodes simultaneously and

analyse.Repeat the experiment for different packet sizes, different maximum back off

time and different error generation

Select 3 nodes and carryout data transfer between the nodes simultaneously and

analyse.Repeat the experiment changing the input parameter.

Select 4 nodes and do the data transfer and analyse the result when the data transfer is

going on. Disconnect one node and observe and record

RESULT:

Thus the performance of Ethernet LAN protocol through simulation and using

trainer kit was verified successfully.


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VIVA QUESTIONS:

1.What is Ethernet?

Ethernet is a physical and data link layer technology for local area

networks (LANs).

2.What is meant Data Communication?

Data Communication is a exchange of data between two devices via some

form of transmission medium.

3.What are the fundamental characteristics of data communication?

Delivery: The system must deliver data to the correct destination.

Accuracy: The system must deliver data accurately.

Timeliness: The system must deliver data in a timely manner.

4.What are the components used in data communication?

Message, Sender, Receiver, Medium, Protocol.

5.How can you considered data communication ,what are they?

Data communication is considered ,

Local- if the communicating devices are in the same building

Remote –Geographical area.

http://compnetworking.about.com/cs/lanvlanwan/g/bldef_lan.htm

http://compnetworking.about.com/cs/lanvlanwan/g/bldef_lan.htm


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Exercise Number : 2.a

Title of the Exercise : TOKEN RING



To create the scenario and study the performance of token ring LAN protocol

through simulation and using trainer kit.



1. PC - -



INPUT PARAMETER:

No of nodes – 2 to 4

Frame Interval – 250ms by defeat

Frame size – 512bytes -2048bytes

Error Generation – 10-9,10-6 and 10-3

TRANSFERING A DATA FILE ONE NODE TO ANOTHER:

Each node is numbered as 1,2,3 and 4.

Each node is identified with its own input address.

In order to correct the node in the ring, connect switch is to be used.

From any node file from the system can be opened for transmission.

This file can be sent to any destination nodes.

At this time of sending, the progress bar in these windows the amount of data

transferred and received.

In each node one trace window is available in which the data transfer information

with time stamp appears continuously.

At end of the data transfer result appears with performance parameter.

TOKEN HOLD ON TIME AND TOKEN PRIORITY:

The default frame interval is 250ms in order to send many data packets sequentially

the token hold on time can be changed to higher value using this facility, the token

can be retained node for long time.

The priority of the node also can be stated.


At any instant one node can be disconnected from the shared medium. And later

whenever it is necessary the node can be reconnected.


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At any time the simulator and can be continued. There is reset option in which the

process will stop.

TOKEN RING OPERATION:

Initially the input address of the node are given and nodes are connected to the ring

network. Now, token is placed between the nodes connected. 2 to 4 nodes can be connected

in the ring. As per the priority of the nodes, the token will pass. The priority of the node can

be changed and then the token passing will take route as per the priority allotment.

The token hold on time can also be changed when the data is transferred the number

of frames that all transferred form the mode depends upon the token hold on time on time of

node after the token hold on time the token is passed on to the next priority node.

Duration the file transfer suppose one node in the ring is disconnected then one

messages window appears and ask for triggering the ring leaving the disconnected node if

the answer is yes .the particular node is disconnected and other nodes from a ring and

activities continue. If the answer is no then all the nodes are disconnected. In this cases all

the nodes all to be reconnected using connect switch

STORING OF TRANSFERRED RULES, FILES RESULT AND TRACES :

For token ring operation, one directory namely token ring is created in the simulator

directory in c drive for 4 node, node2, node3 and node4 slur directories all created.

Node can be a sender or receiver when one file is transferred from one node to

another the data file is stored in destination mode. Result is stored as a file with the

name part is stored in sender node. The result file is stored in excels format form

which data can be used for graph.

There is a provision in every need to store the trace window

Information in the respective mode they are also called in excel format.

PROCEDURE:

Select 2 nodes and carryout data transfer form node to another node select 2 nodes

and carryout data transfer between 2 nodes simultaneously and analyse. Repeat the

experiment changing the parameters disconnect one redoes and answer to the

question yes and observe the operation and record it disconnect the node and answer

to the question no and observe the generation and record it.

Select 4 nodes and do the data transfer when the data transfer is going on disconnect

one node and observe and record the effect.

RESULT:

Thus the performance of token ring LAN protocol through simulation and using

trainer kit was verified successfully.


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Exercise Number : 2.b

Title of the Exercise : TOKEN BUS



To create and scenario and study the performance of token bus through simulation

and verify LAN trainees kit.



1. PC - -



INPUT PARAMETERS:

No of nodes -2 to 4

Frame interval -250 ms to 1000 ms

Frame size -512 bytes to 2,4,8 bytes

Error generation -10-9,10-6 and 10-3

TRANSFERRING A DATA FILE ONE NODE TO ANOTHER:

Each node is identified with its own input address

Each node is numbered with the priority no of that given to the node

In order to connect the node in the token bus connect switch to be used

Form any node. File form the system can be opened for transmission

This file can be sent to any destination node.

At the any time of sending. Sender window and receiver window are opened in the

respective nodes and the data transfer occurs the progress bar in there windows shows

the amount of data transferred and received.

In each node one trace window is .available in which data transfer information with

time stamp appears continuously.

At the end of data transfer result appears with performance parameters.

TOKEN PRIORITY:

The priority of the node also can be changed by using this option.


At any instant, one node can be disconnected from the shared medium.

And later whenever it is necessary, the node can be reconnected.


At any time, the simulation can be stopped and can be stopped and can be

continued. There is reset option in switch. The process will stop.


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TOKEN BUS OPERATION

Initially the IP address of the nodes and priority are given and nodes are

connected to the token bus network. Now token is passed between the nodes connected 2 to 4

nodes can be connected in the bus. As per the priority can be changed and then the token

passing will be take route as per the priority allotment.

During the file transfer suppose one node is the ring is connected then that node is

automatically disconnected and the token bus is refrontigned leaving that node automatically

no question is asked. The node can be reconnected using connect switch.


During the file transfer one node in the ring is disconnected, then that node is and

process will stop.

STORING OF TRANSFERRED FILES, RESULT AND TRACES:

For token operation, one directory namely token bus is created in the simulator

directory in C drive. For node 4, node 1, node 2, node3 and 4 subdirectories are

created.

Node can be sender or receiver when one file is transferred from one to another node.

The data file is stored in the destination node. Result is stored as file with the name

part is stored in excel format in which data can be used for graph.

There is a provision is every node store the trace window information in the

respective window. They are also stored in excel format.

PROCEDURE:


Select 2 nodes and carryout data transfer between two nodes simultaneously and

analyses. Repeat the experiment of different packet sizes and error.


analyses. Repeat the experiment changing the input parameter.

RESULT:

Thus the performance of token bus LAN protocol through simulation and

using trainer kit was verified successfully.


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VIVA QUESTIONS:

1. What is token ring?

Token ring local area network (LAN) technology is a local area

network protocol which resides at the data link layer (DLL) of the OSI model. It uses a

special three-byte frame called a token that travels around the ring. Token-possession grants

the possessor permission to transmit on the medium. Token ring frames travel completely

around the loop.

2.What is token bus?

Token bus is a network implementing the token ring protocol over a "virtual

ring" on a coaxial cable. A token is passed around the network nodes and only the node

possessing the token may transmit. If a node doesn't have anything to send, the token is

passed on to the next node on the virtual ring. Each node must know the address of its

neighbour in the ring, so a special protocol is needed to notify the other nodes of connections

to, and disconnections from, the ring.

3.Define networks.

A network is a set of devices connected by media links.

4. Define Communication channels

The links connecting the devices are often called communication channel.

5.What is meant by distributed processing & write any two advantages.

Networks use distributed processing in which a task is divided among

multiple computers.

Advantages: Security, Faster problem sloving, Collaborative processing

http://en.wikipedia.org/wiki/Local_area_network

http://en.wikipedia.org/wiki/Network_protocol

http://en.wikipedia.org/wiki/Data_link_layer

http://en.wikipedia.org/wiki/OSI_model

http://en.wikipedia.org/wiki/Token_ring

http://en.wikipedia.org/wiki/Coaxial_cable


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Exercise Number : 3

Title of the Exercise :WIRELESS LAN PROTOCOL



To create scenario and study the performance of wireless LAN protocol through

simulation and verify using LAN trainer kit.



1. PC - -



INPUT PARAMETERS:

No of Nodes - 2 to 4

Frame Interval - 250ms to 1000ms

Frame size - 128bytes to 1500bytes

Max. back off time - 4 to 32

Error generation - 0.01,0.1 and 1.5

TRANSFERRING A DATA FILE FROM ONE NODE TO ANOTHER: Each node is numbered as 1, 2, 3 and 4.

Each node is identified with its own input address.

From any node mode file from the system can be opened for transmission.

The file can be sent to any destination mode

At the time of sending , sender window and receiver window are opened in the

respective modes and data transfer occur

The progress bar in these windows shows the amount of data transferred and

received.

In each node, one trace window is available in which data transfer information with

stamp appears continuously.

At the end of data transfer, result appears with performance parameters.

STORING OF TRANSFERRED FILES, RESULTS AND TRACES:

For the wireless LAN operation, one directory namely wireless is created in the

simulator directory in C drive. For node 4, node 1, node 2 and node 3 node 4 sub

directories are created.

Node can be sender or receiver when one file is transferred from one node to another

node. The data file is stored in destination node. Result is stored as file with the name

part is stored in sender mode.

The result file is stored in excel format from which data can be for graph.


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There is a provision in every node to store the trace window information is the

respective node. They are also stored in excel format.


At any instant one node can be disconnected from the shared medium. And later

whenever it necessary the node can be reconnected.


At any time, the simulation can be stopped and can be continued there is reset

option in which the process will stop.

PROCEDURE:


Select 2 nodes and carryout data transfer between two nodes simultaneously and

analyze. Repeat the experiment for packet sizes. Different maximum back off time

and different error generation.


analyze. Repeat the experiment and changing the input parameter.

Select 4 nodes and do the data transfer when the transfer is going on. Disconnect one

node and observe and record the effect.

RESULT:

Thus the performance of wireless LAN protocol through simulation

and using trainer kit was verified successfully.


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VIVA QUESTIONS:

1.What is wireless LAN protocol?

IEEE 802.11 is a set of standards for implementing wireless local area network (WLAN)

computer communication in the 2.4, 3.6 and 5 GHz frequency bands. They are created and

maintained by theIEEE LAN/MAN Standards Committee (IEEE 802). The base version of

the standard IEEE 802.11-2007 has had subsequent amendments. These standards provide

the basis for wireless network products using the Wi-Fi brand name.

2.What is meant by Collaborative processing?

Both multiple computer and multiple users may interact on a task.

3.What are the factors that depends on the performance of a network criteria?

Performance of a network depends on a number of factors,

a. Number of users b.Type of transmission medium

b. Capabilities of the connected hardware d.Efficiency of software

4. Write the application which we are used in data communication?

i. Marketing &Sales ii. Financial services

iii.Cellular telephone ivCable television

5.Define protocol.

Protocol is a set of rules that govern data communication.

http://en.wikipedia.org/wiki/Wireless_LAN

http://en.wikipedia.org/wiki/Institute_of_Electrical_and_Electronics_Engineers

http://en.wikipedia.org/wiki/Local_area_network

http://en.wikipedia.org/wiki/Metropolitan_area_network

http://en.wikipedia.org/wiki/IEEE_802

http://en.wikipedia.org/wiki/Wi-Fi


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Exercise Number : 4

Title of the Exercise : STOP AND WAIT ARQ PROTOCOL



To implement and study the performance of stop and wait protocol through

simulation and LAN trainer kit.

FACILITIES REQUIRED AND PROCEDURE

a) FACILITIES REQUIRED TO DO THE EXPERIMENT:


1. PC - -



INPUT PARAMETERS

Packet size : 512B to 2048B

Round trip time:50ms to 150ms

Less Rate : 0% to 50%

Retransmit time out : 100ms to 1000ms.

NOTE

At the time of giving input parameters it is to be noted that output value given for

retransmit time out parameter should be more than RIT.

TRANSFERING DATA FILE FROM ONE SYSTEM TO ANOTHER SYSTEM

MAINLY in-WAN

In this experiement, there is one sender and one receiver.From the sender file the

system can be opened for transmission.

This can be send to the receiver by using start button .In between there is a

networks.There are trace windows in sender network and receiver and data through

information with the time stamp appears continuously.In networks the error information is

displayed.

At the end of the data transfer result appears with the performance parameters in the

bottom of the page namely payload, transform time throughput and losses.

STORING OF TRANSFERRED FILES AND TRACES.

At any time, the simulation can be stopped and can be continued, reset can be used to

start from the beginning.


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EXPERIEMNT TO BE CARRIED OUT:

Select a file from the system and transfer the file from sender or receiver .Assign the

following input parameters the data flow follows stop and wait algorithm in sending the

packets (frames) in the network.

Packet size 1024B

RTT 100ms

Loss rate 10%

Retransmission time out 200ms

Choose a file and send note down the results.Note down the trace,when packet error

has occurred and when the time out has triggered and what was the next action.Check

whether stop and wait algorithm is followed.

Change the packet size of 2048 bytes

Send the same file

Note down the results.

Compare the results.

Similarly change the loss rate and compare the result.

QUEING THE GRAPH AND PRINTING THE GRAPH

In order to view the frame sent time graph.First we have to loss the simulator

software.In C: drive inside the simulator directory in stop and wait directory .The graph is

stored as excel file.In the computer system excel software should be available to view the

graph by opening the file “ Time frame” .The graph can be seen and data instead, derived

from the trace can be seen.The graph can be printed in excel software .During the time out

the packet is resent. It can be clearly viewed in the graph.

PERFORMANCE

Payload delivered 124.416 Kbytes

Simulation time 207.53ms

Throughput 4.8723kbps

Good Put 4.7961 kbps

Data frame 122

RESULT:

Thus the performance of stop and wait protocol through simulation and LAN trainer

kit was verified successfully.


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VIVA QUESTIONS:

1. What is stop and wait ARQ protocol?

Stop-and-wait ARQ is a method used in telecommunications to send information

between two connected devices. It ensures that information is not lost due to dropped packets

and that packets are received in the correct order. It is the simplest kind of automatic repeat-

request (ARQ) method. A stop-and-wait ARQ sender sends one frame at a time; it is a

special case of the general sliding window protocol with both transmit and receive window

sizes equal to 1. After sending each frame, the sender doesn't send any further frames until it

receives an acknowledgement (ACK) signal. After receiving a good frame, the receiver sends

an ACK. If the ACK does not reach the sender before a certain time, known as the timeout,

the sender sends the same frame again.

2. In which layer error detection & error correction find?

Data can be corrupted during transmission. Transmission errors detected at

physical layer of OSI model. Transmission errors corrected at the data link layer.

3. Write the types of error & define it.

There are two types of error

a. single bit error

only one bit in the data unit such as a byte, character , or packet

changed from 1 to 0 or from 0 to1.

b. burst error

A burst error means that two or more bits in the data unit has

changed from 1 to 0 or 0 to1.

4. Define data link layer.

Data link layer is the second layer in OSI model. The DLL lies between the

network layer & physical layer. It receives services from physical layer and provides

services to the network layer. The DLL is responsible for carrying a packet from one

hop to next hop.

5. List out the duties of DLL?

Duties of DLL are

Packet zing,Addressing,Error control,Flow control, Medium access control

http://en.wikipedia.org/wiki/Telecommunications

http://en.wikipedia.org/wiki/Automatic_repeat-request


http://en.wikipedia.org/wiki/Frame_(telecommunications)

http://en.wikipedia.org/wiki/Sliding_window_protocol

http://en.wikipedia.org/wiki/Acknowledgement_(data_networks)


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Title of the Exercise : SELECTIVE REJECT ARQ PROTOCOL



To implement and study the performance of selective ARQ protocol using

simulation and LAN trainer Kit.




1. PC - -



INPUT PARAMETERS

Window size :1 to 10 packets

Bandwidth : 5000 kbs to 5000kbps

Frame size : 512B to 2048B

Round trip time :50ms to 500ms

Less Rate : 0% to 50%


TRANSFERING A FILE (DATA) FROM ONE NODE TO ANOTHER NODE

In this experiment, there is one sender and one receiver from the sender file the


This file can be send to the receiver by using start button .In between there is a

networks.There are trace windows in sender network and receiver and data through

information with the time stamp appears continuously. In networks the error information is

displayed.

At the end of the data transfer result appears with the performance parameters


The selective repeat simulator creates a directory named “selective repeat” in the

simulator directory in C: drive. The transmit file is stored in the directory.

PAUSE AND RESET FACILITY

At any time the simulation can be stopped and can be continued .Reset can be used to


PROCEDURE

Select a file the system and transfer the file from sender to receiver.Assign the

following input parameters.As the data flow follows selective repeat algorithm in sending the

packet (frames) in the network.


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Packet size 1024B

RTT 100ms

Less rate 10%


Window size :2000kbps

Bandwidth : 5 Packets

Choose a file and send data down the results.Note down from the trace, when packet error

has occurred and when the time out has stopped happened and what was the next

action.Check whether it follows the selective repeat algorithm


Send the frame file

Note down the results.

Compare the results.

Similarly change the loss rate and compare the result.Give the reason for congestion packet

drop.

VIEWING THE GRAPH AND PRINTING THE GRAPH

In order to view the frame sent Vs time graph.First we have to close the simulator

software.In C: drive inside the simulator directory in the selective repeat directory .The

graph is stored as excel file.In the computer system excel software should be available to

view the graph by opening the file “ Time frame xls” .The graph can be seen and data

derived from the trace can be seen.The graph can be printed in excel software .During the

time out, the packet is resent according to the Go-back –n algorithm in the graph.

By reducing the BW and by increasing the window size we will be able to see

congestion packet drop also in the network.

PERFORMANCE




Good Put 20.5214kbps

Data frame 130

RESULT:

Thus the performance of selective ARQ protocol using simulation and LAN trainer

Kit was verified successfully.


22


Title of the Exercise : GO BACK N ARQ PROTOCOL Date of the Exercise :


To implement and study the performance of Go Back N ARQ protocol using

simulation and LAN trainer Kit.




1. PC - -



INPUT PARAMETERS

Window size :1 to 10 packets

Bandwidth : 500 kbs to 5ms

Packet size : 512B to 2048B

Round trip time :50ms to 500ms

Loss Rate : 0% to 50%


TRANSFERING DATA FILE FROM ONE SYSTEM TO ANOTHER SYSTEM

MAINLY in-WAN

In this experiment, there is one sender and one receiver from the sender file from the


This file can be send to the receiver by using start button .In between there is a

network of networks.

If the time of sending sender window and receiver window are opened. The

progresses are in these windows shows amount of data transferred and received.

There are trace windows in sender network and receiver network and the data

transform information with the time stamp progress continuously

At the end of the data transfer result appears with the performance parameters.


The Go Back ON simulator creates a directory named “GO-BACK-N ” in the

simulator directory in C: drive. The transmit file is stored in this directory.


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PAUSE AND RESET FACILITY

At any time the simulation can be stopped and can be continued .Reset can be used to


PROCEDURE

Select a file from the system and transfer the file from sender to receiver. Assign the

following input parameters. As the data flow follows Go-Back-N wait algorithm in sending

the packet (frames) in the network.

Packet size 1024B

RTT 100ms


Window size :2000kbytes

Bandwidth : 5 Packets

Choose a file and send data down the results. Note down from the trace, when packet error

has occurred and when the time out has stopped happened and what was the next action.

Check whether it follows the Go-Back –N algorithm


Send the same file

Note down the result.

Compare the result.

Similarly change the loss rate Vs and compare the result..

VIEWING THE GRAPH AND PRINTING THE GRAPH

In order to view the frame sent Vs time graph. First we have to close the simulator

software. In C: drive inside the simulator directory in the Go-Back-N directory .The graph

is stored as excel file. In the computer system excel software should be available to view the

graph by opening the file “ Time frame xsl” .The graph can be seen and data derived from

the trace can be seen. The graph can be printed in excel software .During the time out, the

packet are used according to the Go-back –n algorithm. It can be clearly viewed in the graph.

By reducing the BW and by increasing the window size we will be able to see

congestion packet drop also in the network.

PERFORMANCE

Packet size 1024 bytes

Retransmit time 200ms

Window size 5 packets




Good Put 18.675kbps

Data frame 130

RESULT:

Thus the performance of Go Back N ARQ protocol using simulation and LAN

trainer Kit was verified successfully.


24

VIVA QUESTIONS:

1. What is selective reject ARQ protocol..

Selective Repeat ARQ / Selective Reject ARQ is a specific instance of

the Automatic Repeat-Request (ARQ) protocol used for communications. It may be

used as a protocol for the delivery and acknowledgement of message units, or it may

be used as a protocol for the delivery of subdivided message sub-units.

2. What is Go back N ARQ protocol..

Go-Back-N ARQ is a specific instance of the automatic repeat request (ARQ)

protocol, in which the sending process continues to send a number of frames specified by

a window size even without receiving an acknowledgement (ACK) packet from the receiver.

It is a special case of the general sliding window protocol with the transmit window size of N

and receive window size of 1.

3.Define parity bit.

The simplest form of error detection is to append a single bit called a parity bit

to a string of data.

4.Define hamming distance.

The number of bits positions in which two codeword differ is called the

hamming distance.

5.What is meant by codeword & block length?

Codeword is the encoded block of ‘n’ bits. It contains message bits and

redundant bits.

Block length: the number of bits ‘n’ after coding is called the block length of

the code.


http://en.wikipedia.org/wiki/Automatic_repeat_request

http://en.wikipedia.org/wiki/Data_frame

http://en.wikipedia.org/wiki/Acknowledgement_(data_networks)

http://en.wikipedia.org/wiki/Sliding_window_protocol


25

Exercise Number : 6

Title of the Exercise : ROUTING ALGORITHM’S /

DISTANCE VECTOR ALGORITHM



To Implement and study the distance algorithm



1. PC - -



INPUT PARAMETERS:

Router : 3 to 7

Connectivity between the routers to be given

Weight uncost

Some router to be selected

PROCESS:

The distance vector algorithm is executed initially in Iteration-1, the source router

creates the router table with the distance information of the other router connected to the

neighboring routers.

By using next switch second iteration is done. In the second iteration ,it calculates the

shortest distance to the unconnected notes then the information gathered in the first iteration

and defines the routing table. If there are ‘n’ routers the n-1 iteration are required to get

shortest distance for all the routers.

The routing table gives us shortest distance for all the routers from the some rout ion

and also information to which router the packet should go next.

PROCEDURE:

Select say 5 routers and draw the connectivity .Input the distance between the routers.

Select source router study the iteration and routing table for each iteration check finally

whether the short distance is calculated and correct next.

Keep the layout as is change for distance between the routers, the creation and for

each operation study and check and verify the result at the end. Keep the layout as it is

change the source router and do the experiments verify the result at the end. Do the different

configuration and do iteration and verify the results.


26

STORING OF TRANSFERRED FILES AND TRACES: The distance vector simulator executes a directory named “Distance Vectors” in the

simulator directory in ‘E’ drive.

RESULT:

Thus the implementation and performance of distance vector algorithm was

verified successfully.


27

VIVA QUESTIONS:

1. What is Routing algorithm?

Routing is the process of selecting paths in a network along which to send

network traffic. Routing is performed for many kinds of networks, including

the telephone network (Circuit switching),electronic data networks (such as

the Internet), and transportation networks.

2.What is Distance vector routing algorithm? A distance-vector routing protocol is one of the two major classes of routing

protocols, the other major class being the link-state protocol. A distance-vector routing protocol requires that a router informs its neighbors of topology changes periodically.

Compared to link-state protocols, which require a router to inform all the nodes in a

network of topology changes, distance-vector routing protocols have less computational

complexity and message overhead.

3.Define parity bit.

The simplest form of error detection is to append a single bit called a parity bit

to a string of data.

4.Define hamming distance.

The number of bits positions in which two codeword differ is called the

hamming distance.

5.What is meant by codeword & block length?

Codeword is the encoded block of ‘n’ bits. It contains message bits and

redundant bits.

Block length: the number of bits ‘n’ after coding is called the block length of

the code.

http://en.wikipedia.org/wiki/PSTN

http://en.wikipedia.org/wiki/Circuit_switching

http://en.wikipedia.org/wiki/Computer_network

http://en.wikipedia.org/wiki/Internet

http://en.wikipedia.org/wiki/Transport_network

http://en.wikipedia.org/wiki/Routing_protocol

http://en.wikipedia.org/wiki/Routing_protocol

http://en.wikipedia.org/wiki/Link-state_protocol

http://en.wikipedia.org/wiki/Link-state_routing_protocol

http://en.wikipedia.org/wiki/Computational_complexity

http://en.wikipedia.org/wiki/Computational_complexity

http://en.wikipedia.org/w/index.php?title=Message_overhead&action=edit&redlink=1


28

Exercise Number : 7

Title of the Exercise : LINK STATE ALGORITHM



To implement and study the link state algorithm.



1. PC - -



INPUT PARAMETERSS:

Router : 3 to 7

Connectivity between the routers to be given

Weight uncost or distance between routers number 1 to 10

Source router to be selected.

PROCESS:

The link state algorithm is executed .There are parent group and transitive group.

Initially in iteration the source router is an parent group and all the directly connected routers

are in the transitive group and router table is created.

By using next switch 2nd Iteration is done .In what iteration the short distance

neighboring router is taken into parent group and the routers associated with the particular

router are placed in the transitive group and routing table is connected. In this way of there n

routers available. The n number of iteration is required to find the shortest distance in this

method.

Finally the routing table sizes the shortest distance for all routers from the source

routers and also information to which router the packet should go next.

PROCEDURE:

Select say to routers and draw the connectivity Input the distance between the routers

select some router study the iteration and routing table every time created.

Check finally whether the short distance is calculated and correct next best loop.

Keep the layout as it is change the distance vector between the routers.

Do the iteration and for each iteration study and check verify the result at the end

Do the different configuration and do iteration and verify the results.


29


The link state simulator creates a directory named “Link state” in the simulator

directory in ‘E’ drive.

RESULT: Thus the implementation and performance of link state vector algorithm was



30

VIVA QUESTIONS:

1. What is link state algorithm?

The basic concept of link-state routing is that every node constructs a map of

the connectivity to the network, in the form of a graph, showing which nodes are

connected to which other nodes. Each node then independently calculates the next

best logical path from it to every possible destination in the network. The collection

of best paths will then form the node's routing table.

2. List out the services provided by the network layer.

The network layer is responsible for the source-to-destination delivery of a packet

possibly across multiple networks specific responsibility of a network layer includes the

following.

a. logical addressing b.Routing.

3. What is a virtual circuit?

A logical circuit made between the sending and receiving computer. The

connection is made after both computers do handshaking. after the connection; all

packets follow the same route and arrive in sequence.

4. What are datagrams?

In datagram approach, each packet is treated independently from all others. Even

when one packet represents just a place of a multipacket transmission, the networks treat

if as though it existed alone. Packets in this technology are referred to as datagrams.

http://en.wikipedia.org/wiki/Graph_theory

http://en.wikipedia.org/wiki/Routing_table


31


Title of the Exercise : DATA ENCRYPTION AND DECRYPTION SHIFTING

ALGORITHM



To implement the data encryption and decryption.



1. PC - -



INPUT PARAMETERS: Input font to be given.

Shift –no. of bits to be given.

PROCESS:

The shifting algorithm is executed at the time of encryption.

At the time of decryption, again shifting algorithm is executed.

PROCEDURE: Enter the font is the text box available.

Give the Shifting index and use shift key.

Encryption message appears in the window.

When re-shift key is used re-shift algorithm is used with encrypted message and re-

shifted message is displayed.

RESULT: Thus the performance of data encryption and decryption was verified successfully.


32


Title of the Exercise : RSA ALGORITHM



To implement the data encryption and decryption process during RSA algorithm

using simulation.



1. PC - -



INPUT PARAMETERS:

Initially a plain font of max to characters is given.

PROCESS:

Here the RSA algorithm is used for encryption and decryption.

PROCEDURE:

Encryption:

Encryption in key is used in the menu box.

Then again encryption key below the font window is used to encrypting the message.

RSA algorithm procedure is stage by stage executed and the steps are shown in the

output window.

Secret key and public key are generated and displayed.

Decryption:

Decryption key is used in the menu box.

then again decryption key below the font window is used to decrypting the message

Decryption stage is executed and steps are shown in the output window

The decrypted font is displayed.

RESULT:

Thus the performance of data encryption and decryption using RSA algorithm was



33

VIVA QUESTIONS:

1. What is meant by congestion?

Congestion in a network occurs if user sends data into the network at a rate

greater than that allowed by network resources.

2. Why the congestion occur in a network?

Congestion occurs because the switches in a network have a limited buffer

size to store arrived packets before processing.

3. What is data encryption ?

Data encryption refers to mathematical calculations and algorithmic schemes

that transform plaintext into cyphertext, a form that is non-readable to unauthorized

parties. The recipient of an encrypted message uses a key which triggers the algorithm

mechanism to decrypt the data, transforming it to the original plaintext version.

4.What is RSA algorithm?

An public-key encryption technology developed by RSA Data Security, Inc.

The acronym stands for Rivest, Shamir, and Adelman, the inventors of the technique.

The RSA algorithm is based on the fact that there is no efficient way to factor very

large numbers. Deducing an RSA key, therefore, requires an extraordinary amount of

computer processing power and time.The RSA algorithm has become the de facto

standard for industrial-strengthencryption, especially for data sent over the Internet.

5. What is the function of FECN?

The FECN bit is used to warn the receiver of congestion in the network. The

sender and receiver are communication with each other and are using some type of flow

control at a higher level.

http://www.webopedia.com/TERM/P/public_key_cryptography.html

http://www.webopedia.com/TERM/A/algorithm.html

http://www.webopedia.com/TERM/D/de_facto_standard.html

http://www.webopedia.com/TERM/D/de_facto_standard.html

http://www.webopedia.com/TERM/E/encryption.html

http://www.webopedia.com/TERM/I/Internet.html


34


Title of the Exercise :PC TO PC FILE TRANSFER PROTOCOL HTTP WEB

BROWSING



The function part IP is so for web browsing in this experiment the user can access one

control file the web server.



1. PC - 2


INPUT PARAMETERS:

Client ID –IP address

Server ID- IP address

PROCESS:

In the experiment at the time of connecting the client to the server communication

pipe namely socket is created. The socket is characterized by 4 parameters.

1. Server IP

2. Client IP

3. Local port number 80

4. Remote port number.

When the client sends the connect request to the server, it generates a 16 bit random and

send it as port no.

As for as the server is connected this port no. is remote port no. Once the socket is

created , the client can send the request to the server and set the file log is created in the

server.

PROCEDURE:

The client IP address is entered.

Then the server address is entered and activated.

Then in the client side , to connect to the server address is entered and the connect

switch is used to connect the client to the server.

Now the socket is created and the connection is made and log is given in the server.

Then the user can send the request to the server by typing #netline.com / index.html

and press go button.

How the request gives to server responds .It access the file namely index.html file and

transfer it to the client .Then the client hypertext made up language ,file and units.

There is an interaction between the server and the client the server sends the file to

the client and in the client window, the context of the file is displayed.


35

There is an interaction between the server and the client the server sends the file to

the client and in the client window, the context of the file is displayed.

The user can disconnect the client and server also. In the server side log is generated

to every activity.

The simulation is reused. In the simulation directory in C: drive the html file is

opened. In notepad and the content is altered and saved.

Again the same application is run.

It is to be verified that the modified context is appearing in the client window

RESULT:

Thus the function of PC to PC file transfer protocol HTTP web browsing was



36


Title of the Exercise : FTP –FILE TRANSFER PROTOCOL.



The function port ID is 21 for file transfer in this experiment, the user can do still

transfer from a FTP server.



1. PC - -


INPUT PARAMETERS:

Client ID–IP address


PROCESS:

In the experiment at the time of connecting the client to the server (It generally)

communication pipe namely socket is created. The socket is characterized by 4 parameters.

1. Server IP

2. Client IP



When the client sends the connect request to the server, it generates a 16 bit random which

lies between 1024 and 65.536 and send it as port no.

As for as the server is connected this port no. is remote port no.

In the FTP operation ,2 sockets are generated .They are control socket and data sockets.

Once the socket is created , the client can send the request to the server and set the file log is

created in the server.

RESULT:

Thus the performance of File transfer protocol was verified successfully.


37

Exercise Number : 9.c

Title of the Exercise : STOP E-MAIL



The function port Id is 25 for the file transfer .In this experiment, the user can send e-

mail to another

FACILITIES REQUIRED AND PROCEDURE FACILITIES REQUIRED TO DO THE EXPERIMENT:


1. PC - -


INPUT PARAMETERS:

Client ID–IP address


PROCESS:

In the experiment at the time of connecting the client to the server (It generally)

communication pipe namely socket is created. The socket is characterized by 4 parameters.

1. Server IP

2. Client IP



When the client sends the connect request to the server, it generates a 16 bit random which

lies between 1024 and 65.536 and send it as port no.

As for as the server is connected this port no. is remote port no.

In the e-mail operation 2 socket are generated. They are control socket and data socket.

Once the socket is created, the client can send the request to the server and set the file

log is created in the server and get the file.

PROCEDURE:

user is supposed to given client IP address and server address in server. Then in

the client configuration window. The server address is address to be given and

connect button is to be used.

Now the control socket and data socket are created.

Then the user can send the request to the server by typing [email protected]

and progress go button.

The content in the client window is taken as the message for the mail.

The mail reaches the mail box of the user.

The user IP address 132.168.11 can check email by using check mail key.

mailto:[email protected]


38

Then the user systems interact with the server and of there any mail it gives as

message that user has got a mail.

The content of the mail is also displayed in the user window.

RESULT:

Thus the performance of stop E-mail was verified successfully.


39

VIVA QUESTIONS:

1. Define FTP.

File transfer protocol is the standard mechanism provided by the TCP/IP for

copying a file one host to another. Transferring files from one computer to another is one of

the most common takes expected from a networking or internetworking environment.

2. How does FTP differ from other client server applications?

FTP differs from other client server applications in that it establishes two

connections between the hosts. One connection is used for data transfer and other for

control information.

3. What is SMTP?

The TCP/IP protocol supports electronic mail on the internet is called Simple mail

transfer protocol. It is a system for sending messages to other computer users based on e-

mail addresses.

4.What is Http?

The Hypertext Transfer Protocol is a protocol used mainly to access data on the

World Wide Web. The protocol transfer data in the form of plaintext, hypertext, audio,

and video and so on.

5.How does HTTP differ from SMTP?

a. HTTP differs from SMTP in the way the messages are sent from the client to

the server and from the server to the client.

b. Unlike SMTP, the HTTP messages are not destined to be read by humans.

c. HTTP messages are delivered immediately.

6. Relate HTTP and FTP.

HTTP is similar to FTP, because it transfers files and uses the services of TCP.

However it is much simpler than FTP, because HTTP uses only one TCP connection.

There is not a separate control connection.


40


Title of the Exercise :PC-PC COMMUNICATAION (PARALLEL)



The main aim of the experiement is to enough transfer a file from PC to another PC

using parallel port.



1. PC - 2


3. Parallel trainer kit - 2

DESCRIPTION

The main aim of the experiement is to transfer a file from PC to another PC using

parallel port.The interface between the PC’s is done through the parallel port(Lpt) in the PC,

a male to male a 25 pin D-type connection is used to connect together.The parallel port is

configure to run in bi-directional mode.The data links D0-D8 are used to readline a type of

data.The connect line STROBE and status link.ACK make the handshaking signal.The

Digital data pin are connected directly to the 74LS244 bidirectional buffer..The output of the

buffer is connected to the datalines of the parallel port.

OPERATION

The data bytes to the transmitted is placed on the data register(0*378)

The control PIN STORE is made low to indicate a valid data on the data bus.

The receiver PC wait for the status pin FCK to go high.

Once the ACK pin goes high the data in the data register is read.

The receiver PC then acknowledges by giving a pulse can be set by user.

This Handshaking sequence is repeated for every byte until the end of the life.


41

PROCEDURE

Connect one end of the 25Pin n-type male and male connector to the parallel port of

your PC (LPT) signal.

Connect end to be 25 pin n-type female connector of the PC to PC communication.

Repeat the step1 and step2 with order.

Connect the STROBE pin of system 1 to the ACK pin of System 2 in the trainer kit.

Connect datapins D0-D7 of System1 to pins D0-D7 System2.

Common the ground terminals

Run Parallel 1 in both the PCs.

PC TRANSMITTING SYSTEM:

Select the file to be sent in the PC from which you want to transfer file.

FOR RECEIVING SYSTEM

Set the transmission rate.The user can choose the present rate it “Choose Delay”

option is selected or can assign only rate from 1 to 100ns it “ user Delay “ option is selected.

Select the path for the file to be stored.

NOTE:

The “reactive file “ or “receive files” button is disable control the file path for the

receiving file is selected.

Click “ Send file” button is the transmitting PC.

Clock “ Receive file” Button in the receiver PC.

“File through transfer Completer” message appears both in the transmitter and

receiver PC once the transfer is complete.

The file is complete will be displayed on the textbook in the receiver PC.

Clock “ Clear “ button to clear the contents in the text Box.

Repeat all the above steps to send a new file.

RESULT:

Thus the performance of transfer a file from PC to another PC using parallel

port was verified successfully.


42


Title of the Exercise : PC-PC COMMUNICATAION (SERIAL)



The main aim of the experiment is to enough transfer a file from PC to another PC

using Serial port.



1. PC - 2


3. Parallel trainer kit - 2

PROCEDURE

Connect one end of the Pin n-type female to female connector to the serial port of

your PC signal.

Connect other end to the 9 pin n-type for female connector of the PC to PC

communication trainer.

Repeat the step1 and step2 with other PC system2.

Connect RXD pin of System1 to find pin of System 2

Connect RXD pin of System2 to TXD pin of System 1

Connect MXR pin of System2 to NSR pin of System 2

Connect RTS pin of System1 to MS pin of System 2

Connect RTS pin of System2 to MS pin of System 1

Common the ground terminals

Run Serial 1 in both the PCs.

Select the common terminal and Band rate.


43

NOTE:

Band rate selected should be same for both the PCs

Click set “ Serial-port” button successively change message appears.

The status of the CTS pin will read ‘nodal ‘ in both receiver and transmitter.

Clock RTS button in the transmitting Pc and receiver Pc.

The status of the CTS pin will read ‘ok’ in both receiver an transmitter.

The status of the ASR pin will read ‘ok’ in both receiver an transmitter.

Type the message to be transmitted in the text box.

Click “ Transmit” button to transmit in the typed context.

Click “ CLR SCREEN” button to clear the text box.

TO TRANSMIT A FILE

Type the message in the text box.

Type the file Port with name to which context to be written.

Click the “ WRITE-SCREEN-TO – FILE” button to the write context.

Click the “ READ-FILE-TO-SCREEN” button to read context of the file.

Clock “ Transmit – file “ button to transmit in the context.

NOTE

The tranmitted file content will be stored in the path given in the receiving PC.

Click “ CLR –SCREEN “to repeat the process.

Click “ STOP “ button to exit.

RESULT:

Thus the performance of transfer a file from PC to another PC using serial

port was verified successfully.


44

VIVA QUESTIONS:

1. What is parallel communication?

parallel communication is a method of sending several data signals simultaneously

over several parallel channels. It contrasts with serial communication; this distinction is one

way of characterizing a communications link.

2. What is serial communication?

serial communication is the process of sending data one bit at a time, sequentially,

over a communication channel or computer bus. This is in contrast to parallel

communication, where several bits are sent as a whole, on a link with several parallel

channels. Serial communication is used for all long-haul communication and most computer

networks, where the cost of cable and synchronization difficulties make parallel

communication impractical.

3. Define DNS?

System that can map a name to an address and conversely an address to a name.

In TCP/IP, this is the domain name system.

4. Name different sections used in internet DNS.

a. Generic domain b. Country domain c. Inverse domain

5. What does a generic domain define?

The generic domains define registered hosts according to their generic behaviour.

6. Mentions the usage of inverse domain.

a. Inverse domain is used to map an address to a name.

b. To determine if the client is on the authorized list , it can send a query to the

DNS server and ask for the mapping of address to name.

http://en.wikipedia.org/wiki/Serial_communication

http://en.wikipedia.org/wiki/Data

http://en.wikipedia.org/wiki/Bit

http://en.wikipedia.org/wiki/Communication_channel

http://en.wikipedia.org/wiki/Computer_bus

http://en.wikipedia.org/wiki/Parallel_communication

http://en.wikipedia.org/wiki/Parallel_communication



http://en.wikipedia.org/wiki/Cable

http://en.wikipedia.org/wiki/Synchronization


45

QUESTION BANK

1. Implement PC to PC Communication for

(i)Parallel Communication using 8 bit parallel cable

(ii)Serial communication using RS 232C

2. Create scenario and show the performance of CSMA/CD protocol

through simulation using Ethernet LAN protocol.

3. Create scenario and show the performance of CSMA/CD protocol

through LAN Trainer Kit using Ethernet LAN protocol.

4. Create scenario and show the performance of token bus and token ring

protocols through simulation

5. Create scenario and show the performance of token bus and token ring

protocols through LAN Trainer kit

6. Create scenario and show the performance of network with CSMA / CA

protocol and compare with CSMA/CD protocols using Wireless LAN

protocols.

7. Implement and show the stop and wait protocol using simulation.

8. Implement and show the Goback-N and selective reject protocols.

9. Implement the distance vector routing algorithm to determine the shortest

path between two nodes.

10. Implement the Link state routing algorithm using simulation.

11. Implement the Data encryption and decryption using RSA algorithm

through simulation.

12. Transfer the files from PC to PC using SMTP.

13. Transfer the files from PC to PC using HTTP. 14. Transfer the files from PC to PC using FTP.

Documents

EC2356 - COMPUTER NETWORKS LABORATORY LABORATORY MANUAL ... LAB MANUAL.pdf · EC2356 - COMPUTER NETWORKS LABORATORY LABORATORY MANUAL ... the answer to the viva-voce questions