SIMPLE COMMUNICATION USING UDP SERVER

AIM:
To write a python program for simple client-server using UDP.

PROCEDURE:
SERVER SIDE:

Step1:Create UDP[User Datagram Protocol] socket.

Step2:Specify the communication domain and type of socket to be created.

Step3:Bind the socket to the server address.

Step4:Wait until datagram packet arrives from client.

Step5:Process the datagram packet and send a reply to the client.

CLIENT SIDE:

Step1:Create UDP socket.

Step2:Encode the message to be sent in bytes.

Step3:Specify the communication domain and type.

Step4:Wait until response from server is received.

PROGRAM:
SERVER SIDE:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.bind(('127.0.0.1',7100))

data,addr=s.recvfrom(1024)

print(data)

CLIENT SIDE:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.sendto(str.encode("HII SERVER"),('127.0.0.1',7100))

OUTPUT:
SERVER SIDE:

>>>exec(open(“R:\\New folder\\server.py”).read())

B’HII SERVER’

CLIENT SIDE:

>>>exec(open(“R:\\New folder\\client.py”).read())

RESULT:
Thus the program for client-server using UDP is implemented.
 ECHO CLIENT SERVER IMPLEMENTATION USING UDP
AIM:
To write a python program for Echo client-server communication using UDP.

PROCEDURE:
SERVER SIDE:

Step1:Import socket module.

Step2:Create a datagram socket.

Step3:Bind the socket to the server id and port.

Step4:Wait until the datagram arrives from client.

Step5:Receive the data packets from the client along with its address.

Step6:Print the address and data

CLIENT SIDE:

Step1:Import socket module.

Step2:Create UDP socket.

Step3:Encode the message to be sent in bytes.

Step4:Send the data to server.

Step5:Receive the message.

Step6:Print the data and address received from server.

PROGRAM:
SERVER SIDE:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.bind(('127.0.0.1',6011))

print("server is waiting")

data,addr=s.recvfrom(1024)

print(data,addr)

s.sendto(data,addr)
CLIENT SIDE:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.sendto(str.encode("hii"),('127.0.0.1',6011))

data,addr=s.recvfrom(1024)

print(data,addr)

OUTPUT:
SERVER SIDE:

>>>exec(open(“R:\\New folder\\server.py”).read())

server is waiting

b’hii’(‘127.0.0.1’,49161)

CLIENT SIDE:

>>>exec(open(“R:\\New folder\\client.py”).read())

b’hii’(‘127.0.0.1’,6011)

RESULT:

Thus the program for Echo client-server communication using UDP is implemented.
 HALF DUPLEX COMMUNICATION USING TCP
AIM:
To write a python program for half duplex communication using TCP.

PROCEDURE:
SERVER SIDE:

Step1:Import socket module.

Step2:Create a TCP[Transmission Control Protocol]socket object for communication.

Step3:Bind the socket to the server.

Step4:Wait until connection is established between client and server.

Step5:Receive the data packets from client.

Step6:Send the reply to the client.

Step7.If the reply is disconnect, then the conncection will be closed.

CLIENT SIDE:

Step1:Import socket module.

Step2:Create a TCP socket object for communication.

Step3:Connect the socket to the server.

Step4:Send a message to the server.

Step5:Receive the message sent by server.

Step6:Print the message.

Step7:If the message is disconnect, then close the socket connection.

PROGRAM:
SERVER SIDE:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)

s.bind(('127.0.0.1',6012))

s.listen(1)

client,addr=s.accept()
while True:

data=client.recv(1024)

print(data)

sentence=input(">>")

client.send(str.encode(sentence))

if "quit" in str(sentence):

break

client.close()

CLIENT SIDE:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)

s.connect(('127.0.0.1',6012))

while True:

sen=input(">>")

s.send(str.encode(sen))

data=s.recv(1024)

print(data)

if "quit" in str(data):

break

OUTPUT:
SERVER SIDE:

>>>exec(open(“R:\\New folder\\server.py”).read())

b’hii’

>>hello

b’how are you’

>>fine

CLIENT SIDE:

>>>exec(open(“R:\\New folder\\client.py”).read())
>>hii

b’hello’

>>how are you

b’fine’

RESULT:
Thus the half duplex communication using TCP is implemented.
 FULL DUPLEX COMMUNICATION USING UDP
AIM:
To write a python program for full duplex communication.

PROCEDURE:

SERVER SIDE:

Step1:Import socket module.

Step2:Create a UDP socket object for communication.

Step3:Bind the socket to the server.

Step4:Create an array list of clients.

Step5:Connection will be established between client and server.

Step6:Communication between clients and the server will record the date and time transmitted
between clients.

CLIENT SIDE:

Step1:Import socket module and threading.

Step2:Create an UDP socket object for communication.

Step3:Establish connection between server and client.

Step4:Get data as input and send to server.

Step5:Server again retransmits the data to other clients connected to server using threading.

Step6:Print the data in clients, such that there is full duplex communication.

Step7:If the message is q, then client stops sending data to the server.

PROGRAM:
SERVER SIDE:

import socket

import time

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.bind(('127.0.0.1',7000))

clients=[]
s.setblocking(0)

quitting=False

while not quitting:

try:

data,addr=s.recvfrom(1024)

if 'q' in str(data):

quitting=True

if addr not in clients:

clients.append(addr)

print(time.ctime(time.time())+str(addr)+":"+str(data))

for client in clients:

s.sendto(data,client)

except:

pass

s.close()

CLIENT SIDE:

import socket

import time

import threading

shutdown=False

tlock=threading.Lock()

def receiving(name,sock):

while not shutdown:

tlock.acquire()

try:

while True:

data,addr=sock.recvfrom(1024)

print(data)
 except:

pass

finally:

tlock.release()

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.bind(('127.0.0.1',0))

s.setblocking(0)

rT=threading.Thread(target=receiving,args=("Recvthread",s))

rT.start()

alias=input("Name:")

ali=str.encode(alias+":")

message=input(alias+"->")

msg=str.encode(message)

while 'q' not in str(msg):

if "''" not in str(msg):

d=(ali+msg)

s.sendto(d,('127.0.0.1',7000))

tlock.acquire()

message=input(alias+"->")

msg=str.encode(message)

tlock.release()

shutdown=True

rT.join()

s.close()

OUTPUT:
SERVER SIDE:

>>>exec(open(“R:\\New folder\\server.py”).read())

Mon Dec 17 18:41:23 2018(‘127.0.0.1’,49168):b’janu:hii’

Mon Dec 17 18:41:32 2018(‘127.0.0.1’,49168):b’janu:Who is this?’

CLIENT SIDE:

>>>exec(open(“R:\\New folder\\client.py”).read())

Name:janu

Janu->hii

Janu->

b’janu:hii’

b’jansi:hello’

janu->who is this

>>>exec(open(“R:\\New folder\\client.py”).read())

Name:jansi

Jansi->

b’hii

jansi->hello

b’janu:hii’

b’jansi:hello’

b’janu:who is this?

RESULT:
Thus the full duplex communication is established.
 IMPLEMENTATION OF SIMPLE STOP AND WAIT PROTOCOL
AIM:
To write a python program to send and receive frame using Stop and Wait protocol.

PROCEDURE:
SENDER:

Step1:Import socket module.

Step2:Create a UDP socket object for communication.

Step3:Bind to the receiver.

Step4:Send a frame.

Step5:After transmitting one packet, the sender waits for an acknowledgement before transmitting next
one.

Step6:Close the socket after sending data.

RECEIVER:

Step1:Import socket module.

Step2:Create a UDP socket object for communication.

Step3:Bind the socket to loop back address.

Step4:Receive the frame.

Step5:After receiving, send the acknowledgement(ie.the next expecting frame).

Step6:Close the socket.

PROGRAM:

SENDER:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.bind(('127.0.0.1',6009))

while True:

data=input(">>")

s.sendto(str.encode(data),('127.0.0.1',6014))

m,a=s.recvfrom(1024)
 print("EXPECTING FRAME:"+str(m))

s.close()

RECEIVER:

import socket

s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)

s.bind(('127.0.0.1',6014))

count='0'

while True:

acknowledge=False

while not acknowledge:

ack,ad=s.recvfrom(1024)

print("FRAME RECEIVED:"+str(ack))

if "0" in str(ack):

count='1'

elif "1" in str(ack):

count='0'

else:

break

s.sendto(str.encode(count),ad)

acknowledge=True

s.close()

OUTPUT:
SENDER:

>>>exec(open(“R:\\New folder\\sender.py”).read())

>>1

EXPECTING FRAME:b’0’

>>0

EXPECTING FRAME:b’1’
>>1

RECEIVER:

>>>exec(open(“R:\\New folder\\sender.py”).read())

FRAME RECEIVED:b’1’

FRAME RECEIVED:b’0’

RESULT:
Thus the frame has been sent and received using stop and wait protocol.
 IMPLEMENTATION OF ARP PROTOCOL
AIM:
To write a python program to simulate Address Resolution Protocol.

PROCEDURE:
Step1:Create an array to store the IP and its corresponding MAC address.

Step2:Get the input address and MAC address as input.

Step3:Print the IP and MAC.

Step4:Search the MAC for your corresponding ip in the stored table.

Step5:Print the MAC address which is a hexadecimal number.

PROGRAM:
d={}

for i in range(2):

ip=input("Enter the ip:")

mac=input("Enter the mac:")

d[ip]=mac

print()

print(d)

s=input("Enter the search item:")

print(d[s])

OUTPUT:
>>>exec(open(“R:\\New folder\\arp.py”).read())

Enter the ip:10.1.24.121

Enter the mac:E0-CA-94-CB-A4-D8

Enter the ip:10.1.24.122

Enter the mac:E0-C7-94-CB-A4-D7

{’10.1.24.121’:’E0-CA-94-CB-A4-D8’,’10.1.24.122’:’E0-C7-94-CB-A4-D7’}

Enter the search item: 10.1.24.122

RESULT:
Thus the Address Resolution Protocol is simulated.
 FIND THE ADDRESS SPACE,FIRST ADDRESS,LAST ADDRESS USING
SUBNETTING IN CIDR
AIM:
To write a python program to calculate first address, last address and address space of given IP.

PROCEDURE:
Step1:Import ipaddress module and math module.

Step2:Get the IP address and prefix number.

Step3:Split the IP address and prefix number.

Step4:Find the Address space using the formula 2^(32-prefix number).

Step5:Using IPV4 network, list of all addresses from first to last are stored in array.

Step6:Print n[0] and n[-1] to get the first and last address.

PROGRAM:
import ipaddress

import math

ip=input("Enter the ip address:")

i=ip.split("/")

p=i[1]

l=32-int(p)

val=math.pow(2,int(l))

n=ipaddress.IPv4Network(ip)

first,last=n[1],n[-1]

print("ADDRESS BLOCK",int(val))

print("FIRST ADDRESS",first)

print("LAST ADDRESS",last)

OUTPUT:
>>>exec(open(“R:\\New folder\\subnet.py”).read())

Enter the ip address:10.1.24.0/26

FIRST ADDRESS 10.1.24.1

LAST ADDRESS 10.1.24.63

RESULT:
Thus the address space,last address and first addresses are calculated from the given ip.
 IMPLEMENTATION OF HTTP SOCKET
AIM:
To write a python program for webpage upload and download using http socket.

PROCEDURE:
UPLOADING:

Step1:Import HTTPServer and BaseHTTPRequest from http.server.

Step2:Create a class Serv.

Step3:Handle the HTTP requests that arrive at the server.

Step4:If specified path is ‘/’ the upload the html file.

Step5:Send response 200.

Step6:Else send response 404 and ‘FILE NOT FOUND’.

Step 7:Write the file content on the screen.

Step8:Close the HTTP server.

DOWNLOADING:

Step1:Import urllib.request module for fetching URLs.

Step2:Urllib.request.urlretrieve the files from the specified link.

PROGRAM:
UPLOADING:

from http.server import HTTPServer,BaseHTTPRequestHandler

class Serv(BaseHTTPRequestHandler):

def do_GET(self):

if self.path==(r'/'):

self.path=(r'C:/new\file.html')

try:

file_to_open=open(self.path[2:]).read()

self.send_response(200)

except:
 file_to_open="FILE ERROR"

self.send_response(404)

self.end_headers()

self.wfile.write(bytes(file_to_open,'utf-8'))

httpd=HTTPServer(('127.0.0.1',8000),Serv)

httpd.serve_forever()

HTML FILE:

<html>

<head>

<title>welcome</title>

</head>

<body>

<h3>WELCOME</h3>

</body>

</html>

DOWNLOADING:

import urllib.requesturllib.request.urlretrieve("https://www.govtrack.us/congress/votes/115-
2017/h200/diagram","angl.jpg")

OUTPUT:
UPLOAD:

>>>exec(open(“R:\\New folder\\upload.py”).read())
DOWNLOAD:

>>>exec(open(“R:\\New folder\\download.py”).read())

RESULT:
Thus the webpage upload and download are done using http socket.