Python Networking

Many python modules which give access to application layer networking services

• ftp
• http
• telnet

Sometimes you may have to implement your own application layer protocol. In this type of case you have to use sockets(a Transport Layer Service)

import sys
from socket import *
serverHost = ’localhost’
serverPort = 2000
# create a TCP socket
s = socket(AF_INET, SOCK_STREAM)
s.connect((serverHost, serverPort))
s.send(’Hello world’)
data = s.recv(1024)
print data

---

from socket import *
myHost = ’’
myPort = 2000
# create a TCP socket
s = socket(AF_INET, SOCK_STREAM)
# bind it to the server port number
s.bind((myHost, myPort))
# allow 5 pending connections
s.listen(5)
while 1:
# wait for next client to connect
connection, address = s.accept()
while 1:
data = connection.recv(1024)
if data:
connection.send(’echo -> ’ + data)
else:
break

connection.close()