UDPPingerClient.py

# This is the UDP client program.
# This sends the message to the sever.
# This program calculates RTT of the different messages.
# It then prints the RTT of each request.
# If the waiting time is more than 1 second then the packet is considered lost and a time out is issued.

# Import socket module
# Import time and ctime to retrieve time
# Import sys to retrieve the arguments
from socket import *
from time import time, ctime
import sys

# Inputs three arguments.

if (len(sys.argv) != 3):
    print(len(sys.argv))
    print("Wrong number of arguments.")
    print("Use: UDPPingClient.py <server_host> <server_port>")
    sys.exit()

# Preparing the socket
serverHost, serverPort = sys.argv[1:]
clientSocket = socket(AF_INET, SOCK_DGRAM)
clientSocket.settimeout(1)

# Send and receive 10 requests.
for i in range(10):
    startTime = time() # Retrieve the current time
    message = "Ping " + str(i+1) + " " + ctime(startTime)[11:19]

    try:

        # Sending the message and waiting for the answer
        clientSocket.sendto(message.encode(),(serverHost, int(serverPort)))
        encodedModified, serverAddress = clientSocket.recvfrom(1024)

        # Checking the current time and if the server answered
        endTime = time()

        # Modified message is  decoded.
        modifiedMessage = encodedModified.decode()
        print(modifiedMessage)

        # Prints the RTT
        print("Round Trip Time: %.3f ms\n" % ((endTime - startTime)*1000))
    except:
        print("PING %i Request timed out\n" % (i+1))

clientSocket.close()