ping-pong tcp testing for network benchmark

client.py

import socket
import datetime
import sys
import time
def main():
    message = "Ping"
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.settimeout(120)
    if len(sys.argv) != 3:
      print "Correct usage: script, IP address, port number"
      exit()
    IP_address = str(sys.argv[1])
    Port = int(sys.argv[2])
    sock.connect((IP_address, Port))
    ctr = 300
    i = ctr
    rst = []
    while i > 0:
        time.sleep(1)
        #print('start...')
        try:
            begin_time = datetime.datetime.now()
            sock.send(message)
            while True:
                #print "waiting..."
                data = sock.recv(2048)
                if data == "Pong":
                    end_time = datetime.datetime.now()
                    print("recv at {}".format(end_time))
                    i = i - 1
                    break
                else:
                    print(data)
                    continue

        except socket.timeout:
            print "time out"
        else:
            msec = (end_time - begin_time).microseconds / 1000.0
            #print "rtt: %f msec" % msec
            rst.append(msec)
    print "avg rtt: %f msec, max rtt %f msec, min rtt %f msec at %d rounds" % (sum(rst)/len(rst), max(rst), min(rst),ctr)
    sock.close()
if __name__ == '__main__':
    main()

server.py

import socket
import sys

def serve_forever():


    server = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
    server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) 
  
    # checks whether sufficient arguments have been provided 
    if len(sys.argv) != 3: 
        print "Correct usage: script, IP address, port number"
        exit() 

    # takes the first argument from command prompt as IP address 
    IP_address = str(sys.argv[1]) 
  
    # takes second argument from command prompt as port number 
    Port = int(sys.argv[2]) 
  
    """ 
    binds the server to an entered IP address and at the 
    specified port number. 
    The client must be aware of these parameters 
    """
    server.bind((IP_address, Port)) 
    server.listen(1) 

    print "%s Serving on port %s ..." % (IP_address, Port)
    resp = "Wrong"
    while True:
        conn, addr = server.accept()
        print('Connected by', addr)
        conn.settimeout(10)
        while True:
            try:
                req = conn.recv(2048)                
                if req == "Ping":
                    resp = "Pong"
                conn.send(resp)
            except socket.timeout:
                pass
            if not req:
                print 'Connection lost. Listening for a new controller.' 
                break
            #Timeout occurred, do things
    conn.close()

if __name__ == '__main__':
    serve_forever()