BoardCastSer.Py:

#!/usr/bin/python
# -*- coding: utf-8 -*-

import socket,traceback

host = ''
port = 12345

s = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
s.setsockopt(socket.SOL_SOCKET,socket.SO_BROADCAST,1)
s.bind((host,port))
print "Listen on the port 12345......"
while True:
    try:
        sock,addr = s.recvfrom(8192)
        print "Receive data from:",addr
        s.sendto("I'm here BOSS!",addr)
    except (KeyboardInterrupt,SystemExit):
        raise
    except:
        traceback.print_exc()
    

BoardCastCli.Py:

#!/usr/bin/python
# -*- coding: utf-8 -*-

import socket,sys
desc = ('<broadcast>',12345)
s = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET,socket.SO_BROADCAST,1)
s.sendto("Hello",desc)
print "Looking for replies........"
while True:
    sock,addr = s.recvfrom(2048)
    if not len(sock):
        break
    print "Received from %s:%s"%(sock,addr)