Code:
import socket 
from socket import gaierror,herror 
ip='192.168.0.' 
name={ ##name resolver 'Dhir':'Dhiraj PC'## } 
for i in range(100,110): 
    add=ip+str(i) 
    try: 
        up=socket.gethostbyaddr(add)[0] 
        if(name.has_key(up)): 
            print add+'--{'+name.get(up)+'} is up!' 
        else :  
            print up+' is up!' 
    except herror: 
        pass
This is my code...is there any way to make it fast....i can tolerate 3 sec delay but not more than 5 second when checking for every node..