public   static   boolean  compareIpsMask(String ip1, String ip2,  int  rang)
	{
		 try {
			 int  mask = 0xffffffff;
			 for ( int  y= 0 ;y<( 32 -rang);y++) mask<<= 1 ;
			 long  iaddr =  0 ;
			 long  iraddr =  0 ;
			StringTokenizer st =  new  StringTokenizer(ip1,".", false);
			 for ( int  y= 0 ;st.hasMoreTokens();y++){
				iaddr<<=y* 8 ;
				iaddr|=Integer.parseInt(st.nextToken());
			}
			st =  new  StringTokenizer(ip2,".", false);
			 for ( int  y= 0 ;st.hasMoreTokens();y++){
				iraddr<<=y* 8 ;
				iraddr|=Integer.parseInt(st.nextToken());
			}
			 return  ((iaddr&mask)==(iraddr&mask));
		} catch (Exception e){
			 return  false;
		}
	}