can stop this ???

VNC log, it seems attempt to enter my pc ???
or it's normal ???

15/3/2007 16:23   Invalid attempt from client 211.244.30.17
15/3/2007 16:24   Invalid attempt from client 200.168.142.234
15/3/2007 16:24   Invalid attempt from client 70.129.29.82
15/3/2007 16:25   Invalid attempt from client 61.63.166.124
15/3/2007 16:25   Invalid attempt from client 85.130.13.43
15/3/2007 16:26   Invalid attempt from client 190.72.193.27
15/3/2007 16:26   Invalid attempt from client 85.130.13.43
15/3/2007 16:26   Invalid attempt from client 68.127.234.22
16/3/2007 14:38   Invalid attempt from client 69.245.255.90
ic, thx!