hello again thanks for the earlier replys helped alot....anyway

running netstat -a on w2k and finding on my dos prompt´(besides some tcp and other UDp's)

Proto local address foreignaddress state
UDP 'usergroup:38037 *.*
UDP 'usergroup:isakmp' *.*


What does UDP that TCP does not and on such a high port number?
isakmp what is that??
What range on the port numbers listening are normal (I heard somepeople open backdoors on high portnumbers)?


New to security and networking,