You must have a server edition of Windows in order for it to be a Domain controller. If you are seeking a cheaper alternative, I have two suggestions, one is that you find a copy NT Server which will be much cheaper than 2000/XP-the downside here is it will not use Active Directory but who cares if you just want to learn? The second is to use a linux machine with SAMBA as a domain controller, but again no AD. If you think you may want to use NT then PM me I have a NT Server 4.0 with license I dont use. L2TP and IPsec are not the same nor do they have to be used together. I've never used L2TP personally but from what I understand its a PPP tunneling protocol so unless you are using dial-up access or non TCP/IP stuff it may not really be what you need. I believe it is combined with IPsec to increase security as traditionally PPP connections are authenticated by a RADIUS server(CHAP,MSCHAP,all that stuff). IPsec uses IKE for a key exchange and ESP to encrypt and sign the data, so it can be used in conjunction with L2TP to tightly encrypt PPPtP traffic end to end, but again never used L2TP so dont quote me on that.


-Maestr0