Im not sure what you are referring to. Are you and your brother playing computers in the same house/room ? What do you mean by 'logged on' ie. does this mean the 'internet' ?? If you both have computers in the same room/house you dont have to be logged on to anything, all you need to do is make sure your computers are "talking" by having created a network link between them. If you have XP, and a Lan cable, this is very easy to do. If this is what you're trying to do I know a bit about it ... I play MP this way all the time when I take my laptop over to friends' places....
If you and your brothers computers are not in the same house, it is trickier. You will need to establish a VPN(virtual private network), I think(??), so your computers are "talking" via the phone line. Ive never done that before, but Im sure it wouldnt be too hard with XP.... Maybe someone else can give you some more advice about that......
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