@StefanS:
That may probably be correct in principle in such a way, however already differently saw.
We have at present a 2Mbit synchron connection, here had i already DoS.
From 2008 we will have 8Mibt synchron and i think that becomes with DoS not better.
It's the same whether you have 2 Mb or 8 Mb or 50 Mb. Every script kiddie on earth has enough bots under their control to DoS a connection of 50 Mb or less off of the Internet. Many have enough to DoS a 1 Gb connection or more.
In this type of scenario, your firewall, no matter what it is, can't help you. Your pipe coming from your ISP is overloaded, it doesn't matter what you do with the traffic once it gets to your end of the pipe, your connection is useless. Your ISP has to handle DoS attacks on their side of your connection so your connection isn't overloaded with the DoS traffic. There isn't anything you can do about it on your end, it's too late at that point.
Re: CA management, yes, eventually, though no work is currently happening in this area. If you start a bounty, it may get done faster.
Re: shaping with VPN, not possible at this time, but some changes are in the works that may allow this in a future release.
Re: mobile user, not sure on that one.