Full Disclosure: I work for DiscountASP.NET
Yes, DiscountASP.NET was down for 2 days due to a massive DDoS attack back in June 2007. This is public knowledge and we are not ashamed in any way about it. There are many reasons why the downtime was for an extended period of time and we recap the entire episode in our Community Forum out in the open.
The attack was MASSIVE in scale - even the security team of our upstream provider (who hosts major search engines and major banks) could not believe the size of the attack and they could not even provide a timely solution to this attack. We even discussed diverting traffic to other Tier 1 Dedicated Hosting providers who claim to have excellent DDoS mitigation services and they all refused our business because they could not "handle" the traffic - and that is after their System Admins and Security experts kept repeating "Oh my God, Oh my God" when we described the attack. And let me just say that these dedicated hosting providers are the very same ones that many other windows hosts use for their infrastructure.
We did mitigate the DDoS attack and resolved the issue by partnering with Prolexic. This is the same company that HUGE ISPs, domain registrars, fortune 500 companies, major news sites, and even some foreign country governments use to protect themselves from massive DDoS attacks.
People like TOMCIO continue to bring up old news about the DDoS attack. I think that the ASP.NET forum users are a lot smarter than that. If we were truly a terrible host, we would have lost tons of customers after the DDoS attack. The exact opposite happenned and we continue to grow in new sales and keep our customers. Why? DiscountASP.NET has moved forward and our hosting platform is even more protected than was before.
So customers should consider DiscountASP.NET, if they want to have secure hosting. I would challenge any body that is considering the other hosts that other users have posted here to ask those providers about their security infrastructure and please let us all know about their results. We don't rely on our upstream provider or luck for our customer's security - we've proactively invested over 6-figures in a Tippingpoing Intrusion Prevention System and we continue to use Prolexic DDoS Mitigation services.
What do the other hosts do to protect their customers from similar DDoS attacks?