DDOS can't really be stopped quickly no matter what arbor says at this time as each point must be stopped one at a time. Also, that is most likely the ISP's domain as they are the ones with the routers and therefor you are at thier mercy.
Do you have to guarantee connection latency or just uptime. These are 2 very different things. DDOS is in reality an SLA problem and has nothing to do with five 9's in my eyes.
