DDOS attack mitigation is itself the area, I think you should better read about various mitigation methods available currently and study their limitations and think about how you can come over limitations. This is what would be a research.

DDOS is vast area of research. you should narrow down your area. you can go with smurf attack, data flooding attack pattern.

Thanks Mr. Vikram and Mr Dheeraj for your valuable contributions. How about narrowing down the research on Smurf attack pattern recognition as a part of proactive attack detection?

Thanks

Actually, most of the researchers are now looking forward for the detection and prevention of DoS/DDoS attacks in IPv6 also. So I think its better if you keep in mind both of the IP versions before proposing any detection or prevention solution.