I am having a confusion between 4 topics to choose from for my final year cs project which are as follows:- 1) Secure intrusions system against DDOS attacks in wireless networks
2) Embedded Extended Visual Cryptography Schemes:- In this system we can encode the image and share it instead of using high level cryptography methods that too without losing visual image quality and image pixel size
3) Increasing DNS security by using cryptographic techniques:- combining the concept of both the Digital Signature and Asymmetric key (Public key) Cryptography.

4) Fuzzy key search over encrypted data in cloud computing.

Kindly help me in deciding the project for my final year that i can successfully complete in one semester approx. I know java and in networking i have read ferozan.