I hereby declare that this thesis contains literature survey and original research work by the undersigned, as part of requirements of the Degree of M.Tech. (IT) in Software Engineering. All information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all materials and results that are not original to this work.-I hereby declare that this thesis contains literature survey and original research work by the　undersigned, as part of requirements of the Degree of M.Tech. (IT) in Software Engineering. All information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all materials and results that are not original to this work.