Software bought revolutionary change making entrepreneurs fortunate enough to make money in less time with least effort and correct output. SDLC (Software development life cycle) is responsible for software's reliability, performance, scalability, functionality and maintainability. Although all phases of SDLC have their own importance but Software architecture serves as the foundation for other phases of SDLC. Just like sketch of a building helps constructor to correctly construct the building, software architecture helps software developer to develop the software properly. There are various styles available for software architecture. In this paper, clear picture of all important software architecture styles are presented along with recent advancement in software architecture and design phases. It could be helpful for a software developer to select an appropriate style according to his/her project's requirement. An architectural style must be chosen correctly to get its all benefits in the system. All the architectural styles are compared on the basis of various quality attributes. This paper also specifies the application area, advantages and disadvantages of each architectural style.

Information Technology is playing a game changing role in life of human being. Healthcare is one of the prime concerns of every human being. This research work is based on diabetes, a chronic disease which is very common in all over the world. A decision support system may help doctors for decision-making and it may also support to an individual to take decision after filling the details of his or her diagnosis report. In this research work, development of a decision support system based on ant colony optimized neural network has been done which is hybrid of feature selection with ant colony neural network. A comparative analysis of ant colony optimized neural network and hybrid ant colony optimized neural network on the basis of sum of squared error is also performed in this research work.