Abstract
One of the major activities in software design is defining software architecture. Before designing software structure and software behavior we have to define its architecture. In this paper we have proposed three-tiered software architecture. This software architecture extends application logic tier with security. We have implemented two important security issues: authentication and authorization processes. These processes are implemented through software patterns. The software patterns have the particular place in the Proposed Software Architecture (PSA). In this paper, we have presented these software patterns and explained why they are important in PSA.