We get following advantages by using JSP in web architecture...

1 - Performance : JSP provides very good performance due to their design of using same code to service multiple requests.

2 - Fast : Since JSP is pre-compiled, server can serve the pages very fast.

3 - Extendable : JSP is based on Java Servlets. This helps in extending JSP architecture with other Java technologies like JDBC, JMS, JNDI etc.

4 - Design : It is easier to design user interface with JSP, since it is very close to HTML. UI designers can create a JSP with mock data and developers can later provide implementation of dynamic data.