Table of contents Introduction Client & server 2tier architecture 3tier architecture Applications of 2 & 3 tier architecture Conclusion
Introduction What is client?? What is server??
What is client?? Client (computing), software that accesses a remote service on another computer known as a server, by way of a network
What is server?? A server is a computer, or series of computers, that link other computers or electronic devices together For example, when you enter a query in a search engine, the query is sent from your computer over the internet to the servers that store all the relevant web pages. The results are sent back by the server to your computer.
Peer to peer architecture Peer-to-peer (P2P) computing or networking is a distributed application architecture that partitions tasks or work loads between peers. Peers are equally privileged, equipotent participants in the application.
Coming back to client – server architecture • A client makes a request to connect to a server for providing some service. • The services running on the server run on known ports and the client needs to know the address of the server machine and this port in order to connect to the server. • The first packet which the client sends as a request to the server contains this information and this is then further used by the server to send any information.
What is a Two-Tier Architecture? A two-tier architecture is where a client communicate directly to a server. It is typically used in small environments.
In two-tier architecture, the server holds both the application tier (Business Logic) and the data tier (data).
Advantage & DisadvantageAdvantages Disadvantages Simple structure Poor performance Dependability Easy to setup and maintain Non-Scalable Not portable to other Good for small user groups database server.
What is a 3-Tier Architecture In 3-tier architecture, there is an intermediary level, meaning the architecture is generally split up between: A client, i.e. the computer which requests the resources, equipped with a user interface (usually a web browser for presentation purposes The Application server (also called middleware), whose task is to provide the requested resources, but by calling on another server The data server, which provides the application server with the data it requires
Various Web Servers Apache - Web site hosted 378,267,399 (64.91%) IIS (MS) - 84,288,985 (14.46%) Nginx GWS Oracle (Sun) SSI, CGI, SCGI, FastCGI, PHP, Java Servlet, JavaServer Pages, ASP, ASP .NET, Server API , JS, AJAX
Various Application Servers IBM Webshpere Jboss Oracle App. Server Tomcat WEbLogic Silver Stream
Various Database Servers Oracle DB2 SQL Server Informix Ingress