Answer:- Caching server provides functionality like • Reverse proxy and content based routing • Integration with servlet caching and dynamic content caching

Answer:- Websphere MQ programming APIs include AMI (Application Messaging Interface) JMS (Java Message Service) MQI (Message Queue Interface)

Answer:- Class loader policy, JAAS authentication aliases and virtual host information can enhance EARs support apart from EARs support and shared libraries.

Answer:- In Websphere application can be deployed in three ways Copy files directly to deploy application folder in websphere Use websphere specific ant tasks create automated scripts for deploying application Via administration console

Answer:- WAS (WebServer Application Server) stores all the configuration in one central location referred as “Master Repository”. The sync ensures the configuration in both local and master repositories are same and in sync.

Answer:- Connecting pool is a cache of database connections maintained so that connection can be re-used when future requests to the database are required. If all the connections are occupied, a new connection is created and is added to the pool.

Answer:- Websphere is focused more on connectivity, integration, and web services. It has better performance, rich implementation of J2EE, more extensive integration and transaction management compare to Weblogic. Weblogic has default transaction attributes as supports, while websphere does not have such type of the default transaction attribute.

Answer:- Nginx is a web server and a reverse proxy server for HTTP, HTTPS, SMTP, POP3 and IMAP protocols.

Answer:- Special features of the Nginx server includes • Reverse proxy/ L7 Load Balancer • Embedded Perl interpreter • On the fly binary upgrade • Useful for re-writing URLs and awesome PCRE support

Answer:- Nginx uses the reactor pattern. The main event loop waits for the OS to signal a readiness event- such that the data is accessible to read from a socket, at which instance it is read into the buffer and processed. A Single thread can serve tens of thousands of simultaneous connections.

Answer:- A server that just drops the requests can be defined as Server { listen 80; server_name " " ; return 444; } Here the server name is kept as an empty string which will match request without the “Host” header field, and a special Nginx’s non-standard code 444 is returned that terminates the connection.

Answer:- The reverse proxy server can hide the presence and characteristics of the origin server. It acts as an intermediate between internet cloud and web server. It is good for security reason especially when you are using web hosting services.

Answer:- The best usage of Nginx server is to deploy dynamic HTTP content on a network with using SCGI, WSGI application servers, FastCGI handlers for scripts. It can also serve as a load balancer.

Answer:- • Master processes: It reads as well as evaluates configuration and maintains worker processes. • Worker processes: It actually does the processing of the requests.