Network Programming Interview Preparation Guide

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SSL stands for Secure Sockets Layer, a protocol developed by Netscape for transmitting private documents via internet. It works by encrypting data sent over SSL connection.
URLs that require a SSL connection starts as https. Browsers like Netscape navigator and Internet Explorer support SSL.

Java Object Serialization and HTTP. The Object Serialization protocol is used to marshal call and return data. The HTTP protocol is used to "POST" a remote method invocation and obtain return data when circumstances warrant.

The key difference is that JSF runs on the server in a standard Java servlet container like Tomcat or WebLogic and display HTML or some other markup to the client.

JSF stands for JavaServer Faces, or simply Faces. It is a framework for building Web-based user interfaces in Java. Like Swing, it provides a set of standard widgets such as buttons, hyperlinks, checkboxes, ans so on.

A URL instance represents the location of a resource, and a URLConnection instance represents a link for accessing or communicating with the resource at the location.

You obtain a URL instance and then invoke openConnection on it. URLConnection is an abstract class, which means you can't directly create instances of it using a constructor. We have to invoke openConnection method on a URL instance, to get the right kind of connection for your URL. Eg. URL url;
URLConnection connection; try{ url = new URL("..."); connection = url.openConnection(); }catch (MalFormedURLException e) { }

A socket is one end-point of a two-way communication link between two programs running on the network. A socket is bound to a port number so that the TCP layer can identify the application that data is destined to be sent. Socket classes are used to represent the connection between a client program and a server program. The java.net package provides two classes--Socket and ServerSocket--which implement the client side of the connection and the server side of the connection, respectively.

The Local System's IP Address and Port Number. And the Remote System's IPAddress and Port Number.

When the specified URL is not connected then the URL throw MalformedURLException and If InetAddress? methods getByName and getLocalHost are unable to resolve the host name they throw an UnknownHostException.

Socket and ServerSocket. ServerSocket is used for normal two-way socket communication. Socket class allows us to read and write through the sockets. getInputStream() and getOutputStream() are the two methods available in Socket class.