5h55 5 5
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By Nitika Sharma
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CHAPTER
NO.
TITLE
PAGE NO.
TITLE PAGE
……….i
ABSTRACT
………..ii
ACKNOWLEDGEMENT
……….iii
LIST OF TABLES & FIGURES
………iv
1. INTRODUCTION
1.1 Types of Peer to Peer
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2
1.1.1 Unstructured P2P
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2
1.1.2 Centralized P2P
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3
1.2 Applications
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3
1.3 Advantages
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3
1.4 Objective
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4
1.5 Scope
……….……….………….
4
2. FEATURES OF PROJECT
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5
3.
HARDWARE & SOFTWARE REQUIREMENTS
3.1 Input Requirements
……….………..
8
4
3.3 Software Requirements
……….………..
8
3.4 Hardware Requirements
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8
4. TOOL USED FOR DEVELOPMENT
4.1 NetBeans
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10
4.1.1 Features and Tools
………..………..………..…….
10
4.1.2 Source Code Editor
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10
4.1.3 GUI Builder
………..11
5. TECHNOLOGY TO BE USED
5.1 Introduction to Java
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13
5.1.1 Java Virtual Machine
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13
5.1.2 Principles
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13
5.1.3 Versions
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14
5.1.4 Features of Java Language
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14
5.2 Multi Threading
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16
5.2.1 Benefits of using threads
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17
5.2.2 Life Cycle of a Thread
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17
5.2.3 Thread Priority in Java
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18
5.3 Socket Programming in Java
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19
5.3.1 Ports and Sockets
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20
5.4 Networking In Java
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22
5
6.1 Sotware Development Life Cycle
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24
6.2
Different Phases………..
25
7. PROJECT PLANNING
7.1 Project Planning & Scheduling
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26
7.2 Sotware Configuration Management
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28
7.3 Problem Analysis
……….…………
29
8. REQUIREMENT ANALYSIS
8.1 Requirement Analysis
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30
8.2 Types of Requirements
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32
9. OVERALL NETWORK ARCHITECTURE
9.1 Client/ Server Model
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33
9.1.1 Client/Server Limitation
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35
9.2 P2P Architecture
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36
10. MODULES
10.1
Create Main P2P Server
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38
10.2
Create Main P2P Client
……… ………...
39
10.3
Create Miniserver & Miniclient
………
40
10.4
Manage Online or Offline User List
………...
41
10.5
Sharing Files On P2P Network
………
42
6
10.7
Sharing Files On Peers & Sending Results Back
…………..
44
10.8
Downloading File From Other Peer .
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45
10.9
Peers Can Chat & Ask Other Peers To Share Files
……..
46
11. DESIGN
11.1
Design Phase
………..
48
12. DATA FLOW DIAGRAMS
12.1 Introduction
………
50
12.2 Level - 0 Basic Working
………..………..
51
12.3 Level – 1 Get List Of Online Clients
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52
12.4
Sharing Files By Clients
………....
52
12.5
Downloading Files By Clients From Other Peers
………
53
13. CLASS DIAGRAMS
13.1
Class Diagram Of Main Server
………
54
13.2
Class Diagram Of Client
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55
14. GANTT CHART
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56
15. SNAPSHOTS & CODING
15.1 Welcome Screen
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58
15.2 P2P Main Server
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59
15.3 Constraints
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60
15.4 Client GUI
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62
15.5 Searching of a file
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64
15.6 Downloading File
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66
7
15.6.2 Shared Folder
……..………..
68
15.6.3 To Download existing file
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68
15.6.4 To Rename the file
………...
69
15.7
Changing the Shared Path
………..………...
71
15.8
To Test the Speed
……….……..
74
15.9 To View Attached Peers
……….……...
77
15.10
To view Download History
……….…...
79
15.11
To cancel Download
………
80
15.12
Message Sending
……….….
83
15.13
Changing Themes
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86
15.14
Coding of client & inner classes
………...
88
12.
FUTURE & FURTHER ENHANCEMENT OF PROJECT
…………...144
13.
APPENDIX
……….…….145
8
LIST OF TABLES & FIGURES
Tables Page No.
5.1
Thread Priority
………...
18
Figures
5.1 Life Cycle Of Thread
………..….
17
5.3 Socket Programming
………...
19
5.3.1 Connection request from Client
………..………..
20
5.3.2 Connection Build From Server
………...
21
5.4 Ports help Computer to Identify service
………...
22
6.1 SDLC Waterfall Model
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24
9.1 Client Server Interaction
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34
9.2.1 P2P Architecture
………...
36
11.1 Design Phase
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48
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CHAPTER 1
PEER 2 PEER FILE SHARING SYSTEM
WITH CHAT
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INTRODUCTION TO THE PROJECT
The project is Java Based Peer to Peer( P2P) File Sharing System with chat.Point-to-Point (P2P) technology enables the sharing of computer resources such as files by a direct exchange between end-users computers. P2P networking means files are not stored on a central server. Instead, client software (such as the popular Kazaa, Limewire) works as a server for shared files on an individual's computer. This allows each computer with the software to act as a mini-server from which other P2P users can download files. P2P's popularity stems from its easy-to-use, convenient setup that has empowered informal networks of file sharers to make files available to each other around the globe.P2P communication has the following characteristics:
Direct connections between network clients
Each client (node) is considered as an equal to all others Clients share processing, applications and content There is no central point of control within the network.
Peer-to-peer computing is the sharing of computer resources and services by direct exchange between systems. In a peer-to-peer architecture, computers that have traditionally been used solely as clients communicate directly among themselves and can act as both clients and a server, assuming whatever role is most efficient for the network.
Another big attraction of file-sharing is cost : Users can download as many songs as they like
from each other, for free. With the price of CDs often well over $20, many music-lovers have engaged in file-sharing despite the legal risks involved.
Moreover, many consumers are loath to spend $20 for a compilation of songs when they are really only interested in one of the tracks on the CD. They may turn to file-sharing in order to download the one song that they want, without having to purchase the full CD.
1.1 Types of Peer To Peer Network
1.1.1
Unstructured peer-to-peer network:
It do not impose any structure on the overlay networks. Peers in these networks connect in an ad-hoc fashion. Ideally, unstructured P2P systems would have absolutely no centralized system, but in practice there are several types of unstructured systems with various degrees of centralization.There are two main types of unstructured P2P networks:
Pure peer-to-peer systems :
The entire network consists solely of equipotentpeers. There is only one routing layer, as there are no preferred nodes with any special infrastructure function.
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Hybrid peer-to-peer systems:
These systems allow such infrastructure nodes toexist, often called supernodes.A pure P2P network does not have the notion of clients or servers but only equal peer nodes that simultaneously function as both "clients" and "servers" to the other nodes on the network.
1.1.2 Centralized peer-to-peer network:
In this, central server is used for indexingfunctions and to bootstrap the entire system. Although this has similarities with a structured architecture, the connections between peers are not determined by any algorithm.
1.2 Applications
Many file sharing networks, such as gnutella, G2 and the eDonkey network popularized peer to peer technologies. From 2004 on, such networks form the largest contributor of network traffic on the Internet.
Peer-to-peer content delivery networks (P2P-CDN). Peer-to-peer content services, e.g. caches for improved performance such as Correli Caches.
Software publication and distribution (Linux, several games) via file sharing networks.
1.3 Advantages
In P2P networks clients provide resources, which may include bandwidth, storage space and computing power. This property is one of the major advantages of using P2P networks because it makes the setup and running costs very small for the original content distributor. As nodes arrive and demand on the system increases, the total capacity of the system also increases, and the likelihood of failure decreases. If one peer on the network fails to function properly, the whole network is not compromised or damaged. In contrast, in a typical client– server architecture, clients share only their demands with the system, but not their resources. In this case, as more clients join the system, fewer resources are available to serve each client, and if the central server fails, the entire network is taken down.
The decentralized nature of P2P networks increases robustness because it removes the single point of failure that can be inherent in a client-server based system.
Another important property of peer-to-peer systems is the lack of a system administrator. This leads to a network that is easier and faster to setup and keep running because a full staff is not required to ensure efficiency and stability. Decentralized networks introduce new security issues because they are designed so that each user is responsible for controlling their data and resources.A user may encounter harmful data by downloading a file that was originally uploaded as a virus disguised in an .exe, .mp3, .avi, or any other filetype.
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1.4 Objective
The objective of the Project is to allow users to download media files such as music, movies, and games using a P2P software client that searches for other connected computers. The "peers" are computer systems connected to each other through the Internet. Thus, the only requirements for a computer to join peer-to-peer networks are an Internet connection and P2P software. The first generation of P2P software is Napster, a central server-based model that was eventually shut down. The second generation of P2P software is Gnutella and Kazaa ,which are user-based models. BitTorrent became the third generation of P2P networks.
File transfers involve two computers, often designated as a client and a server and most operations are for the copying files from one machine to another.Most WEB and FTP servers are punished for being popular. Since all uploading is done from one central place, a popular site needs more resources (CPU and bandwidth) to be able to cope. With the use of P2P, the clients automatically mirror the files they download, easing the publisher's burden.
Peer to Peer File Sharing System allows peers to search , download and upload files to other peers by just having the list of online clients from server. Peers manage on their own for downloading files.A chat feature is also added so that they can chat with their friends.
1.5 Scope
You can configure computers in peer to peer workgroups to allow sharing of files, printers and other resources across all of the devices. Peer networks allow data to be shared easily in both directions, whether for downloads to your computer or uploads from your computer.
On the Internet, peer to peer networks handle a very high volume of file sharing traffic by distributing the load across many computers. Because they do not rely exclusively on central servers, P2P networks both scale better and are more resilient than client-server networks in case of failures or traffic bottlenecks.
Peer to peer networking is common on small local area networks (LANs), particularly home networks. Both wired and wireless home networks can be configured as peer to peer environments.
Computers in a peer to peer network run the same networking protocols and software. Peer networks are also often situated physically near to each other, typically in homes, small businesses or schools. Some peer networks, however, utilize the Internet and are geographically dispersed worldwide.
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CHAPTER 2
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FEATURES OF PROJECT
There are several features of P2P file sharing system:
1. Creating Main P2P Server.
2. Creating Main P2P Client.
3. Creating Miniserver on P2P Client.
4. Creating Miniclient on P2P Client.
5. Manage online or offline user Lists in real time.
6. Sharing files on P2P Network.
7. Receive search request.
8. Search file on peers and sending results to other peer, who made search request.
9. Downloading File from other peer.
10. Uploading file to other.
11.Peers can change their Shared Path
12. Peers can chat and ask other peer to share files.
13. View Attached Peers.
14. To View the download history.
15. To check the link speed of uploading clients.
16.Peer can cancel downloading of the file.
Last but not the least feature is : Peers can change the themes of client GUI according to their choice.
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CHAPTER 3
HARDWARE & SOFTWARE
REQUIREMENTS
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3.1 INPUT REQUIREMENTS
The Point-to-Point sharing System will have a minimum set of following requirements:
Login: Whenever user tries to connect to the server it must provide a valid I.P address to access the server. On the basis of server address either the user i.e. client system is connected to the server or denied the access.
Online-clients: Once the client and server gets successfully connected the next thing that is mandatory for the system is that server must show the list of the clients that are active that time. It is important because some of the clients may be down so the user must not keep accessing the offline clients.
Search: Once the online clients are displayed the interface must provide the facility to search the file. Search file should have the functionality that it must indicate the paths of all the system that have that file as specified by the user.
Selection: After listing the user should select one client that he/she finds the best and enables downloading.
Downloading: While the downloading starts, progress bar keeps on indicating that the file has been downloaded successfully or not.
3.2 OUTPUT REQUIREMENTS
The Point-to-Point sharing System has a minimum set of following output requirements: Space: Downloading client must have surplus space at his\her HDD(C:\shared folder)
Message: Successful downloading of a particular file is indicated by a message at the monitor screen of the downloading client.
3.3 SOFTWARE REQUIREMENTS
Windows , LINUX , Macintosh Java Virtual Machine
3.4 HARDWARE REQUIRMENTS
Pentium 4 Computer 256 MB RAM
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CHAPTER
4
TOOL USED FOR DEVELOPMENT
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4.1 NETBEANS
NetBeans is an IDE (Interactive Development Environment) Software which has been used in this project to make the software. The NetBeans IDE is an open-source integrated development environment written entirely in Java using the NetBeans Platform. NetBeans IDE supports development of all Java application types out of the box. NetBeans is a user-friendly interactive software for Java based applications. This can be downloaded from the company’s website for free. The advantage of using NetBeans is that we can build and run the project in same interface window. The NetBeans Platform allows applications to be developed from a set of modular software components called modules. A module is a Java archive file that contains Java classes written to interact with the NetBeans Open APIs and a manifest file that identifies it as a module. Applications built on modules can be extended by adding new modules. Since modules can be developed independently, applications based on the NetBeans platform can be extended by third party developers..
Using an Integrated Development Environment (IDE) for developing applications saves you time by managing windows, settings, and data. In addition, an IDE can store repetitive tasks through macros and abbreviations. Drag-and-drop features make creating graphical user interface (GUI) components or accessing databases easy, and highlighted code and debugging features alert you to errors in code.
NetBeans provides the services common to creating desktop applications -- such as window and menu management, settings storage -- and is also the first IDE to fully support JDK 6.0 features. The NetBeans platform and IDE are free for commercial and noncommercial use, and they are supported by Sun Microsystems.
4.1.1 Features and Tools
The NetBeans IDE has many features and tools for each of the Java platforms. Those in the following list are not limited to the Java SE platform but are useful for building, debugging, and deploying applications and applets :
4.1.2 Source Code Editor
Syntax highlighting for Java, JavaScript, XML, HTML, CSS, JSP, IDL Customizable fonts, colors, and keyboard shortcuts
Live parsing and error marking
Pop-up Javadoc for quick access to documentation Advanced code completion
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Automatic indentation, which is customizable Word matching with the same initial prefixes
Navigation of current class and commonly used features Macros and abbreviations
Goto declaration and Goto class Matching brace highlighting
JumpList allows you to return the cursor to previous modification
4.1.3 GUI Builder
Fully WYSIWYG designer with Test Form feature Support for visual and nonvisual forms
Extensible Component Palette with preinstalled Swing and AWT components Component Inspector showing a component's tree and properties
Automatic one-way code generation, fully customizable
Support for AWT/Swing layout managers, drag-and-drop layout customization Powerful visual editor
Support for null layout
In-place editing of text labels of components, such as labels, buttons, and text fields
JavaBeans support, including installing, using, and customizing properties, events, and customizers
Visual JavaBean customization -- ability to create forms from any JavaBean classes Connecting beans using Connection wizard
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CHAPTER 5
TECHNOLOGY TO BE USED
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5.1 INTRODUCTION TO JAVA
Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities. Java applications are typically compiled to byte code (class file) that can run on any Java Virtual Machine (JVM) regardless of computer architecture. Java is a general-purpose, concurrent, class-based, object-oriented language that is specifically designed to have as few implementation dependencies as possible. It is intended to let application developers "write once, run anywhere" (WORA), meaning that code that runs on one platform does not need to be recompiled to run on another. Java is currently one of the most popular programming languages in use, particularly for client-server web applications, with a reported 10 million users.The original and reference implementation Java compilers, virtual machines, and class libraries were developed by Sun from 1995. Main advantage of java programming language is platform independence, which means any application written in java can be operated on any of the platform, instead of having to produce separate versions of the application for each computer and operating system.
5.1.1 Java virtual machine
A Java virtual machine (JVM) is a virtual machine capable of executing Java bytecode.A Java virtual machine is software that is implemented on virtual and non-virtual hardware and on standard operating systems. A JVM provides an environment in which Java bytecode can be executed, enabling such features as automated exception handling, which provides "root-cause" debugging information for every software error (exception), independent of the source code. A JVM is distributed along with a set of standard class libraries that implement the Java application programming interface (API). Appropriate APIs bundled together with JVM form the Java Runtime Environment (JRE).The use of the same bytecode for all JVMs on all platforms allows Java to be described as a "write once, run anywhere" programming language, as opposed to "write once, compile anywhere", which describes cross-platform compiled languages. Thus, the JVM is a crucial component of the Java platform.
5.1.2 Principles
There were five primary goals in the creation of the Java language : It should be "simple, object-oriented and familiar"
It should be "robust and secure"
It should be "architecture-neutral and portable" It should execute with "high performance" It should be "interpreted, threaded, and dynamic"
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5.1.3 Versions
Major release versions of Java, along with their release dates : JDK 1.0 (January 23, 1996) JDK 1.1 (February 19, 1997) J2SE 1.2 (December 8, 1998) J2SE 1.3 (May 8, 2000) J2SE 1.4 (February 6, 2002) J2SE 5.0 (September 30, 2004) Java SE 6 (December 11, 2006) Java SE 7 (July 28, 2011)
5.1.4 Features of Java Language
The basic features that make Java a powerful and popular programming language:
Platform Independence: The Write-Once-Run-Anywhere ideal has not been achieved, but closer than with other languages.
Object Oriented: Object oriented throughout - no coding outside of class definitions, including main(). An extensive class library available in the core language packages.
Compiler/Interpreter Combo: Code is compiled to bytecodes that are interpreted by a Java virtual machines (JVM) .This provides portability to any machine for which a virtual machine has been written.The two steps of compilation and interpretation allow for extensive code checking and improved security.
Automatic Memory Management : Automatic garbage collection - memory management handled by JVM.
Security
No memory pointers
Programs run inside the virtual machine sandbox.
Dynamic Binding : The linking of data and methods to where they are located, is done at run-time.New classes can be loaded while a program is running. Linking is done on the fly.
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Good Performance : Interpretation of byte codes slowed performance in early versions, but advanced virtual machines with adaptive and just-in-time compilation and other techniques now typically provide performance up to 50% to 100% the speed of C++ programs.
Threading : Lightweight processes, called threads, can easily be spun off to perform multiprocessing.Can take advantage of multiprocessors where available.Great for multimedia displays.
Built-in Networking : Java was designed with networking in mind and comes with many classes to develop sophisticated Internet communications.
Several features of C & C++ eliminated: No memory pointers
No preprocessor
Array index limit checking
Features such as eliminating memory pointers and by checking array limits greatly help to remove program bugs. The garbage collector relieves programmers of the big job of memory management. These and the other features can lead to a big speedup in program development compared to C/C++ programming.
Java I/O Routines : Java provides several tools for the input and output of data, ranging from the Abstract Window Toolkit (AWT) or the Swing Components to the core System functions of Java classes. The AWT is exactly what it says it is: a set of components for designing windows and graphical user interfaces that uses the peer components of the underlying operating system for their implementation.
Streams : Java provides several different kinds of streams, each designed to handle a different kind of data. The standard input and output streams form the basis for all the others.InputStream and OutputStream are both available for you to use as is, or you can derive more complicated stream schemes from them. In order to create the other kinds of Java streams, first you must create and define the basic streams.
Perhaps the most-used stream formats are the DataInputStream and the DataOutputStream. Both of these streams enable you to read or write primitive data types, giving you the flexibility within your application to control the results of your application's execution. Without this kind of functionality, you would have to write specific bytes rather than reading specific data.
Input and Output Using System Class: One of the classes Java includes in every applet or application, whether you specify that it do so or not, is the System class. The System class
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provides support for input/output (I/O) using the Java console; you are to provide the ability to write to the console, read from the console, and write errors to the user. The Java console is provided in two ways, one for browsers and one for applications. In the browser environment the console is a separate browser window that has controls for scrolling and clearing. For applications run from the operating system (OS) command line, the console is the text interface you see and suffers the same problems as the text base OS environment (lack of scrolling backwards
Input Using the System Class
Input in the System class is actually handled by the InputStream class contained in the Java I/O routines. System.in is an object of type InputStream that is created, maintained, and initialized by the System class. In other words, it's yours for the taking; you don't have to do a thing to use it.
Output Using the System Class
As with input, output is handled through streams. How can output be a stream if a stream is a sequence of characters from a source? Well, the source is your application, and the stream is routed to a device known as the standard output. The standard output is usually your monitor, but it could be other things as well. Most notably, the standard output is set to be the Java console when an applet runs within Netscape Navigator.
5.2 Multi-threading in Java
Nearly every operating system supports the concept of processes -- independently running programs that are isolated from each other to some degree. Threading is a facility to allow multiple activities to coexist within a single process. Most modern operating systems support threads, and the concept of threads has been around in various forms for many years. Java is the first mainstream programming language to explicitly include threading within the language itself, rather than treating threading as a facility of the underlying operating system.
Threads are sometimes referred to as lightweight processes. Like processes, threads are independent, concurrent paths of execution through a program, and each thread has its own stack, its own program counter, and its own local variables. However, threads within a process are less insulated from each other than separate processes are. They share memory, file handles, and other per-process state.A process can support multiple threads, which appear to execute simultaneously and asynchronously to each other. Multiple threads within a process share the same memory address space, which means they have access to the same variables and objects, and they allocate objects from the same heap. The Java thread facility and API is deceptively simple. However, writing complex programs that use threading effectively is not quite as simple. Because multiple threads coexist in the same memory space and share the same variables, you must take care to ensure that your threads don't interfere with each other.Multithreading enables
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you to write very efficient programs that make maximum use of the CPU, because idle time can be kept to a minimum.
5.2.1 Benefits of using threads:
The Java language includes a powerful threading facilitybuilt into the language. The threading facility can be used to: Increase the responsiveness of GUI applications
Take advantage of multiprocessor systems
Simplify program logic when there are multiple independent entities Perform blocking I/O without blocking the entire program
When multiple threads execute byte-code instruction sequences in the same program, that action is known as multithreading.
5.2.2 Life Cycle of a Thread :
A thread goes through various stages in its life cycle. Forexample, a thread is born, started, runs, and then dies. Following diagram shows complete life cycle of a thread.
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5.2.3 Thread Priority In Java
In Java, thread scheduler can use the thread priorities in the form of integer value to each of its thread to determine the execution schedule of threads . Thread gets the ready-to-run state according to their priorities. The thread scheduler provides the CPU time to thread of highest priority during ready-to-run state. Priorities are integer values from 1 (lowest priority given by the constant Thread.MIN_PRIORITY) to 10 (highest priority given by the constant Thread.MAX_PRIORITY). The default priority is 5 (Thread.NORM_PRIORITY).
Table 5.1 : Thread Priority
METHODS DESCRIPTION
setPriority( ) This is method is used to set the priority of thread. getPriority( ) This is method is used to get the priority of thread.
Multithreading benefits a program in various ways:
Multithreaded GUI (graphical user interface)-based programs remain responsive to users while performing other tasks, such as repaginating or printing a document.
Threaded programs typically finish faster than their non-threaded counterparts. This is especially true of threads running on a multiprocessor machine, where each thread has its own processor.Java accomplishes multithreading through its java.lang.Threadclass. Each Thread object describes a single thread of execution. That execution occurs in Thread's run() method. Because the default run() method does nothing, you must subclass Thread and override run() to accomplish useful work.
Multithreading has several advantages over Multiprocessing such as:
Threads are lightweight compared to processes
Threads share the same address space and therefore can share both data and code Context switching between threads is usually less expensive than between processes
Cost of thread intercommunication is relatively low that that of process intercommunication
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5.3 Socket Programming
URLs and URLConnections provide a relatively high-level mechanism for accessing resources on the Internet. Sometimes your programs require lower-level network communication, for example, when you want to write a client-server application.In client-server applications, the server provides some service, such as processing database queries or sending out current stock prices. The client uses the service provided by the server, either displaying database query results to the user or making stock purchase recommendations to an investor. The communication that occurs between the client and the server must be reliable. That is, no data can be dropped and it must arrive on the client side in the same order in which the server sent it.
TCP provides a reliable, point-to-point communication channel those client-server applications on the Internet use to communicate with each other. To communicate over TCP, a client program and a server program establish a connection to one another. Each program binds a socket to its end of the connection. To communicate, the client and the server each reads from and writes to the socket bound to the connection.
Figure 5.3 : Socket Programming
Syntax
// for tcp client side
Socket s= new Socket (InetAddress adr, int port);
//for server side
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5.3.1 Ports and Sockets
These entities lie at the heart of network communications. For anybody not already familiar with the use of these terms in a network programming context, the two words very probably conjure up images of hardware components.
Port: A port is a logical connection to a computer (as opposed to a physical connection) and is
identified by a number in the range 1-65535. This number has no correspondence with the number of physical connections to the computer, of which there may be only one (even though the number of ports used on that machine may be much greater than this).
Ports are implemented upon all computers attached to a network. Each port may be dedicated to a particular server/service (though the number of available ports will normally greatly exceed the number that is actually used). Port numbers in the range 1-1023 are normally set aside for the use of specified standard services. For example, port 80 is normally used by Web servers for HTTP.
In most applications, of course, there are likely to be multiple clients wanting the same service at the same time. A common example of this requirement is that of multiple browsers (quite possibly thousands of them) wanting Web pages from the same server. The server, of course, needs some way of distinguishing between clients and keeping their dialogues separate from each other. This is achieved via the use of sockets.
Socket: Normally, a server runs on a specific computer and has a socket that is bound to a
specific port number. The server just waits, listening to the socket for a client to make a connection request. A socket is one end-point of a two-way communication link between two programs running on the network. 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--that implement the client side of the connection and the server side of the connection, respectively.
On the client-side: The client knows the hostname of the machine on which the server is
running and the port number on which the server is listening. To make a connection request, the client tries to rendezvous with the server on the server's machine and port. The client also needs to identify itself to the server so it binds to a local port number that it will use during this connection. This is usually assigned by the system.
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If everything goes well, the server accepts the connection. Upon acceptance, the server gets a new socket bound to the same local port and also has its remote endpoint set to the address and port of the client. It needs a new socket so that it can continue to listen to the original socket for connection requests while tending to the needs of the connected client.
Figure 5.3.1 : Server side
On the client side, if the connection is accepted, a socket is successfully created and the client can use the socket to communicate with the server. The client and server can now communicate by writing to or reading from their sockets.
The following steps occur when establishing a TCP connection between two computers using sockets:
The server instantiates a ServerSocket object, denoting which port number communication is to occur on.
The server invokes the accept() method of the ServerSocket class. This method waits until a client connects to the server on the given port.
After the server is waiting, a client instantiates a Socket object, specifying the server name and port number to connect to.
The constructor of the Socket class attempts to connect the client to the specified server and port number. If communication is established, the client now has a Socket object capable of communicating with the server.
On the server side, the accept() method returns a reference to a new socket on the server that is connected to the client's socket.
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5.4 NETWORKING IN JAVA
The Internet is composed of millions of computers, located all across the globe; each of these computers will have a unique IP address.IP addresses are 32-bit numbers, containing four octets (8 bit numbers) separated by a full stop. Each computer with a direct internet connection will have a unique IP address, (e.g. 207.68.156.61). Some computers have temporary addresses, such as when you connect to your ISP through a modem. Others have permanent addresses, and some even have their own unique domain names (e.g. www.microsoft.com).For example, most web servers use port 80. Of course, you can use any port you like – there’s no rule that says you must use 80.
Figure 5.4: Ports help computers to identify which service data is for
Advantages of Networking
Networking has a lot of advantages over traditional advertising and marketing. These are the most important advantages:
More business : As you develop networking skills and contacts, you’ll find that the amount of work you get from referrals accounts for the largest part of your new business. And the most profitable.
Better business : The business you get from referrals will usually be from happy customers. This will mean that your best customers, those who pay on time and without headaches, will be the ones who send you the additional business.
Cost savings : As you get more business through referrals, you’ll find less and less need to advertise and market your business. This means less of the associated costs. And since you’ll be getting better quality business, it means less bad debts.
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CHAPTER 6
SOFTWARE DEVELOPMENT
LIFE CYCLE
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6.1 Software Development Life Cycle (SDLC)
The Systems Development Life Cycle (SDLC) is a conceptual model used in project management that describes the stages involved in an information system development project from an initial feasibility study through maintenance of the completed application. Some methods work better for specific types of projects, but in the final analysis, the most important factor for the success of a project may be how closely particular plan was followed.
The image below is the classic Waterfall model methodology, which is the first SDLC method and it describes the various phases involved in development.
Figure 6.1 : The SDLC Waterfall Model
The relationship of each stage to the others can be roughly described as a waterfall, where the outputs from a specific stage serve as the initial inputs for the following stage. During each stage, additional information is gathered or developed, combined with the inputs, and used to produce the stage deliverables.
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6.2 Different Phases
System planning
The system planning is used to determine if the project should get the go-ahead. If the project is to proceed, the system plan will produce a project plan and budget estimates for the future stages of development.
Requirement Analysis and Design
Analysis gathers the requirements for the system. Design focuses on high level design like, what programs are needed and how are they going to interact. During these phases, the software's overall structure is defined. Analysis and Design are very crucial in the whole development cycle. The logical system of the product is developed in this phase.
Development and Coding
In this phase the designs are translated into code. Computer programs are written using a conventional programming language. Various Programming tools are used to generate the code. Different high level programming languages like PHP, Java are used for coding.
Integration and Testing
In this phase the system is tested. Normally programs are written as a series of individual modules, this subject to separate and detailed test. The system is then tested as a whole. The separate modules are brought together and tested as a complete system. The system is tested to ensure that interfaces between modules work together.
Maintenance
Inevitably the system will need maintenance. Software will definitely undergo change once it is delivered to the customer. Change could happen because of some unexpected input values into the system. In addition, the changes in the system could directly affect the software operations. The software should be developed to accommodate changes that could happen during the post implementation period.
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CHAPTER 7
PROJECT PLANNING & PROBLEM
ANALYSIS
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7.1 PROJECT PLANNING & SCHEDULING
The planning stage establishes a bird’s eye view of the intended software product, and uses this to establish the basic project structure, evaluate feasibility and risks associated with the project, and describe appropriate management and technical approaches”
Project planning is part of Project Management. It is a well-established approach to managing and controlling the introduction of new initiatives or organizational changes. Projects are finite in length, usually one-time pieces of work involving a number of activities that must be completed within a given time frame, and often on a fixed budget.
While the very simplest projects can be managed easily by applying common sense and just getting on with things, projects that are more complex need a great deal of planning, and benefit from a formal, disciplined management approach. From making sure that activities will actually meet the specified need, to devising a workable schedule, developing systems for reporting progress, and managing requests for changes – all of these issues require thoughtful consideration. Managing projects well requires a great deal of time, skill, and finesse. There are many sides to project management and this is what makes it so interesting and demanding
Project Planning includes:
Dividing the project into plannable stages When to build the project plan
Who constructs the project plan
Step by step guide to constructing a project plan
Making the project plan visible, getting the project plan used Independent project plan reviews
Getting resource commitments Time recording
Tracking progress against the project plan Revising the project plan during the project
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7.2 SOFTWARE CONFIGURATION MANAGEMENT
Software Configuration Management (SCM) is the task of tracking and controlling changes in the software. Configuration management practices include revision control and the establishment of baselines.Software Configuration Management Software (SCM) is a set of activities that are designed to control change by identifying the work products that are likely to change, establishing relationships among them, defining mechanisms for managing different versions of work products, controlling changes that are imposed, and auditing and reporting on the changes that are made”.
SCM is a best tool to manage change to our software systems. However, even with the best of intentions, software projects continue to fail because of problems that could have been avoided through the use of an SCM tool and appropriate processes. These failures are reflected in poor quality, late delivery, cost overruns, and the incapability to meet customer demands. All these flaws are removed by Software Configuration Management (SCM).
This Software was developed by four developers (Gagandeep, Navdeep, Nitika).We make this project together by putting our full efforts and hard work. We completed this project in six months. We have worked for at least 5 hours in a day. We also have Java classes daily. While making project we follow the stages like Project Planning, Design and Coding, Integration and Testing.
Goals
The goals of SCM are generally:
Configuration identification – Identifying configurations, configuration items
and baselines.
Configuration control – Implementing a controlled change process. This is
usually achieved by setting up a change control board whose primary function is to
approve or reject all change requests that are sent against any baseline.
Configuration status accounting – Recording and reporting all the necessary
information on the status of the development process.
Process management – Ensuring adherence to the organization’s development
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7.3 PROBLEM ANALYSIS
To understand the nature of the system to be built, the system engineer or “Analyst” must understand the information domain for the software, as well as required function, behavior, performance and interfacing. The essential purpose of this phase is to find the need and to define the problem that needs to be solved. In requirement analysis following questions are answered-
1.
What the problem is?
The problem is to develop a Peer to Peer Network which enables the sharing of computer resources and services by direct exchange of information. Accessing these decentralized resources means operating in an environment of unstable and unpredictable IP addresses P2P nodes must operate outside the DNS system and have significant, or total autonomy from central servers.
2. Why we need Peer to Peer Network?
It is a model of communication where every node in the network acts alike.As opposed to the client –Server Model where one provide services and other use the services. A distributed network architecture may be called a P2P network if the participants share a part of their own resources. These shared resources are necessary to provide the service offered by the network. The participants of such a network are both resource providers and resource consumers.
3.
Whether the problem is worth solving or not?
i. All nodes are both clients and server that provide and consume data.
ii. Any peer can initiate a connection.
iii. No centralized data source
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CHAPTER 8
REQUIREMENT ANALYSIS
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8.1 REQUIREMENT ANALYSIS
Requirement Analysis in systems engineering and software engineering, encompasses those tasks that go into determining the needs or conditions to meet for a new or altered product, taking account of the possibly conflicting requirements of the various stakeholders, such as
beneficiaries or users.
Requirement analysis is critical to the success of a development project. Requirements must be documented, actionable, measurable, testable, related to identified business needs or
opportunities, and defined to a level of detail sufficient for system design. Requirements can be functional and non-functional.
Any coherent and reasonable system must have requirements that define what the system is ultimately supposed to do. A requirement is an objective that must be met. Planners cast most requirements in functional terms, leaving design and implementation details to the developers. In this Peer to Peer Network, we implemented this phase of requirements gathering by collecting information from various sources like existing systems and network managers who manage their networks.
Evaluation of the existing system and procedures
We studied the features of various existing Peer to Peer network such as Napster,Gneutlla which helped us in identifying its capabilities, Architecture of p2p, its graphical user interface design, how data is shared and used by the peers.
We tried to answer following questions in requirement gathering phase- Who all can use this software?
How will they use the software?
In which networks is this software successful? How to connect clients through sockets ? How the data will be share by peers? How data packets travel along the network?
These and many more such questions were there while starting the project and all such questions got answered during the requirements’ gathering phase. This produced a nice big list of functionality that the system should provide, which described functions the system will perform.
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Eliciting requirements: the task of communicating with customers and users to determine what their requirements are. This is sometimes also called requirements gathering.
Analyzing requirements: determining whether the stated requirements are unclear, incomplete, ambiguous, or contradictory, and then resolving these issues.
Recording requirements: Requirements might be documented in various forms, such as natural-language documents, use cases, user stories, or process specifications
8.2
Types of Requirements
Customer Requirements
Statements of fact and assumptions that define the expectations of the system in terms of mission objectives, environment, constraints, and measures of effectiveness and suitability (MOE/MOS). The customers are those that perform the eight primary functions of systems engineering, with special emphasis on the operator as the key customer.
Architectural Requirements
Architectural requirements explain what has to be done by identifying the necessary system architecture of a system.
Structural Requirements
Structural requirements explain what has to be done by identifying the necessary structure of a system.
Behavioral Requirements
Behavioral requirements explain what has to be done by identifying the necessary behavior of a system.
Functional Requirements
Functional requirements explain what has to be done by identifying the necessary task, action or activity that must be accomplished. Functional requirements analysis will be used as the toplevel functions for functional analysis.
Non-functional Requirements
Non-functional requirements are requirements that specify criteria that can be used to judge the operation of a system, rather than specific behaviors.
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CHAPTER 9
OVERALL NETWORK
ARCHITECTURE
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OVERALL NETWORK ARCHITECTURE
9.1 Client-Server Model
The client/server model is a computing model that acts as distributed application which partitions tasks or workloads between the providers of a resource or service, called servers, and service requesters, called clients.[1] Often clients and servers communicate over a computer network on separate hardware, but both client and server may reside in the same system. A server machine is a host that is running one or more server programs which share their resources with clients. A client does not share any of its resources, but requests a server's content or service function. Clients therefore initiate communication sessions with servers which await incoming requests.
Figure 9.1 : Schematic clients-server interaction
The interaction between client and server is often described using sequence diagrams. The Unified Modeling Language has support for sequence diagrams.
Specific types of clients include web browsers, email clients The client/server characteristic describes the relationship of cooperating programs in an application. The server component provides a function or service to one or many clients, which initiate requests for such services.
Functions such as email exchange, web access and database access, are built on the client/server model. Users accessing banking services from their computer use a web browser client to send a request to a web server at a bank. That program may in turn forward the request to its own database client program that sends a request to a database server at another bank computer to retrieve the account information. The balance is returned to the bank database client, which in turn serves it back to the web browser client displaying the results to the user. The client–server model has become one of the central ideas of network computing. Many business applications being written today use the client–server model. So do the Internet's main application protocols, such as HTTP, SMTP, Telnet, and DNS and online chat clients. Specific types of servers include
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web servers, ftp servers, application servers, database servers, name servers, mail servers, file servers, print servers, and terminal servers. Most web services are also types of servers.
In a traditional client/server setup, your home PC acts as a client and sends requests to machines-- serversmachines--machines-- somewhere inside the cloud of the Internet to get things done: browsing the web or getting email. In a P2P paradigm, on the other hand, your home PC (for example) may connect, through the Internet, directly to tens or hundreds of other home PCs (or other machines at the 'edge') in order to share information and data.
Some of the issues that need to be handled in such a situation include:
Connectivity: how to find and connect other P2P nodes that are running in the network (unlike traditional servers, they don't have a fixed, known IP address)
Instability: nodes may always be joining and leaving the network (unlike servers-- web, email, etc., which we usually depend on to "be there")
Message routing: how messages should be routed to get from one node to another (where the two nodes may not directly know about each other)
Searching (somewhat related to routing): how to find desired information from the nodes connected to the network
9.1.1 Client / Server Limitations
Scalability is hard to achieve Presents a single point of failure Requires administration
Unused resources at the network edge P2P systems try to address these limitations
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9.2 P2P ARCHITECTURE
Figure 9.2.1 P2P Architecture
Features
All nodes are both clients and servers Provide and consume data
Any node can initiate a connection No centralized data source
“The ultimate form of democracy on the Internet
P2P Network Characteristics
Clients are also servers and routers
Nodes contribute content, storage, memory, CPU Nodes are autonomous (no administrative authority)
Network is dynamic: nodes enter and leave the network “frequently”
Nodes collaborate directly with each other (not through well-known servers) Nodes have widely varying capabilities
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CHAPTER 10
MODULES
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MODULES
.1
Create Main Peer to Peer server
In this module, numbers of clients are connected to the main peer to peer server. In this, P2P server will contain all the information about the connected peer. In this module we have created a one main class P2PServerGUI in which we have two inner classes : p2pserver & client handler.
P2P SERVER WILL CONTAIN ALL THE
INFORMATION ABOUT THE PEER
CLIENT 2
CLIENT 3
CLIENT 4
CLIENT 1
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.2
Create Main Peer 2 Peer Client
In this, Main Clients are created and then connected to the P2P server. P2P server will contains the IP addresses of connected main clients.
If the client will get offline then its IP address wil be remove from P2P sever GUI.
192.168.137.21 192.168.137.78 192.168.137.45 --- Main Client Main Client Main Client Main Client
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.3
Creating Miniserver and Miniclient on Peer to Peer
Connection with
Main Server
Channel for getting
Response from sever
MINI CLIENT - Basically for Connecting Two Another Peers. MINI SERVER - Service for other Peers to Connect.
In this module, we have P2P Main Client and P2P Main Server. Every client is itself a mini
client and mini server.
In mini server there is one miniserver request handler which will use the DataOutput Stream & DataInput Stream.It will help us in searching and downloading the file from other peer.
P2P SERVER (MAIN) Mini Client Mini Server
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.4
Manage Online or Offline user list in Real Time
Connected
Connected
Not Connected
In this module, P2P Main Server contains the list of IP addresses of connected users.P2P server will show the names of the user which are online and connected to the main server & does not contain the names of those user which are offline.
192.168.137.21 192.168.137.21 192.168.137.78 --- --- 192.168.137.78 192.168.137.99
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.5
Sharing Files on P2P Network
P2P Main Client P2P Main Server
P2P or Peer-to-peer file sharing allows users to download media files such as music, movies, and games using a P2P software client that searches for other connected computers. The only requirements for a computer to join peer-to-peer networks are an Internet connection and P2P software
.
1.mp3 2.jpg 2.exe 192.168.137.21 192.168.137.78 --- ---Page | 43
.6
Receive search Request on Server Side
Send search request for any file
(like 1.mp3)
Send search request for any file (like 2.jpg)
P2P Main Server
In this, Client 1 send search request for any file that he /she wants like one.mp3, two.jpg etc. to the P2P main server.
192.168.137.21 192.168.137.21 192.168.137.21 Online Systems 192.168.137.21 192.168.137.78 --- ---
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.7
Search file on Peers and sending Result back
1) 1.) Search 1.mp3
4.) Send list of clients having the file
2.) Do You have 1.mp3 Yes ---> 3.) Do You have 1.mp3 No --->
In this, Client 1 searches for the file like one.mp3 from P2P main server and in response P2P main server sends list of clients having the file.
If the other client will not have the file then message “File not found” will be shown on the side of requesting peer.
If the peer have that specified copy or other related file ,then the files will be displayed on the Jtable. 192.168.137.21 192.168.137.78 192.168.137.99 Online Systems 192.168.137.21 192.168.137.78 --- ---
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.8
Downloading File from other peer
MAIN CLIENT MAIN CLIENT
Connected to mini server
Downloading file from other peer
through Mini server
Downloading file from one peer Uploading file to other peer
Connected Connected
Now Client 1 has the list of peers having searched file. Then Client 1 will get connected to mini server. Client can download file from other peer through mini server. Mini Server will upload file to other peer.
The peer will select the file he/she need and start downloading it.If that file is already existing in their shared folder , miniserver will ask them “file already exist “ do you want to download it and rename it” MINI CLIENT MINI CLIENT P2P MAIN SERVER
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.9
Peers can chat and ask other peers to share files
Send text ( ask for file )
Connected
Send text ( chat text )
To chat we have two clients Client 1 and Client 2 and they are connected to each other. Client 1 send text(ask for file), in response Client 2 send text(chat text file).Client1& Client 2 are connected to P2P server.
In this module we will create a TextArea in our mainclient form .The text of textfield will be move to the selected IP and it will be displayed on other IP textfield.
Main Client 1 Main Client 2
P2P MAIN SERVER
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CHAPTER 11
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11.1 DESIGN PHASE
In systems, design functions and operations are described in detail, including screen layouts, business rules, process diagrams and other documentation. The output of this stage will describe the new system as a collection of modules or subsystems.
The design stage takes as its initial input the requirements identified in the approved requirements document. For each requirement, a set of one or more design elements will be produced as a result of interviews, workshops, and/or prototype efforts. Design elements describe the desired software features in detail, and generally include functional hierarchy diagrams, screen layout diagrams, tables of business rules, business process diagrams, pseudo code, and a complete entity-relationship diagram with a full data dictionary. These design elements are intended to describe the software in sufficient detail that skilled programmers may develop the software with minimal additional input.
Figure 11.1 : Design Phase
Requirements Document DESIGN STAGE Design Document Updated Project Plan &
Schedule
Updated Requirements
Traceability Matrix
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CHAPTER 12
DATA FLOW DIAGRAMS
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12.1 INTRODUCTION
A data-flow diagram (DFD) is a graphical representation of the "flow" of data through an information system. DFDs can also be used for the visualization of data processing.
On a DFD, data items flow from an external data source or an internal data store to an internal data store or an external data sink, via an internal process.A DFD provides no information about the timing or ordering of processes, or about whether processes will operate in sequence or in parallel.
It is common practice to draw a context-level data flow diagram first, which shows the interaction between the system and external agents which act as data sources and data sinks. On the context diagram (also known as the Level 0 DFD) the system's interactions with the outside world are modeled purely in terms of data flows across the system boundary. The context diagram shows the entire system as a single process, and gives no clues as to its internal organization.
This context-level DFD is next "exploded", to produce a Level 1 DFD that shows some of the detail of the system being modeled. The Level 1 DFD shows how the system is divided into sub-systems, each of which deals with one or more of the data flows to or from an external agent, and which together provide all of the functionality of the system as a whole. It also identifies internal data stores that must be present in order for the system to do its job, and shows the flow of data between the various parts of the system.
