Nymble: Blocking Misbehaving Usersin Anonymizing Networks

A Major Project Submitted in Partial Fulfillment of the Requirements for the

degree of Bachelor of Technology in Information Technology

SUBMITTED BY

SANDESH KUMAR

REG.No. 11089E070

S. VIJAY

REG.No. 11089E087

GUIDED BYN. KUMARAN M.Tech.

Assistant ProfessorDepartment of Information Technology

SCSVMV University

DEPARTMENT OF INFORMATION TECHNOLOGYSRI CHANDRASEKHARENDRA SARASWATHI

VISHWA MAHAVIDYALAYAUNIVERSITY

APRIL 2012

Sri Chandrasekharendra Saraswathi Viswa MahaVidyalaya

University Enathur, Kanchipuram – 631 561

BONAFIDE CERTIFICATE

Certified that this Project Entitled Nymble: Blocking Misbehaving Users in

Anonymizing Networks is the bonafied work carried out by Mr. SANDESH

KUMAR Reg.No 11089E070 and Mr. S.VIJAY Reg.No. 11089E087 during the

academic year 2012. It is certified that all the corrections/suggestion indicated for

internal assessment have been incorporated.

N. KUMARAN M.Tech. R. Manickavasagam M.SAssistant Professor Head of DepartmentDepartment of Information Technology Department of Information Technology SCSVMV University SCSVMV University

Submitted for the Project examination held on ___March 2012_____________

Place : Kanchipuram.

ACKNOWLEDGEMENT

The successful completion of my project can be attributed to the combined

efforts made by me and the contribution made in one form or other by the individuals.

First and foremost I thank God Almighty for giving me all strength, courage and

blessings to design and complete this project. I wish to extend my sincere gratitude to

our Head of the Information Technology Department, Mr. R.Manickavasagam. I

also thank him for his sincere help and support. Words fail to thank adequately our

project guide Mr.N.Kumaran who gave me all supports and helped me to clear all

confusions regarding the project. And last but not the least; I thank my family

members and my friends for providing me moral support to achieve my goal.

TABLE OF CONTENTS

Chapter No. Title Page No.

ABSTRACT ILIST OF TABLES IIILIST OF FIGURES IVLIST OF ABBREVIATION V

1. Introduction 1

1.1 Objective 21.2 About the organization 3

2. System Planning and Requirements2.1 System analysis 52.2 Feasibility study 9

2.3 Software and Hardware Requirements 11 2.4 Functional Requirements 12

2.5 Non Functional Requirements 122.6 Pseudo Requirements 122.7 Literature survey 132.8 Modules Description 14

3. System Design

3.1 Data Flow Diagram 173.2 Control Flow Diagram 223.3 Database Design 25

4. System implementation

4.1 Process Specification 274.2 Techniques and Algorithms used 294.3 Sample Coding 304.4 Technology Description 50

5. Reports5.1 Sample Screens 67

6. Testing 77

7. Conclusion 82

8. Scope for further Development 84

9. References 86

1.INTRODUCTION

1.1 OBJECTIVE

Anonymizing networks such as route traffic through independent nodes in

separate administrative domains to hide a client’s IP address. Unfortunately, some

users have misused such networks—under the cover of anonymity, users have

repeatedly defaced popular Web sites such as Wikipedia. Since Web site

administrators cannot blacklist individual malicious users’ IP addresses, they blacklist

the entire anonymizing network.

Such measures eliminate malicious activity through anonymizing networks at the cost

of denying anonymous access to behaving users. In other words, a few “bad apples”

can spoil the fun for all. (This has happened repeatedly with Tor.1) There are several

solutions to this problem, each providing some degree of accountability. In

pseudonymous credential systems users log into Web sites using pseudonyms, which

can be added to a blacklist if a user misbehaves. Unfortunately, this approach results

in pseudonymity for all users, and weakens the anonymity provided by the

anonymizing network.

Anonymous credential systems employ group signatures. Basic group signatures

allow servers to revoke a misbehaving user’s anonymity by complaining to a group

manager. Servers must query the group manager for every authentication, and thus,

lacks scalability. Traceable signatures allow the group manager to release a trapdoor

that allows all signatures generated by a particular user to be traced; such an approach

does not provide the backward unlinkability that we desire, where a user’s accesses

before the complaint remain anonymous. Backward unlinkability allows for what we

call subjective blacklisting, where servers can blacklist users for whatever reason

since the privacy of the blacklisted user is not at risk.

Further, approaches without backward unlinkability need to pay careful attention to

when and why a user must have all their connections linked, and users must worry

about whether their behaviors will be judged fairly. Subjective blacklisting is also

better suited to servers such as Wikipedia, where misbehaviors such as questionable

edits to a Webpage, are hard to define in mathematical terms.

In some systems, misbehavior can indeed be defined precisely. For instance, double

spending of an “e-coin” is considered a misbehavior in anonymous e-cash systems

following which the offending user is deanonymized. Unfortunately, such systems

work for only narrow definitions of misbehavior—it is difficult to map more complex

notions of misbehavior onto “double spending” or related approaches.

Verifier-local revocation (VLR) fixes this shortcoming by requiring the server

(“verifier”)to perform only local updates during revocation. Unfortunately,

VLRrequires heavy computation at the server that is linear in the size of the blacklist.

For example, for a blacklist with 1,000 entries, each authentication would take tens of

seconds,2 a prohibitive cost in practice. In contrast, our scheme takes the server about

one millisecond per authentication, which is several thousand times faster than VLR.

1.2 ABOUT THE ORGANIZATION

Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya, formed under the

aegis of Sri Kanchi Kamakoti Peetam Charitable Trust in 1993, is located in a

sprawling complex of 50 acres at Enathur, at a distance of about 4 Kilometres from

Kanchipuram. The University has a campus in Poonamalle, Chennai, housing an

ayurveda College, research centre and hospital. The University has a unique focus on

integrating traditional knowledge with modern scientific practices with a global

outlook.

2. SYSTEM PLANNING

AND REQUIREMENTS

2.1 PROBLEM DEFINITION

Dynamic accumulators a revocation operation results in a new accumulator

and public parameters for the group, and all other existing users’ credentials must be

updated, making it impractical. Verifier-local revocation (VLR) fixes this

shortcoming by requiring the server (“verifier”) to perform only local updates during

revocation. Unfortunately,VLRrequires heavy computation at the server that is linear

in the size of the blacklist. For example, for a blacklist with 1,000 entries, each

authentication would take tens of seconds,2 a prohibitive cost in practice.

2.2 EXISTING SYSTEMExisting users’ credentials must be updated, making it impractical. Verifier-

local revocation (VLR) fixes this shortcoming by requiring the server (“verifier”) to

perform only local updates during revocation. Unfortunately, VLR requires heavy

computation at the server that is linear in the size of the blacklist.

2.3 LIMITATIONS OF EXISTING SYSTEM

Anonymous authentication, backward unlinkability, subjective blacklisting,

fast authentication speeds, rate-limited anonymous connections, revocation

auditability (where users can verify whether they have been blacklisted), and also

addresses the Sybil attack to make its deployment practical.

2.4 PROPOSED SYSTEMWe present a secure system called Nymble, which provides all the following

properties: anonymous authentication, backward unlinkability, subjective blacklisting,

fast authentication speeds, rate-limited anonymous connections, revocation

auditability (where users can verify whether they have been blacklisted), and also

addresses the Sybil attack to make its deployment practical In Nymble, users acquire

an ordered collection of nymbles, a special type of pseudonym, to connect to

websites. Without additional information, these nymbles are computationally hard to

link,and hence using the stream of nymbles simulates anonymous access to services.

Websites, however, can blacklist users by obtaining a seed for a particular nymble,

allowing them to link future nymbles from the same user — those used before the

complaint remain unlinkable. Servers can therefore blacklist anonymous users without

knowledge of their IP addresses while allowing behaving users to connect

anonymously. Our system ensures that users are aware of their blacklist status before

they present a nymble, and disconnect immediately if they are blacklisted. Although

our work applies to anonymizing networks in general, we consider Tor for purposes

of exposition. In fact, any number of anonymizing networks can rely on the same

Nymble system, blacklisting anonymous users regardless of their anonymizing

network(s) of choice

Fig 2.2.1 overview of the system

• Blacklisting anonymous users. We provide a means by which servers can blacklist

users of an anonymizing network while maintaining their privacy.

• Practical performance. Our protocol makes use of inexpensive symmetric

cryptographic operations to significantly outperform the alternatives.

• Open-source implementation. With the goal of contributing a workable system, we

have built an open source implementation of Nymble, which is publicly available. We

provide performance statistics to show that our system is indeed practical.

2.5 ADVANTAGES OF PROPOSED SYSTEM

We present a secure system called Nymble, which provides all the following

properties: anonymous authentication, backward unlinkability, subjective blacklisting,

fast authentication speeds, rate-limited anonymous connections, revocation auditabi

lity (where users can verify whether they have been blacklisted), and also addresses

the Sybil attack to make its deployment practical In Nymble, users acquire an ordered

collection of nymbles, a special type of pseudonym, to connect to websites. Without

additional information, these nymbles are computationally hard to link,and hence

using the stream of nymbles simulates anonymous access to services.

PROCESS FLOW DIAGRAMS FOR PROPOSED SYSTEM

Fig 2.2.3 architecture of the system design

Website servers

Tor( the onion router)

User login and signup

Pseudo manager

Nymble manager

4. Linking window communication

3. Nimble ticket generation

2. System setup

5. Blacklist update , server registration and complaining

User registration

6. Server access

2.2 FEASIBILITY STUDY

The feasibility of the project is analyzed in this phase and business proposal is put

forth with a very general plan for the project and some cost estimates. During system

analysis the feasibility study of the proposed system is to be carried out. This is to

ensure that the proposed system is not a burden to the company. For feasibility

analysis, some understanding of the major requirements for the system is essential.

Three key considerations involved in the feasibility analysis are

ECONOMICAL FEASIBILITY

TECHNICAL FEASIBILITY

SOCIAL FEASIBILITY

2.2.1 ECONOMICAL FEASIBILITY

This study is carried out to check the economic impact that the system will

have on the organization. The amount of fund that the company can pour into the

research and development of the system is limited. The expenditures must be justified.

Thus the developed system as well within the budget and this was achieved because

most of the technologies used are freely available. Only the customized products had

to be purchased.

2.2.2 TECHNICAL FEASIBILITY

This study is carried out to check the technical feasibility, that is, the

technical requirements of the system. Any system developed must not have a high

demand on the available technical resources. This will lead to high demands on the

available technical resources. This will lead to high demands being placed on the

client. The developed system must have a modest requirement, as only minimal or

null changes are required for implementing this system.

2.3.3 SOCIAL FEASIBILITY

The aspect of study is to check the level of acceptance of the system by the

user. This includes the process of training the user to use the system efficiently. The

user must not feel threatened by the system, instead must accept it as a necessity. The

level of acceptance by the users solely depends on the methods that are employed to

educate the user about the system and to make him familiar with it. His level of

confidence must be raised so that he is also able to make some constructive criticism,

which is welcomed, as he is the final user of the system.

2.3 HARDWARE AND SOFTWARE REQUIREMENTS

2.3.1 HARDWARE REQUIREMENTS

• System : Pentium IV 2.4 GHz.

• Hard Disk : 40 GB.

• Floppy Drive : 1.44 Mb.

• Monitor : 15 VGA Colour.

• Mouse : Logitech.

• Ram : 512 Mb.

2.3.2 SOFTWARE REQUIREMENTS

• Operating system : Windows XP.

• Coding Language : JDK 1.6

• Tools : Eclipse 3.3

2.4 FUNCTIONAL REQUIREMENTS

Functional requirements specify which output file should be produced from

the given file they describe the relationship between the input and output of the

system, for each functional requirement a detailed description of all data inputs and

their source and the range of valid inputs must be specified.

2.5 NON FUNCTIONAL REQUIREMENTS

Describe user-visible aspects of the system that are not directly related with

the functional behavior of the system. Non-Functional requirements include

quantitative constraints, such as response time (i.e. how fast the system reacts to

user commands.) or accuracy ((.e. how precise are the systems numerical answers.)

2.6 PSEUDO REQUIREMENTSThe client that restricts the implementation of the system imposes these

requirements. Typical pseudo requirements are the implementation language and the

platform on which the system is to be implemented. These have usually no direct

effect on the users view of the system.

2.7 LITERATURE SURVEY

Literature survey is the most important step in software development process.

Before developing the tool it is necessary to determine the time factor, economy n

company strength. Once these things r satisfied, ten next steps are to determine which

operating system and language can be used for developing the tool. Once the

programmers start building the tool the programmers need lot of external support.

This support can be obtained from senior programmers, from book or from websites.

Before building the system the above consideration r taken into account for

developing the proposed system.

To limit the number of identities a user can obtain (called the Sybil attack

[19]), the Nymble system binds nymbles to resources that are sufficiently difficult to

obtain in great numbers. For example, we have used IP addresses as the resource in

our implementation, but our scheme generalizes to other resources such as email

addresses, identity certificates, and trusted hardware. We address the practical issues

related with resource-based blocking in Section 8, and suggest other alternatives for

resources. We do not claim to solve the Sybil attack. This problem is faced by any

credential system [19], [27], and we suggest some promising approaches based on

resource-based blocking since we aim to create a real-world deployment. The user

must first contact the Pseudonym Manager (PM) and demonstrate control over a

resource; for IP-address blocking, the user must connect to the PM directly (i.e., not

through a known anonymizing network), as shown.

We assume the PM has knowledge about Tor routers, for example, and can

ensure that users are communicating with it directly.6 Pseudonyms are

deterministically chosen based on the controlled resource, ensuring that the same

pseudonym is always issued for the same resource. Note that the user does not

disclose what server he or she intends to connect to, and the PM’s duties are limited to

mapping IP addresses (or other resources) to pseudonyms. As we will explain, the

user contacts the PM only once per linkability window (e.g., once a day).

2.8 MODULES DESCRIPTION

2.9.1. NYMBLE MANAGERServers can therefore blacklist anonymous users without knowledge of their IP

addresses while allowing behaving users to connect anonymously. Our system

ensures that users are aware of their blacklist status before they present a nymble, and

disconnect immediately if they are blacklisted. Although our work applies to

anonymizing networks in general, we consider Tor for purposes of exposition. In fact,

any number of anonymizing networks can rely on the same Nymble system,

blacklisting anonymous users regardless of their anonymizing network(s) of choice.

2.9.2. PSEUDONYM MANAGERThe user must first contact the Pseudonym Manager (PM) and demonstrate

control over a resource; for IP-address blocking, the user must connect to the PM

directly (i.e., not through a known anonymizing network), ensuring that the same

pseudonym is always issued for the same resource.

2.9.3. BLACKLISTING A USERUsers who make use of anonymizing networks expect their connections to be

anonymous. If a server obtains a seed for that user, however, it can link that user’s

subsequent connections. It is of utmost importance, then, that users be notified of their

blacklist status before they present a nymble ticket to a server. In our system, the user

can download the server’s blacklist and verify her status. If blacklisted, the user

disconnects immediately.

IP-address blocking employed by Internet services. There are, however, some

inherent limitations to using IP addresses as the scarce resource. If a user can obtain

multiple addresses she can circumvent both nymble-based and regular IP-address

blocking. Subnet-based blocking alleviates this problem, and while it is possible to

modify our system to support subnet-based blocking, new privacy challenges emerge;

a more thorough description is left for future work.

2.9.4. NYMBLE-AUTHENTICATED CONNECTIONBlacklistability assures that any honest server can indeed block misbehaving

users. Specifically, if an honest server complains about a user that misbehaved in the

current linkability window, the complaint will be successful and the user will not be

able to “nymble-connect,” i.e., establish a Nymble-authenticated connection, to the

server successfully in subsequent time periods (following the time of complaint) of

that linkability window.

Rate-limiting assures any honest server that no user can successfully nymble-

connect to it more than once within any single time period. Non-frameability

guarantees that any honest user who is legitimate according to an honest server can

nymble-connect to that server. This prevents an attacker from framing a legitimate

honest user, e.g., by getting the user blacklisted for someone else’s misbehavior. This

property assumes each user has a single unique identity.

When IP addresses are used as the identity, it is possible for a user to “frame” an

honest user who later obtains the same IP address. Non-frameability holds true only

against attackers with different identities (IP addresses).

A user is legitimate according to a server if she has not been blacklisted by the

server, and has not exceeded the rate limit of establishing Nymble-connections.

Honest servers must be able to differentiate between legitimate and illegitimate users.

Anonymity protects the anonymity of honest users, regardless of their

legitimacy according to the (possibly corrupt) server; the server cannot learn any more

information beyond whether the user behind (an attempt to make) a nymble-

connection is legitimate or illegitimate

3.SYSTEM DESIGN

3.1 Data Flow Diagram

The DFD is also called as bubble chart. It is a simple graphical formalism that

can be used to represent a system in terms of the input data to the system,

various processing carried out on these data, and the output data is generated

by the system

The data flow diagram (DFD) is one of the most important modeling tools. It

is used to model the system components. These components are the system

process, the data used by the process, an external entity that interacts with the

system and the information flows in the system.

DFD shows how the information moves through the system and how it is

modified by a series of transformations. It is a graphical technique that depicts

information flow and the transformations that are applied as data moves from

input to output.

DFD is also known as bubble chart. A DFD may be used to represent a system

at any level of abstraction. DFD may be partitioned into levels that represent

increasing information flow and functional detail.

NOTATION

SOURCE OR DESTINATION OF DATAExternal sources or destinations, which may be people or organizations or

other entities.

DATA SOURCE Here the data referenced by a process is stored and retrieved.

PROCESSPeople, procedures or devices that produce data. The physical component is

not identified.

DATA FLOWData moves in a specific direction from an origin to a destination. The data flow is

a “packet” of data.

MODELING RULES

There are several common modeling rules when creating DFDs:

1. All processes must have at least one data flow in and one data flow out.

2. All processes should modify the incoming data, producing new forms of

outgoing data.

3. Each data store must be involved with at least one data flow.

4. Each external entity must be involved with at least one data flow.

A data flow must be attached to at least one process.

DFD LEVEL-0

A level 0 DFD, also called a fundamental system model or a context model,

represents the entire software element as a single bubble with input and output data

indicated by incoming and outgoing arrows, respectively. Additional processes

(bubbles) and information flow paths are represented as the level 0 DFD is partitioned

to reveal more detail.

DFD has the following operations:

Shows the system’s major processes, data flows, and data stores at a high level of

abstraction

When the Context Diagram is expanded into DFDlevel-0, all the connections that

flow into and out of process 0 needs to be retained.

The context-level DFD is next "exploded", to produce a Level 0 DFD that shows

some of the detail of the system being modeled. The Level 0 DFD shows how the

system is divided into sub-systems (processes), 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.

Fig 3.1.1 dfd level 0

user

server

Nimble serverPseudo manager

DFD LEVEL-1

A level 1 DFD might contain five or six bubbles with interconnecting arrows.

Each of the processes represented at level 1 is a sub-function of the overall system

depicted in the context model. Each of the bubbles may be refined or layered to depict

more details. The level 1 diagram shows the main functional areas of the system

under investigation. As with the context diagram, any system under investigation

should be represented by only one level 1 diagram. There is no formula that can be

applied in deciding what is, and what is not, a level 1 process. Level 1 process should

describe only the main functional areas of the system, and you should avoid the

temptation of including lower level processes on this diagram. As a general rule no

business process diagram should contain more than 12 process boxes. The level 1

diagram is surrounded by the outline of a process box that represents the boundaries

of the system. Because the level 1 diagram depicts the whole of the system under

investigation, it can be difficult to know where to start.

Fig 3.1.2 Dfd level 1

Sign in

SignupWebsite Server

database

Authentication

File availability

Nymble server

Pseudo manager

File selection

Servers communicatio

n (nymble ticket and

linking window)

Home page

Select a file

Enter key

Check for file

Blocking ip address Server

availability

User view

List of block ip address Blacklist

Refreshment

Nymble ticket

users

3.2 CONTROL FLOW DIAGRAM

A control flow diagram can consist of a subdivision to show sequential steps,

with if-then-else conditions, repetition, and/or case conditions. Suitably annotated

geometrical figures are used to represent operations, data, or equipment, and arrows

are used to indicate the sequential flow from one to another.

There are several types of control flow diagrams, for example:

Change control flow diagram, used in project management

Configuration decision control flow diagram, used in configuration

management

Process control flow diagram, used in process management

Quality control flow diagram, used in quality control.

In software and systems development control flow diagrams can be used in control

flow analysis, data flow analysis, algorithm analysis, and simulation. Control and data

flow analysis are most applicable for real time and data driven systems. These flow

analyses transform logic and data requirements text into graphic flows which are

easier to analyze than the text. PERT, state transition, and transaction diagrams are

examples of control flow diagrams.

Types of Control Flow Diagrams:-

1. Process Control Flow Diagram

A flow diagram can be developed for the process control system for each

critical activity. Process control is normally a closed cycle in which a sensor provides

information to a process control software application through a communications

system. The application determines if the sensor information is within the

predetermined (or calculated) data parameters and constraints. The results of this

comparison are fed to an actuator, which controls the critical component. This

feedback may control the component electronically or may indicate the need for a

manual action.

This closed-cycle process has many checks and balances to ensure that it stays

safe. The investigation of how the process control can be subverted is likely to be

extensive because all or part of the process control may be oral instructions to an

individual monitoring the process. It may be fully computer controlled and automated,

or it may be a hybrid in which only the sensor is automated and the action requires

manual intervention. Further, some process control systems may use prior generations

of hardware and software, while others are state of the art.

2. Performance seeking control flow diagram

The figure presents an example of a performance seeking control flow

diagram of the algorithm. The control law consists of estimation, modeling, and

optimization processes. In the Kalman filter estimator, the inputs, outputs, and

residuals were recorded. At the compact propulsion system modeling stage, all the

estimated inlet and engine parameters were recorded.[1]

In addition to temperatures, pressures, and control positions, such estimated

parameters as stall margins, thrust, and drag components were recorded. In the

optimization phase, the operating condition constraints, optimal solution, and linear

programming health status condition codes were recorded. Finally, the actual

commands that were sent to the engine through the DEEC were recorded. dfd(data

float diagam)is network manen ment system that is good.

Fig3.2.1 Cfd lavel 1

Transfer of block ip addresses

User authentication

users

Sign- in

Sign-up

Website Server

database

Authentication

File availability

File selection

Servers communication

Home page

Select a file

Enter key

Check for file

User view

Selection of file

Register a server to the nimble manager

Nymble server

Pseudo manager Blocking ip

address Server availability

List of block ip address Blacklist

Refreshment

Nymble ticket

Refreshing a blacklist

3.3 DATA BASE DESIGN3.3.1 address database

3.3.2 login database

LOGIN

User pass s_code age gen phone address mobileno

User user user 21male 453454 chennai 9953452922

3.3.3 resource database

RESOURCES

files fakefiles op allowedip url

bbb.txt bb false 192.168.1.55 bbb.com

nymble.txt ny false 192.168.1.55 www.nymble.com

3.3.4 server database

Server

SerName Key ip

Nimble nymble 192.168.100.77

Server server 192.168.1.66

ADDRESS

IPADDRESS

192.168.100.57

123.87.100.23

192.168.100.78

192.168.1.55

4. SYSTEM IMPLEMEN-TATION

4.1 PROCESS SPECIFICATION

4.1.1 INPUT DESIGN

The input design is the link between the information system and the user. It

comprises the developing specification and procedures for data preparation and those

steps are necessary to put transaction data in to a usable form for processing can be

achieved by inspecting the computer to read data from a written or printed document

or it can occur by having people keying the data directly into the system. The design

of input focuses on controlling the amount of input required, controlling the errors,

avoiding delay, avoiding extra steps and keeping the process simple. The input is

designed in such a way so that it provides security and ease of use with retaining the

privacy. Input Design considered the following things:

What data should be given as input?

How the data should be arranged or coded?

The dialog to guide the operating personnel in providing input.

Methods for preparing input validations and steps to follow when error

occur.

4.1.2 OBJECTIVES

1. Input Design is the process of converting a user-oriented description of the input

into a computer-based system. This design is important to avoid errors in the data

input process and show the correct direction to the management for getting correct

information from the computerized system.

2. It is achieved by creating user-friendly screens for the data entry to handle large

volume of data. The goal of designing input is to make data entry easier and to be free

from errors. The data entry screen is designed in such a way that all the data

manipulates can be performed. It also provides record viewing facilities.

3.When the data is entered it will check for its validity. Data can be entered with the

help of screens. Appropriate messages are provided as when needed so that the user

will not be in maize of instant. Thus the objective of input design is to create an input

layout that is easy to follow

4.1.3 OUTPUT DESIGN

A quality output is one, which meets the requirements of the end user and

presents the information clearly. In any system results of processing are

communicated to the users and to other system through outputs. In output design it is

determined how the information is to be displaced for immediate need and also the

hard copy output. It is the most important and direct source information to the user.

Efficient and intelligent output design improves the system’s relationship to help user

decision-making.

1. Designing computer output should proceed in an organized, well thought out

manner; the right output must be developed while ensuring that each output element is

designed so that people will find the system can use easily and effectively. When

analysis design computer output, they should Identify the specific output that is

needed to meet the requirements.

2.Select methods for presenting information.

3.Create document, report, or other formats that contain information produced by the

system.

The output form of an information system should accomplish one or more of the

following objectives.

Convey information about past activities, current status or projections of the

Future.

Signal important events, opportunities, problems, or warnings.

Trigger an action.

Confirm an action.

4.2 TECHNIQUES AND ALGORITHM USED

Blacklisting anonymous users

We provide a means by which servers can blacklist users of an anonymizing

network while maintaining their privacy.

Practical performance:

Our protocol makes use of inexpensive symmetric cryptographic operations to

significantly outperform the alternatives.

Open-source implementation:

With the goal of contributing a workable system, we have built an open-source

implementation of Nymble, which is publicly available.5 We provide performance

statistics to show that our system is indeed practical.

Algorithm 3. NMCreateCredential

Input: ðpnym; sid;wÞ 2 P _H_NN

Persistent state: nmState 2 SN

Output: cred 2 D

1: Extract macKeyNS; macKeyN; seedKeyN; encKeyN from

keys in nmState

2: seed0 :¼ fðMacðpnymksidkw; seedKeyNÞÞ

3: nymble_ :¼ gðseed0Þ

4: for t from 1 to L do

5: seedt :¼ fðseedt_1Þ

6: nymblet :¼ gðseedtÞ

7: ctxtt :¼ Enc:Encryptðnymble_kseedt; encKeyNÞ

8: ticket0

t :¼ sidktkwknymbletkctxtt

9: macN;t :¼ MA:Macðticket0

t; macKeyNÞ

10: macNS;t :¼ MA:Macðticket0

tkmacN;t; macKeyNSÞ

11: tickets½t_ :¼ ðt; nymblet; ctxtt; macN;t; macNS;tÞ

12: return cred :¼ ðnymble_; ticketsÞ

4.3 Sample codingNymbleServer

import javax.swing.*;import java.awt.*;import java.awt.event.*;import java.io.*;import java.net.*;import java.util.*;import javax.swing.event.*;import java.sql.*;

class NymbleServer extends JFrame {

JLabel jl1; JLabel jl2; JButton jb1; JButton jb2; JTextField jt1; JPasswordField jt2; String msg=""; Container c; ImageIcon ii; ImageIcon i2; JLabel jl4; JLabel jl6; String str=""; String pass=""; String path=""; String coreaddr=""; String core=""; String nextcore=""; String dest=""; String dest1=""; File f;

File fgs; Vector v = new Vector();

NymbleServer()

{ jl1=new JLabel("Nymble Server Name "); jl2=new JLabel("Server Key "); jb1=new JButton("Send"); jb2=new JButton("Reset"); jt1=new JTextField(10); jt2=new JPasswordField(10); ii=new ImageIcon("nymbleserver.png"); i2=new ImageIcon("nymbleserver1.PNG"); jl4=new JLabel(ii); jl6=new JLabel(i2); c = getContentPane();

c.setLayout(null); c.setBackground(new Color(0,0,120)); c.show(); c.add(jl1); c.add(jt1); c.add(jl2); c.add(jb1); c.add(jb2); c.add(jl4); c.add(jl6); c.add(jt2); addWindowListener(new java.awt.event.WindowAdapter() {

public void windowClosing(java.awt.event.WindowEvent evt) { exitForm(evt); } });

jl4.setBounds(30,20,728,68); jl1.setBounds(20,110,200,25); jt1.setBounds(150,110,100,25); jl2.setBounds(50,145,200,25);

jt2.setBounds(150,145,100,25); jb1.setBounds(70,235,100,25); jb2.setBounds(180,235,100,25); jl6.setBounds(300,105,485,309); setSize(800,500); setVisible(true); setTitle("Server");

jb1.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent ae){

try { if(!jt1.getText().equals("") && !jt2.getText().equals("")){

JOptionPane.showMessageDialog (null, "Authorised User", "Login Seccess", JOptionPane.INFORMATION_MESSAGE);

VerifAdminLogin();

} else JOptionPane.showMessageDialog((Component) null,

"Invalid password. Please try again. ", "Login Error", JOptionPane.INFORMATION_MESSAGE);

}catch(Exception e) { System.out.println(e);}

}});

jb2.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent ae){jt1.setText("");jt2.setText("");} });

} private void exitForm(java.awt.event.WindowEvent evt) {//GEN-FIRST:event_exitForm dispose(); }

public static void main(String a[])

{ new FileOpen();

} void VerifAdminLogin()

{Connection con=null;String url="jdbc:odbc:nymble";Statement st=null;

try {

String val1=jt1.getText(); val1 = val1.trim(); String val2 =

(String)jt2.getText(); val2 = val2.trim();

Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

con=DriverManager.getConnection(url);

st = con.createStatement();

ResultSet rs=st.executeQuery("Select Key from Server where SerName='"+val1+"'");

while(rs.next()){String user = rs.getString(1);

boolean b=user.equals(val2);

if(b){

new Server().show();}

else{

JOptionPane.showMessageDialog((Component) null, "Invalid password. Please try again. ", "Login Error", JOptionPane.INFORMATION_MESSAGE);

jt1.setText("");jt2.requestFocus();

}}

} catch(SQLException ex) { System.out.println("Unable to access the database"); } catch(ClassNotFoundException ex) { System.out.println("Class not found"); } catch(Exception ex) {

System.out.println("Exception raised is:"+ex); } finally { con=null; }

}

}

PseudonymManager

import java.awt.*;import java.io.*;import java.util.Vector;

public class PseudonymManager extends javax.swing.JFrame { public PseudonymManager() { initComponents(); } private void initComponents() { jPanel1 = new javax.swing.JPanel(); jLabel1 = new javax.swing.JLabel(); download = new javax.swing.JButton(); save = new javax.swing.JButton(); jLabel2 = new javax.swing.JLabel();

getContentPane().setLayout(null);getContentPane().setBackground(new java.awt.Color(104, 174,

254));

setBackground(new java.awt.Color(0, 204, 204)); addWindowListener(new java.awt.event.WindowAdapter() { public void windowClosing(java.awt.event.WindowEvent evt) { exitForm(evt); } });

jPanel1.setLayout(null);jPanel1.setBackground(new java.awt.Color(104, 174, 254));

jLabel1.setFont(new java.awt.Font("Arial", 0, 25)); jLabel1.setText(""); //jPanel1.add(jLabel1); jLabel1.setBounds(200, 10, 480, 40);

download.setBackground(new java.awt.Color(204, 204, 254)); download.setFont(new java.awt.Font("Arial", 0, 18)); download.setText("Start Pseudonym Manager"); download.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { downloadActionPerformed(evt);

} });

jPanel1.add(download); download.setBounds(200, 100, 320, 50);

getContentPane().add(jPanel1); jPanel1.setBounds(0, 70, 740, 200);

save.setBackground(new java.awt.Color(204, 174, 254)); save.setFont(new java.awt.Font("Arial", 0, 18)); save.setText("Stop Pseudonym Manager"); save.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { saveActionPerformed(evt); } });

getContentPane().add(save); save.setBounds(200, 290, 320, 50);

jLabel2.setFont(new Font("Arial", 0, 25));

jLabel2.setForeground(new java.awt.Color(222,20, 202));jLabel2.setBackground(new java.awt.Color(114, 74, 54));

jLabel2.setText("Pseudonym Manager"); getContentPane().add(jLabel2); jLabel2.setBounds(250, 30, 270, 40);

pack();setTitle("Nymble_Pseudonym Manager");setSize(800,600);

}

private void saveActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_saveActionPerformed Runtime r = Runtime.getRuntime();Process p = null;String cmd = "../nymble/shutdown.bat";try {p = r.exec(cmd);

p.waitFor();

} catch (Exception e) {System.out.println("error executing " + cmd);}System.out.println(cmd + " returned " + p.exitValue()); } private void downloadActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_downloadActionPerformed

Runtime r = Runtime.getRuntime();Process p = null;String cmd = "../nymble/startup.bat";try {p = r.exec(cmd);

p.waitFor();

} catch (Exception e) {System.out.println("error executing " + cmd);}System.out.println(cmd + " returned " + p.exitValue()); }

private void browserActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_downloadActionPerformed try {

} catch (Exception e) {System.out.println("error executing browser " + evt);} }

private void exitForm(java.awt.event.WindowEvent evt) {//GEN-FIRST:event_exitForm System.exit(0); }

public static void main(String args[]) { new PseudonymManager().show(); } private javax.swing.JButton download; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel2; private javax.swing.JPanel jPanel1; private javax.swing.JButton save;}

PasswordGeneratorimport java.util.ArrayList;import java.util.Collections;import java.util.List;import java.util.Random;

public class PasswordGenerator {

char numberChars[] = "0123456789".toCharArray();

char lowerChars[] = "abcdefghijklmnopqrstuvwxyz".toCharArray();

char upperChars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();

char otherSpecialChars[] = "`~!@#$%^&*()-_=+[{]}\\|;:'\",<.>/?".toCharArray();

List <Integer>listForLengthOfPassword = new ArrayList<Integer>();

Random random = new Random();

List <Character>finalpasswordList;

public PasswordGenerator(){

listForLengthOfPassword.add(1);listForLengthOfPassword.add(2);listForLengthOfPassword.add(2);listForLengthOfPassword.add(3);}

public String getPassword(){

Collections.shuffle(listForLengthOfPassword);finalpasswordList = new ArrayList<Character>();

for(int t=0;t<listForLengthOfPassword.size();t++){

int numberOfCharPerArray = listForLengthOfPassword.get(t);for(int z=0;z<numberOfCharPerArray;z++){

if(t == 0){

finalpasswordList.add(numberChars[random.nextInt(10)]);}else if(t == 1){

finalpasswordList.add(lowerChars[random.nextInt(26)]);}else if(t == 2){

finalpasswordList.add(upperChars[random.nextInt(26)]);}

else if(t == 3){

finalpasswordList.add(otherSpecialChars[random.nextInt(32)]);}

}//end for

}//end for

String password = new String();Collections.shuffle(finalpasswordList);for(int s=0;s<finalpasswordList.size();s++){

password += finalpasswordList.get(s);}return password;}

public static void main(String args[]){

PasswordGenerator passwordGenerator = new PasswordGenerator();

//for(int u=0; u<1000; u++){

System.out.println(passwordGenerator.getPassword());}}

}

Loginimport java.rmi.*;import java.rmi.server.*;import java.net.*;import java.io.*;import javax.swing.*;import java.awt.event.*;import java.lang.*;import java.awt.*;import javax.swing.filechooser.FileSystemView;import java.util.StringTokenizer;import java.net.InetAddress;import java.rmi.Naming;import java.util.Date;import java.util.Vector;import java.util.Random;public class Login extends javax.swing.JFrame {

RMISIntf ref; JOptionPane op; Vector v= new Vector(2); String sss=null;

static String username;

/** Creates new form Login */

public Login() { initComponents();

} private void initComponents()

{

jPan = new javax.swing.JPanel();

jLabel1 = new javax.swing.JLabel(); user = new javax.swing.JTextField(); jLabel2 = new javax.swing.JLabel(); submit = new javax.swing.JButton(); reset = new javax.swing.JButton(); exit = new javax.swing.JButton(); pass = new javax.swing.JPasswordField(); jLabel3 = new javax.swing.JLabel(); op=new JOptionPane(); getContentPane().setLayout(null);

jPanel1 = new javax.swing.JPanel(); listres = new javax.swing.JList(); jLab = new javax.swing.JLabel(); download = new javax.swing.JButton(); resArea = new TextArea(); save = new javax.swing.JButton();

getContentPane().setLayout(null);getContentPane().setBackground(new

Color(200,40,50));

addWindowListener(new java.awt.event.WindowAdapter() { public void

windowClosing(java.awt.event.WindowEvent evt) {

exitForm(evt);

} });

jPan.setLayout(null);

jPan.setBackground(new java.awt.Color(200, 113, 181)); jPan.setBorder(new javax.swing.border.EtchedBorder()); jLab.setFont(new java.awt.Font("Arial", 0, 14)); jLab.setText("User ID:"); jPan.add(jLab); jLab.setBounds(40, 40, 90, 30);

jPan.add(user); user.setBounds(140, 40, 100, 30);

jLabel2.setFont(new java.awt.Font("Arial", 0, 14)); jLabel2.setText("Password:"); jPan.add(jLabel2);

jLabel2.setBounds(40, 90, 90, 30);

submit.setBackground(new java.awt.Color(204, 204, 255)); submit.setFont(new java.awt.Font("Arial", 0, 14)); submit.setForeground(new java.awt.Color(0, 0, 153)); submit.setText("Submit");

submit.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent

evt) { submitActionPerformed(evt);

} });

jPan.add(submit); submit.setBounds(20, 150, 80, 27);

reset.setBackground(new java.awt.Color(204, 204, 255)); reset.setFont(new java.awt.Font("Arial", 0, 14)); reset.setForeground(new java.awt.Color(0, 0, 153)); reset.setLabel("Reset");

reset.addActionListener(new java.awt.event.ActionListener() { public void

actionPerformed(java.awt.event.ActionEvent evt) {

resetActionPerformed(evt); } });

jPan.add(reset); reset.setBounds(120, 150, 80, 27);

exit.setBackground(new java.awt.Color(204, 204, 255)); exit.setFont(new java.awt.Font("Arial", 0, 14)); exit.setForeground(new java.awt.Color(0, 0, 153)); exit.setLabel("Exit"); exit.addActionListener(new java.awt.event.ActionListener()

{ public void

actionPerformed(java.awt.event.ActionEvent evt) {

exitActionPerformed(evt); }

});

jPan.add(exit); exit.setBounds(220, 150, 70, 27);

jPan.add(pass); pass.setBounds(140, 91, 100, 30);

getContentPane().add(jPan); jPan.setBounds(250, 140, 320, 200);

jLabel3.setFont(new java.awt.Font("Arial", 0, 24)); jLabel3.setForeground(new java.awt.Color(255, 255, 255)); jLabel3.setText("Nymble: Blocking Misbehaving Users in

Anonymizing Networks");jLabel3.setFont(new java.awt.Font("Arial", 0, 18));

getContentPane().add(jLabel3); jLabel3.setBounds(100, 30, 570, 30);

pack();

jPanel1.setLayout(null);

jPanel1.setBorder(new javax.swing.border.EtchedBorder()); listres.setBorder(new

javax.swing.border.SoftBevelBorder(javax.swing.border.BevelBorder.LOWERED));

jPanel1.add(listres); listres.setBounds(10, 60, 150, 220);

jLabel1.setFont(new java.awt.Font("Arial", 0, 15)); jLabel1.setText("Resources Available:"); jPanel1.add(jLabel1); jLabel1.setBounds(10, 10, 180, 40);

download.setBackground(new java.awt.Color(204, 204, 254)); download.setFont(new java.awt.Font("Arial", 0, 15)); download.setText("Access File..");

download.addActionListener(new java.awt.event.ActionListener() { public void

actionPerformed(java.awt.event.ActionEvent evt) { downloadActionPerformed(evt);

} });

jPanel1.add(download); download.setBounds(180, 60, 140, 27);

getContentPane().add(jPanel1); jPanel1.setBounds(20, 70, 340, 300);

getContentPane().add(resArea); resArea.setBounds(400, 90, 240, 250);

save.setBackground(new java.awt.Color(204, 204, 254)); save.setFont(new java.awt.Font("Arial", 0, 15)); save.setText("Save"); save.addActionListener(new java.awt.event.ActionListener()

{ public void

actionPerformed(java.awt.event.ActionEvent evt) {

saveActionPerformed(evt);

} });

getContentPane().add(save); save.setBounds(470, 370, 70, 27); resArea.setVisible(false); save.setVisible(false);

jPanel1.setVisible(false); jPanel1.setBackground(new java.awt.Color(0, 204, 204));

}//GEN-END:initComponents

private void exitActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_exitActionPerformed

System.exit(0); }

private void resetActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_resetActionPerformed

user.setText("");

pass.setText(""); }

private void submitActionPerformed(java.awt.event.ActionEvent evt) {try{

ref= (RMISIntf)Naming.lookup("rmi://"+"192.168.1.55"+"/RMIServer");

//System.out.println(ref.res("sdsd","dsa"));

if(user.getText().trim().equals("")){ op.showConfirmDialog(this,"Enter The User

Name","Alert",JOptionPane.DEFAULT_OPTION,JOptionPane.ERROR_MESSAGE);

user.grabFocus();}

else{

if(pass.getText().trim().equals("")) {

op.showConfirmDialog(this,"Enter The PassWord","Alert",JOptionPane.DEFAULT_OPTION,JOptionPane.ERROR_MESSAGE);

pass.grabFocus(); }

else{

InetAddress Address = InetAddress.getLocalHost();

String c =Address.getHostAddress();ref=

(RMISIntf)Naming.lookup("rmi://"+"192.168.1.55"+"/RMIServer");String

ss=ref.CliDet(user.getText(),pass.getText(),c);if(ss.equals("notok")){

op.showConfirmDialog(this,"UnAuthorised User","Alert",JOptionPane.DEFAULT_OPTION,JOptionPane.ERROR_MESSAGE);

user.grabFocus();}

else

{

username=user.getText();String key=(String)JOptionPane.showInputDialog(this,"Enter your Key:");ref=(RMISIntf)Naming.lookup("rmi://"+"192.168.1.55"+"/RMIServer");String status=ref.CliDet_key(user.getText(),key);

if(status.equals("ok")){

username=user.getText();//getContentPane().remove(jPan);//.visible(false);jPan.setVisible(false);jPanel1.setVisible(true);resArea.setVisible(true);save.setVisible(true);StringTokenizer token=new StringTokenizer(ss,";");while(token.hasMoreTokens()){String nextToken = token.nextToken();v.addElement(nextToken);System.out.println(nextToken);}listres.setListData(v);}///inner if

else{op.showConfirmDialog(this,"UnAuthorised

User","Alert",JOptionPane.DEFAULT_OPTION,JOptionPane.ERROR_MESSAGE);

user.grabFocus();}

}

}

}

}catch(Exception e){System.out.println(e);}

}

private void downloadActionPerformed(java.awt.event.ActionEvent evt) {

sss=(String)listres.getSelectedValue(); System.out.println(sss);

int ch=0;try{

InetAddress Address = InetAddress.getLocalHost();String c =Address.getHostAddress();/////////////////////////////////////////////////////

String aa[]=new String[4];ref=

(RMISIntf)Naming.lookup("rmi://"+"192.168.1.55"+"/RMIServer");/////////////////////////String chh=ref.checkipp(c,sss);StringTokenizer st=new StringTokenizer(chh,";");String ipp=null;String opp=null;//while(st.hasMoreTokens()) {

ipp=st.nextToken();System.out.println(ipp+"hai");

opp=st.nextToken();System.out.println(opp);

//}

String optiontest="null";if(ipp.equals("ok")||opp.equals("true")){optiontest="true";

String a=(String)JOptionPane.showInputDialog(this,"Enter your password:");

aa[0]=a;

a=(String)JOptionPane.showInputDialog(this,"Enter your correct password:");

aa[1]=a;

a=(String)JOptionPane.showInputDialog(this,"Enter correct password:");

aa[2]=a;System.out.println(aa[0]+aa[1]);aa[3]=new Date().toString();

ref.store(aa,c,username,sss);

JOptionPane.showMessageDialog (null, "IP Blocked & you are Misbehaving User &you Can't Access Nymble web Page & Cant downlod the file", "you Can't Access Nymble web Page", JOptionPane.ERROR_MESSAGE);

}/////////change

String ssss=ref.res(sss,c,optiontest);/********File ss=ref.res(sss,c,);

//File file = new File(ss); FileInputStream in = new FileInputStream(ss); int i = in.available();

char st[]=new char[i];int j =0; while((ch=in.read())!=-1)

{st[j] = (char) ch;j++;

} String str=new String(st);

resArea.setText(str);***********/

System.out.println("new "+ssss); resArea.setText(ssss);Logged1 l1=new Logged1();

l1.show();

} catch(Exception e) { System.out.println(e); }

}

private void saveActionPerformed(java.awt.event.ActionEvent evt) {

//GEN-FIRST:event_saveActionPerformed

try {FileDialog fd=new FileDialog(this,"File Store",

FileDialog.SAVE);fd.setVisible(true);String f= fd.getFile();fd.setFile(f); // Filename filterfd.setDirectory("."); // Current directory

//fd.show();FileOutputStream out=new FileOutputStream(f);String s=resArea.getText();System.out.println(s);byte b[]=s.getBytes();out.write(b);

} catch(Exception e){System.out.println(e);}

} /** Exit the Application */

private void exitForm(java.awt.event.WindowEvent evt) {//GEN-FIRST:event_exitForm System.exit(0);

} /** * @param args the command line arguments */ public static void main(String args[]) {

JFrame jf1=new Login(); jf1.setResizable(false); jf1.setSize(680,500); jf1.setTitle("Nymble: User Login");jf1.show();

} // Variables declaration - do not modify//GEN-BEGIN:variables private javax.swing.JButton exit; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel2; private javax.swing.JLabel jLabel3; private javax.swing.JPanel jPan; private javax.swing.JPasswordField pass; private javax.swing.JButton reset; private javax.swing.JButton submit; private javax.swing.JTextField user; private javax.swing.JButton download; private javax.swing.JLabel jLab; private javax.swing.JPanel jPanel1; private javax.swing.JList listres; private java.awt.TextArea resArea;

private javax.swing.JButton save;

// End of variables declaration//GEN-END:variables }

4.4 TECHNOLOGY DESCRIPTION

JAVA TECHNOLOGY

Java technology is both a programming language and a platform.

The Java Programming LanguageThe Java programming language is a high-level language that can be

characterized by all of the following buzzwords:

Simple

Architecture neutral

Object oriented

Portable

Distributed

High performance

Interpreted

Multithreaded

Robust

Dynamic

Secure

With most programming languages, you either compile or interpret a program so that

you can run it on your computer. The Java programming language is unusual in that a

program is both compiled and interpreted. With the compiler, first you translate a

program into an intermediate language called Java byte codes —the platform-

independent codes interpreted by the interpreter on the Java platform. The interpreter

parses and runs each Java byte code instruction on the computer. Compilation

happens just once; interpretation occurs each time the program is executed. The

following figure illustrates how this works.

You can think of Java byte codes as the machine code instructions for the Java

Virtual Machine (Java VM). Every Java interpreter, whether it’s a development tool

or a Web browser that can run applets, is an implementation of the Java VM. Java

byte codes help make “write once, run anywhere” possible. You can compile your

program into byte codes on any platform that has a Java compiler. The byte codes can

then be run on any implementation of the Java VM. That means that as long as a

computer has a Java VM, the same program written in the Java programming

language can run on Windows 2000, a Solaris workstation, or on an iMac.

The Java PlatformA platform is the hardware or software environment in which a program runs. We’ve

already mentioned some of the most popular platforms like Windows 2000, Linux,

Solaris, and MacOS. Most platforms can be described as a combination of the

operating system and hardware. The Java platform differs from most other platforms

in that it’s a software-only platform that runs on top of other hardware-based

platforms.

The Java platform has two components:

The Java Virtual Machine (Java VM)

The Java Application Programming Interface (Java API)

You’ve already been introduced to the Java VM. It’s the base for the Java platform

and is ported onto various hardware-based platforms.

The Java API is a large collection of ready-made software components that provide

many useful capabilities, such as graphical user interface (GUI) widgets. The Java

API is grouped into libraries of related classes and interfaces; these libraries are

known as packages. The next section, What Can Java Technology Do? Highlights

what functionality some of the packages in the Java API provide.

The following figure depicts a program that’s running on the Java platform. As the

figure shows, the Java API and the virtual machine insulate the program from the

hardware.

Native code is code that after you compile it, the compiled code runs on a specific

hardware platform. As a platform-independent environment, the Java platform can be

a bit slower than native code. However, smart compilers, well-tuned interpreters, and

just-in-time byte code compilers can bring performance close to that of native code

without threatening portability.

What Can Java Technology Do?

The most common types of programs written in the Java programming language are

applets and applications. If you’ve surfed the Web, you’re probably already familiar

with applets. An applet is a program that adheres to certain conventions that allow it

to run within a Java-enabled browser.

However, the Java programming language is not just for writing cute, entertaining

applets for the Web. The general-purpose, high-level Java programming language is

also a powerful software platform. Using the generous API, you can write many types

of programs.

An application is a standalone program that runs directly on the Java platform. A

special kind of application known as a server serves and supports clients on a

network. Examples of servers are Web servers, proxy servers, mail servers, and print

servers. Another specialized program is a servlet. A servlet can almost be thought of

as an applet that runs on the server side. Java Servlets are a popular choice for

building interactive web applications, replacing the use of CGI scripts. Servlets are

similar to applets in that they are runtime extensions of applications. Instead of

working in browsers, though, servlets run within Java Web servers, configuring or

tailoring the server.

How does the API support all these kinds of programs? It does so with packages of

software components that provides a wide range of functionality. Every full

implementation of the Java platform gives you the following features:

The essentials: Objects, strings, threads, numbers, input and output, data

structures, system properties, date and time, and so on.

Applets: The set of conventions used by applets.

Networking: URLs, TCP (Transmission Control Protocol), UDP (User Data

gram Protocol) sockets, and IP (Internet Protocol) addresses.

Internationalization: Help for writing programs that can be localized for

users worldwide. Programs can automatically adapt to specific locales and be

displayed in the appropriate language.

Security: Both low level and high level, including electronic signatures,

public and private key management, access control, and certificates.

Software components: Known as JavaBeansTM, can plug into existing

component architectures.

Object serialization: Allows lightweight persistence and communication via

Remote Method Invocation (RMI).

Java Database Connectivity (JDBCTM): Provides uniform access to a wide

range of relational databases.

The Java platform also has APIs for 2D and 3D graphics, accessibility, servers,

collaboration, telephony, speech, animation, and more. The following figure depicts

what is included in the Java 2 SDK.

How Will Java Technology Change My Life?

We can’t promise you fame, fortune, or even a job if you learn the Java programming

language. Still, it is likely to make your programs better and requires less effort than

other languages. We believe that Java technology will help you do the following:

Get started quickly: Although the Java programming language is a powerful

object-oriented language, it’s easy to learn, especially for programmers already

familiar with C or C++.

Write less code: Comparisons of program metrics (class counts, method

counts, and so on) suggest that a program written in the Java programming language

can be four times smaller than the same program in C++.

Write better code: The Java programming language encourages good coding

practices, and its garbage collection helps you avoid memory leaks. Its object

orientation, its JavaBeans component architecture, and its wide-ranging, easily

extendible API let you reuse other people’s tested code and introduce fewer bugs.

Develop programs more quickly: Your development time may be as much as

twice as fast versus writing the same program in C++. Why? You write fewer lines of

code and it is a simpler programming language than C++.

Avoid platform dependencies with 100% Pure Java: You can keep your

program portable by avoiding the use of libraries written in other languages. The

100% Pure JavaTM Product Certification Program has a repository of historical process

manuals, white papers, brochures, and similar materials online.

Write once, run anywhere: Because 100% Pure Java programs are compiled

into machine-independent byte codes, they run consistently on any Java platform.

Distribute software more easily: You can upgrade applets easily from a

central server. Applets take advantage of the feature of allowing new classes to be

loaded “on the fly,” without recompiling the entire program.

ODBC

Microsoft Open Database Connectivity (ODBC) is a standard programming

interface for application developers and database systems providers. Before ODBC

became a de facto standard for Windows programs to interface with database systems,

programmers had to use proprietary languages for each database they wanted to

connect to. Now, ODBC has made the choice of the database system almost irrelevant

from a coding perspective, which is as it should be. Application developers have

much more important things to worry about than the syntax that is needed to port their

program from one database to another when business needs suddenly change.

Through the ODBC Administrator in Control Panel, you can specify the particular

database that is associated with a data source that an ODBC application program is

written to use. Think of an ODBC data source as a door with a name on it. Each door

will lead you to a particular database. For example, the data source named Sales

Figures might be a SQL Server database, whereas the Accounts Payable data source

could refer to an Access database. The physical database referred to by a data source

can reside anywhere on the LAN.

The ODBC system files are not installed on your system by Windows 95. Rather, they

are installed when you setup a separate database application, such as SQL Server

Client or Visual Basic 4.0. When the ODBC icon is installed in Control Panel, it uses

a file called ODBCINST.DLL. It is also possible to administer your ODBC data

sources through a stand-alone program called ODBCADM.EXE. There is a 16-bit and

a 32-bit version of this program and each maintains a separate list of ODBC data

sources.

From a programming perspective, the beauty of ODBC is that the application can be

written to use the same set of function calls to interface with any data source,

regardless of the database vendor. The source code of the application doesn’t change

whether it talks to Oracle or SQL Server. We only mention these two as an example.

There are ODBC drivers available for several dozen popular database systems. Even

Excel spreadsheets and plain text files can be turned into data sources. The operating

system uses the Registry information written by ODBC Administrator to determine

which low-level ODBC drivers are needed to talk to the data source (such as the

interface to Oracle or SQL Server). The loading of the ODBC drivers is transparent to

the ODBC application program. In a client/server environment, the ODBC API even

handles many of the network issues for the application programmer.

The advantages of this scheme are so numerous that you are probably thinking there

must be some catch. The only disadvantage of ODBC is that it isn’t as efficient as

talking directly to the native database interface. ODBC has had many detractors make

the charge that it is too slow. Microsoft has always claimed that the critical factor in

performance is the quality of the driver software that is used. In our humble opinion,

this is true. The availability of good ODBC drivers has improved a great deal recently.

And anyway, the criticism about performance is somewhat analogous to those who

said that compilers would never match the speed of pure assembly language. Maybe

not, but the compiler (or ODBC) gives you the opportunity to write cleaner programs,

which means you finish sooner. Meanwhile, computers get faster every year.

JDBC

In an effort to set an independent database standard API for Java; Sun

Microsystems developed Java Database Connectivity, or JDBC. JDBC offers a

generic SQL database access mechanism that provides a consistent interface to a

variety of RDBMSs. This consistent interface is achieved through the use of “plug-in”

database connectivity modules, or drivers. If a database vendor wishes to have JDBC

support, he or she must provide the driver for each platform that the database and Java

run on.

To gain a wider acceptance of JDBC, Sun based JDBC’s framework on ODBC. As

you discovered earlier in this chapter, ODBC has widespread support on a variety of

platforms. Basing JDBC on ODBC will allow vendors to bring JDBC drivers to

market much faster than developing a completely new connectivity solution.

JDBC was announced in March of 1996. It was released for a 90 day public review

that ended June 8, 1996. Because of user input, the final JDBC v1.0 specification was

released soon after.

The remainder of this section will cover enough information about JDBC for you to

know what it is about and how to use it effectively. This is by no means a complete

overview of JDBC. That would fill an entire book.

JDBC GoalsFew software packages are designed without goals in mind. JDBC is one that,

because of its many goals, drove the development of the API. These goals, in

conjunction with early reviewer feedback, have finalized the JDBC class library into a

solid framework for building database applications in Java.

The goals that were set for JDBC are important. They will give you some insight as to

why certain classes and functionalities behave the way they do. The eight design goals

for JDBC are as follows:

1. SQL Level API

The designers felt that their main goal was to define a SQL interface for Java.

Although not the lowest database interface level possible, it is at a low enough level

for higher-level tools and APIs to be created. Conversely, it is at a high enough level

for application programmers to use it confidently. Attaining this goal allows for future

tool vendors to “generate” JDBC code and to hide many of JDBC’s complexities from

the end user.

2. SQL Conformance

SQL syntax varies as you move from database vendor to database vendor. In

an effort to support a wide variety of vendors, JDBC will allow any query statement

to be passed through it to the underlying database driver. This allows the connectivity

module to handle non-standard functionality in a manner that is suitable for its users.

3. JDBC must be implemental on top of common database interfaces

The JDBC SQL API must “sit” on top of other common SQL level APIs. This goal

allows JDBC to use existing ODBC level drivers by the use of a software interface.

This interface would translate JDBC calls to ODBC and vice versa.

4. Provide a Java interface that is consistent with the rest of the Java system

Because of Java’s acceptance in the user community thus far, the designers feel that

they should not stray from the current design of the core Java system.

5. Keep it simple

This goal probably appears in all software design goal listings. JDBC is no exception.

Sun felt that the design of JDBC should be very simple, allowing for only one method

of completing a task per mechanism. Allowing duplicate functionality only serves to

confuse the users of the API.

6. Use strong, static typing wherever possible

Strong typing allows for more error checking to be done at compile time; also,

less error appear at runtime.

7. Keep the common cases simple

Because more often than not, the usual SQL calls used by the programmer are

simple SELECT’s, INSERT’s, DELETE’s and UPDATE’s, these queries should be

simple to perform with JDBC. However, more complex SQL statements should also

be possible.

Finally we decided to proceed the implementation using Java Networking. And

for dynamically updating the cache table we go for MS Access database.

Java has two things: a programming language and a platform.

Java is a high-level programming language that is all of the

following

Simple Architecture-neutral

Object-oriented Portable

Distributed High-performance

Interpreted multithreaded

Robust Dynamic

Secure

Java is also unusual in that each Java program is both compiled and

interpreted. With a compile you translate a Java program into an intermediate

language called Java byte codes the platform-independent code instruction is

passed and run on the computer.

Compilation happens just once; interpretation occurs each time the program

is executed. The figure illustrates how this works.

You can think of Java byte codes as the machine code instructions for

the Java Virtual Machine (Java VM). Every Java interpreter, whether it’s a

Java development tool or a Web browser that can run Java applets, is an

implementation of the Java VM. The Java VM can also be implemented in

hardware.

Java byte codes help make “write once, run anywhere” possible. You can

compile your Java program into byte codes on my platform that has a Java

compiler. The byte codes can then be run any implementation of the Java

VM. For example, the same Java program can run Windows NT, Solaris, and

Macintosh.

Java Program

Compilers

Interpreter

My Program

Networking

TCP/IP stack

The TCP/IP stack is shorter than the OSI one:

TCP is a connection-oriented protocol; UDP (User Datagram Protocol) is a

connectionless protocol.

IP datagram’s

The IP layer provides a connectionless and unreliable delivery system. It

considers each datagram independently of the others. Any association between

datagram must be supplied by the higher layers. The IP layer supplies a checksum that

includes its own header. The header includes the source and destination addresses.

The IP layer handles routing through an Internet. It is also responsible for breaking up

large datagram into smaller ones for transmission and reassembling them at the other

end.

UDP

UDP is also connectionless and unreliable. What it adds to IP is a checksum

for the contents of the datagram and port numbers. These are used to give a

client/server model - see later.

TCP

TCP supplies logic to give a reliable connection-oriented protocol above IP. It

provides a virtual circuit that two processes can use to communicate.

Internet addresses

In order to use a service, you must be able to find it. The Internet uses an

address scheme for machines so that they can be located. The address is a 32 bit

integer which gives the IP address. This encodes a network ID and more addressing.

The network ID falls into various classes according to the size of the network address.

Network address

Class A uses 8 bits for the network address with 24 bits left over for other

addressing. Class B uses 16 bit network addressing. Class C uses 24 bit network

addressing and class D uses all 32.

Subnet address

Internally, the UNIX network is divided into sub networks. Building 11 is

currently on one sub network and uses 10-bit addressing, allowing 1024 different

hosts.

Host address

8 bits are finally used for host addresses within our subnet. This places a limit

of 256 machines that can be on the subnet.

Total address

The 32 bit address is usually written as 4 integers separated by dots.

Port addresses

A service exists on a host, and is identified by its port. This is a 16 bit number.

To send a message to a server, you send it to the port for that service of the host that it

is running on. This is not location transparency! Certain of these ports are "well

known".

Sockets

A socket is a data structure maintained by the system to handle network

connections. A socket is created using the call socket. It returns an integer that is like

a file descriptor. In fact, under Windows, this handle can be used with Read File and

Write File functions.

#include <sys/types.h>

#include <sys/socket.h>

int socket(int family, int type, int protocol);

Here "family" will be AF_INET for IP communications, protocol will be zero, and

type will depend on whether TCP or UDP is used. Two processes wishing to

communicate over a network create a socket each. These are similar to two ends of a

pipe - but the actual pipe does not yet exist.

JFree Chart

JFreeChart is a free 100% Java chart library that makes it easy for developers

to display professional quality charts in their applications. JFreeChart's extensive

feature set includes:

A consistent and well-documented API, supporting a wide range of chart types;

A flexible design that is easy to extend, and targets both server-side and client-side

applications;

Support for many output types, including Swing components, image files (including

PNG and JPEG), and vector graphics file formats (including PDF, EPS and SVG);

JFreeChart is "open source" or, more specifically, free software. It is distributed under

the terms of the GNU Lesser General Public Licence (LGPL), which permits use in

proprietary applications.

1. Map Visualizations

Charts showing values that relate to geographical areas. Some examples include: (a)

population density in each state of the United States, (b) income per capita for each

country in Europe, (c) life expectancy in each country of the world. The tasks in this

project include:

Sourcing freely redistributable vector outlines for the countries of the world,

states/provinces in particular countries (USA in particular, but also other areas);

Creating an appropriate dataset interface (plus default implementation), a rendered,

and integrating this with the existing XYPlot class in JFreeChart;

Testing, documenting, testing some more, documenting some more.

2. Time Series Chart Interactivity

Implement a new (to JFreeChart) feature for interactive time series charts --- to

display a separate control that shows a small version of ALL the time series data, with

a sliding "view" rectangle that allows you to select the subset of the time series data to

display in the main chart.

3. Dashboards

There is currently a lot of interest in dashboard displays. Create a flexible dashboard

mechanism that supports a subset of JFreeChart chart types (dials, pies, thermometers,

bars, and lines/time series) that can be delivered easily via both Java Web Start and an

applet.

4. Property Editors

The property editor mechanism in JFreeChart only handles a small subset of the

properties that can be set for charts. Extend (or reimplement) this mechanism to

provide greater end-user control over the appearance of the charts.

5. REPORT

SCREEN SHOTS

Fig 5.1 nymble server

Fig 5.2 nymble server authentication

Fig 5.3 nymble home page

Fig 5.4 nymble view

Fig 5.5 user view

Fig 5.6 adding ip address

Fig 5.7 blocking ip address

Fig 5.8 pseudo manager on

Fig 5.5 file access

6. TESTING

TESTING

6.1 BLOCK & WHITE BOX TESTING

Black Box Testing

Black Box Testing is testing the software without any knowledge of the inner

workings, structure or language of the module being tested. Black box tests, as most

other kinds of tests, must be written from a definitive source document, such as

specification or requirements document, such as specification or requirements

document. It is a testing in which the software under test is treated, as a black

box .you cannot “see” into it. The test provides inputs and responds to outputs without

considering how the software works.

White Box Testing

White Box Testing is a testing in which in which the software tester has

knowledge of the inner workings, structure and language of the software, or at least its

purpose. It is purpose. It is used to test areas that cannot be reached from a black box

level.

6.2 UNIT TESTING

Unit testing is usually conducted as part of a combined code and unit test phase of the

software lifecycle, although it is not uncommon for coding and unit testing to be

conducted as two distinct phases.

Test strategy and approach

Field testing will be performed manually and functional tests will be written in

detail.

Test objectives

All field entries must work properly.

Pages must be activated from the identified link.

The entry screen, messages and responses must not be delayed.

Features to be tested

Verify that the entries are of the correct format

No duplicate entries should be allowed

All links should take the user to the correct page.

6.3 SYSTEM TESTING

The purpose of testing is to discover errors. Testing is the process of trying to

discover every conceivable fault or weakness in a work product. It provides a way to

check the functionality of components, sub assemblies, assemblies and/or a finished

product It is the process of exercising software with the intent of ensuring that the

Software system meets its requirements and user expectations and does not fail in an

unacceptable manner. There are various types of test. Each test type addresses a

specific testing requirement.

6.4 INTEGRATION TESTING

Software integration testing is the incremental integration testing of two or

more integrated software components on a single platform to produce failures caused

by interface defects.

The task of the integration test is to check that components or software

applications, e.g. components in a software system or – one step up – software

applications at the company level – interact without error.

Test Results: All the test cases mentioned above passed successfully. No defects

encountered.

6.5 FUNCTIONAL TESTING

Functional tests provide systematic demonstrations that functions tested are

available as specified by the business and technical requirements, system

documentation, and user manuals.

Functional testing is centered on the following items:

Valid Input : identified classes of valid input must be accepted.

Invalid Input : identified classes of invalid input must be rejected.

Functions : identified functions must be exercised.

Output : identified classes of application outputs must be exercised.

Systems/Procedures : interfacing systems or procedures must be invoked.

Organization and preparation of functional tests is focused on requirements, key

functions, or special test cases. In addition, systematic coverage pertaining to identify

Business process flows; data fields, predefined processes, and successive processes

must be considered for testing. Before functional testing is complete, additional tests

are identified and the effective value of current tests is determined.

TEST CASE TABLE

TABLE:

A database is a collection of data about a specific topic.

VIEWS OF TABLE

We can work with a table in two types,

1. Design View

2. Datasheet View

Design View

To build or modify the structure of a table we work in the table design view.

We can specify what kind of data will be hold.

Datasheet View

To add, edit or analyses the data itself we work in tables datasheet view mode.

QUERY

A query is a question that has to be asked the data. Access gathers data that

answers the question from one or more table. The data that make up the answer is

either dynaset (if you edit it) or a snapshot (it cannot be edited).Each time we run

query, we get latest information in the dynaset. Access either displays the dynaset or

snapshot for us to view or perform an action on it, such as deleting or updating.

7. CONCLUSION

CONCLUSION

We have proposed and built a comprehensive credential system called

Nymble, which can be used to add a layer of accountability to any publicly known

anonymizing network.

Servers can blacklist misbehaving users while maintaining their privacy, and we show

how these properties can be attained in a way that is practical, efficient, and sensitive

to the needs of both users and services. We hope that our work will increase the

mainstream

acceptance of anonymizing networks such as Tor, which has, thus far, been

completely blocked by several services because of users who abuse their anonymity.

8. SCOPE FOR FUTURE

DEVELOPMENT

LIMITATIONS & FUTURE ENHANCEMENTS 

IP addresses as the resource for limiting the Sybil attack, our current implementation

closely mimics IP-address blocking employed by Internet services. There are,

however, some inherent limitations to using IP addresses as the scarce resource. If a

user can obtain multiple addresses, she can circumvent both nymble-based and regular

IP-address blocking. Subnetbased blocking alleviates this problem, and while it is

possible to modify our system to support subnet-based blocking, new privacy

challenges emerge; a more thorough description is left for future work.

9. REFERENCES

REFERENCE & BIBLIOGRAPHY

Good Teachers are worth more than thousand books, we have them in Our Department

References Made From:

[1] G. Ateniese, J. Camenisch, M. Joye, and G. Tsudik, “A Practical and Provably

Secure Coalition-Resistant Group Signature, Scheme,” Proc. Ann. Int’l Cryptology

Conf. (CRYPTO), Springer, pp. 255-270, 2000.

[2] G. Ateniese, D.X. Song, and G. Tsudik, “Quasi-Efficient Revocation in Group

Signatures,” Proc. Conf. Financial Cryptography, Springer, pp. 183-197, 2002.

[3] M. Bellare, R. Canetti, and H. Krawczyk, “Keying Hash Functions for Message

Authentication,” Proc. Ann. Int’l Cryptology Conf. (CRYPTO), Springer, pp. 1-15,

1996.

[4] M. Bellare, A. Desai, E. Jokipii, and P. Rogaway, “A Concrete Security Treatment

of Symmetric Encryption,” Proc. Ann. Symp. Foundations in Computer Science

(FOCS), pp. 394-403, 1997.

[5] M. Bellare and P. Rogaway, “Random Oracles Are Practical: A Paradigm for

Designing Efficient Protocols,” Proc. First ACM Conf. Computer and Comm. Security,

pp. 62-73, 1993.

[6] M. Bellare, H. Shi, and C. Zhang, “Foundations of Group Signatures: The Case of

Dynamic Groups,” Proc. Cryptographer’s Track at RSA Conf. (CT-RSA), Springer, pp.

136-153, 2005.

[7] D. Boneh and H. Shacham, “Group Signatures with Verifier-Local Revocation,”

Proc. ACM Conf. Computer and Comm. Security, pp. 168-177, 2004.

[8] S. Brands, “Untraceable Off-Line Cash in Wallets with Observers (Extended

Abstract),” Proc. Ann. Int’l Cryptology Conf. (CRYPTO), Springer, pp. 302-318, 1993.

[9] E. Bresson and J. Stern, “Efficient Revocation in Group Signatures,” Proc. Conf.

Public Key Cryptography, Springer, pp. 190-206, 2001.

[10] J. Camenisch and A. Lysyanskaya, “An Efficient System for Non- Transferable

Anonymous Credentials with Optional Anonymity Revocation,” Proc. Int’l Conf.

Theory and Application of Cryptographic Techniques (EUROCRYPT), Springer, pp.

93-118, 2001.

SITES REFERRED:

http://java.sun.com

http://www.sourcefordgde.com

http://www.networkcomputing.com/

http://www.roseindia.com/

http://www.java2s.com/