a precise termination condition of the probabiistic packet marking algorithm

7/30/2019 A Precise Termination Condition of the Probabiistic Packet Marking Algorithm

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A PRECISE TERMINATION CONDITION OF THE PROBABIISTIC PACKET MARKING ALGORITHM

A PRECISE TERMINATION

CONDITION OF THE PROBABIISTICPACKET MARKING ALGORITHM

IEEE TRANSACTIONS ON DEPENDABLE AND SECURE COMPUTING, VOL. 5, NO. 1, JANUARY-MARCH 2008


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CONTENTS

Chapter 01

Introduction..

Abstract ..

Project Purpose..

Project Scope

Product Features.....

Chapter 02

System Analysis ..

Problem Definition.

Existing System

Proposed System..

Feasibility Study..

Software Requirement ..

Hardware Requirement

Modules Description..

Functional Requirements.

Non Functional Requirements.

Literature Survey



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Chapter 03

System Design

SDLC

Spiral Model

Project Architecture

Data Dictionary ..

ER Models...

ER Diagram ..

OBJECT ORIENTED ANALYSIS AND DESIGN (OOAD)................

UML Diagrams .

Use case.

Class

Sequence.

Activity..

Chapter 04

Process Specification (Pseudo Code / Algorithm)......................

Screen Shots.. .

Chapter 05

Development Phase

Software Requirement Specification..

Coding.



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Chapter 06

Testing

Block & White Box Testing.

Unit Testing

System Testing..

Integration Testing

Test Case Table .

Chapter 07

Conclusion .

Limitations & Future Enhancements

Reference & Bibliography



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Chapter 01

Introduction

THE denial-of-service (DoS) attack has been a pressing problem in recent years.

DoS defense research has blossomed into one of the main streams in network security. Various

techniques such as the pushback message, ICMP traceback, and the packet filtering techniques

are the results from this active field of research. The probabilistic packet marking (PPM)

algorithm by Savage et al. has attracted the most attention in contributing the idea of IP



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traceback. The most interesting point of this IP traceback approach is that it allows routers to

encode certain information on the attack packets based on a predetermined probability. Upon

receiving a sufficient number of marked packets, the victim (or a data collection node) can

construct the set of paths that the attack packets traversed and, hence, the victim can obtain the

location(s) of the attacker(s).

The Probabilistic Packet Marking Algorithm The goal of the PPM algorithm is to obtain

a constructed graph such that the constructed graph is the same as the attack graph, where an

attack graph is the set of paths the attack packets traversed, and a constructed graph is a graph

returned by the PPM algorithm. To fulfill this goal, Savage et al. Suggested a method for

encoding the information of the edges of the attack graph into the attack packets through the

cooperation of the routers in the attack graph and the victim site. Specifically, the PPM algorithm

is made up of two separated procedures: the packet marking procedure, which is executed on the

router side, and the graph reconstruction procedure, which is executed on the victim side.

The packet marking procedure is designed to randomly encode edges information on the

packets arriving at the routers. Then, by using the information, the victim executes the graph

reconstruction procedure to construct the attack graph. We first briefly review the packet marking

procedure so that readers can become familiar with how the router marks information on the

packets

Abstract

The probabilistic packet marking (PPM) algorithm is a promising way to discover the Internet

map or an attack graph that the attack packets traversed during a distributed denial-of-service

attack. However, the PPM algorithm is not perfect, as its termination condition is not well

defined in the literature. More importantly, without a proper termination condition, the attack



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graph constructed by the PPM algorithm would be wrong. In this work, we provide a precise

termination condition for the PPM algorithm and name the new algorithm the Rectified PPM

(RPPM) algorithm. The most significant merit of the RPPM algorithm is that when the algorithm

terminates, the algorithm guarantees that the constructed attack graph is correct, with a specified

level of confidence. We carry out simulations on the RPPM algorithm and show that the RPPM

algorithm can guarantee the correctness of the constructed attack graph under 1) different

probabilities that a router marks the attack packets and 2) different structures of the network

graph. The RPPM algorithm provides an autonomous way for the original PPM algorithm to

determine its termination, and it is a promising means of enhancing the reliability of the PPM

algorithm.

Scope

This project will applicable in secured data sharing in the structured network.

Purpose:

Work we provide a precise termination condition for the PPM algorithm and name the new algorithm therectified PPM (RPPM) algorithm. The most significant merit of the RPPM algorithm is that when thealgorithm terminates, the algorithm guarantees that the constructed attack graph is correct, with aspecified level of confidence.

Features:



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The packet marking procedure aims at encoding every edge of the attack graph, and the routers encodethe information in three marking fields of an attack packet: the start, the end, and the distance fields(wherein Savage et al. [8] has discussed the design of the marking fields). In the following, we describehow a packet stores the information about an edge in the attack graph, and the pseudo code.

When a packet arrives at a router, the router determines how the packet can be processed based on a

random number x (line number 1 in the pseudocode). If x is smaller than the predefined markingprobability pm, the router chooses to start encoding an edge. The router sets the start field of the incomingpacket to the routers address and resets the distance field of that packet to zero. Then, the router forwardsthe packet to the next router. When the packetarrives at the next router, the router again chooses if it should start encoding another edge. For example,for this time, the router chooses not to start encoding a new edge. Then, therouter will discover that the previous router has started marking an edge, because the distance field of thepacket is zero. Eventually, the router sets the end field of the packet to the routers address. Nevertheless,the router increments the distance field of the packet by one so as to indicate the end of the encoding.Now, the start and the end fields together encode an edge of the attack graph.



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Chapter 02

System AnalysisRequirements Analysis is done in order to understand the problem for which the software system is tosolve. For example, the problem could be automating an existing manual process, or developing acompletely new automated system, or a combination of the two. For large systems which have a largenumber of features, and that need to perform many different tasks, understanding the requirements of thesystem is a major task. The emphasis in requirements Analysis is on identifying what is needed from thesystem and not how the system will achieve it goals. This task is complicated by the fact that there areoften at least two parties involved in software development - a client and a developer. The developerusually does not understand the client's problem domain, and the client often does not understand theissues involved in software systems. This causes a communication gap, which has to be adequatelybridged during requirements Analysis.In most software projects, the requirement phase ends with a document describing all the requirements. Inother words, the goal of the requirement specification phase is to produce the software requirementspecification document. The person responsible for the requirement analysis is often called the analyst.There are two major activities in this phase - problem understanding or analysis and requirementspecification in problem analysis; the analyst has to understand the problem and its context. Such analysistypically requires a thorough understanding of the existing system, the parts of which must be automated.Once the problem is analyzed and the essentials understood, the requirements must be specified in therequirement specification document. For requirement specification in the form of document, somespecification language has to be selected (example: English, regular expressions, tables, or a combinationof these). The requirements documents must specify all functional and performance requirements, theformats of inputs, outputs and any required standards, and all design constraints that exits due to political,economic environmental, and security reasons. The phase ends with validation of requirements specifiedin the document. The basic purpose of validation is to make sure that the requirements specified in thedocument, actually reflect the actual requirements or needs, and that all requirements are specified.Validation is often done through requirement review, in which a group of people including representativesof the client, critically review the requirements specification.

Software Requirement or Role of Software Requirement Specification (SRS)IEEE (Institute of Electrical and Electronics Engineering) defines as,

A condition of capability needed by a user to solve a problem or achieve an objective;A condition or capability that must be met or possessed by a system to satisfy a contract, standard,specification, or other formally imposed document.Note that in software requirements we are dealing with the requirements of the proposed system, that is,the capabilities that system, which is yet to be developed, should have. It is because we are dealing withspecifying a system that does not exist in any form that the problem of requirements becomescomplicated. Regardless of how the requirements phase proceeds, the Software RequirementSpecification (SRS) is a document that completely describes what the proposed software should dowithout describing how the system will do it?. The basic goal of the requirement phase is to produce the



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Software Requirement Specification (SRS), which describes the complete external behavior of theproposed software.



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EXISTING SYSTEM

In the existing system PPM algorithm is not perfect, as its termination condition is notwell defined.

Without proper termination condition the attack graph constructed by the PPM algorithmwould be wrong.

The algorithm requires prior knowledge about the network topology.

Proposed System

To propose termination condition of the PPM algorithm, this is missing or is notexplicitly defined in the literature.

Through the new termination condition, the user of the new algorithm is free to determinethe correctness of the constructed graph.

The constructed graph is guaranteed to reach the correctness assigned by the user,independent of the marking probability and the structure of the underlying networkgraph.

In this system we proposed a Probabilistic Packet Marking Algorithm to encode thepacket in the routers to detect the attacked packets.

To reduce the a constructed graph such that the constructed graph is the same as theattack graph, where an attack graph is the set of paths the attack packets traversed,

To construct a graph, is a graph returned by the PPM algorithm.



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SYSTEM CONFIGURATION

Hardware & Software Requirements

Hardware specification:

Monitor : 800*600 minimum resolution of 256 colors

Processor: At least 166 MHz processor

Input : Two or Three button mouse and standard 104 keyboards.

Software specification:

Front End: Java , Swings

Back End: Oracle



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FEASIBLITY 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

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.

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



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esources. 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.

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.

Module Description:

Path Construction

In this module the path will be constructed which the data packets should traverse.

This path should be dynamically changed in case of traffic and failure in router.

Packet marking procedure

In this module, each packet will be marked with random values. These values are

encoded and its appended in the start or in the edge of the packets. These values are checked by

the packet marking procedure.

Router maintenance

In this module the router availability will be checked depends upon the router

availability the path will be constructed.

TPN Generation

In this module the encoded values in the packet are retrieved and its decoded and

checked with the generated code.



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Re-Construction Path

In this module the path will be re-constructed with the received packets its

validated with the constructed path.

In Module Given Input and Expected output

Path Construction

Given Input:

Select the paths for data traverse.

Expected Output:

Path will be generated.

Packet marking procedure

Given Input:

Select the values to be encoded.

Expected Output:

Packet will be encoded and then it will be appended to the

packets.

Router maintenance

Given Input:

Design the graphical user interface for router maintenance.

Expected Output:

Change the router availability dynamically.

TPN Generation

Given Input:

Retrieve the encoded values.

Expected Output:

Get the exact values by decoding the number.

Re-Construction Path

Given Input: Retrieve the path from the attack graph.

Expected Output: Get the reconstructed path.



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Function Requirements

Functional requirements specify which outputs should be produced from the given inputs. 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.

All the operations to be performed on the input data to obtain the output should be specified.

Updating Work status.

Problem resolution.

Error occurrence in the system.

Customer requests.

NON FUNCTIONAL REQUIREMENTS

The project non functional requirements include the following.

3.3.1 USABILITY

The system is used by the four persons namely Administrator, Project Manager,

Developer and the customer. Each person is having their own roles and are separated by the

security issues.

3.3.2 RELIABLITY

The system is said to be reliable because the entire system was built using java which is

most robust language. Reliability refers to the standards of the system.

3.3.3 PERFORMANCE



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System is highly functional and good in performance. The system must use the minimal

set of variables and minimal usage of the control structures will dynamically increase the

performance of the system.

3.3.4 SUPPORTABILITY

The system is supportable with different platforms and a wide range of machines. the java

code used in this project is more flexible and having a feature of platform independence. And

also added support for wide range of mobile phone which supports CLDC platform.

3.3.5 IMPLEMENTATION

The system would be implemented in a networked and mobile based WAP environment.

3.3.6 INTERFACE

This system uses three user interfaces. Most of the project is developed by using the java

Swing user interface and some components in mobile interface and customer module in the web

based interface.

3.3.7 PACKAGING

The entire system was packaged into single package.

3.3.8 LEGAL

The legal issues of this project are unknown as that rights are not applicable for the

project done for the academics. All the legal rights are sol proprietor of the organization.

Literature Survey



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Chapter 03

System Design:

The purpose of the design phase is to plan a solution of the problem specified by the

requirement document. This phase is the first step in moving from problem domain to the

solution domain. The design of a system is perhaps the most critical factor affecting the

quality of the software, and has a major impact on the later phases, particularly testing and

maintenance. The output of this phase is the design document. This document is similar to a

blue print or plan for the solution, and is used later during implementation, testing and

maintenance.

The design activity is often divided into two separate phase-system design and detailed

design. System design, which is sometimes also called top-level design, aims to identify the

modules that should be in the system, the specifications of these modules, and how they

interact with each other to produce the desired results. At the end of system design all the

major data structures, file formats, output formats, as well as the major modules in the system

and their specifications are decided.

During detailed design the internal logic of each of the modules specified in system design is

decided. During this phase further details of the data structures and algorithmic design of

each of the modules is specified. The logic of a module is usually specified in a high-level

design description language, which is independent of the target language in which the

software will eventually be implemented. In system design the focus is on identifying the

modules, whereas during detailed design the focus is on designing the logic for each of the



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modules. In other words, in system design the attention is on what components are needed,

while in detailed design how the components can be implemented in software is the issue.

During the design phase, often two separate documents are produced. One for the system

design and one for the detailed design . Together, these documents completely specify the

design of the system. That is they specify the different modules in the system and internal

logic of each of the modules.

A design methodology is a systematic approach to creating a design by application of set of

techniques and guidelines. Most methodologies focus on system design. The two basic

principles used in any design methodology are problem partitioning and abstraction. A large

system cannot be handled as a whole, and so for design it is partitioned into smaller systems.

Abstraction is a concept related to problem partitioning. When partitioning is used during

design, the design activity focuses on one part of the system at a time. Since the part being

designed interacts with other parts of the system, a clear understanding of the interaction is

essential for properly designing the part. For this, abstraction is used. An abstraction of a

system or a part defines the overall behavior of the system at an abstract level without giving

the internal details.

While working with the part of a system, a designer needs to understand only the abstractions

of the other parts with which the part being designed interacts. The use of abstraction allows

the designer to practice the "divide and conquer" technique effectively by focusing one part

at a time, without worrying about the details of other parts.

Like every other phase, the design phase ends with verification of the design. If the design is

not specified in some executable language, the verification has to be done by evaluating the

design documents. One way of doing this is thorough reviews. Typically, at least two design



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reviews are held-one for the system design and one for the detailed and one for the detailed

design.

Software Development Life Cycle

This document play a vital role in the development of life cycle (SDLC) as it describes the

complete requirement of the system. It means for use by developers and will be the basic

during testing phase. Any changes made to the requirements in the future will have to go

through formal change approval process.

The trends of increasing technical complexity of the systems, coupled with the need for

repeatable and predictable process methodologies, have driven System Developers to

establish system development models or software development life cycle models.

Nearly three decades ago the operations in an organization used to be limited and so it was

possible to maintain them using manual procedures. But with the growing operations of

organizations, the need to automate the various activities increased, since for manual

procedures it was becoming very difficult, slow and complicated. Like maintaining records

for a thousand plus employees company on papers is definitely a cumbersome job. So, at that

time more and more companies started going for automation.

Since there were a lot of organizations, which were opting for automation, it was felt that

some standard and structural procedure or methodology be introduced in the industry so that

the transition from manual to automated system became easy. The concept of system life

cycle came into existence then. Life cycle model emphasized on the need to follow some

structured approach towards building new or improved system. There were many models

suggested. A waterfall model was among the very first models that came into existence. Later



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on many other models like prototype, rapid application development model, etc were also

introduced.

System development begins with the recognition of user needs. Then there is a preliminary

investigation stage. It includes evaluation of present system, information gathering,

feasibility study, and request approval. Feasibility study includes technical, economic, legal

and operational feasibility. In economic feasibility cost-benefit analysis is done. After that,

there are detailed design, implementation, testing and maintenance stages.

In this session, we'll be learning about various stages that make system's life cycle. In

addition, different life cycles models will be discussed. These include Waterfall model,

Prototype model, Object-Oriented Model, spiral model and Dynamic Systems Development

Method (DSDM).

SPIRAL MODEL

SPIRAL MODEL was defined by Barry Boehm in his 1988 article, A spiral Model of

Software Development and Enhancement. This model was not the first model to discuss

iterative development, but it was the first model to explain why the iteration models.

As originally envisioned, the iterations were typically 6 months to 2 years long. Each phase

starts with a design goal and ends with a client reviewing the progress thus far. Analysis and

engineering efforts are applied at each phase of the project, with an eye toward the end goal

of the project.

The steps for Spiral Model can be generalized as follows:

The new system requirements are defined in as much details as possible. This usually

involves interviewing a number of users representing all the external or internal users

and other aspects of the existing system.



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A preliminary design is created for the new system.

A first prototype of the new system is constructed from the preliminary design. This

is usually a scaled-down system, and represents an approximation of the

characteristics of the final product.

A second prototype is evolved by a fourfold procedure:

Evaluating the first prototype in terms of its strengths, weakness, and risks.

Defining the requirements of the second prototype.

Planning an designing the second prototype.

Constructing and testing the second prototype.

At the customer option, the entire project can be aborted if the risk is deemed too

great. Risk factors might involve development cost overruns, operating-cost

miscalculation, or any other factor that could, in the customers judgment, result in a

less-than-satisfactory final product.

The existing prototype is evaluated in the same manner as was the previous prototype,

and if necessary, another prototype is developed from it according to the fourfold

procedure outlined above.

The preceding steps are iterated until the customer is satisfied that the refined

prototype represents the final product desired.

The final system is constructed, based on the refined prototype.

The final system is thoroughly evaluated and tested. Routine maintenance is carried

on a continuing basis to prevent large scale failures and to minimize down time.

The following diagram shows how a spiral model acts like:



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Fig 1.0-Spiral Model

ADVANTAGES:

Estimates(i.e. budget, schedule etc .) become more relistic as work progresses,



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because important issues discoved earlier.

It is more able to cope with the changes that are software development generally

entails.

You are now ready to edit, run, and compile the project with DJava..

Spiral Model Description

The development spiral consists of four quadrants as shown in the figure above

Quadrant 1: Determine objectives, alternatives, and constraints.

Quadrant 2: Evaluate alternatives, identify, resolve risks.

Quadrant 3: Develop, verify, next-level product.

Quadrant 4: Plan next phases.

Although the spiral, as depicted, is oriented toward software development, the concept is

equally applicable to systems, hardware, and training, for example. To better understand the

scope of each spiral development quadrant, lets briefly address each one.

Quadrant 1: Determine Objectives, Alternatives, and Constraints

Activities performed in this quadrant include:

Establish an understanding of the system or product objectivesnamely performance,

functionality, and ability to accommodate change.

Investigate implementation alternativesnamely design, reuse, procure, and procure/

modify. Investigate constraints imposed on the alternativesnamely technology, cost,

schedule, support, and risk. Once the system or products objectives, alternatives, and

constraints are understood, Quadrant 2 (Evaluate alternatives, identify, and resolve risks) is

performed.



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Quadrant 2: Evaluate Alternatives, Identify, Resolve Risks

Engineering activities performed in this quadrant select an alternative approach that best

satisfies technical, technology, cost, schedule, support, and risk constraints. The focus here is

on risk mitigation. Each alternative is investigated and prototyped to reduce the risk

associated with the development decisions. Boehm describes these activities as follows:

This may involve prototyping, simulation, benchmarking, reference checking, administering

user

questionnaires, analytic modeling, or combinations of these and other risk resolution

techniques.

The outcome of the evaluation determines the next course of action. If critical operationaland/or technical issues (COIs/CTIs) such as performance and interoperability (i.e., external

and internal) risks remain, more detailed prototyping may need to be added before

progressing to the next quadrant. Dr. Boehm notes that if the alternative chosen is

operationally useful and robust enough to serve as a low-risk base for future product

evolution, the subsequent risk-driven steps would be the evolving series of evolutionary

prototypes going toward the right (hand side of the graphic) the option of writing

specifications would be addressed but not exercised. This brings us to Quadrant 3.

Quadrant 3: Develop, Verify, Next-Level Product

If a determination is made that the previous prototyping efforts have resolved the COIs/CTIs,

activities to develop, verify, next-level product are performed. As a result, the basic

waterfall approach may be employedmeaning concept of operations, design,

development, integration, and test of the next system or product iteration. If appropriate,

incremental development approaches may also be applicable.

Quadrant 4: Plan Next Phases

The spiral development model has one characteristic that is common to all modelsthe need

for advanced technical planning and multidisciplinary reviews at critical staging or control



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points. Each cycle of the model culminates with a technical review that assesses the status,

progress, maturity, merits, risk, of development efforts to date; resolves critical operational

and/or technical issues (COIs/CTIs); and reviews plans and identifies COIs/CTIs to be

resolved for the next iteration of the spiral.

Subsequent implementations of the spiral may involve lower level spirals that follow the

same quadrant paths and decision considerations.

UML Diagrams :

Object Oriented Analysis:

An object-oriented system is composed of objects. The behavior of the system is achieved

through collaboration between these objects, and the state of the system is the combined state of

all the objects in it. Collaboration between objects involves them sending messages to each other.

The exact semantics of message sending between objects varies depending on what kind of

system is being modeled. In some systems, "sending a message" is the same as "invoking a

method".

Object Oriented Analysis aims to model the problem domain, the problem we want to solve by

developing an object-oriented (OO)System The source of the analysis is a written requirement

statements, and/or written use cases, UML diagrams can be used to illustrate the statements

An analysis model will not take into account implementation constraints, such as concurrency,

distribution, persistence, or inheritance, nor how the system will be built The model of a system

can be divided into multiple domains each of which are separately analyzed, and represent



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separate business, technological, or conceptual areas of interest The result of object-oriented

analysis is a description of what is to be built, using concepts and relationships between

concepts, often expressed as a conceptual model. Any other documentation that is needed to

describe what is to be built, is also included in the result of the analysis. That can include a

detailed user interface mock-up document The implementation constraints are decided during the

object-oriented design (OOD) process

Object Oriented Design

Object-Oriented Design (OOD) is an activity where the designers are looking for logical

solutions to solve a problem, using Objects Object-oriented design takes the conceptual model

that is the result of object-oriented analysis, and adds implementation constraints imposed by the

environment, the programming language and the chosen tools, as well as architectural

assumptions chosen as basis of Design

The concepts in the conceptual model are mapped to concrete classes, to abstract interfaces in

APIs and to roles that the objects take in various situations. The interfaces and their

implementations for stable concepts can be made available as reusable services. Concepts

identified as unstable in object-oriented analysis will form basis for policy classes that make

decisions, implement environment-specific or situation specific logic or algorithms

The result of the object-oriented design is a detail description how the system can be built, using

objects .Object-oriented software engineering (OOSE) is an object modeling language and

Methodology



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OOSE was developed by Ivar Jacobson in 1992 while at Objectory AB. It is the first object-

oriented design methodology to employ use cases to drive software design. It also uses other

design products similar to those used by OMT

The tool Objectory was created by the team at Objectory AB to implement the OOSE

methodology. After success in the marketplace, other tool vendors also supported OOSE After

Rational bought Objectory AB, the OOSE notation, methodology, and tools became superseded

As one of the primary sources of the Unified Modeling Language (UML), concepts and

notation from OOSE have been incorporated into UML

The methodology part of OOSE has since evolved into the Rational Unified Process

(RUP)

The OOSE tools have been replaced by tools supporting UML and RUP

OOSE has been largely replaced by the UML notation and by the RUP methodology

Unified Modeling Language

The heart of object-oriented problem solving is the construction of a model. The model abstractsthe essential details of the underlying problem from its usually complicated real world. Severalmodeling tools are wrapped under the heading of the UML, which stands for UnifiedModeling Language. The purpose of this course is to present important highlights of the UML.

At the center of the UML are its nine kinds of modeling diagrams, which we describe here. Use case diagrams

Class diagrams

Object diagrams

Sequence diagrams

Collaboration diagrams

Statechart diagrams

Activity diagrams

http://bdn.borland.com/article/#use-case-diagramhttp://bdn.borland.com/article/#classdiagramshttp://bdn.borland.com/article/#object-diagramshttp://bdn.borland.com/article/#sequence-diagramshttp://bdn.borland.com/article/#collaboration-diagramshttp://bdn.borland.com/article/#statechart-diagramshttp://bdn.borland.com/article/#activity-diagramshttp://bdn.borland.com/article/#use-case-diagramhttp://bdn.borland.com/article/#classdiagramshttp://bdn.borland.com/article/#object-diagramshttp://bdn.borland.com/article/#sequence-diagramshttp://bdn.borland.com/article/#collaboration-diagramshttp://bdn.borland.com/article/#statechart-diagramshttp://bdn.borland.com/article/#activity-diagrams


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Component diagrams

Deployment diagrams

Some of the sections of this course contain links to pages with more detailed information. Andevery section has short questions. Use them to test your understanding of the section topic.

Why is UML important?Let's look at this question from the point of view of the construction trade. Architects designbuildings. Builders use the designs to create buildings. The more complicated the building, themore critical the communication between architect and builder. Blueprints are the standardgraphical language that both architects and builders must learn as part of their trade.Writing software is not unlike constructing a building. The more complicated the underlyingsystem, the more critical the communication among everyone involved in creating and deployingthe software. In the past decade, the UML has emerged as the software blueprint language foranalysts, designers, and programmers alike. It is now part of the software trade. The UML giveseveryone from business analyst to designer to programmer a common vocabulary to talk aboutsoftware design.

The UML is applicable to object-oriented problem solving. Anyone interested in learning UMLmust be familiar with the underlying tenet of object-oriented problem solving -- it all begins withthe construction of a model. A model is an abstraction of the underlying problem. The domain isthe actual world from which the problem comes.Models consist ofobjects that interact by sending each other messages. Think of an object as"alive." Objects have things they know (attributes) and things they can do (behaviors oroperations). The values of an object's attributes determine its state.Classes are the "blueprints" for objects. A class wraps attributes (data) and behaviors (methodsor functions) into a single distinct entity. Objects are instances of classes.

.Group Term Definition

Business Accounting Periods A defined period of time wherebyperformance reports may be extracted.(normally 4 week periods).

Technical Association A relationship between two or more entities.Implies a connection of some type - forexample one entity uses the services ofanother, or one entity is connected to anotherover a network link.

Technical Class A logical entity encapsulating data andbehavior. A class is a template for an object -the class is the design, the object the runtimeinstance.

Technical Component Model The component model provides a detailedview of the various hardware and softwarecomponents that make up the proposedsystem. It shows both where thesecomponents reside and how they inter-relatewith other components. Component

http://bdn.borland.com/article/#component-and-deployment-diagranshttp://bdn.borland.com/article/#component-and-deployment-diagranshttp://bdn.borland.com/article/#component-and-deployment-diagranshttp://bdn.borland.com/article/#component-and-deployment-diagrans


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Business Customer A person or a company that requests Anentity to transport goods on their behalf.

Technical Deployment Architecture A view of the proposed hardware that willmake up the new system, together with thephysical components that will execute onthat hardware. Includes specifications formachine, operating system, network links,backup units &etc.

Technical Deployment Model A model of the system as it will be physicallydeployed

Technical Extends Relationship A relationship between two use cases inwhich one use case 'extends' the behavior ofanother. Typically this represents optional

behavior in a use case scenario - for examplea user may optionally request a list or reportat some point in a performing a business usecase.

Technical Includes Relationship A relationship between two use cases inwhich one use case 'includes' the behavior.This is indicated where there a specificbusiness use cases which are used from manyother places - for example updating a trainrecord may be part of many larger businessprocesses.

Technical Use Case A Use Case represents a discrete unit of interaction between a user (human ormachine) and the system. A Use Case is asingle unit of meaningful work; for examplecreating a train, modifying a train andcreating orders are all Use Cases.Each UseCase has a description which describes thefunctionality that will be built in theproposed system. A Use Case may 'include'another Use Case's functionality or 'extend'another Use Case with its own behavior.UseCases are typically related to 'actors'. Anactor is a human or machine entity thatinteracts with the system to performmeaningful work.

1.1 Actors



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Actors are the users of the system being modeled. Each Actor will have a well-definedrole, and in the context of that role have useful interactions with the system.

A person may perform the role of more than one Actor, although they will only assume

one role during one use case interaction.

An Actor role may be performed by a non-human system, such as another computerprogram.

uc Actors

istered Trial Vers

istered Trial Vers

istered Trial VersSecuritySpecialist

Figure 2: Actors

Use Cases

Use case Diagrams represent the functionality of the system from a users point of view.

Use cases are used during requirements elicitation and analysis to represent the functionality of

the system. Use cases focus on the behavior of the system from external point of view.

Actors are external entities that interact with the system. Examples of actors include users

like administrator, bank customer etc., or another system like central database.

Use Case Model

Sequence Diagram



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Class and object diagrams are static model views. Interaction diagrams are dynamic. They

describe how objects collaborate.

A sequence diagram is an interaction diagram that details how operations are carried out -- whatmessages are sent and when. Sequence diagrams are organized according to time. The time

progresses as you go down the page. The objects involved in the operation are listed from left toright according to when they take part in the message sequence.Class Diagram

A Class diagram gives an overview of a system by showing its classes and the relationshipsamong them. Class diagrams are static -- they display what interacts but not what happens whenthey do interact.

Our class diagram has three kinds of relationships. association -- a relationship between instances of the two classes. There is an association

between two classes if an instance of one class must know about the other in order toperform its work. In a diagram, an association is a link connecting two classes.

aggregation -- an association in which one class belongs to a collection. An aggregation

has a diamond end pointing to the part containing the whole. generalization -- an inheritance link indicating one class is a superclass of the other. A

generalization has a triangle pointing to the superclass.

Activity Diagram

An activity diagram is essentially a fancy flowchart. Activity diagrams and statechart diagramsare related. While a statechart diagram focuses attention on an object undergoing a process (or on



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a process as an object), an activity diagram focuses on the flow of activities involved in a singleprocess. The activity diagram shows the how those activities depend on one another.



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Class Diagram

PPM Source

pm

sendData()

constructedGraph()

PPM Routerappend

marking()

PPM Destination

decodeorginaldata

Re-Consrtuction Path()

TPN()



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Use Case Diagram

Marking ProbabilityRouter

Transition Router

Attack Graph

Leaf Router

Source File

Constructed PathSource

TPN

Destination



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Collaboration Diagram

PPM

SourceRouter Destination

1: packetMarking 2: Destination

Sequence Diagram

PPM Source Router Destination

packetMarking

Destination



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Activity Diagram

PPM Source

Marking Condition

Start Field

True

End Field

False

Router

Management

PPM

Destination



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Development Phase

Once the design is complete, most of the major decisions about the system have been made. The

goal of the coding phase is to translate the design of the system into code in a given

programming language. For a given design, the aim of this phase is to implement the design in

the best possible manner. The coding phase affects both testing and maintenance profoundly. A

well written code reduces the testing and maintenance effort. Since the testing and maintenance

cost of software are much higher than the coding cost, the goal of coding should be to reduce thetesting and maintenance effort. Hence, during coding the focus should be on developing

programs that are easy to write. Simplicity and clarity should be strived for, during the coding

phase.

An important concept that helps the understandability of programs is structured programming.

The goal of structured programming is to arrange the control flow in the program. That is,

program text should be organized as a sequence of statements, and during execution, the

statements are executed in the sequence in the program.

For structured programming, a few single-entry-single-exit constructs should be used. These

constructs includes selection (if-then-else), and iteration (while - do, repeat - until etc). With

these constructs it is possible to construct a program as sequence of single - entry - single - exit

constructs. There are many methods available for verifying the code. Some methods are static in

nature that is, that is they do not involve execution of the code. Examples of such methods are

data flow analysis, code reading, code reviews, testing (a method that involves executing the

code, which is used very heavily). In the coding phase, the entire system is not tested together.

Rather, the different modules are tested separately. This testing of modules is called "unit

testing". Consequently, this phase is often referred to as "coding and unit testing". The output of

this phase is the verified and unit tested code of the different modules.



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Java Technology

Java technology is both a programming language and a platform.

The Java Programming Language

The 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



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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 its 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.



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The Java Platform

A platform is the hardware or software environment in which a

program runs. Weve 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 its a software-only

platform that runs on top of other hardware-based platforms.

The Java platform has two components:

TheJava Virtual Machine (Java VM) TheJava Application Programming Interface (Java API)

Youve already been introduced to the Java VM. Its 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 thats running on the Java

platform. As the figure shows, the Java API and the virtual machine insulate

the program from the hardware.



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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 youve surfed the Web, youre

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 appletsin that they are runtime extensions of applications. Instead of working in

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

tailoring the server.



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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

followingfeatures:

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.



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How Will Java Technology Change My Life?

We cant 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, its 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

peoples tested code and introduce fewer bugs.



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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.

Finally we decided to proceed the implementation using Java Networking.And for dynamically updating the cache table we go for MS Accessdatabase.

JAVA HA TWO THINGS: A PROGRAMMING

LANGUAGE AND A PLATFORM.

JAVA IS A HIGH-LEVEL PROGRAMMING

LANGUAGE THAT IS ALL OF THE FOLLOWING

SIMPLE ARCHITECTURE-

NEUTRAL



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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.



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YOU CAN THINK OF JAVA BYTE CODES AS THE MACHINE

CODE INSTRUCTIONS FOR THE JAVA VIRTUAL MACHINE (JAVA

VM). EVERY JAVA INTERPRETER, WHETHER ITS 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.


JavaProgram

Compilers

Interpreter

My Program


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Introduction to SwingThis introduction to using Swing in Java will walk you through the basics of Swing. This covers

topics of how to create a window, add controls, postion the controls, and handle events from thecontrols.

The Main Window

Almost all GUI applications have a main or top-level window. In Swing, such window is usually

instance of JFrame or JWindow. The difference between those two classes is in simplicity

JWindow is much simpler than JFrame (most noticeable are visual differences - JWindow does

not have a title bar, and does not put a button in the operating system task bar). So, your

applications will almost always start with a JFrame.

Though you can instantiate a JFrame and add components to it, a good practice is to encapsulate

and group the code for a single visual frame in a separate class. Usually, I subclass the JFrame

and initialize all visual elements of that frame in the constructor.

Always pass a title to the parent class constructor that String will be displayed in the title bar

and on the task bar. Also, remember to always initialize frame size (by calling

setSize(width,height)), or your frame will not be noticeable on the screen.

package com.neuri.handsonswing.ch1;

import javax.swing.JFrame;

public class MainFrame extends JFrame

{

public MainFrame()



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{

super("My title");

setSize(300, 300);

}

}

Now you have created your first frame, and it is time to display it. Main frame is usually

displayed from the main method but resist the urge to put the main method in the frame class.

Always try to separate the code that deals with visual presentation from the code that deals with

application logic starting and initializing the application is part of application logic, not a part

of visual presentation. A good practice is to create an Application class that will contain

initialization code.


public class Application

{

public static void main(String[] args)

{

// perform any initialization

MainFrame mf = new MainFrame();

mf.show();

}

}

If you run the code now, you will see an empty frame. When you close it, something not quite

obvious will happen (or better said, will not happen). The application will not end. Remember

that the Frame is just a visual part of

application, not application logic if you do

not request application termination when

the window closes, your program will still

run in the background (look for it in the process

list). To avoid this problem, add the following

line to the MainFrame constructor:



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setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

Before Java2 1.3, you had to register a window listener and then act on the window closing event

by stopping the application. Since Java2 1.3, you can specify a simple action that will happen

when a window is closed with this shortcut. Other options are HIDE_ON_CLOSE (the default

window is closed but application still runs) and DO_NOTHING_ON_CLOSE (rather strange

option that ignores a click on the X button in the upper right corner).

Adding Components

Now is the time to add some components to the window. In Swing (and the Swing predecessor,

AWT) all visual objects are subclasses of Component class. The Composite pattern was applied

here to group visual objects into Containers, special components that can contain other

components. Containers can specify the order, size and position of embedded components (and

this can all be automatically calculated, which is one of the best features of Swing).

JButton is a component class that represents a general purpose button it can have a text caption

or an icon, and can be pressed to invoke an action. Lets add the button to the frame (note: add

imports for javax.swing.* and java.awt.* to the MainFrame source code so that you can use all

the components).

When you work with JFrame, you want to put objects into its content pane special container

intended to hold the window contents. Obtain the reference to that container with the

getContentPane() method.

Container content = getContentPane();

content.add(new JButton("Button 1"));



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If you try to add more buttons to the frame, most likely only the last one added will be displayed.

That is because the default behavior of JFrame content pane is to display a single component,

resized to cover the entire area.

Grouping Components

To put more than one component into a place intended for a single component, group them into a

container. JPanel is a general purpose container, that is perfect for grouping a set of components

into a larger component. So, lets put the buttons into a JPanel:

JPanel panel=new JPanel();

panel.add(new JButton("Button 1"));



content.add(panel);

Layout Management Basics

One of the best features of Swing is automatic component positioning and resizing. That is

implemented trough a mechanism known as Layout management. Special objects layout

managers are responsible for sizing, aligning and positioning components. Each container can



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have a layout manager, and the type of layout manager determines the layout of components in

that container. There are several types of layout managers, but the two you will most frequently

use are FlowLayout (orders components one after another, without resizing) and BorderLayout

(has a central part and four edge areas component in the central part is resized to take as much

space as possible, and components in edge areas are not resized). In the previous examples, you

have used both of them. FlowLayout is the default for a JPanel (that is why all three buttons are

displayed without resizing), and BorderLayout is default for JFrame content panes (that is why a

single component is shown covering the entire area).

Layout for a container is defined using the setLayout method (or usually in the constructor). So,

you could change the layout of content pane to FlowLayout and add several components, to see

them all on the screen.

The best choice for the window content pane is usually a BorderLayout with a central content

part and a bottom status (or button) part. The top part can contain a toolbar, optionally.

Now, lets combine several components and

layouts, and introduce a new component

JTextArea. JTextArea is basically a multiline

editor. Initialize the frame content pane

explicitly to BorderLayout, put a new

JTextArea into the central part and move the

button panel below.


import java.awt.*;

import javax.swing.*;

public class MainFrame extends JFrame

{

public MainFrame()

{

super("My title");

setSize(300,300);



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setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

Container content = getContentPane();

content.setLayout(new BorderLayout());

JPanel panel = new JPanel(new FlowLayout());




content.add(panel, BorderLayout.SOUTH);

content.add(new JTextArea(), BorderLayout.CENTER);

}

}

Notice that the layouts for content pane and the button panel are explicitly defined. Also notice

the last two lines of code this is the other version of add method, which allows you to specify

the way the component is added. In this case, we specify the area of BorderLayout layout

manager. Central part is called BorderLayout.CENTER, and other areas are called

BorderLayout.NORTH (top), BorderLayout.SOUTH (bottom), BorderLayout.WEST (left) and

BorderLayout.EAST (right). If you get confused about this, just remember land-maps from your

geography classes.

OVERVIEW OF JAVA RMI

DISTRIBUTED COMPUTING

In the present modern Internet World, Distributed Computing is one of the key areasthat play an important role. Distributed systems require that computations running in differentaddress spaces, potentially on different hosts, be able to communicate with each other. .

An alternative to sockets used in java is Remote Procedure Call (RPC), which abstractsthe communication interface to the level of a procedure call. Instead of working directly withsockets, the programmer has the illusion of calling a local procedure, when in fact the argumentsof the call are packaged up and shipped off to the remote target of the call. RPC systems encodearguments and return values using an external data representation, such as XDR. In order tomatch the semantics of object invocation, distributed object systems require remote methodinvocation or RMI. .

RMI provides the mechanism by which the server and the client communicate and passinformation back and forth. Distributed object systems finds its applications to locate remoteobjects, Communicate with remote objects and Load class byte codes for objects that are passed



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as parameters or return values. In such systems, a local surrogate (stub) object manages theinvocation on a remote object.

The Java programming language's RMI system assumes the homogeneous environmentof the Java virtual machine (JVM), and the system can therefore take advantage of the Javaplatform's object model whenever possible.

REMOTE METHOD INVOCATIONRMI provides the mechanism by which the server and the client communicate andpass information back and forth. Server creates a number of remote objects, makes references tothose remote objects. The client gets a remote reference to one or more remote objects in theserver and then invokes methods on them.

Java provides a program called RMI Registry which executes on the servermachine. The Registry maps names to object references and listens for client request on adesignated port. The client looks up the remote object by its name in the servers registry andthen invokes the method of server object.

THE RSA ALGORITHM

INTRODUCTION:The RSA scheme is a block cipher in which the plaintext and cipher text are

integers between 0 and n-1 for some n.A typical size for n is 1024 bits or 309 decimal digits. TheRSA scheme has since that time reigned supreme as the most widely accepted and implementedgeneral purpose to public key encryption.

DESCRIPTION:The scheme developed by Rivest, Shamir and Adleman makes use of an

expression with exponentials. Plaintext is encrypted in blocks, with each block having a binaryvalue less than some number n.That is, the block size must be less than or equal to log2(n) ; inpractice, the block size is k bits, where 2k< n < 2k+1 .Encryption and decryption are of thefollowing form, for some plaintext block M and cipher text block C:

C = Me mod nM = Cd mod n = (Me) d mod n = Med mod n

Both sender and receiver must know the value of n.The sender knows the value of e and only thereceiver knows the value of d.Thus, this is a public key encryption algorithm with a public key ofKU = {d,n}.

For this algorithm to be satisfactory for public key encryption, the following requirements to bemet :1. It is possible to find the values of e, d, n such that Med = M mod n for all M < n.2. It is relatively easy to calculate Me and Cd for all values of M < n.3. It is infeasible to determine d given e and n.

For now,we focus on the first requirement and consider the other questions later.Weneed to find a relationship of the form

Med = M mod n



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Given two prime numbers and q, and two integers and m, such that n=pq and0


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4. Select e such that e is relatively prime to (n) and less than (n)5. Determine d such that de = 1 mod (n)

KEY GENERATION

Before the application of the public key cryptosystem, each participant must generate a pair ofkeys. This involves the following tasks:1. Determining two prime numbers, p and q2. Selecting either e or d and calculating the other

The procedure for picking a prime number is as follows:1. Pick an odd integer n at random2. Pick an integer a < n at random3. Perform the probabilistic primarily test, such as Miller Rabin. If n fails the test, reject thevalue n and go to step 1.4. If n has passed a sufficient number of tests, accept n; otherwise, go to step

THE SECURITY OF RSAThree possible approaches to attacking the RSA algorithm are as follows :1. Brute force: This involves trying all possible private keys.2. Mathematical attacks: There are several approaches, all equivalent in effect to factoring theproduct of two primes3. Timing attacks: These depend on the running time of the decryption algorithm.

SCREEN SHOTS



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Sample Code:

import javax.swing.*;import java.awt.*;import java.io.*;

import java.net.*;import java.rmi.server.*;

import java.rmi.*;

/***

* @author Admin*/

public class Source extends JFrame {

/** Creates new form Source */

int i=0;char c;

String str="";String s[];

String ss[]=new String[1];// ServerSocket serversocket;

Socket socket;JLabel l1,l2,l3;

JTextField t1,t2,t3;// String s[];

public Source() {initComponents();

//Container con=getContentPane();

setLocation(350,300);setSize(650,500);

setTitle("Packet Marking Source");

}

/** This method is called from within the constructor to* initialize the form.

* WARNING: Do NOT modify this code. The content of this method is* always regenerated by the Form Editor.

*/



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/* public void serverStart(){

try

{//serversocket=new ServerSocket(9001);//while(true)

//{

// }}

catch(Exception e){

e.printStackTrace();}

}*/

// //GEN-BEGIN:initComponentsprivate void initComponents() {

jLabel1 = new JLabel(" Packet Marking Source");jTextField1 = new javax.swing.JTextField();

jButton1 = new javax.swing.JButton("Browse");jTabbedPane1 = new javax.swing.JTabbedPane();

jPanel1 = new JPanel();jTabbedPane1.addTab("Client - Machine",jPanel1) ;

jLabel2 = new JLabel("Source ID");jLabel3 = new JLabel("Destination ID");

jTextField2 = new JTextField();jTextField3 = new JTextField();

jScrollPane1 = new JScrollPane();jTextArea1 = new JTextArea();

jButton2 = new JButton("Send");jButton3 = new JButton("Exit");

jPanel2 = new JPanel();jTabbedPane1.addTab("Leaf - Router",jPanel2);

jScrollPane2 =new JScrollPane();jTextArea2 = new JTextArea();

jLabel4 = new JLabel("Marking - Probability");jLabel5 = new JLabel("Leaf - Router");

jTextField4 = new JTextField();jLabel6 = new JLabel("Predefined Value");

jTextField5 = new JTextField();jButton4 = new JButton("Packet-Marking");

jButton5 = new JButton("Close");


7/30/2019 A Precise Termination Condition of the Probabiistic P

a precise termination condition of the probabiistic packet marking algorithm

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