Protecting location privacy in sensor networks against a global eavesdropper

PROTECTING LOCATION PRIVACY IN SENSOR NETWORKS
AGAINST A GLOBAL EAVESDROPPER
ABSTRACT
While many protocols for sensor network security provide confidentiality for the content
of messages, contextual information usually remains exposed. Such contextual information can
be exploited by an adversary to derive sensitive information such as the locations of monitored
objects and data sinks in the field. Attacks on these components can significantly undermine any
network application. Existing techniques defend the leakage of location information from a
limited adversary who can only observe network traffic in a small region. However, a stronger
adversary, the global eavesdropper, is realistic and can defeat these existing techniques. This
paper first formalizes the location privacy issues in sensor networks under this strong adversary
model and computes a lower bound on the communication overhead needed for achieving a
given level of location privacy. The paper then proposes two techniques to provide location
privacy to monitored objects (source location privacy) – periodic collection and source
simulation – and two techniques to provide location privacy to data sinks (sink location privacy)
– sink simulation and backbone flooding. These techniques provide trade-offs between privacy,
communication cost, and latency. Through analysis and simulation, we demonstrate that the
proposed techniques are efficient and effective for source and sink location privacy in sensor
networks.

EXISTING SYSTEM:
Location privacy has been an active area of research in recent years. In location-based services, a
user may want to retrieve location-based data without revealing her location. Techniques such as
k-anonymity and private information retrieval have been developed for this purpose. In pervasive
computing, users’ location privacy can be compromised by observing the wireless signals from
user devices. Random delay and dummy traffic have been suggested to mitigate these problems.
Location privacy in sensor networks also falls under the general framework of location privacy.
The adversary monitors the wireless transmissions to infer locations of critical infrastructure.
However, there are some challenges unique to sensor networks. First, sensor nodes are usually
battery-powered, which limits their functional lifetime. Second, a sensor network is often
significantly larger than the network in smart home or assisted living applications.
PROPOSED SYSTEM:
The proposed location privacy techniques in this paper have advantages and disadvantages when
compared with each other. We now briefly summarize our understanding of which solutions
should be used for different applications. The periodic collection and source simulation methods
can be used for providing
source location privacy. The periodic collection method provides the highest location privacy
and is hence useful when we are monitoring highly valuable objects. Additionally, the
communication cost – though high – does not increase with the number of monitored objects.
Thus, it is suitable for applications that collect data at a low rate from the network about many
objects. The source simulation method provides a trade-off between privacy and communication
costs. It is suitable for scenarios where (i) the object movement pattern can be properly modeled
and (ii) we need to collect real-time data from the network about the objects.
MODULES:

1. Client
2. Server
3. Roueters
4. Eavesdroppers
1. Client:
 Client enter the username and password to login
 Connect to the server.
 Select a file to transfer
 Using Connection, Destination nodes.
 Send the data to server via routers
 Close the connection.
2. Server:
 client will ask the request to server for connection
 At that time server will give the response to the client
 In server we want to select a location for receiving a file.
 Receiving data’s from client.
3. Router:

 It is an intermediate between the Server and Client.
 When Eavesdropper will try to hack the source and destination routers its give the
information that is source and destination having a more security it’s not possible
to hack we are providing a security to source and destination.
 Otherwise router forwards the packet to the next node.
4. Eavesdropper:
 Eavesdropper tries to hack the client and server information or data’s.
 Eavesdropper hack the router.
Hardware Requirements:
• System : Pentium IV 2.4 GHz.
• Hard Disk : 40 GB.
• Floppy Drive : 1.44 Mb.
• Monitor : 15 VGA Colour.
• Mouse : Logitech.
• Ram : 256 Mb.
Software Requirements:
• Operating System : - Windows Xp Professional.
• Coding Language : - Visual C# .Net.
• IDE :- Visual Studio .Net
SOFTWARE ENVIRONMENT

Introduction to .NET Framework:
The .NET Framework is a new computing platform that simplifies application
development in the highly distributed environment of the Internet. The .NET Framework is
designed to fulfill the following objectives:
 To provide a consistent object-oriented programming environment whether object code is
stored and executed locally, executed locally but Internet-distributed, or executed remotely.
 To provide a code-execution environment that minimizes software deployment and
versioning conflicts.
 To provide a code-execution environment that guarantees safe execution of code, including
code created by an unknown or semi-trusted third party.
 To provide a code-execution environment that eliminates the performance problems of
scripted or interpreted environments.
 To make the developer experience consistent across widely varying types of applications,
such as Windows-based applications and Web-based applications.
 To build all communication on industry standards to ensure that code based on the .NET
Framework can integrate with any other code.

The .NET Framework has two main components: the common language runtime and the
.NET Framework class library. The common language runtime is the foundation of the .NET
Framework. You can think of the runtime as an agent that manages code at execution time,
providing core services such as memory management, thread management, and Remoting, while
also enforcing strict type safety and other forms of code accuracy that ensure security and
robustness. In fact, the concept of code management is a fundamental principle of the runtime.
Code that targets the runtime is known as managed code, while code that does not target the
runtime is known as unmanaged code. The class library, the other main component of the .NET
Framework, is a comprehensive, object-oriented collection of reusable types that you can use to
develop applications ranging from traditional command-line or graphical user interface (GUI)
applications to applications based on the latest innovations provided by ASP.NET, such as Web
Forms and XML Web services.
The .NET Framework can be hosted by unmanaged components that load the common
language runtime into their processes and initiate the execution of managed code, thereby
creating a software environment that can exploit both managed and unmanaged features. The
.NET Framework not only provides several runtime hosts, but also supports the development of
third-party runtime hosts.
For example, ASP.NET hosts the runtime to provide a scalable, server-side environment
for managed code. ASP.NET works directly with the runtime to enable Web Forms applications
and XML Web services, both of which are discussed later in this topic.
Internet Explorer is an example of an unmanaged application that hosts the runtime (in
the form of a MIME type extension). Using Internet Explorer to host the runtime enables you to
embed managed components or Windows Forms controls in HTML documents. Hosting the
runtime in this way makes managed mobile code (similar
to Microsoft® ActiveX® controls) possible, but with significant improvements that only
managed code can offer, such as semi-trusted execution and secure isolated file storage.

The following illustration shows the relationship of the common language runtime and
the class library to your applications and to the overall system. The illustration also shows how
managed code operates within a larger architecture.
FEATURES OF THE COMMON LANGUAGE RUNTIME:
The common language runtime manages memory, thread execution, code execution, code
safety verification, compilation, and other system services. These features are intrinsic to the
managed code that runs on the common language runtime.
With regards to security, managed components are awarded varying degrees of trust,
depending on a number of factors that include their origin (such as the Internet, enterprise
network, or local computer). This means that a managed component might or might not be able
to perform file-access operations, registry-access operations, or other sensitive functions, even if
it is being used in the same active application.
The runtime enforces code access security. For example, users can trust that an
executable embedded in a Web page can play an animation on screen or sing a song, but cannot
access their personal data, file system, or network. The security features of the runtime thus
enable legitimate Internet-deployed software to be exceptionally featuring rich.
The runtime also enforces code robustness by implementing a strict type- and code-
verification infrastructure called the common type system (CTS). The CTS ensures that all
managed code is self-describing. The various Microsoft and third-party language compilers
Generate managed code that conforms to the CTS. This means that managed code can
consume other managed types and instances, while strictly enforcing type fidelity and type
safety.

In addition, the managed environment of the runtime eliminates many common software
issues. For example, the runtime automatically handles object layout and manages references to
objects, releasing them when they are no longer being used. This automatic memory
management resolves the two most common application errors, memory leaks and invalid
memory references.
The runtime also accelerates developer productivity. For example, programmers can
write applications in their development language of choice, yet take full advantage of the
runtime, the class library, and components written in other languages by other developers. Any
compiler vendor who chooses to target the runtime can do so. Language compilers that target the
.NET Framework make the features of the .NET Framework available to existing code written in
that language, greatly easing the migration process for existing applications.
While the runtime is designed for the software of the future, it also supports software of
today and yesterday. Interoperability between managed and unmanaged code enables developers
to continue to use necessary COM components and DLLs.
The runtime is designed to enhance performance. Although the common language
runtime provides many standard runtime services, managed code is never interpreted. A feature
called just-in-time (JIT) compiling enables all managed code to run in the native machine
language of the system on which it is executing. Meanwhile, the memory manager removes the
possibilities of fragmented memory and increases memory locality-of-reference to further
increase performance.
Finally, the runtime can be hosted by high-performance, server-side applications, such as
Microsoft® SQL Server™ and Internet Information Services (IIS). This infrastructure enables
you to use managed code to write your business logic, while still enjoying the superior
performance of the industry's best enterprise servers that support runtime hosting.

.NET FRAMEWORK CLASS LIBRARY:
The .NET Framework class library is a collection of reusable types that tightly integrate
with the common language runtime. The class library is object oriented, providing types from
which your own managed code can derive functionality. This not only makes the .NET
Framework types easy to use, but also reduces the time associated with learning new features of
the .NET Framework. In addition, third-party components can integrate seamlessly with classes
in the .NET Framework.
For example, the .NET Framework collection classes implement a set of interfaces that
you can use to develop your own collection classes. Your collection classes will blend
seamlessly with the classes in the .NET Framework.
As you would expect from an object-oriented class library, the .NET Framework types
enable you to accomplish a range of common programming tasks, including tasks such as string
management, data collection, database connectivity, and file access. In addition to these common
tasks, the class library includes types that support a variety of specialized development scenarios.
For example, you can use the .NET Framework to develop the following types of applications
and services:
 Console applications.
 Scripted or hosted applications.
 Windows GUI applications (Windows Forms).
 XML Web services.

 Windows services.
For example, the Windows Forms classes are a comprehensive set of reusable types
that vastly simplify Windows GUI development. If you write an ASP.NET Web Form
application, you can use the Web Forms classes.
CLIENT APPLICATION DEVELOPMENT:
Client applications are the closest to a traditional style of application in Windows-based
programming. These are the types of applications that display windows or forms on the desktop,
enabling a user to perform a task. Client applications include applications such as word
processors and spreadsheets, as well as custom business applications such as data-entry tools,
reporting tools, and so on. Client applications usually employ windows, menus, buttons, and
other GUI elements, and they likely access local resources such as the file system and peripherals
such as printers.
Another kind of client application is the traditional ActiveX control (now replaced by the
managed Windows Forms control) deployed over the Internet as a Web page. This application is
much like other client applications: it is executed natively, has access to local resources, and
includes graphical elements.
In the past, developers created such applications using C/C++ in conjunction with the Microsoft
Foundation Classes (MFC) or with a rapid application development (RAD) environment such as
Microsoft® Visual Basic®. The .NET Framework incorporates aspects of these existing products

into a single, consistent development environment that drastically simplifies the development of
client applications.
The Windows Forms classes contained in the .NET Framework are designed to be used for GUI
development. You can easily create command windows, buttons, menus, toolbars, and other
screen elements with the flexibility necessary to accommodate shifting business needs.
For example, the .NET Framework provides simple properties to adjust visual attributes
associated with forms. In some cases the underlying operating system does not support changing
these attributes directly, and in these cases the .NET Framework automatically recreates the
forms. This is one of many ways in which the .NET Framework integrates the developer
interface, making coding simpler and more consistent.
Unlike ActiveX controls, Windows Forms controls have semi-trusted access to a user's
computer. This means that binary or natively executing code can access some of the resources on
the user's system (such as GUI elements and limited file access) without being able to access or
compromise other resources. Because of code access security, many applications that once
needed to be installed on a user's system can now be safely deployed through the Web. Your
applications can implement the features of a local application while being deployed like a Web
page.
C#.Net for Windows Application
Overview of the .NET Framework
The .NET Framework is a managed type-safe environment for application development and
execution. The .NET Framework manages all aspects of your program’s execution. It allocates
memory for the storage of data and instructions, grants or denies the appropriate permissions to
your application, initiates and manages application execution, and manages the reallocation of

memory from resources that are no longer needed. The .NET Framework consists of two main
components: the common language runtime and the .NET Framework class library.
The common language runtime can be thought of as the environment that manages code
execution. It provides core services, such as code compilation, memory allocation, thread
management, and garbage collection. Through the common type system (CTS), it enforces strict
type-safety and ensures that code is executed in a safe environment by also enforcing code
access security.
The .NET Framework class library provides a collection of useful and reusable types that are
designed to integrate with the common language runtime. The types provided by the .NET
Framework are object-oriented and fully extensible, and they allow you to seamlessly integrate
your applications with the .NET Framework.
Languages and the .NET Framework
The .NET Framework is designed for cross-language compatibility, which means, simply, that
.NET components can interact with each other no matter what supported language they were
written in originally. So, an application written in Microsoft Visual Basic .NET might reference
a dynamic-link library (DLL) file written in Microsoft Visual C#, which in turn might access a
resource written in managed Microsoft Visual C++ or any other .NET language. This language
interoperability extends to full object-oriented inheritance. A Visual Basic .NET class might be
derived from a C# class, for example, or vice versa.
This level of cross-language compatibility is possible because of the common language runtime.
When a .NET application is compiled, it is converted from the language in which it was written
(Visual Basic .NET, C#, or any other .NET-compliant language) to Microsoft Intermediate
Language (MSIL or IL). MSIL is a low-level language that the common language runtime can
read and understand. Because all .NET executables and DLLs exist as MSIL, they can freely
interoperate. The Common Language Specification (CLS) defines the minimum standards to

which .NET language compilers must conform. Thus, the CLS ensures that any source code
successfully compiled by a .NET compiler can interoperate with the .NET Framework.
The CTS ensures type compatibility between .NET components. Because .NET applications are
converted to IL prior to deployment and execution, all primitive data types are represented as
.NET types. Thus, a Visual Basic Integer and a C# int are both represented in IL code as a
System.Int32. Because both languages use a common type system, it is possible to transfer data
between components and avoid time-consuming conversions or hard-to-find errors.
Visual Studio .NET ships with languages such as Visual Basic .NET, Visual C#, and Visual C++
with managed extensions, as well as the JScript scripting language. You can also write managed
code for the .NET Framework in other languages. Third-party tools and compilers exist for
Fortran, Cobol, Perl, and a host of other languages. All of these languages share the same cross-
language compatibility and inheritability. Thus, you can write code for the .NET Framework in
the language of your choice, and it will be able to interact with code written for the .NET
Framework in any other language.
.NET Framework Architecture

The Structure of a .NET Application
To understand how the common language runtime manages code execution, you must examine
the structure of a .NET application. The primary unit of a .NET application is the assembly. An
assembly is a self-describing collection of code, resources, and metadata. The assembly manifest
contains information about what is contained within the assembly. The assembly manifest
provides:
 Identity information, such as the assembly’s name and version number
 A list of all types exposed by the assembly
 A list of other assemblies required by the assembly
 A list of code access security instructions, including permissions required by the
assembly and permissions to be denied the assembly

Each assembly has one and only one assembly manifest, and it contains all the description
information for the assembly. However, the assembly manifest can be contained in its own file or
within one of the assembly’s modules.
An assembly contains one or more modules. A module contains the code that makes up your
application or library, and it contains metadata that describes that code. When you compile a
project into an assembly, your code is converted from high-level code to IL. Because all
managed code is first converted to IL code, applications written in different languages can easily
interact. For example, one developer might write an application in Visual C# that accesses a
DLL in Visual Basic .NET. Both resources will be converted to IL modules before being
executed, thus avoiding any language-incompatibility issues.
Each module also contains a number of types. Types are templates that describe a set of data
encapsulation and functionality. There are two kinds of types: reference types (classes) and value
types (structures). These types are discussed in greater detail in Lesson 2 of this chapter. Each
type is described to the common language runtime in the assembly manifest. A type can contain
fields, properties, and methods, each of which should be related to a common functionality. For
example, you might have a class that represents a bank account. It contains fields, properties, and
methods related to the functions needed to implement a bank account. A field represents storage
of a particular type of data. One field might store the name of an account holder, for example.
Properties are similar to fields, but properties usually provide some kind of validation when data
is set or retrieved. You might have a property that represents an account balance. When an
attempt is made to change the value, the property can check to see if the attempted change is
greater than a predetermined limit. If the value is greater than the limit, the property does not
allow the change. Methods represent behavior, such as actions taken on data stored within the
class or changes to the user interface. Continuing with the bank account example, you might
have a Transfer method that transfers a balance from a checking account to a savings account, or
an Alert method that warns users when their balances fall below a predetermined level.

CLR Execution Model
Compilation and Execution of a .NET Application
When you compile a .NET application, it is not compiled to binary machine code; rather, it is
converted to IL. This is the form that your deployed application takes—one or more assemblies
consisting of executable files and DLL files in IL form. At least one of these assemblies will
contain an executable file that has been designated as the entry point for the application.
When execution of your program begins, the first assembly is loaded into memory. At this point,
the common language runtime examines the assembly manifest and determines the requirements
to run the program. It examines security permissions requested by the assembly and compares
them with the system’s security policy. If the system’s security policy does not allow the
requested permissions, the application will not run. If the application passes the system’s security

policy, the common language runtime executes the code. It creates a process for the application
to run in and begins application execution. When execution starts, the first bit of code that needs
to be executed is loaded into memory and compiled into native binary code from IL by the
common language runtime’s Just-In-Time (JIT) compiler. Once compiled, the code is executed
and stored in memory as native code. Thus, each portion of code is compiled only once when an
application executes. Whenever program execution branches to code that has not yet run, the JIT
compiler compiles it ahead of execution and stores it in memory as binary code. This way,
application performance is maximized because only the parts of a program that are executed are
compiled.
2: The .NET Base Class Library
 The .NET base class library is a collection of object-oriented types and interfaces that
provide object models and services for many of the complex programming tasks you will
face. Most of the types presented by the .NET base class library are fully extensible,
allowing you to build types that incorporate your own functionality into your managed
code.
The .NET Framework base class library contains the base classes that provide many of the
services and objects you need when writing your applications. The class library is organized into
namespaces. A namespace is a logical grouping of types that perform related functions. For
example, the System.Windows.Forms namespace contains all the types that make up Windows
forms and the controls used in those forms.
Namespaces are logical groupings of related classes. The namespaces in the .NET base class
library are organized hierarchically. The root of the .NET Framework is the System namespace.
Other namespaces can be accessed with the period operator. A typical namespace construction
appears as follows:
System

System.Data
System.Data.SQLClient
The first example refers to the System namespace. The second refers to the System.Data
namespace. The third example refers to the System.Data.SQLClient namespace. Table 1.1
introduces some of the more commonly used .NET base class namespaces.
Table 1-1. Representative .NET Namespaces
Namespace Description
System
This namespace is the root for many of the low-level types required
by the .NET Framework. It is the root for primitive data types as well,
and it is the root for all the other namespaces in the .NET base class
library.
System.Collections
This namespace contains classes that represent a variety of different
container types, such as ArrayList, SortedList, Queue, and Stack. You
also can find abstract classes, such as CollectionBase, which are
useful for implementing your own collection functionality.
System.ComponentModel
This namespace contains classes involved in component creation and
containment, such as attributes, type converters, and license providers.
System.Data
This namespace contains classes required for database access and
manipulations, as well as additional namespaces used for data access.
System.Data.Common
This namespace contains a set of classes that are shared by the .NET
managed data providers.
System.Data.OleDb
This namespace contains classes that make up the managed data
provider for OLE DB data access.
System.Data.SQLClient
This namespace contains classes that are optimized for interacting
with Microsoft SQL Server.

Table 1-1. Representative .NET Namespaces
Namespace Description
System.Drawing
This namespace exposes GDI+ functionality and provides classes that
facilitate graphics rendering.
System.IO In this namespace, you will find types for handling file system I/O.
System.Math
This namespace is home to common mathematics functions such as
extracting roots and trigonometry.
System.Reflection
This namespace provides support for obtaining information and
dynamic creation of types at runtime.
System.Security
This namespace is home to types dealing with permissions,
cryptography, and code access security.
System.Threading
This namespace contains classes that facilitate the implementation of
multithreaded applications.
System.Windows.Forms
This namespace contains types involved in creating standard
Windows applications. Classes that represent forms and controls
reside here as well.
The namespace names are self-descriptive by design. Straightforward names make the .NET
Framework easy to use and allow you to rapidly familiarize yourself with its contents.
Reference Types and Value Types
Types in the .NET Framework come in two varieties: value types and reference types. The
primary difference between value types and reference types has to do with the way variable data
is accessed. To understand this difference, a little background on memory dynamics is required.
Application data memory is divided into two primary components, the stack and the heap. The
stack is an area of memory reserved by the application to run the program. The stack is

analogous to a stack of dinner plates. Plates are placed on the stack one on top of another. When
a plate is removed from the stack, it is always the last one to have been placed on top that is
removed first. So it is with program variables. When a function is called, all the variables used
by the function are pushed onto the stack. If that function calls additional functions, it pushes
additional variables onto the stack. When the most recently called function terminates, all of its
variables go out of scope (meaning that they are no longer available to the application) and are
popped off the stack. Memory consumed by those variables is then freed up, and program
execution continues.
The heap, on the other hand, is a separate area of memory reserved for the creation of reusable
objects. The common language runtime manages allocation of heap memory for objects and
controls the reclamation of memory from unused objects through garbage collection.
All the data associated with a value type is allocated on the stack. When a variable of a value
type goes out of scope, it is destroyed and its memory is reclaimed. A variable of a reference
type, on the other hand, exists in two memory locations. The actual object data is allocated on the
heap. A variable containing a pointer to that object is allocated on the stack. When that variable
is called by a function, it returns the memory address for the object to which it refers. When that
variable goes out of scope, the object reference is destroyed but the object itself is not. If any
other references to that object exist, the object remains intact. If the object is left without any
references, it is subject to garbage collection. (See Lesson 6 of this chapter.)
Examples of value types include primitives, such as Integer (int), Boolean (bool), Char (char),
and so on, as well as user-defined types such as Structure (struct) and Enumeration (enum).
Classes represent the majority of reference types. Other reference types include the interface,
delegate, and array types. Classes and structures are discussed in Lesson 3 of this chapter, and
other reference and value types are discussed in Chapter 3.
Using .NET Framework Types in Your Application

When you begin writing an application, you automatically begin with a reference to the .NET
Framework base class library. You reference it so that your application is aware of the base class
library and is able to create instances of the types represented by it.
Value Types
int myInteger;
This line tells the runtime to allocate the appropriate amount of memory to hold an integer
variable. Although this line creates the variable, it does not assign a value to it. You can assign a
value using the assignment operator, as follows:
myInteger = 42;
You can also choose to assign a value to a variable upon creation, as shown in this example:
int myInteger = 42;
Reference Types
Creating an instance of a type is a two-step process. The first step is to declare the variable as
that type, which allocates the appropriate amount of memory for that variable but does not
actually create the object. The following syntax declares an object:
System.Windows.Forms.Form myForm;
This line tells the runtime to set aside enough memory to hold a Form variable and assigns it the
name myForm, but it does not actually create the Form object in memory. The second step,
called instantiation, actually creates the object. An example of instantiation follows:

myForm = new System.Windows.Forms.Form();
This line makes a call to the constructor method of the type System.Windows.Forms.Form by
way of the New (new) keyword. The constructor is a special method that is invoked only at the
beginning of an object’s lifetime. It contains any code that must be executed for the object to
work (assigning values to properties, for example). If any parameters were required by the
constructor, they would be contained within the parentheses at the end of the line. The following
example shows declaration and instantiation of a hypothetical Widget class that requires a string
as a parameter in the constructor.
Widget myWidget;
myWidget = new Widget("This string is required by the constructor");
If desired, you can also combine both declaration and instantiation into a single statement. By
declaring and instantiating an object in the same line, you reserve the memory for the object and
immediately create the object that resides in that memory. Although there was a significant
performance penalty for this shortcut in previous versions of Visual Basic, Visual Basic .NET
and Visual C# are optimized to allow this behavior without any performance loss. The following
example shows the one-step declaration and instantiation of a new Form:
System.Windows.Forms.Form myForm = new
System.Windows.Forms.Form();
Both value types and reference types must be initialized before use. For class and structure fields
in Visual Basic .NET, types are initialized with default values on declaration. Numeric value
types (such as integer) and floating-point types are assigned zero; Boolean variables are assigned
False; and reference types are assigned to a null reference.
In C#, variables of a reference type have a default value of null. It is recommended that you do
not rely on the default value. These variables should not be used until they have been initialized.

Using Value Type and Reference Type Variables
A variable that represents a value type contains all the data represented by that type. A variable
that represents a reference type contains a reference to a particular object. This distinction is
important. Consider the following example:
int x, y;
x = 15;
y = x;
x = 30;
// What is the value of y?
In this example, two integer variables named x and y are created. X is assigned a value of 15, and
then y is assigned the value of x. Next the value of x is changed to 30, and the question is posed:
what is the value of y? The answer to this question might seem obvious, and it is y = 15 because
x and y are two separate variables and have no effect on each other when changed. When the line
y = x is encountered, the value of x is copied to the value of y, and there is no further connection
between the two variables.
This situation changes, however, in the case of reference types. Let’s reconsider the previous
example using a reference type (Form) instead of a value type.
System.Windows.Forms.Form x,y;
x = new System.Windows.Forms.Form();
x.Text = "This is Form 1";
y = x;
x.Text = "This is Form 2";
// What value does y.Text return?

What value does y.Text return? This time, the answer is less obvious. Because
System.Windows.Forms.Form is a reference type, the variable x does not actually contain a
Form; rather, it points to an instance of a Form. When the line y = x is encountered, the runtime
copies the reference from variable x to y. Thus, the variables x and y now point to the same
instance of Form. Because these two variables refer to the same instance of the object, they will
return the same values for properties of that object. Thus, y.Text returns ―This is Form 2‖.
The Imports and Using Statements
Up to this point of the chapter, if you wanted to access a type in the .NET Framework base class
library, you had to use the full name of the type, including every namespace to which it
belonged. For example:
System.Windows.Forms.Form
This is called the fully-qualified name, meaning it refers both to the class and to the namespace
in which it can be found. You can make your development environment ―aware‖ of various
namespaces by using the Imports (Visual Basic .NET) or using (Visual C#) statement. This
technique allows you to refer to a type using only its generic name and to omit the qualifying
namespaces. Thus, you could refer to System.Windows.Forms.Form as simply Form. In Visual
Basic .NET, the Imports statement must be placed at the top of the code window, preceding any
other statement (except Option). In Visual C#, the using statement must occur before any other
namespace element, such as a class or struct. This example demonstrates use of this statement:
using System.Windows.Forms;
When two types of the same name exist in more than one imported namespace, you must use the
fully qualified name to avoid a naming conflict. Thus, if you are using MyNameSpaceOne and
MyNameSpaceTwo, and each contains a Widget class, you would have to refer to
MyNameSpaceOne.Widget or MyNameSpaceTwo.Widget to ensure the correct result.

In C#, you can resolve namespace conflicts such as these by creating an alias. An alias allows
you to choose one name to refer to another class. You create an alias using the using keyword, as
shown below:
using myAlias = MyNameSpaceTwo.Widget;
After implementing an alias, you can use it in code to represent the aliased class. For example:
// You can now refer to MyNameSpaceTwo as myAlias. The
// following two lines produce the same result:
MyNameSpaceTwo.Widget anotherWidget = new MyNameSpaceTwo.Widget() ;
myAlias anotherWidget = new myAlias() ;
You cannot create aliases for types in this manner in Visual Basic .NET.
Referencing External Libraries
You might want to use class libraries not contained by the .NET Framework, such as libraries
developed by third-party vendors or libraries you developed. To access these external libraries,
you must create a reference.
To create a reference to an external library
1. In the Solution Explorer, right-click the References node of your project.
2. From the pop-up menu, choose Add Reference. The Add Reference dialog box appears.
3. Choose the appropriate tab for the library you want to reference. .NET libraries are
available on the .NET tab. Legacy COM libraries appear on the COM tab, and local
Visual Studio projects appear on the Projects tab.
4. Locate the library you want to reference, and double-click it to add it to the Selected
components box. Click OK to confirm the choice of that reference.

Introduction to Object-Oriented Programming
Programming in the .NET Framework environment is done with objects. Objects are
programmatic constructs that represent packages of related data and functionality. Objects are
self-contained and expose specific functionality to the rest of the application environment
without detailing the inner workings of the object itself. Objects are created from a template
called a class. The .NET base class library provides a set of classes from which you can create
objects in your applications. You also can use the Microsoft Visual Studio programming
environment to create your own classes. This lesson introduces you to the concepts associated
with object-oriented programming.
Objects, Members, and Abstraction
An object is a programmatic construct that represents something. In the real world, objects are
cars, bicycles, laptop computers, and so on. Each of these items exposes specific functionality
and has specific properties. In your application, an object might be a form, a control such as a
button, a database connection, or any of a number of other constructs. Each object is a complete
functional unit, and contains all of the data and exposes all of the functionality required to fulfill
its purpose. The ability of programmatic objects to represent real-world objects is called
abstraction.
Classes Are Templates for Objects
Classes can be thought of as blueprints for objects: they define all of the members of an object,
define the behavior of an object, and set initial values for data when appropriate. When a class is

instantiated, an in-memory instance of that class is created. This instance is called an object. To
review, a class is instantiated using the New (new) keyword as follows:
When an instance of a class is created, a copy of the instance data defined by that class is created
in memory and assigned to the reference variable. Individual instances of a class are independent
of one another and represent separate programmatic constructs. There is generally no limit to
how many copies of a single class can be instantiated at any time. To use a real-world analogy, if
a car is an object, the plans for the car are the class. The plans can be used to make any number
of cars, and changes to a single car do not, for the most part, affect any other cars.
Objects and Members
Objects are composed of members. Members are properties, fields, methods, and events, and
they represent the data and functionality that comprise the object. Fields and properties represent
data members of an object. Methods are actions the object can perform, and events are
notifications an object receives from or sends to other objects when activity happens in the
application.
To continue with the real-world example of a car, consider that a Car object has fields and
properties, such as Color, Make, Model, Age, GasLevel, and so on. These are the data that
describe the state of the object. A Car object might also expose several methods, such as
Accelerate, ShiftGears, or Turn. The methods represent behaviors the object can execute. And
events represent notifications. For example, a Car object might receive an EngineOverheating
event from its Engine object, or it might raise a Crash event when interacting with a Tree object.
Object Models
Simple objects might consist of only a few properties, methods, and perhaps an event or two.
More complex objects might require numerous properties and methods and possibly even
subordinate objects. Objects can contain and expose other objects as members. For example, the

TextBox control exposes a Font property, which consists of a Font object. Similarly, every
instance of the Form class contains and exposes a Controls collection that comprises all of the
controls contained by the form. The object model defines the hierarchy of contained objects that
form the structure of an object.
An object model is a hierarchical organization of subordinate objects contained and exposed
within a main object. To illustrate, let’s revisit the example of a car as an object. A car is a single
object, but it also consists of subordinate objects. A Car object might contain an Engine object,
four Wheel objects, a Transmission object, and so on. The composition of these subordinate
objects directly affects how the Car object functions as a whole. For example, if the Cylinders
property of the Engine subordinate object is equal to 4, the Car will behave differently than a Car
whose Engine has a Cylinders property value of 8. Contained objects can have subordinate
objects of their own. For example, the contained Engine object might contain several SparkPlug
objects.
Encapsulation
Encapsulation is the concept that implementation of an object is independent of its interface. Put
another way, an application interacts with an object through its interface, which consists of its
public properties and methods. As long as this interface remains constant, the application can
continue to interact with the component, even if implementation of the interface was completely
rewritten between versions.
Objects should only interact with other objects through their public methods and properties.
Thus, objects should contain all of the data they require, as well as all of the functionality that
works with that data. The internal data of an object should never be exposed in the interface;
thus, fields rarely should be Public (public).
Returning to the Car example. If a Car object interacts with a Driver object, the Car interface
might consist of a GoForward method, a GoBackward method, and a Stop method. This is all the

information that the Driver needs to interact with the Car. The Car might contain an Engine
object, for example, but the Driver doesn’t need to know about the Engine object—all the Driver
cares about is that the methods can be called and that they return the appropriate values. Thus, if
one Engine object is exchanged for another, it makes no difference to the Driver as long as the
interface continues to function correctly.
Polymorphism
Polymorphism is the ability of different classes to provide different implementations of the same
public interfaces. In other words, polymorphism allows methods and properties of an object to be
called without regard for the particular implementation of those members. For example, a Driver
object can interact with a Car object through the Car public interface. If another object, such as a
Truck object or a SportsCar object, exposes the same public interface, the Driver object can
interact with them without regard to the specific implementation of that interface. There are two
principal ways through which polymorphism can be provided: interface polymorphism and
inheritance polymorphism.
Interface Polymorphism
An interface is a contract for behavior. Essentially, it defines the members a class should
implement, but states nothing at all about the details of that implementation. An object can
implement many different interfaces, and many diverse classes can implement the same
interface. All objects implementing the same interface are capable of interacting with other
objects through that interface. For example, the Car object in the previous examples might
implement the IDrivable interface (by convention, interfaces usually begin with I), which
specifies the GoForward, GoBackward, and Halt methods. Other classes, such as Truck, Forklift,
or Boat might implement this interface and thus are able to interact with the Driver object. The
Driver object is unaware of which interface implementation it is interacting with; it is only aware
of the interface itself. Interface polymorphism is discussed in detail in Lesson 3.

Inheritance Polymorphism
Inheritance allows you to incorporate the functionality of a previously defined class into a new
class and implement different members as needed. A class that inherits another class is said to
derive from that class, or to inherit from that class. A class can directly inherit from only one
class, which is called the base class. The new class has the same members as the base class, and
additional members can be added as needed. Additionally, the implementation of base members
can be changed in the new class by overriding the base class implementation. Inherited classes
retain all the characteristics of the base class and can interact with other objects as though they
were instances of the base class. For example, if the Car class is the base class, a derived class
might be SportsCar. The SportsCar class might be the base class for another derived class, the
ConvertibleSportsCar. Each newly derived class might implement additional members, but the
functionality defined in the original Car class is retained.
4.2 FEATURES OF SQL-SERVER
The OLAP Services feature available in SQL Server version 7.0 is
Now called SQL Server 2000 Analysis Services. The term OLAP Services has
Been replaced with the term Analysis Services. Analysis Services also includes
a new data mining
Component. The Repository component available in SQL Server version 7.0 is
Now Called Microsoft SQL Server 2000 Meta Data Services. References to the
Component Now use the term Meta Data Services. The term repository is used
Only in Reference to The repository engine within Meta Data Services
SQL-SERVER database consist of six type of objects,

They are,
 TABLE
 QUERY
 FORM
 REPORT
 MACRO
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.
FORMS:
A form is used to view and edit information in the database record by
Record .A Form displays only the information we want to see in the way we
Want to see it. Forms Use the familiar controls such as textboxes and
Checkboxes. This makes viewing and Entering data easy.
Views of Form:
We can work with forms in several primarily there are two views,
They are,
1. Design View
2. Form View
Design View
To build or modify the structure of a form, we work in forms
Design View. We can add control to the form that is bound to fields in a table
Or query, Includes textboxes, option buttons, graphs and pictures.
Form View
The form view which display the whole design of the form.

REPORT:
A report is used to vies and print information from the database. The
Report can ground records into many levels and compute totals and average by
Checking Values from many records at once. Also the report is attractive and
Distinctive because we have control over the size and appearance of it.
SYSTEM FLOW DIAGRAM
- Multi path
R - Router
R
R
ServerClient

Level1: (Client):
R R
HACKER
Client
Login
Connect

Level2: (Server):
Level3: (Router):
Server
Detail
s
Receive

Level4: (Hacker):
Router
List
Connect
Hack Info
Hacker
Select
Hack info
Hack

4. SYSTEM DESIGN
INTRODUCTION:
Software design sits at the technical kernel of the software engineering process and is
applied regardless of the development paradigm and area of application. Design is the first step
in the development phase for any engineered product or system. The designer’s goal is to

produce a model or representation of an entity that will later be built. Beginning, once system
requirement have been specified and analyzed, system design is the first of the three technical
activities -design, code and test that is required to build and verify software.
The importance can be stated with a single word ―Quality‖. Design is the place where
quality is fostered in software development. Design provides us with representations of software
that can assess for quality. Design is the only way that we can accurately translate a customer’s
view into a finished software product or system. Software design serves as a foundation for all
the software engineering steps that follow. Without a strong design we risk building an unstable
system – one that will be difficult to test, one whose quality cannot be assessed until the last
stage.
During design, progressive refinement of data structure, program structure, and
procedural details are developed reviewed and documented. System design can be viewed from
either technical or project management perspective. From the technical point of view, design is
comprised of four activities – architectural design, data structure design, interface design and
procedural design.
4.1 UML DIAGRAMS

The Unified Modeling language (UML) is a standard language for writing software
blueprints. The UML may be used to visualize, specify, construct and document the artifacts of a
software-intensive system.
The UML is a language for:
 Visualizing
 Specifying
 Constructing
 Documenting
Visualizing:
There are some things about a software system you can’t understand unless you build
models that transcend the textual programming language.
The UML is such a graphical language.
Specifying:
Specifying means building models that are precise, unambiguous, and complete. In
particular, the UML addresses the specification of all the important analysis, design, and
implementation decisions that must be made in developing and deploying a software-intensive
system.
Constructing:
The UML is not a visual programming language, but its models can be directly connected
to a variety of programming languages.

Documenting:
The UML addresses the documentation of a system’s architecture and all of its details. The
UML also provides a language for expressing requirements and for tests.
Conceptual Model of the UML:
You need to form a conceptual model of the language, and this requires learning three
major elements:
 UML’s basic building blocks.
 Rules of the UML.
 Common Mechanisms in the UML.
Building Blocks of the UML:
Three kinds of building blocks:
1. Things.
2. Relationships.
3. Diagrams.
Diagrams in the UML:
A diagram is the graphical presentation of a set of elements, most often rendered as a
connected graph of vertices (things) and arcs (relationships).

UML includes nine such diagrams:
1. Class diagram.
2. Object diagram.
3. Use case diagram.
4. Sequence diagram.
5. Collaboration diagram.
6. State chart diagram.
7. Activity diagram.
8. Component diagram.
9. Deployment diagram.
Rules of the UML:
The UML has semantic rules for
 Names What you can call things, relationships, and diagrams.
 Scope The context that gives specific meaning to a name.
 Visibility How those names can be seen and used by others.
 Integrity How things properly and consistently relate to one another.
 Execution What it means to run or simulate a dynamic model.
4.1.1 USECASE DIAGRAMS :

A use case diagram shows a set of use cases and actors and their relationships. Use case
diagram address the static use case view of a system. These diagrams are especially important in
organizing and modeling the behaviors of a system.
The use case concept was introduced by ivar jacobson in the object oriented software
engineering (oose) method. The functionality of a system is described in a number of different
use cases, each of which represents a specific flow of events in the system.
a use case corresponds to a sequence of transactions, in which each transaction is invoked
from outside the system (actors) and engages internal objects to interact with one another and
with the system’s surroundings. In essence, the use-case model defines the outside (actors) and
inside (use case) of the system’s behavior. Use cases represent specific flows of events in the
system. The use cases are initiated by actors and describe the flow of events that these actors are
set off.
an actor is anything that interacts with a use case. It could be a human user, external
hardware, or another system. An actor represents a category rather than a physical user. A use
case diagram is a graph of actors, a set of use cases enclosed by a system boundary,
communication (participation) associations between the actors and the use cases, and
generalization among the use cases.
FIGURE : USECASE DIAGRAM

Protecting location privacy in sensor networks against a global eavesdropper

4.1.2 SEQUENCE DIAGRAM:
A sequence diagram is an interaction diagram that emphasizes the time ordering of the
messages. Graphically, a sequence diagram is a table that shows objects arranged along the X-
axis and messages, ordered in increasing time, along the Y-axis.
Typically you place the object that initiates the interaction at the left and increasingly
more sub-routine objects to the right. Next, you place the messages that these objects send and
receive along the Y-axis, in order of increasing time from top to the bottom. This gives the
reader a clear visual cue to the flow of control over time.
A sequence diagram commonly contains:
 Objects
 Object Life Line
 Focus of Control

4.1.3 COLLABORATION DIAGRAM:
A collaboration diagram is an interaction diagram that emphasizes the structural
organization of the objects that send and receive messages.

FIGURE : COLLABARATION DIAGRAM

4.1.4 CLASS DIAGRAM:
Class diagrams are the most common diagrams found in modeling object-oriented
systems. A class diagram shows a set of classes, interfaces, and collaborations and their
relationships. Graphically, a class diagram is a collection of vertices and arcs. Class Diagrams
commonly contain the following things:
 Classes
 Interfaces
 Collaborations
Dependency, generalization and association relationship..
FIGURE : CLASS DIAGRAM

4.1.5 ACTIVITY DIAGRAM:
Activity diagrams are typically used for business process modeling, for modeling the
logic captured by a single use case or usage scenario, or for modeling the detailed logic of a
business rule. Although UML activity diagrams could potentially model the internal logic of a
complex operation it would be far better to simply rewrite the operation so that it is simple
enough that you don’t require an activity diagram. In many ways UML activity diagrams are the
object-oriented equivalent of flow charts and data flow diagrams (DFDs) from structured
development.

An Activity Diagram is essentially a flow chart showing flow of control from activity to
activity. They are used to model the dynamic aspects of as system. They can also be used to
model the flow of an object as it moves from state to state at different points in the flow of
control.
An activity is an ongoing non-atomic execution with in a State machine. Activities
ultimately result in some action, which is made up of executable atomic computations that result
in a change of state of distinguishes a use case diagram from all other kinds of diagrams is its
particular content.
Activity diagrams commonly contain:
 Initial Node
 Fork
 Start & End Symbol
 Joins
 Decision
 Condition
 Merge
In this project different activity diagrams are designed. The activity diagrams of admin are given.

Conclusion:
Prior work on location privacy in sensor networks assumed a local eavesdropper. This
assumption is unrealistic given a well-funded, highly-motivated attacker. In this paper, we
formalized the location privacy issues under a global eavesdropper and estimated the minimum
average communication overhead needed to achieve a given level of privacy. We also presented
techniques to provide location privacy to objects and sinks against a global eavesdropper. We
used analysis and simulation to show how well these techniques perform in dealing with a global
eavesdropper. There are a number of directions that worth studying in the future. First, in this
paper, we assume that the global eavesdropper does not compromise sensor nodes; he only
performs traffic analysis without looking at contents of packets. However, in practice, the global
eavesdropper may be able to compromise a subset of the sensor nodes in the field and perform
traffic analysis with additional nowledge from insiders. This presents interesting challenges to
our methods. Second, some applications may require both source and sink location privacy. It
will be interesting to investigate issues arising from integrating the source and sink location
privacy techniques. Third, while we believe that it is possible for a well-funded and technically-
savvy adversary to obtain a complete picture of network traffic, we recognize that complete

coverage and perfect traffic analysis may be beyond the reach of some attackers. It is thus very
interesting to study location privacy issues when the adversary can see only a fraction of the
network traffic and must deal with the complexities of wireless signals. Finally, it takes time for
the observations made by the adversarial network to reach the adversary for analysis and
reaction. Studying the impact of such ―delayed‖ analysis and reaction will be another interesting
research direction.
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location queries in mobile environments with privacygrid.
In Proceedings of the International Conference on World-Wide
Web (WWW), 2008.
[3] BlueRadios Inc. Order and price info. http://www.blueradios.
com/orderinfo.htm. Accessed in February 2006.
[4] Bela Bollobas, David Gamarnik, Oliver Riordan, and Benny
Sudakov. On the value of a random minimum weight steiner
tree, 2004.
[5] H. Chan, A. Perrig, and D. Song. Random key predistribution
schemes for sensor networks. In IEEE Symposium on Security

and Privacy (S&P), pages 197–213, May 2003.
[6] J. Deng, R. Han, and S.Mishra. Enhancing base station security
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analysis strategies for wireless sensor networks. In 2004
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(DSN), June 2004.
[8] J. Deng, R. Han, and S. Mishra. Decorrelating wireless sensor
network traffic to inhibit traffic analysis attacks. Elsevier
Pervasive and Mobile Computing Journal, Special Issue on Security
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[9] L. Eschenauer and V. D. Gligor. A key-management scheme
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pages 41–47, November 2002.
[10] G. Ghinita, P. Kalnis, A. Khoshgozaran, C. Shahabi, and K. L.
Tan. Private queries in location based services: anonymizers
are not necessary. In Proceedings of the ACM SIGMOD international
conference on Management of data (SIGMOD), 2008.
[11] H. Gupta, Z. Zhou, S. Das, and Q. Gu. Connected sensor
cover: self-organization of sensor networks for efficient query
execution. IEEE/ACM Trans. Netw., 14(1):55–67, 2006.
[12] J. Hill, M. Horton, R. Kling, and L. Krishnamurthy. The
platforms enabling wireless sensor networks. Commun. ACM,
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[13] Y. Jian, S. Chen, Z. Zhang, and L. Zhang. Protecting receiverlocation
privacy in wireless sensor networks. In Proceedings
of IEEE International Conference on Computer Communications
(INFOCOM), pages 1955–1963, May 2007.

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