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AN EFFICIENT KEY MANAGEMENT SCHEME (KTR) FOR SECURE DATA ACCESS

CONTROL IN WIRELESS BROADCAST SERVICES

1. INTRODUCTION

With the ever growing popularity of smart mobile devices along with the rapid

advent of wireless technology, there has been an increasing interest in wireless data

services among both industrial and academic communities in recent years. Among

various approaches, broadcast allows a very efficient usage of the scarce wireless

bandwidth, because it allows simultaneous access by an arbitrary number of mobile

clients . Wireless data broadcast services have been available as commercial products

for many years. We propose a new key management scheme, namely key tree reuse

(KTR, based on two important observations! (" users who subscribe to multiple

programs can be captured by a shared key tree, and (# old keys can be reused to save

rekey cost without compromising security. KTR has two components! shared key tree

and shared key management.KTR combines the advantages of both shared key tree

and critical key. Among all schemes, it has a light communication overhead (i.e. its

average rekey message si$e per event is the least or close to the smallest, incurs less

computation and power consumption on mobile devices than the other schemes (i.e.

its average number of decryption per event per user is the smallest, and re%uires least

storage in mobile devices (i.e. its average number of keys held per user is the

smallest. &ecause a mobile receiver generally only has limited resources, such an

overhead saving can greatly benefit the receivers so that they can have a longer

working duration and more computation capacity to process broadcast data.

We evaluate the storage demand on mobile devices, which is measured as the

average number of keys held by each user. 'ne goal is to save storage by reducing the

number of keys each user needs to hold. ince KTR makes programs share keys, KTR

saves storage for a user when the user )oins a tree shared by more programs. As

analy$ed before, the structure that programs share trees determines the number of

keys that can be saved. *owever, since users may favor some subscriptions, users

may concentrate in some trees. +or users subscribing to single programs, KTR has no

advantage over K*.

-n broadcast services, the basic data unit is data item, such as a piece of news

or a stock price. ata items are grouped into programs and a user specifies which

programs he would like to access. Typical programs could be weather, news, stock

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his subscription period. 6onse%uently, a critical issue remains, i.e. how can we

efficiently manage keys when a user )oins5leaves5changes the service without

compromising security and interrupting the operations of other users7 Regarding

uni%ue features of broadcast services, we are interested in new key management

schemes that can simultaneously provide security, efficiency and fle/ibility. A

broadcast service generally provides many programs8 at the same time, users may

like to subscribe to an arbitrary set of programs. We envision that a user should be

able to fle/ibly subscribe5unsubscribe to any program of interests and make changes

to his subscription at any time. *ence, in addition to security and efficiency,

fle/ibility that a user can customi$e his subscription at anytime is an indispensable

feature of key management in broadcast services to support user subscriptions.

4evertheless, directly applying K* in broadcast services is not the most efficient

approach. -n broadcast services, a program is e%uivalent to a multicast group, and

users who subscribe to one program form a group. -ntuitively, we could manage a

separate set of keys for each program, and ask a user to hold m sets of keys for his

subscribed m programs. This straight forward approach is inefficient for users

subscribing to many programs. -f users could use the same set of keys for multiple

programs, there would be fewer re%uirements for users to handle keys. +urthermore,

when a user changes subscription, we argue that it is unnecessary to change keys for

the programs to which the user is still subscribing, as long as security can be ensured.

-n this way, rekey cost can be reduced and fewer users will be affected. Therefore, we

propose a new key management scheme, namely key tree reuse (KTR.

KTR has two components! shared key tree and shared key management, and

its contribution includes the following aspects.

+irst, the proposed scheme takes advantage of a fact in broadcast services!

many users subscribe to multiple programs simultaneously. -n other words, programs

overlap with each other in terms of users. &ecause e/isting approaches manage keys

by separating programs, they turn to be demanding for the users who subscribe to

many programs. *ence, this study contributes to the literature a new scheme (namely

KTR to better support subscriptions of multiple programs by e/ploiting the

overlapping among programs. KTR let multiple programs share the same set of keys

for the users who subscribe to these programs. KTR thus inherently enables users to

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handle fewer keys and reduces the demands of storage and processing power on

resource3limited mobile devices. econd, since multiple programs are allowed to

share the same set of keys, a critical issue is how to manage shared keys efficiently

and securely. We find that when keys need to be distributed to a user, it is unnecessary

to change all of them. -n many circumstances, when a user subscribes to new

programs or unsubscribes to some programs, a large portion of keys that the user will

hold in his new subscription can be reused without compromising security. KTR is a

novel approach for determining which keys need to be changed and for finding the

minimum number of keys that must be changed. *ence, KTR efficiently handles the

rekey of the shared keys and minimi$es the rekey costs associated with possible

subscriptions. 'ur simulations show that critical keys can be employed in logical key

hierarchy schemes key management for multi cast issues and multi cast distribution

and multi cast key distribution to improve their performance.

Two categories of key management schemes in the literature may be applied in

broadcast services! (" logic key hierarchy (K* based techni%ues proposed for

multicast services8 and (# broadcast encryption techni%ues in current broadcast

services (such as satellite T9. We notice that current broadcast encryption

techni%ues, including &-, igicipher, -rdeto, 4agravision, 9iaccess, and

9ideo:uard, cannot in fact support fle/ibility. They normally re%uire users to possess

decryption bo/es to receive the subscribed programs, and the broadcast services can

only provide to users a few packages, each of which includes a fi/ed set of programs

(T9 channels. 1sers cannot select individual programs within a package. -f a user

wants to change his subscription, the user needs to re%uest another decryption bo/ that

can decrypt the subscribed programs. *ence, in this paper, we will focus on adapting

more fle/ible K*3based techni%ues. 4evertheless, directly applying K* in

broadcast services is not the most efficient approach. -n broadcast services, a program

is e%uivalent to a multicast group, and users who subscribe to one program form a

group. -ntuitively, we could manage a separate set of keys for each program, and ask a

user to hold m sets of keys for his subscribed m programs. This straightforward

approach is inefficient for users subscribing to many programs. -f users could use the

same set of keys for multiple programs, there would be fewer re%uirements for users

to handle keys. +urthermore, when a user changes subscription, we argue that it is

unnecessary to change keys for the programs to which the user is still subscribing, asIT, MITS, 2011

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long as security can be ensured. -n this way, rekey cost can be reduced and fewer

users will be affected. Therefore, we propose a new key management scheme, namely

key tree reuse (KTR, based on two important observations! (" users who subscribe

to multiple programs can be captured by a shared key tree, and (# old keys can be

reused to save rekey cost without compromising security. KTR has two components!

shared key tree and shared key management.

1.1 SYMMETRIC KEY MANAGEMENT ALGORITHM:

ymmetric key management is the key management of cryptographic

symmetric encryption keys. -n a symmetric key algorithm the keys involved are

identical for both encrypting and decrypting a message. uch keys must be chosencarefully, and distributed and stored securely. -n any system there may be multiple

keys for various purposes. Accordingly, key management is central to the successful

and secure use of symmetric key algorithms.

The main characteristics of symmetric key management are!

key generation

key e/change

key storage

key usage

Key generation

Key generation is part of key management. -t is important, for some

algorithms have weak keys which make cryptanalysis easier, even much easier. ;,

the 1 :overnment approved cipher standard has, for instance, four known weak

keys. These keys must be known, if they e/ist, and eliminated from the pool of

possible keys. 'therwise, the chief re%uirement of a key for symmetric cipher use is

unpredictability, specifically to any potential attacker. This is somewhat like the case

of passwords. &ecause this is e%uivalent to high entropy, and because keys can be

thought of as a string of bits, the usual techni%ue for generating a key is to select one

from a pool of binary random numbers.

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;%uivalently, one may say that the output of a key generating function should

not support a conclusion about the input.-n either case, the %uality of the random

number generator used should be as high as possible. This is difficult to achieve in

practice. s

code clerk was of this type, referring to a page in a statistical manual, though it was in

fact a code. The :erman Army ;nigma symmetric encryption key was a mi/ed type

early in its use8 the key was a combination of secretly distributed key schedules and a

user chosen session key component for each message.

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-n more modern systems, such as 'pen 2:2 compatible systems, a session

key for a symmetric key algorithm is distributed encrypted by an asymmetric key

algorithm. This approach avoids even the necessity for using a key e/change protocol

like iffie3*ellman key e/change.

A more comple/ method of key e/change involves encapsulating one key

within another. -t>s not clear that this increase security for if one key can be securely

e/changed (the encapsulating key, the encapsulated key can presumably be as well.

This techni%ue is usually termed Key Wrap. A common techni%ue uses &lock

ciphers and cryptographic hash functions.

A related method, also more complicated, is to e/change a master key(sometimes termed a root key, and, as needed, derive subsidiary keys, possible for

each session, from that key. As with the key wrapping scheme above, this scheme also

offers no obvious benefit, for if the master key can be distributed securely, so might

the subsidiary keys. When the availability of secure e/change is intermittent, or when

keys must be related to each other (i.e., departmental keys are tied to divisional keys,

and individual keys tied to departmental keys this techni%ue may be useful. *owever,

tying keys to each other increase the damage which may result from a security breach

as attackers will learn something about more than one key. This reduces entropy, with

regard to an attacker, for each key involved.

Key "torage

*owever distributed, symmetric keys must be stored securely to maintain

communications security. There are various techni%ues in use to assist with this.

ikely the most common is that an encryption application manages keys for the user

and depends on an access password to control use of the key. -t is rare to use keys in

>raw> form, that is as a string of bits, most probably because such strings often

generate mistakes when handled by humans.

Key #"e

The ma)or issue is length of key use, and therefore fre%uency of replacement.

&ecause it increases any attackers re%uired effort, keys should be fre%uently changed.

This also limits loss of information, as the number of stored encrypted messages

which will become readable when a key is found will be decrease as the fre%uency of

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key change increases. *istorically, symmetric keys have been used for long periods in

situations in which key e/change was very difficult or only possible intermittently.

-deally, the symmetric key should change with each message or interaction, so that

only that message will become readable if the key is learned (e.g., stolen,

cryptanaly$ed, or social engineered.

Literat#re "#r$ey:

iterature surveyis the most important step in software development process.

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

company strength. 'nce these things r satisfied, ten ne/t step is to determine which

operating system and language can be used for developing the tool. 'nce theprogrammersstart building the tool the programmers need lot of e/ternal support.

This support can be obtained from senior programmers, frombookor from websites.

&efore building the system the above consideration r taken into account for

developing the proposed system.

Logia% Key Hierar!y

ecure key management for wireless broadcast is closely related to secure

group key management in networking . ogical key hierarchy (K* is proposed in

that uses a key tree (depicted in +igure for each group of users who subscribe the

same program. The root (top node of the tree is the data encryption key (;K of the

program. ;ach leaf (bottom node in the tree represents an individual key (-K of a

user that is only shared between the system and the user. 'ther keys in the tree,

namely key distribution keys (KKs, are used to encrypt new ;Ks and KKs. A

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http://www.blurtit.com/q876299.htmlhttp://www.blurtit.com/q876299.htmlhttp://www.blurtit.com/q876299.htmlhttp://www.blurtit.com/q876299.htmlhttp://www.blurtit.com/q876299.htmlhttp://www.blurtit.com/q876299.htmlhttp://www.blurtit.com/q876299.htmlhttp://www.blurtit.com/q876299.html


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user only knows the keys along the path from the leaf of the user to the root of the key

tree proposes a combination of key tree and iffie3*ellman key e/change to provide a

simple and fault3tolerant key agreement for collaborative groups. reduces the number

of rekey messages, while , improve the reliability of rekey management. &alanced

and unbalanced key trees are discussed in and . 2eriodic group re3keying is studied in

to reduce the rekey cost for groups with fre%uent )oins and leaves.

IN&UT DESIGN

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

comprises the developing specification and procedures for data preparation and those

steps are necessary to put transaction data in to a usable form for processing can beachieved by inspecting the computer to read data from a written or printed document

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

of input focuses on controlling the amount of input re%uired, controlling the errors,

avoiding delay, avoiding e/tra steps and keeping the process simple. The input is

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

privacy. -nput esign considered the following things!

What data should be given as input7

*ow the data should be arranged or coded7

The dialog to guide the operating personnel in providing input.


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*. SYSTEM ANALYSIS

*.1E+ISTING SYSTEM:

+irst, the proposed scheme takes advantage of a fact in broadcast services!

many users subscribe to multiple programs simultaneously. -n other words, programs



many programs.

econd, since multiple programs are allowed to share the same set of keys, a

critical issue is how to manage shared keys efficiently and securely. -n many

circumstances, when a user subscribes to new programs or unsubscribe to some

programs, a large portion of keys that the user will hold in his new subscription can be

reused without compromising security.

*.* &RO&OSED SYSTEM:

The proposed scheme takes advantage of a fact in broadcast services! many

users subscribe to multiple programs simultaneously. -n other words, programs



many programs. *ence, this study contributes to the literature a new scheme (namely

KTR to better support subscriptions of multiple programs by e/ploiting the

overlapping among programs. KTR let multiple programs share the same set of keys

for the users who subscribe to these programs.

KTR thus inherently enables 1sers to handle fewer keys and reduces the

demands of storage and processing power on resource3limited mobile devices.

econd, since multiple programs are allowed to share the same set of keys, a critical

issue is how to manage shared keys efficiently and securely. We find that when keys

need to be distributed to a user, it is unnecessary to change all of them. -n many

circumstances, when a user subscribes to new programs or un subscribes to some

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programs, a large portion of keys that the user will hold in his new subscription can be

reused without compromising security. KTR is a novel approach for determining

which keys need to be changed and for finding the minimum number of keys that

must be changed. *ence, KTR efficiently handles the rekey of the shared keys and

minimi$es the rekey costs associated with possible subscriptions. 'ur simulations

show that critical keys can be employed in logical key hierarchy schemes, to improve

their performance.

*., -EASI'ILITY STUDY:

The feasibility of the pro)ect is analy$ed in this phase and business proposal is

put forth with a very general plan for the pro)ect and some cost estimates. uring

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. +or feasibility

analysis, some understanding of the ma)or re%uirements for the system is essential.

Three key considerations involved in the feasibility analysis are

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*.7 HARD/ARE RE8UIREMENTS:

ystem ! 2entium -9 #.C :*$.

*ard isk ! CD :&.

+loppy rive ! ".CC


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*. SO-T/ARE EN)IRONMENT

(a$a Te!no%ogy

Gava technology is both a programming language and a platform.

T!e (a$a &rogra66ing Lang#age

The Gava programming language is a high3level language that can be

characteri$ed by all of the following bu$$words!

imple

Architecture neutral

'b)ect oriented

2ortable

istributed

*igh performance

-nterpreted


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6ompilation happens )ust once8 interpretation occurs each time the program is

e/ecuted. The following figure illustrates how this works.

Bou can think of Gava byte codes as the machine code instructions for the Gava 9irtual


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language is also a powerful software platform. 1sing the generous A2-, you can write

many types of programs.

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

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

network. ;/amples of servers are Web servers, pro/y servers, mail servers, and print

servers. Another speciali$ed program is a servlet. A servlet can almost be thought of

as an applet that runs on the server side. Gava ervlets are a popular choice for

building interactive web applications, replacing the use of 6:- scripts. ervlets are

similar to applets in that they are runtime e/tensions of applications. -nstead of

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

tailoring the server.

*ow does the A2- support all these kinds of programs7 -t does so with

packages of software components that provides a wide range of functionality. ;very

full implementation of the Gava platform gives you the following features!

T!e e""entia%"! 'b)ects, strings, threads, numbers, input and output, data

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

A55%et"! The set of conventions used by applets.

Net=oring! 1Rs, T62 (Transmission 6ontrol 2rotocol, 12 (1ser ata

gram 2rotocol sockets, and -2 (-nternet 2rotocol addresses.

Internationa%i>ation! *elp for writing programs that can be locali$ed for

users worldwide. 2rograms can automatically adapt to specific locales and be

displayed in the appropriate language.

Se#rity! &oth low level and high level, including electronic signatures,

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

So;t=are o65onent"! Known as Gava&eansT


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(a$a Data3a"e Conneti$ity 0(D'CTM4! 2rovides uniform access to a wide

range of relational databases.

The Gava platform also has A2-s for # and graphics, accessibility, servers,collaboration, telephony, speech, animation, and more. The following figure depicts

what is included in the Gava # K.

Ho= /i%% (a$a Te!no%ogy C!ange o#r Li;es e/tensive

feature set includes!

A consistent and well3documented A2-, supporting a wide range of chart

types8

A fle/ible design that is easy to e/tend, and targets both server3side and client3

side applications8

upport for many output types, including wing components, image files

(including 24: and G2;:, and vector graphics file formats (including 2+, ;2 and

9:8

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G+ree6hart is Popen sourceP or, more specifically, free software. -t is

distributed under the terms of the :41 esser :eneral 2ublic icense (:2, which

permits use in proprietary applications.

1. Ma5 )i"#a%i>ation"

6harts showing values that relate to geographical areas. ome e/amples

include! (a population density in each state of the 1nited tates, (b income per

capita for each country in ;urope, (c life e/pectancy in each country of the world.

The tasks in this pro)ect include!

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

states5provinces in particular countries (1A in particular, but also other areas8

6reating an appropriate dataset interface (plus default implementation, a rendered,

and integrating this with the e/isting FB2lot class in G+ree6hart8

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

*. Ti6e Serie" C!art Interati$ity

-mplement a new (to G+ree6hart feature for interactive time series charts 333 to

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

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

display in the main chart.

,. Da"!3oar2"

There is currently a lot of interest in dashboard displays. 6reate a fle/ible

dashboard mechanism that supports a subset of G+ree6hart chart types (dials,

pies, thermometers, bars, and lines5time series that can be delivered easily via

both Gava Web tart and an applet.

. &ro5erty E2itor"

The property editor mechanism in G+ree6hart only handles a small subset of the

properties that can be set for charts. ;/tend (or reimplement this mechanism to

provide greater end3user control over the appearance of the charts.

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Gava virtual machine 33 it>s )ust that they are shrunken versions of the G#; G9< and

are specific to G#


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.Con;ig#ration" o$er$ie=

The configuration defines the basic run3time environment as a set of core

classes and a specific G9< that run on specific types of devices. 6urrently, two

configurations e/ist for G#


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&ro;i%e 1: K(a$a

KGava is un>s proprietary profile and contains the KGava A2-. The KGava

profile is built on top of the 66 configuration. The KGava virtual machine, K9


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,. SYSTEM DESIGN

,.1 ARCHITECTURAL DIAGRAM:

A wireless data broadcast system consists of three components as depicted in +igure

"! (" the broadcast server8 (# the mobile devices8 and ( the communication

mechanism. The server broadcasts data on air. A user0s mobile device receives the

broadcast information, and filters the subscribed data according to user0s %ueries and

privileges. The specialty of the broadcast system is that (a the server determines the

schedule to broadcast all data on air, and (b users0 mobile devices listen to the

broadcast channel but only retrieve data (filter data out based on users0 %ueries. The

communication mechanism includes wireless broadcast channels and (optional

uplink channels. &roadcast channel is the main mechanism for data +ig. ". A wireless

data broadcast system dissemination. ata is broadcast periodically so that users can

recover lost or missed data items. The uplink channels, which have limited

bandwidth, are reserved for occasional uses to dynamically change subscriptions.-n

broadcast services, the basic data unit is 2ata ite6, such as a piece of news or a stock

price. ata items are grouped into 5rogra6" and a user specifies which programs he

would like to access. Typical programs could be weather, news, stock %uotes, etc. +or

simplicity, we assume that each program covers a set of data items, and programs are

e/clusively complete. A user may subscribe to one or more programs. The set of

subscribed programs is called the user0s "#3"ri5tion. 1sers can subscribe via-nternet or uplink channels to specify the programs that they are interested in

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receiving. 2revious studies on wireless data broadcast services have mainly focused

on performance issues such as reducing data access latency and conserving battery

power of mobile devices. 1nfortunately, the critical security re%uirements of this type

of broadcast service have not yet been addressed, i.e. broadcast service providers need

to ensure backward and forward secrecy with respect to membership dynamics. -n the

wireless broadcast environment, any user can monitor the broadcast channel and

record the broadcast data. -f the data is not encrypted, the content is open to the public

and anyone can access the data. -n addition, a user may only subscribe to a few

programs. -f data in other programs are not encrypted, the user can obtain data beyond

his subscription privilege. *ence, access control should be enforced via encrypting

data in a proper way so that only subscribing users can access the broadcast data, and

subscribing users can only access the data to which they subscribe. ymmetric3key3

based encryption is a natural choice for ensuring secure data dissemination and

access. The broadcast data can be encrypted so that only those users who own valid

keys can decrypt them. Thus, the decryption keys can be used as an effective means

for access control in wireless # data broadcast services.

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,.* CLASS DIAGRAM:

/SN a2!o No2e"

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adhoc 1

display

displayable

stream

stream1

stream2

stream3

stream4

dom

domstatus

txtmsg

txtphone

txtpassword

Shared key

Group key

startApp()

commandAction()

sendon!ess()

send message()

run()

pauseApp()

destroyApp()

encrypt()

decrypt()


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"indconnector

stream

in

out

#indonnector()

run()

Net=or Ser$er

$% Ser&er

ser&er

socket

input

output

mobilesmobileid

dominator

dominatee

connector

ser&ice()

run()

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,., USE CASE DIAGRAM:

+ig :rouping

+ig -dentification of key groups.

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'istribution Group key ndi&idual ey

Sub Grouping

ndi&idual ey

Generating eys

'istribution key

ndi&idual key

Sub Group *eaders

ndi&idual key

ndi&idual Sub Groups


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,. ACTI)ITY DIAGRAM:

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Sensor

nodes

denti"ying

Groups

ey

!anagement

ey

Generation

ey

Agreement

#ormation o" subgroup leaders

and indi&idual sub groups


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. IM&LEMENTATION

-mplementation is the stage of the pro)ect when the theoretical design is turned

out into a working system. Thus it can be considered to be the most critical stage in

achieving a successful new system and in giving the user, confidence that the new

system will work and be effective.

The implementation stage involves careful planning, investigation of the

e/isting system and it0s constraints on implementation, designing of methods to

achieve changeover and evaluation of changeover methods.

.1 MODULES:

". ogic Key *ierarchy (K* based techni%ues

#. &roadcast encryption techni%ues

. Rekey 'perations

.* LOGICAL KEY HIERARCHY:

ecure key management for wireless broadcast is closely related to secure

group key management in networking. The data encryption key (;K of the program

and each represents an individual key (-K of a user that is only shared between the

system and the user. 'ther keys in the tree, namely key distribution keys (KKs,

When a user )oins or leaves the group, the server needs to change and broadcast the

corresponding new keys, and this operation is called rekey, and the broadcast message

of new keys is called rekey message. -n our system, data and rekey messages are

broadcast in the same broadcast channel to the users.

., 'ROADCAST ENCRY&TION TECHNI8UES:

There are some other key management schemes in the literature for multicast

and broadcast services. 1sed arbitrarily revealed key se%uences to do scalable

multicast key management without any overhead on )oins5leaves. 2roposed two

schemes that insert an inde/ head into packets for decryption. *owever, both of them

re%uire pre3planned subscription, which contradicts the fact that in pervasive

computing and air data access a user may change subscriptions at any moment.

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6ompared with K*3based approaches, key management schemes in broadcast

encryption are less fle/ible regarding possible subscriptions.

. REKEY O&ERATIONS:

To issue new keys upon a user event, the main task is to identify the keys that

need to be changed. We use two types of paths in the key forest to represent the to3be3

changed keys. When a user leaves a tree, we say, a leave path is formed, which

consists of keys that the user will no longer use. When a user )oins a tree, we say, an

enroll path is formed, which consists of keys that the user will use in the future.

imilarly, when a user shifts from one tree to another, a leave path and an enroll path

are formed. -n KTR, a complete path starts from the leaf node and ends at the multiple

;Ks of the subscribed programs that share the tree. To broadcast new keys, the

server should first compose rekey packets.

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7. SYSTEM TESTING

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

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

check the functionality of components, sub assemblies, assemblies and5or a finished

product -t is the process of e/ercising software with the intent of ensuring that the

oftware system meets its re%uirements and user e/pectations and does not fail in an

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

specific testing re%uirement.

7.1 TY&ES O- TESTS

7.1.1 UNIT TESTING

1nit testing involves the design of test cases that validate that the internal

program logic is functioning properly, and that program inputs produce valid outputs.

All decision branches and internal code flow should be validated. -t is the testing of

individual software units of the application .it is done after the completion of an

individual unit before integration. This is a structural testing, that relies on knowledge

of its construction and is invasive. 1nit tests perform basic tests at component level

and test a specific business process, application, and5or system configuration. 1nit

tests ensure that each uni%ue path of a business process performs accurately to the

documented specifications and contains clearly defined inputs and e/pected results.

7.1.* INTEGRATION TESTING:

-ntegration tests are designed to test integrated software components to

determine if they actually run as one program. Testing is event driven and is more

concerned with the basic outcome of screens or fields. -ntegration tests demonstrate

that although the components were individually satisfaction, as shown by successfully

unit testing, the combination of components is correct and consistent. -ntegration

testing is specifically aimed at e/posing the problems that arise from the

combination of components.

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7.1., -UNCTIONAL TESTING:

+unctional tests provide systematic demonstrations that functions tested are

available as specified by the business and technical re%uirements, system

documentation, and user manuals.

+unctional testing is centered on the following items!

9alid -nput ! identified classes of valid input must be accepted.

-nvalid -nput ! identified classes of invalid input must be re)ected.

+unctions ! identified functions must be e/ercised.

'utput ! identified classes of application outputs must be e/ercised.

ystems52rocedures ! interfacing systems or procedures must be invoked.

'rgani$ation and preparation of functional tests is focused on re%uirements,

key functions, or special test cases. -n addition, systematic coverage pertaining to

identify &usiness process flows8 data fields, predefined processes, and successive

processes must be considered for testing. &efore functional testing is complete,

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

7.1. SYSTEM TESTING:

ystem testing ensures that the entire integrated software system meets

re%uirements. -t tests a configuration to ensure known and predictable results. An

e/ample of system testing is the configuration oriented system integration test.

ystem testing is based on process descriptions and flows, emphasi$ing pre3driven

process links and integration points.

7.1.7 /HITE 'O+ TESTING:

White &o/ Testing is a testing in which in which the software tester has

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

purpose. -t is purpose. -t is used to test areas that cannot be reached from a black bo/

level.

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7.1.9 'LACK'O+ TESTING:

&lack &o/ Testing is testing the software without any knowledge of the inner

workings, structure or language of the module being tested. &lack bo/ tests, as most

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

specification or re%uirements document, such as specification or re%uirements

document. -t is a testing in which the software under test is treated, as a black bo/

.you cannot IseeJ into it. The test provides inputs and responds to outputs without

considering how the software works.

7.* UNIT TESTING:

1nit testing is usually conducted as part of a combined code and unit test

phase of the software lifecycle, although it is not uncommon for coding and unit

testing to be conducted as two distinct phases.

Te"t "trategy an2 a55roa!

+ield testing will be performed manually and functional tests will be written in

detail.

Te"t o3?eti$e"

All field entries must work properly.

2ages must be activated from the identified link.

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

-eat#re" to 3e te"te2

9erify that the entries are of the correct format

4o duplicate entries should be allowed

All links should take the user to the correct page.

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7., INTEGRATION TESTING:

oftware integration testing is the incremental integration testing of two or

more integrated software components on a single platform to produce failures causedby interface defects.

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

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

applications at the company level U interact without error.

Te"t Re"#%t": All the test cases mentioned above passed successfully. 4o

defects encountered.

7. ACCE&TANCE TESTING:

1ser Acceptance Testing is a critical phase of any pro)ect and re%uires

significant participation by the end user. -t also ensures that the system meets the

functional re%uirements.

Te"t Re"#%t": All the test cases mentioned above passed successfully. 4o

defects encountered.

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. CONCLUSION AND -UTURE

ENHANCEMENTS

-n this work, we investigated the issues of key management in support of

secure wireless broadcast services. We proposed KTR as a scalable, efficient and

secure key management approach in the broadcast system. We used the key forest to

e/ploit the overlapping nature between users and programs in broadcast services.

KTR let multiple programs share a single tree so that the users subscribing these

programs can hold fewer keys. -n addition, we proposed a novel shared key

management approach to further reduce rekey cost by identifying the minimum set ofkeys that must be changed to ensure broadcast security.

This approach is also applicable to other K*3based approaches to reduce the

rekey cost as in KTR. 'ur simulation showed that KTR can save about C=L of

communication overhead in the broadcast channel and about =DL of decryption cost

for each user, compared with the traditional K* approach.

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II.RE-ERENCES

". G. Fu, . ee, M. *u, and W.36. ee, Iata broadcast,J in *andbook of

Wireless 4etworks and


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ktr docuMEW

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