cloud computing security from single to multi clouds

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Cloud Computing Security: From Single to Multi-Clouds Abstract: The use of cloud computing has increased rapidly in many organizations. Cloud computing provides many benefits in terms of low cost and accessibility of data. Ensuring the security of cloud computing is a major factor in the cloud computing environment, as users often store sensitive information with cloud storage providers but these providers may be untrusted. Dealing with “single cloud” providers is predicted to become less popular with customers due to risks of service availability failure and the possibility of malicious insiders in the single cloud. A movement towards “multi-clouds”, or in other words, “interclouds” or “cloud-ofclouds” has emerged recently. This paper surveys recent research related to single and multi-cloud security and addresses possible solutions. It is found that the research into the use of multicloud providers to maintain security has received less attention from the research community than has the use of single clouds. This work aims to promote the use of multi-clouds due to its ability to reduce security risks. Algorithm Used: Secret Sharing Algorithms : Data stored in the cloud can be compromised or lost. So, we have to come up with a way to secure those files. We can encrypt them

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Page 1: Cloud Computing Security From Single to Multi Clouds

Cloud Computing Security: From Single toMulti-Clouds

Abstract:

The use of cloud computing has increased rapidly in many organizations. Cloud computing

provides many benefits in terms of low cost and accessibility of data. Ensuring the security of

cloud computing is a major factor in the cloud computing environment, as users often store

sensitive information with cloud storage providers but these providers may be untrusted. Dealing

with “single cloud” providers is predicted to become less popular with customers due to risks of

service availability failure and the possibility of malicious insiders in the single cloud. A

movement towards “multi-clouds”, or in other words, “interclouds” or “cloud-ofclouds” has

emerged recently. This paper surveys recent research related to single and multi-cloud security

and addresses possible solutions. It is found that the research into the use of multicloud providers

to maintain security has received less attention from the research community than has the use of

single clouds. This work aims to promote the use of multi-clouds due to its ability to reduce

security risks.

Algorithm Used:

Secret Sharing Algorithms:

Data stored in the cloud can be compromised or lost. So, we have to come up with a way to

secure those files. We can encrypt them before storing them in the cloud, which sorts out the

disclosure aspects. However, what if the data is lost due to some catastrophe befalling the cloud

service provider? We could store it on more than one cloud service and encrypt it before we send

it off. Each of them will have the same file. What if we use an insecure, easily guessable

password to protect the 2012 45th Hawaii International Conference on System Sciences file, or

the same one to protect all files? I have often thought that secret sharing algorithms could be

employed to good effect in these circumstances instead.

Page 2: Cloud Computing Security From Single to Multi Clouds

Background

The use of cloud computing has increased rapidly in many organizations. Subashini and Kavitha

argue that small and medium companies use cloud computing services for various reasons,

including because these services provide fast access to their applications and reduce their

infrastructure costs. Cloud providers should address privacy and security issues as a matter of

high and urgent priority. Dealing with “single cloud” providers is becoming less popular with

customers due to potential problems such as service availability failure and the possibility that

there are malicious insiders in the single cloud. In recent years, there has been a move towards

“multiclouds”, “intercloud” or “cloud-of-clouds”. This paper focuses on the issues related to the

data security aspect of cloud computing. As data and information will be shared with a third

party, cloud computing users want to avoid an untrusted cloud provider. Protecting private and

important information, such as credit card details or a patient’s medical records from attackers or

malicious insiders is of critical importance. In addition, the potential for migration from a single

cloud to a multi-cloud environment is examined and research related to security issues in single

and multi-clouds in cloud computing are surveyed.

The remainder of this paper is organized as follows.

The System describes the beginning of cloud computing and its components. In addition, it

presents examples of cloud providers and the benefits of using their services. The system

discusses security risks in cloud computing. System analyses the new generation of cloud

computing, that is, multi-clouds and recent solutions to address the security of cloud computing,

as well as examining their limitations. The System presents suggestions for future work.

NIST describes cloud computing as “a model for enabling convenient, on-demand network

access to a shared pool of configurable computing resources (e.g., networks, servers, storage,

applications, and services) that can be rapidly provisioned and released with minimal

management effort or service provider interaction”.

The three key cloud delivery models are infrastructure as a service (IaaS), platform as a service

(PaaS), and software as a service (SaaS). In IaaS, the user can benefit from networking

Page 3: Cloud Computing Security From Single to Multi Clouds

infrastructure facilities, data storage and computing services. In other words, it is the delivery of

computer infrastructure as a service. An example of IaaS is the Amazon web service. In PaaS,

the user runs custom applications using the service provider’s resources. It is the delivery of a

computing platform and solution as a service. An example of PaaS is Google Apps. Running

software on the provider’s infrastructure and providing licensed applications to users to use

services is known as SaaS. An example of SaaS is the Salesforce.com CRM application. This

model represents the second layer in the cloud environment architecture.

Cloud deployment models include public, private, community, and hybrid clouds. A cloud

environment that is accessible for multi-tenants and is available to the public is called a public

cloud. A private cloud is available for a particular group, while a community cloud is modified

for a specific group of customers. Hybrid cloud infrastructure is a composition of two or more

clouds (private, community, or public cloud). This model represents the third layer in the cloud

environment architecture. Kamara and Lauter present two types of cloud infrastructure only,

namely private and public clouds. The infrastructure that is owned and managed by users is in

the private cloud. Data that is accessed and controlled by trusted users is in a safe and secure

private cloud, whereas the infrastructure that is managed and controlled by the cloud service

provider is in a public cloud. In particular, this data is out of the user’s control, and is managed

and shared with unsafe and un trusted servers.

Cloud Service Providers Examples

In the commercial world, various computing needs are provided as a service. The service

providers take care of the customer's needs by, for example, maintaining software or purchasing

expensive hardware. For instance, the service EC2, created by Amazon, provides customers with

scalable servers. As another example, under the CLuE program, NSF joined with Google and

IBM to offer academic institutions access to a large-scale distributed infrastructure. There are

many features of cloud computing. First, cloud storages, such as Amazon S3, Microsoft

SkyDrive, or NirvanixCLoudNAS, permit consumers to access online data. Second, it provides

computation resources for users such as Amazon EC2. Third, Google Apps or versioning

repositories for source code are examples of online collaboration tools. Cloud service providers

should ensure the security of their customers’ data and should be responsible if any security risk

Page 4: Cloud Computing Security From Single to Multi Clouds

affects their customers’ service infrastructure. A cloud provider offers many services that can

benefit its customers, such as fast access to their data from any location, scalability, pay-for-use,

data storage, data recovery, protection against hackers, on-demand security controls, and use of

the network and infrastructure facilities. Reliability and availability are other benefits of the

public cloud, in addition to low cost. However, there are also concerning issues for public cloud

computing, most notably, issues surrounding data integrity and data confidentiality. Any

customer will be worried about the security of sensitive information such as medical records or

financial information.

Security Risks in Cloud Computing

Although cloud service providers can offer benefits to users, security risks play a major role in

the cloud computing environment. Users of online data sharing or network facilities are aware of

the potential loss of privacy. According to a recent IDC survey , the top challenge for 74% of

CIOs in relation to cloud computing is security. Protecting private and important information

such as credit card details or patients’ medical records from attackers or malicious insiders is of

critical importance. Moving databases to a large data centre involves many security challenges

such as virtualization vulnerability, accessibility vulnerability, privacy and control issues related

to data accessed from a third party, integrity, confidentiality, and data loss or theft. Subashini and

Kavitha present some fundamental security challenges, which are data storage security,

application security, data transmission security, and security related to third-party resources.

In different cloud service models, the security responsibility between users and providers is

different. According to Amazon, their EC2 addresses security control in relation to physical,

environmental, and virtualization security, whereas, the users remain responsible for addressing

security control of the IT system including the operating systems, applications and data.

According to Tabakiet al. the way the responsibility for privacy and security in a cloud

computing environment is shared between consumers and cloud service providers differs

between delivery models. In SaaS, cloud providers are more responsible for the security and

privacy of application services than the users. This responsibility is more relevant to the public

than the private cloud environment because the clients need more strict security requirements in

the public cloud. In PaaS, users are responsible for taking care of the applications that they build

Page 5: Cloud Computing Security From Single to Multi Clouds

and run on the platform, while cloud providers are responsible for protecting one user’s

applications from others. In IaaS, users are responsible for protecting operating systems and

applications, whereas cloud providers must provide protection for the users’ data. Ristenpartet al

claim that the levels of security issues in IaaS are different. The impact of security issues in the

public cloud is greater than the impact in the private cloud. For instance, any damage which

occurs to the security of the physical infrastructure or any failure in relation to the management

of the security of the infrastructure will cause many problems. In the cloud environment, the

physical infrastructure that is responsible for data processing and data storage can be affected by

a security risk.

Data Integrity

One of the most important issues related to cloud security risks is data integrity. The data stored

in the cloud may suffer from damage during transition operations from or to the cloud storage

provider. Cachinet give examples of the risk of attacks from both inside and outside the cloud

provider, such as the recently attacked Red Hat Linux’s distribution servers. Another example of

breached data occurred in 2009 in Google Docs, which triggered the Electronic Privacy

Information Centre for the Federal Trade Commission to open an investigation into Google’s

Cloud Computing Services. Another example of a risk to data integrity recently occurred in

Amazon S3 where users suffered from data corruption. Cachinet system argue that when

multiple clients use cloud storage or when multiple devices are synchronized by one user, it is

difficult to address the data corruption issue. One of the solutions that they propose is to use a

Byzantine fault-tolerant replication protocol within the cloud. Hendricks et al. state that this

solution can avoid data corruption caused by some components in the cloud. However, Cachinet

al. claim that using the Byzantine fault tolerant replication protocol within the cloud is unsuitable

due to the fact that the servers belonging to cloud providers use the same system installations and

are physically located in the same place.

Page 6: Cloud Computing Security From Single to Multi Clouds

Literature Survey:

1. SPORC: Group Collaboration using Untrusted Cloud Resources

Cloud-based services are an attractive deployment model for user-facing applications like word

processing and calendaring. Unlike desktop applications, cloud services allow multiple users to

edit shared state concurrently and in real-time, while being scalable, highly available, and

globally accessible. Unfortunately, these benefits come at the cost of fully trusting cloud

providers with potentially sensitive and important data. To overcome this strict tradeoff, we

present SPORC, a generic framework for building a wide variety of collaborative applications

with untrusted servers. In SPORC, a server observes only encrypted data and cannot deviate

from correct execution without being detected. SPORC allows concurrent, low-latency editing of

shared state, permits disconnected operation, and supports dynamic access control even in the

presence of concurrency. We demonstrate SPORC’s flexibility through two prototype

applications: a causally-consistent key-value store and a browser-based collaborative text editor.

Conceptually, SPORC illustrates the complementary benefits of operational transformation (OT)

and fork* consistency. The former allows SPORC clients to execute concurrent operations

without locking and to resolve any resulting conflicts automatically. The latter prevents a

misbehaving server from equivocating about the order of operations unless it is willing to fork

clients into disjoint sets. Notably, unlike previous systems, SPORC can automatically recover

from such malicious forks by leveraging OT’s conflict resolution mechanism.

Disadvantages

1. The data integrity is proving only based on the filename and not on the file blocks or

any other public key.

2. The attackers details are not dynamic instead its maintaining the log files to store the

attacker details and viewing using data mining concepts which is time consuming job and

less security.

Page 7: Cloud Computing Security From Single to Multi Clouds

2. Authentication and Integrity in Outsourced Databases

In the Outsourced Database (ODB) model, entities outsource their data management needs to

third-party service providers. Such a service provider offers mechanisms for its clients to create,

store, update and access (query) their databases. This work provides mechanisms to ensure data

integrity and authenticity for outsourced databases. Specifically, this work provides mechanisms

that assure the querier that the query results have not been tampered with and are authentic (with

respect to the actual data owner). It investigates both security and efficiency aspects of the

problem and constructs several secure and practical schemes that facilitate integrity and

authenticity of query replies while incurring low computational and communication costs.

Disadvantages

1. There is no feature of automatic blocking the cloud server attackers.

2. Owner data will be stored in un trusted cloud servers.

Page 8: Cloud Computing Security From Single to Multi Clouds

3. Ensuring Data Storage Security in Cloud Computing

Cloud Computing has been envisioned as the next generation architecture of IT Enterprise. In

contrast to traditional solutions, where the IT services are under proper physical, logical and

personnel controls, Cloud Computing moves the application software and databases to the large

data centers, where the management of the data and services may not be fully trustworthy. This

unique attribute, however, poses many new security challenges which have not been well

understood. In this article, we focus on cloud data storage security, which has always been an

important aspect of quality of service. To ensure the correctness of users’ data in the cloud, we

propose an effective and flexible distributed scheme with two salient features, opposing to its

predecessors. By utilizing the homomorphic token with distributed verification of erasure-coded

data, our scheme achieves the integration of storage correctness insurance and data error

localization, i.e., the identification of misbehaving server(s). Unlike most prior works, the new

scheme further supports secure and efficient dynamic operations on data blocks, including: data

update, delete and append. Extensive security and performance analysis shows that the proposed

scheme is highly efficient and resilient against Byzantine failure, malicious data modification

attack, and even server colluding attacks.

Disadvantages

1. There is no feature of automatic blocking the cloud server attackers.

2. Less Security – No cryptographic technique is used on the cloud data

Page 9: Cloud Computing Security From Single to Multi Clouds

System Architecture

Existing System:

Cloud providers should address privacy and security issues as a matter of high and urgent

priority. Dealing with “single cloud” providers is becoming less popular with customers due to

potential problems such as service availability failure and the possibility that there are malicious

insiders in the single cloud. In recent years, there has been a move towards “multiclouds”,

“intercloud” or “cloud-of-clouds”.

Disadvantages:

1. Cloud providers should address privacy and security issues as a matter of high and urgent

priority.

Page 10: Cloud Computing Security From Single to Multi Clouds

2. Dealing with “single cloud” providers is becoming less popular with customers due to

potential problems such as service availability failure and the possibility that there are malicious

insiders in the single cloud.

Proposed System:

This paper focuses on the issues related to the data security aspect of cloud computing. As data

and information will be shared with a third party, cloud computing users want to avoid an un

trusted cloud provider. Protecting private and important information, such as credit card details

or a patient’s medical records from attackers or malicious insiders is of critical importance. In

addition, the potential for migration from a single cloud to a multi-cloud environment is

examined and research related to security issues in single and multi-clouds in cloud computing

are surveyed.

Advantages:

1. Data Integrity

2. Service Availability.

3. The user runs custom applications using the service provider’s resources

4. Cloud service providers should ensure the security of their customers’ data and should be

responsible if any security risk affects their customers’ service infrastructure.

Page 11: Cloud Computing Security From Single to Multi Clouds

SYSTEM REQUIREMENT:

This Chapter describes about the requirements. It specifies the hardware and software

requirements that are required in order to run the application properly. The Software

Requirement Specification (SRS) is explained in detail, which includes overview of this

dissertation as well as the functional and non-functional requirement of this dissertation.

SRS for Single To Multi Cloud

Functional Control the file access at cloud server, Data Integrity Proof

at TPA. File Privacy Management

Non- Functional Cloud servers never monitors and controls the TPA

External interface LAN , Routers

Performance Finding File Hacker Information, File Sharing efficiency

fairness

Attributes File Management,tpa,cloud server,owner,Remote Users,

Blocked Users,Multi Cloud

Table: 3.1 Summaries of SRS

Functional Requirements

Functional Requirement defines a function of a software system and how the system must

behave when presented with specific inputs or conditions. These may include calculations, data

manipulation and processing and other specific functionality. In this system following are the

functional requirements:-

The Owner will divide the file into ‘N’ number of blocks and has to upload the each block the

individual cloud servers.

Page 12: Cloud Computing Security From Single to Multi Clouds

The Cloud server has to authorize the valid remote users. if the Remote user is hacker then he

has to block in the cloud server. The data should be integrated by the cloud server.

The Third party auditor has to maintain the error localization and has to monitor the Cloud

Server Activities.

The Remote user has to user correct Secret key and file name. If anyone is wrong then he is

detected as attacker.

The Attributes are File Management, tpa, cloud server, owner, Remote user and blocked user.

Non – Functional Requirements

Non – Functional requirements, as the name suggests, are those requirements that are not

directly concerned with the specific functions delivered by the system. They may relate to

emergent system properties such as reliability response time and store occupancy. Alternatively,

they may define constraints on the system such as the capability of the Input Output devices and

the data representations used in system interfaces. Many non-functional requirements relate to

the system as whole rather than to individual system features. This means they are often critical

than the individual functional requirements. The following non-functional requirements are

worthy of attention.

The key non-functional requirements are:

Security: The system should allow a secured communication between Cs and

TPA, User and File Owner

Energy Efficiency: The Energy consumed by the Users to receive the File information

from the cloud server

Reliability: The system should be reliable and must not degrade the performance of the

existing system and should not lead to the hanging of the system.

Page 13: Cloud Computing Security From Single to Multi Clouds

Performance

The network performance can be determined by few terms such as the cloud busy time, File

utilization level, efficiency, fairness and imbalance. The amount of the time the cs allocated for

File transmission and reception is called cs busy time. Similarly channel is sometimes being idle

during communication. The unit of time which makes delay to transmit a packet is called channel

access delay time. The channel or medium utilization level can be defined as average rate of

reliable packets delivered through the channel. The MAC layer utilization level can be

determined by noticing whether the medium is busy or idle. The binary values are used for

indicating MAC layer utilization level. 1,0 are used for indicating channel is now busy or idle

respectively.

The main factor deciding buffer overflow is interface queue length when the queue length is

limited in the network. The main terms that are to be calculated to determine the network

performance are efficiency, fairness and imbalance.

The efficiency of the communication is calculated by number hops the successful packets

travelled to the total number of packets placed (dropped and retransmitted also included) in the

Network.

Page 14: Cloud Computing Security From Single to Multi Clouds

Problem Definition

The problem of the system incorporates the previous system advantages and extends to find the

unauthorized user, to prevent the unauthorized data access for preserving data integrity. The

proposed system monitors the user requests according the user specified parameters and it checks

the parameters for the new and existing users.

The system accepts existing validated user, and prompts for the new users for the parameter to

match requirement specified during user creation for new users. If the new user prompts

parameter matches with cloud server, it gives privileges to access the Audit protocol author wise

the system automatically blocks the Audit protocol for specific user.

Objective

The Objective of the system is to Block the attackers in cloud servers automatically using

automatic protocol, computing the cloud securely, secret sharing with Byzantine failure and

proving the data integrity and batch auditing by the data owners.

Page 15: Cloud Computing Security From Single to Multi Clouds

Module Description:

1. Data Integrity

2. Data Intrusion

3. Service Availability

4. Dep SKy System Model

Data Integrity:

One of the most important issues related to cloud security risks is data integrity. The data stored

in the cloud may suffer from damage during transition operations from or to the cloud storage

provider. Cachinet al. give examples of the risk of attacks from both inside and outside the cloud

provider, such as the recently attacked Red Hat Linux’s distribution servers. One of the solutions

that they propose is to use a Byzantine fault-tolerant replication protocol within the cloud.

Hendricks et al. State that this solution can avoid data corruption caused by some components in

the cloud. However, Cachinet al.Claim that using the Byzantine faulttolerant replication protocol

within the cloud is unsuitable due to the fact that the servers belonging to cloud providers use the

same system installations and are physically located in the same place.

Data Intrusion:

According to Garfinkel, another security risk that may occur with a cloud provider, such as the

Amazon cloud service, is a hacked password or data intrusion. If someone gains access to an

Amazon account password, they will be able to access all of the account’s instances and

resources. Thus the stolen password allows the hacker to erase all the information inside any

virtual machine instance for the stolen user account, modify it, or even disable its services.

Furthermore, there is a possibility for the user’s email(Amazon user name) to be hacked (see for

a discussion of the potential risks of email), and since Amazon allows a lost password to be reset

by email, the hacker may still be able to log in to the account after receiving the new reset

password.

Page 16: Cloud Computing Security From Single to Multi Clouds

Service Availability:

Another major concern in cloud services is service availability. Amazon mentions in its licensing

agreement that it is possible that the service might be unavailable from time to time. The user’s

web service may terminate for any reason at any time if any user’s files break the cloud storage

policy. In addition, if any damage occurs to any Amazon web service and the service fails, in this

case there will be no charge to the Amazon Company for this failure. Companies seeking to

protect services from such failure need measures such as backups or use of multiple providers.

DepSKy System Model:

The DepSky system model contains three parts: readers, writers, and four cloud storage

providers, where readers and writers are the client’s tasks. Bessani et al. explain the difference

between readers and writers for cloud storage. Readers can fail arbitrarily (for example, they can

fail by crashing, they can fail from time to time and then display any behavior) whereas, writers

only fail by crashing.

Cryptography Techniques

Implementing Elliptic curve cryptography for encrypting and decrypting the owner data.

Page 17: Cloud Computing Security From Single to Multi Clouds

System Configuration:-

H/W System Configuration:-

Processor - Pentium –III

Speed - 1.1 Ghz

RAM - 256 MB(min)

Hard Disk - 20 GB

Floppy Drive - 1.44 MB

Key Board - Standard Windows Keyboard

Mouse - Two or Three Button Mouse

Monitor – SVGA

S/W System Configuration:-

Operating System : Windows95/98/2000/XP

Application Server : Tomcat5.0/6.X

Front End : Java (AWT,Swing,RMI,Networking)

Scripts : JavaScript.

Database Connectivity : Mysql.

Page 18: Cloud Computing Security From Single to Multi Clouds

Future Enhancement #1 Generating Alerts On Mobile Devices

Using MaxAccu Cloak Algorithm

In location-based services, users with location-aware mobile devices are able to

make queries about their surroundings anywhere and at any time. While this ubiquitous

computing paradigm brings great convenience for information access, it also raises concerns

over potential intrusion into user location privacy. To protect location privacy, one typical

approach is to cloak user locations into spatial regions based on user-specified privacy

requirements, and to transform location-based queries into region-based queries. In this paper,

we identify and address three new issues concerning this location cloaking approach. First, we

study the representation of cloaking regions and show that a circular region generally leads to a

small result size for region based queries.

Second, we develop a mobility-aware location cloaking technique to resist trace

analysis attacks. Two cloaking algorithms, namely MaxAccu Cloak and MinComm Cloak , are

designed based on different performance objectives. Finally, we develop an efficient polynomial

algorithm for evaluating circularregion- based kNN queries. Two query processing modes,

namely bulk and progressive, are presented to return query results either all at once or in an

incremental manner. Experimental results show that our proposed mobility-aware cloaking

algorithms significantly improve the quality of location cloaking in terms of an entropy measure

without compromising much on query latency or communication cost. Moreover, the progressive

query processing mode achieves a shorter response time than the bulk mode by parallelizing the

query evaluation and result transmission.

Page 19: Cloud Computing Security From Single to Multi Clouds

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