storage management in private cloud

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An Implementation of Storage Management inPrivate Cloud

PROJECT REPORT

Submitted in partial ful f i llment for the award of the degree of

MS

I n

Software Engineering

By

MKS SRI HARISH 10mse0116

VENGAT SUDHEENDRA 10mse0337

Under the Guidance of

PROF M LAWANYA SHRI

VITU N I V E R S I T Y

(Estd. u/s 3 of UGC Act 1956)

School of Information Technology & Engineering [SITE]

SOFTWARE ENGINEERING DIVISION

NOV 2013


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DECLARATION BY THE CANDIDATE

We hereby declare that the project report entitled An Implementation of

Storage Management in Private Cloud submitted by us to Vellore

Institute of Technology, Vellore in partial fulfillment of the requirement for

the award of the degree of M.S.(Software Engineering) is a record of

bonafide project work carried out by us under the guidance of Prof. M

LAWANYA SHRI. We further declare that the work reported in this

project has not been submitted and will not be submitted, either in part or in

full, for the award of any other degree or diploma in this institute or any

other institute or university.

Place: VelloreDate:

Signature of the Candidates

M.K.S.SRIHARISH, 10mse0116

VENGAT SUDHEENDRA, 10mse0337


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VITU N I V E R S I T Y

(Estd. u/s 3 of UGC Act 1956)

School of Information Technology & Engineering [SITE]

SOFTWARE ENGINEERING DIVISION

CERTIFICATE

This is to certify that the project report entitled An Implementation of

Storage Management in Private Cloud submitted by MKS SRI

HARISH (10mse0116) and VENGAT SUDHEENDRA (10mse0337) toVellore Institute of Technology, Vellore in partial fulfillment of the

requirement for the award of the degree of M.S.(Software Engineering)is

a record of bonafide work carried out by him/her under my guidance. The

project fulfills the requirements as per the regulations of this Institute and in

my opinion meets the necessary standards for submission. The contents of

this report have not been submitted and will not be submitted either in part

or in full, for the award of any other degree or diploma in this institute or

any other institute or university.

Prof. M LAWANYA SHRI

GUIDE

ASST.PROF, SITE

Internal Examiner (s) External Examiner (s)


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CERTIFICATE BY THE EXTERNAL GUIDE

This is to certify that the project report entitled Implementation of

storage management using private cloud submitted by MKS Sriharish(10mse0116) and Vengat Sudheendra(10mse0337) to VelloreInstitute of Technology University, Vellore in partial fulfillment ofthe requirement for the award of the degree MS in SoftwareEngineering is a record of bonafide work carried out by him/her undermy guidance. The project fulfills the requirements as per theregulations of this Institute and in my opinion meets the necessarystandards for submission. The contents of this report have not been

submitted and will not be submitted either in part or in full, for theaward of any other degree or diploma in this institute or any otherinstitute or university.

EXTERNAL SUPERVISOR


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ACKNOWLEDGEMENT

We would like to thank the chancellor of Vellore Institute of Technology

University, Dr. G. Viswanathan,for giving us the opportunity to pursue M.S Software

Engineering.

We would like to thank the Director of School of Information Technology and

Engineering Dr. R.Saravanan.

We would also like to thank our Program Manager of M.S Software Engineering,

Prof Jayaram Reddyfor giving us adequate guidance to carry out our project.

We would also like to thank our year coordinator of M.S Software Engineering,

Prof Manikandanfor giving us adequate support and guidance to carry out our project.

We would like to extend our sincere thanks to Prof. M Lawanya Shri our

internal guide for her timely help and support and for guiding us to complete the project

successfully.

Place : Vellore

Date :M.K.S. SRIHARISH

VENGAT SUDHEENDRA


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Table of Contents

Chapter No Title Page No

ABSTRACT i

LIST OF TABLES iii

LIST OF FIGURES Iv

LIST OF SYMBOLS v

1. INTRODUCTION 1

1.1 OVERVIEW 1

1.2 PURPOSE 2

1.3 SCOPE 2

1.4 OBJECTIVE 2

2. PROBLEM ANALYSIS 3

2.1 ABSTRACT 3

2.2 DEFINITION OF CONCEPTS 42.3 LITERATURE REVIEW 8

3 DESIGN AND ARCHITECTURE 14

3.1 EUCALYPTUS ARCHITECTURE 14

3.2 CLASS DIAGRAM 16

3.3 USE CASE DIAGRAM 17

3.4 ACTIVITY DIAGRAM 18

3.5 SEQUENCE DIAGRAM 19

3.6 EXPERIMENT SET UP 20

4 IMPLEMENTATION 30

4.1 METHODOLOGY USED 30

4.2 IMPLEMENTATION OF THE SYSTEM 314.3 TESTING 41

5 CONCLUSION AND FUTURE WORK 50

5.1 CONCLUSION 50

5.2 FUTURE WORK 51

6 REFERENCES 52


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i

Abstract

Private cloudis the phrase used to describe a cloud computing

platform that is implemented within the corporate firewall, under thecontrol of the IT department. Organizations in every industry, regardlessof size or geography are embracing cloud computing as a way to reducethe complexity and costs associated with traditional IT approaches. Thereality is driven by three related shifts. Customer, employee and partnerexpectations are changing as self- service consumption of technologyand services becomes the norm. The economics of computing arechanging as organizations access world-class computing power, nowavailable anytime, anywhere. Faster delivery of higher-value productsand services is now mandatory to address formidable competition and

escalating customer and shareholder expectations. Storage managementis a general storage industry phrase that is used to describe the tools,

processes, and policies used to manage storage networks and storageservices such as virtualization, replication, mirroring, security,compression, traffic analysis and other services. The phrase storagemanagement also encompasses numerous storage technologies including

process automation, real-time infrastructure products and storageprovisioning. Private cloud also called internal cloud is cloudinfrastructure operated solely for a single organization, whether managed

internally or by a third-party and hosted internally or externally. Aprivate cloud is designed to offer the same features and benefits of publiccloud systems, but removes a number of objections to the cloudcomputing model including control over enterprise and customer data,worries about security, and issues connected to regulatory compliance.Some of the advantages of cloud storage are: a cloud storage serviceautomatically transfers files into the cloud; access to unlimited cloudstorage services; ability to synchronize files across different computers;very easy to share files with others. The proposed model is to build a

private cloud in our infrastructure using eucalyptus software platformand provide database (include - storage) as a service to the user. Cloudcomputing is the use of a networked resources that are on demand whichcan be either Server, application, storage, services through a pool ofshared devices that are interconnected to a remote device that offers it.Private cloud is a solution that has been recently developed for theaccess of shared resources solely for a single entity or organizationwhere the sharing is managed either internally or externally through athird party client. Private cloud has had its inception to incorporate the

aspects of enhanced security features to a private organizations data andservices. The foundation for cloud is the systematic virtualization of


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resources that further proceeded towards the out of box thinking of aprivate cloud where each and every organizations resources arevirtualized and shared. The reason for preference of private cloud is thegreater control of the entire stack of resources available. The issue of

storage management in private cloud arises when there is an extensivedemand for resources. In this project, we have implemented an effectivestorage management mechanism for uploading and sharing of files on astorage cloud. This is done by removing the need to transfer files

between users (when files are shared) and to simply grant them privilegeto access those files by using database entries. This not only helps tomanage memory but also to increase security in the cloud server.


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LIST OF TABLES

S.NO Table Name Page No

1 Table 2.1 Front End Requirements 6

2 Table 2.2 Node Requirements 7

3 Table 2.3 Literature Review 8

4 4.3.1 UTC 1 - Test whether the website can be accessedwithin the cluster.

41

5 4.3.2 UTC 2Test whether the user is able to register. 42

6 4.3.3 UTC 3Test whether the user is able to upload files. 43

7 4.3.4 UTC 4Test whether another user is able to accessuploaded files.

44

8 4.3.5 UTC 5Test whether the user is able to download files. 46

9 4.3.6 UTC 6Test whether the user is able to share theupload files.

47

10 4.3.7 UTC 7Test whether the user is able to delete theuploaded file(s).

49


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LIST OF FIGURES

S.NO Figure Name Page No

1 Fig 3.1 Eucalyptus Architecture 14

2 Fig 3.2 Project System Architecture 14

3 Fig 3.3 Class Diagram 16

4 Fig 3.4 Use Case Diagram 17

5 Fig 3.5 Activity Diagram 18

6 Fig 3.6 Sequence Diagram 19

7 Fig 3.7 Install Screen 20

8 Fig 3.8 Install Screen 2 21

9 Fig 3.9 Install Screen 3 21

10 Fig 3.10 UEC store 24

11 Fig 3.11 UEC Images 25

12 Fig 4.1 Waterfall model 30

13 Fig 4.2 Home Page 31

14 Fig 4.3 Sign up Page 32

15 Fig 4.4 Log in Page 33

16 Fig 4.5 Upload Page 34

17 Fig 4.6 File Successfully Uploaded 35

18 Fig 4.7 Confirm Replace Page 35

19 Fig 4.9 File Index 36

20 Fig 4.10 File Access 37

21 Fig 4.11 File Download 38

22 Fig 4.12 File Share 39

23 Fig 4.13 Shared File 39

24 Fig 4.14 Confirm Deletion 40

25 Fig 4.15 File Deleted 40

26 Fig 4.16 File Uploaded 44

27 Fig 4.17 File Index view 45

28 Fig 4.18 File Share Test 48

29 Fig 4.19 File Share Test 48


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LIST OF ACRONYMS

Node Controller (NC)- Eucalyptus component that runs on nodes which host the virtualmachines that comprise the cloud. This service is provided by the Ubuntu package eucalyptus-nc.

S3- Simple Storage Service. Amazon's pay-by-the-gigabyte persistent storage solution for EC2.

Storage Controller (SC)- Eucalyptus component that manages dynamic block storage services(EBS). Each 'cluster' in a Eucalyptus installation can have its own Storage Controller. This

component is provided by the eucalyptus-scpackage.

UEC- Ubuntu Enterprise Cloud. Ubuntu's cloud computing solution, based on Eucalyptus.

VM- Virtual Machine.

VT- Virtualization Technology. An optional feature of some modern CPUs, allowing for

accelerated virtual machine hosting.

Walrus- Eucalyptus component that implements the Amazon S3 API, used for storing VMimages and user storage using S3 bucket put/get abstractions.


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Chapter 1

INTRODUCTION

1.1 Overview

Cloud computingis an expression used to describe a variety of computing concepts

that involve a large number of computers connected through a real-time

communication network such as the Internet In science, cloud computing is a

synonym for distributed computing over a network, and means the ability to run a

program or application on many connected computers at the same time. The phrase

also more commonly refers to network-based services, which appear to be provided

by real server hardware, and are in fact served up by virtual hardware, simulated by

software running on one or more real machines. Such virtual servers do not

physically exist and can therefore be moved around and scaled up (or down) on thefly without affecting the end user - arguably, rather like a cloud.

The popularity of the term can be attributed to its use in marketing to sell hosted

services in the sense of application service provisioning that run client server

software on a remote location.

Cloud computing is a kind of grid computing, it has evolved by addressing

the QoS (quality of service) and reliability problems. Cloud computing provides thetools and technologies to build data/compute intensive parallel applications with

much more affordable prices compared to traditional parallel computing techniques.

Private cloud is cloud infrastructure operated solely for a single organization,

whether managed internally or by a third-party and hosted internally or

externally. Undertaking a private cloud project requires a significant level and degree

of engagement to virtualize the business environment, and requires the organization

to re-evaluate decisions about existing resources. When done right, it can improve

business, but every step in the project raises security issues that must be addressed to

prevent serious vulnerabilities. They have attracted criticism because users "still haveto buy, build, and manage them" and thus do not benefit from less hands-on

management, essentially "the economic model that makes cloud computing such an

intriguing concept".


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1.2 Purpose

The purpose of this project is to implement the storage management mechanism in avirtual environment in a way to enhance the abilities and capabilities of the cloudsystem. The ultimate purpose is to depict the endurance power of the cloud storage

system.

1.3 Scope

The scope of this process is not just limited to cloud storage system but also itsworking in different environments where it has been deployed. The cloud storagemechanism along with its shadow the virtual environment is combined in a

privately created cloud wherein the interaction are not just limited within the cloudnetwork but also to all the networks interconnected through its IP address.

1.4 Objective

Implement a private cloud and its deployment.

Implement a virtual environment and its interconnections

Implement a workable storage mechanism in the virtual environment

Ensure maintainability of the implemented storage mechanism


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CHAPTER 2

PROBLEM ANALYSIS

2.1 Problem Overview

Organizations in every industry, regardless of size or geography are embracing cloudcomputing as a way to reduce the complexity and costs associated with traditional ITapproaches. The reality is driven by three related shifts. Customer, employee and

partner expectations are changing as self- service consumption of technology andservices becomes the norm. The economics of computing are changing asorganizations access world-class computing power, now available anytime,anywhere. Faster delivery of higher-value products and services is now mandatory toaddress formidable competition and escalating customer and shareholder

expectations.

Storage managementis a general storage industry phrase that is used to describe thetools, processes, and policies used to manage storage networks and storage servicessuch as virtualization, replication, mirroring, security, compression, traffic analysisand other services. The phrase storage management also encompasses numerousstorage technologies including process automation, real-time infrastructure productsand storage provisioning.

Private cloud also called internal cloud is cloud infrastructure operated solely for asingle organization, whether managed internally or by a third-party and hostedinternally or externally. A private cloud is designed to offer the same features and

benefits of public cloud systems, but removes a number of objections to the cloudcomputing model including control over enterprise and customer data, worries aboutsecurity, and issues connected to regulatory compliance.

Some of the advantages of cloud storage are: a cloud storage service automaticallytransfers files into the cloud; access to unlimited cloud storage services; ability tosynchronize files across different computers; very easy to share files with others.

The proposed model is to build a private cloud in our infrastructure using eucalyptus

software platform and provide database (include - storage) as a service to the userusing UEC.


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2.2 Definition of Concepts

Storage as Service

Virtualization

Eucalyptus software

UEC

2.2.1 Storage as Service

Storage as a service is an architecture model in which a provider provides digitalstorage on their own infrastructure. Storage as a service can be implemented as a

business model in which a large service provider rents space in their storage

infrastructure on a subscription basis. The economy of scale in the service provider's

infrastructure theoretically allows them to provide storage much more cost

effectively than most individuals or corporations can provide their own storage,

when total cost is considered is considered. Storage as a Service is often used to

solve offsite backup challenges.

2.2.2 Virtualization

Storage virtualization is part of the software-defined storage layer that must offerimprovements in performance and space efficiency without requiring the purchase ofadditional storage hardware.It must enable rapid provisioning so that high-performance, space-efficient storagecan be spun up as fast as a VM can be spun up today. It must offer a VM-centricstorage management model that is intuitive for virtual administrators who are takingon more of the storage management tasks in virtual environments. And it mustintegrate with the hypervisor platform to leverage familiar, native workflows.Storage virtualization is a combination of capabilities that provide an abstractionlayer for physical storage resources to be addressed, managed and optimized in a

virtualization deployment.Storage virtualization technology provides a fundamentally better way to managestorage resources for virtual infrastructure, giving the ability to:

Significantly improve storage resource utilization and flexibility Simplify OS patching and driver requirements, regardless of storage topology Increase application uptime and simplify day-to-day operations Leverage and complement existing storage infrastructure

2.2.3 Eucalyptus

Eucalyptus is free and open-source computer software for building Amazon WebService (AWS)-compatible private and hybrid cloud computing environmentsmarketed by the company Eucalyptus Systems. Eucalyptus enables pooling compute,


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storage, and network resources that can be dynamically scaled up or down asapplication workloads change.Eucalyptus has six components:

The Cloud Controller (CLC)is aJavaprogram that offers EC2-compatible

interfaces, as well as a web interface to the outside world. In addition to handlingincoming requests, the CLC acts as the administrative interface for cloud

management and performs high-level resource scheduling and system

accounting. The CLC accepts user API requests from command-line interfaces

like euca2ools or GUI-based tools like the Eucalyptus User Console and

manages the underlying compute, storage, and network resources. Only one CLC

can exist per cloud and it handles authentication, accounting, reporting, and

quote management.

Walrus, also written in Java, is the Eucalyptus equivalent to AWS Simple

Storage Service (S3). Walrus offers persistent storage to all of the virtualmachines in the Eucalyptus cloud and can be used as a simple HTTP

put/getstorage as a service solution. There are no data type restrictions for

Walrus, and it can contain images (i.e., the building blocks used to launch virtual

machines), volume snapshots (i.e., point-in-time copies), and application data.

Only one Walrus can exist per cloud.

The Cluster Controller (CC)is written in C and acts as the front end for a cluster

within a Eucalyptus cloud and communicates with the Storage Controller and

Node Controller. It manages instance (i.e., virtual machines) execution and

Service Level Agreements (SLAs) per cluster.

The Storage Controller (SC) is written in Java and is the Eucalyptus equivalent

to AWS EBS. It communicates with the Cluster Controller and Node Controller

and manages Eucalyptus block volumes and snapshots to the instances within its

specific cluster. If an instance requires writing persistent data to memory outside

of the cluster, it would need to write to Walrus, which is available to any instance

in any cluster.

The VMware Brokeris an optional component that provides an AWS-compatible

interface forVMware environments and physically runs on the Cluster

Controller. The VMware Broker overlays existing ESX/ESXi hosts andtransforms Eucalyptus Machine Images (EMIs) to VMware virtual disks. The

VMware Broker mediates interactions between the Cluster Controller and

VMware and can connect directly to either ESX/ESXi hosts or to vCenter Server.

TheNode Controller (NC)

2.2.4 UEC

Prerequisites

To deploy a minimal cloud infrastructure, youll need at

least twodedicated systems: A front end.
http://en.wikipedia.org/wiki/Java_(programming_language)http://en.wikipedia.org/wiki/Storage_as_a_servicehttp://en.wikipedia.org/wiki/VMwarehttp://en.wikipedia.org/wiki/VMwarehttp://en.wikipedia.org/wiki/Storage_as_a_servicehttp://en.wikipedia.org/wiki/Java_(programming_language)


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One or more node(s).

The following are recommendations, rather than fixed requirements.However, our experience in developing this documentation indicated the

following suggestions.Front End Requir ements

Use the following table for a system that will run one or more of: Cloud Controller (CLC)

Cluster Controller (CC)

Walrus (the S3-like storage service)

Storage Controller (SC)

Eucalyptus- Elastic Utility Computing Architecture for Linking Your Programs ToUseful Systems. An open source project originally from the University of Californiaat Santa Barbara, now supported by Eucalyptus Systems, a Canonical Partner.

Front-end - Physical machine hosting one (or more) of the high level Eucalyptus

components (cloud, walrus, storage controller, cluster controller).

Node - A node is a physical machine that's capable of running virtual machines,running a node controller. Within Ubuntu, this generally means that the CPU hasVT extensions, and can run the KVM hypervisor.

Table 2.1 Front End Requirements


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Node Requirements:

Table 2.2 Node Requirements


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2.3 Literature Review:

Storage

Management in

Virtualized

Cloud Environment

Sankaran Sivathanu, Ling Liu, MeiYiduo, and Xing Pu

In order to enable & support cloud-based applications in a cost-effective

manner and to lower the barrier to entryfor such applications, a somewhat recent

business model that has emerged is thatof a service provider hosting third-partyapplications in a shared data centre.A key technology that enables suchcost-efficient resource sharing in suchdata centers is virtualization; by

providing isolation and separateprotection domains for multiple thirdparty applications, virtual machines

enable server consolidation, andconsequently significant savings in thecost of managing such data centres.A detailed experimental analysis of theI/O performance observed in avirtualized environmentthrough a series of systematicexperiments on the Xen VMM platformshow that the storage I/O performanceobserved by an application inside a VMdepends on various aspects such aswhich disk partition the virtual machineuses, the CPU utilization of other VMson that system, the nature of I/O

performed by other VMs on the hostedsystem and the block size used for

performing disk I/OAs the disk seek distance is vastlyreduced when the virtual disk size issmall, the throughput achieved by a4GB virtual disk is significantly better

than that of a 40GB disk for the exactlysame workload. When disproportionateamount of disk space, with respect todata footprint of the workload, isallocated for a user, some file systemallocation policies or applicationdecisions might lead to data beingspread across a larger footprint on disk.Cloud service providers can improvetheir storage efficiency by practicingthin provisioning of their storage

resources. Customers of cloud storagecan purchase storage based on their


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expected workload footprint rather thanjust the price. This is important because,customers may tend to purchase moredisk space than what they need,especially when the price differential is

not significant. It is beneficial to placesequentially accessed virtual disk in theouter zone of the disk to achieve better

performance (Eg. VMs that host movies,large OS distributions, etc.,). When acloud service provider needs to placemultiple virtual disks in a single

physical storage, those virtual diskswhoseMost of the infrastructure cloud systemsemploy Dynamic Frequency Scaling

technique to conserve power. Therefore,strategies for co-locating workloads can

be critical for achieving maximumperformance and at the same timeconserving power. Cloud service

providers should avoid co-locating VMswith two sequential I/O workloads on asingle physical machine, even wheneach of them goes to separate physicaldisks.Virtualization overhead is more felt insequential workloads accessed throughsmaller block sizes than randomworkloads. The cloud customers canestimate the expected performance

based on the characteristics of theworkload they deploy. Cloud service

providers can practice static partitioningof memory across multiple VMs hostedin a single physical machine, wheneverstrict performance isolation is important

across different customers.

Secure Data storage

and Retr ieval in the

Cloud

Vaibhav Khadilkar, Anuj Gupta,Murat Kantarcioglu, Latifur Khan,

Bhavani Thuraisingham

A new web-based system is created(Hive Access System) that minimizesstorage costs and provides sufficientlevel of security in cloud.

The Hadoop Distributed File System iscombined with Hive to provide acommon storage area for participatingorganizations.

The System has a mechanism to load


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and query shared data securely that isstored in HDFS using Hive.

It also has an additional layer of securityabove HDFS and Hive using a XACML

policy-based mechanism.

The system provides a secure loginfeature to users based on a salted hashtechnique. When a user logs into oursystem, based on the group that the user

belongs to he/she is provided withdifferent options.

The system also allows new users toregister but only a designated special

user admin can assign these users tothe appropriate groups.

The System is provided with some basicquery rewriting rules that abstract usersfrom the query language of Hive(HiveQL). This allows them to enterregular SQL queries in the webapplication which are translated intoHiveQL using the basic rewriting rules.

This system is different from AWS inthe sense that our cloud infrastructure iscompletely private versus AWSsinfrastructure that is in the publicdomain.This distinguishing factor makes ourinfrastructure trusted over the AWS

infrastructure where data must be storedin an encrypted format since AWS is inthe public domain. In the future we plan

to extend our work to include both,public and private clouds.


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Evolution of Cloud

Storage as Cloud

Computing

Infrastructure

Service

R. Arokia Paul Rajan, S.Shanmugapriyaa

Private and Public clouds serve as thebackbone for a variety of different cloudcomputing service models.

Currently the industry has been

successfully adopting three commontypes of cloud computing servicemodels.

Infrastructure as a Service (IaaS), is aservice model around servers (compute

power), storage capacity, and networkbandwidth. Examples include AmazonEC2 and S3, Rackspace, AT&T, andVerizon.

Platform-as-a-Service (PaaS) providesan externally managed platform for

building and deploying applications andservices. This model typically providesdevelopment tools such as databases anddevelopment studios for working withthe supplied frameworks, as well as theinfrastructure to host the builtapplication. Examples includeForce.com, Microsoft Azure, andGoogle App Engine.

Software-as-a-Service (SaaS) is simplyhaving a software system running on acomputer that doesn't belong to thecustomer and isn't on the customers

premises. It is based on the concept ofrenting an application from a service

provider rather than buying, installingand running software yourself.

No need to invest any capital on storagedevices.

No need for technical expert to maintainthe storage, backup, replication andimportantly disaster management.

Allowing others to access your data willresult with collaborative working styleinstead of individual work.

A Cloud Storage ApplicationProgramming Interface (API) is amethod for access to and utilization of acloud storage system. The most


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common of these kinds are REST(REpresentational State Transfer)although there are others, which are

based on SOAP (Simple Object AccessProtocol).

All these APIs are associated withestablishing requests for service via theInternet. REST is a concept widelyrecognized as an approach to "quality"scalable API design. One of the mostimportant features of REST is that it is a"stateless" architecture.

This means that everything needed tocomplete the request to the storage

cloud is contained in the request, so thata session between the requestor and thestorage cloud is not required.

A Secure Model for

Cloud Computing

Based Storage and

Retrieval

Yaga Reddemma, LingalaThirupathi, Sreekanth Gunti

The proposed business model separatesdata storage service from that ofencryption and decryption service. This

paper uses CRM concept to demonstratethe new mechanism proposed.

In the proposed system the party thatuses cloud storage services must encryptdata before sending it to cloud while theservice provider who is responsible forencryption/decryption must delete dataonce encryption/decryption process iscompleted.

This separation is required as the cloudserver administrators might have illegalaccess to data of the users. To prevent

this, the services such as storage andencryption/decryption are separated andmoved to different cloud servers.Generally users use cloud environmentfor specific purposes. For instancesSAPs ERP services, Salesforce.coms

CRM service and so on. The datagenerated by these operations is saved tocloud storage. However, this studyadvocates an additional cloud server thattakes care of encryption/decryption

activities which are independent ofstorage service.


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First of all users credentials are

authenticated by CRM cloud service.Once authentication is done user canaccess CRM server through which he

performs data retrieval and data storageoperations. As per the users instructions

the CRM cloud service interacts withstorage cloud service and makes datausage request. Then the storage cloudservice sends encrypted data which isavailable in to encryption/decryptionservice and requests for decryption. Theencryption/decryption service takesencrypted data and simply decrypts itand sends the decrypted data to CRM

cloud service. SSL (Secure SocketsLayer) is used for encryption anddecryption purposes. The last step is thatthe CRM cloud service sends requesteddata to end user. Thus securecommunication is taking place across allcomponents as part of proposed dataretrieval mechanism.

After due authentication, the end userssends data storage request to CRMcloud service.In turn the CRM cloud service sendsunencrypted data toencryption/decryption cloud service.The encryption/decryption cloud serviceactually encrypts the given content andsends it to storage cloud service where itis stored. Then the storage cloud servicesends resultant message to CRM cloudservice, which is then displayed to the

user.


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Chapter 3

DESIGN AND ARCHITECTURE

3.1 Eucalyptus Architecture

Fig 3.1 Eucalyptus Architecture

3.1.1 System Architecture:

Cluster

Data Store

Server

Node Controller

Node Controller

Private Cloud

Web Interface or EC2 API

Cloud Controller

Walrus Storage Controller

Regular Network

Fig 3.2 Project System Architecture


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The Node Controller (NC) is part of the Node level of the cloudcomputing architecture. It is written in C and hosts the virtual machineinstances and manages the virtual network endpoints. The NC downloadsand caches images from Walrus as well as creates and caches instances.While there is no theoretical limit to the number of NCs per cluster,

performance limi ts do ex ist.

Cluster Controller (CC)

The Cluster Controller (CC) is written in C and acts as the front end for a clusterwithin a Eucalyptus cloud and communicates with the Storage Controller (SC) and

Node Controller (NC). The CC manages instance (i.e., virtual machines) executionand Service Level Agreements (SLAs) per cluster.

Storage Controller (SC)

The Storage Controller (SC) is written in Java and is the Eucalyptus equivalent toAWS Elastic Block Store (EBS). The SC communicates with the Cluster Controller(CC) and Node Controller (NC) within the distributed cloud architecture andmanages Eucalyptus block volumes and snapshots to the instances within its specificcluster. If an instance requires writing persistent data to memory outside of thecluster, it would need to write to Walrus, which is available to any instance in anycluster. The SC interfaces with storage systems, including local, NFS, iSCSI, andSAN.

VMware Broker (Optional)

The VMware Broker is an optional component that provides an AWS-compatibleinterface for VMware environments and physically runs on the Cluster Controller(CC) within the distributed cloud computing architecture. The VMware Brokeroverlays existing ESX/ESXi hosts and transforms Eucalyptus Machine Images(EMIs) to VMware virtual disks. The VMware Broker mediates interactions

between the CC and VMware and can connect directly to either ESX/ESXi hosts orto vCenter Server.


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3.2 Class Diagram:

#Verify User()

#Process Command()

+ID : string

+User Name : string

#Password : string

Controller

-Send Requests to Server()

Node

-Store Files()

-Retrieve Files()

#Delete Files()

Server

+Log-in()

#Store Files()

#Share Files()

#Download Files()

#Delete Files()

+ID : string

#Password : string

#File ID : string

User

#Files

Data Store

1

1 0..*

1

1..*

0..*

-Manage Cloud Server()

-Manage Users()

-Manage Nodes()

-Manage Data Store()

Cloud Administrator

1..*

1

1

1..*

+Maintain Nodes()

-Node List : string

Cluster

+Maintain Clusters()

-Cluster List : string

Cloud

-Data Store Information

Storage

+Manage Storage()

Walrus

1*

1

*

1

*

1

*

1

*

Fig 3.3 Class Diagram


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3.3 Use Case Diagram :

User

Server

Storage

Administrator

Store Files

Share Files

*

* *

*

uses

*

*

*

*

Manage Users

*

*

*

*

Store/Retrieve Data

**

Manage Storage

1

* *

*

*

1Intelligent Storage

Read Share

uses

Read-Write Share

uses

Sign up

** *

*

Login*

* *

*

Fig 3.4 Use Case Diagram


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3.4 Activity Diagram:

Data StoreServerUser

Share FileCheck Share Type

Display Result

Grant Read AccessGrant Write Access

Read

Read-Write

Forward Result

Grant Read Access

Fig 3.5 Activity DiagramSharing a File


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3.5 Sequence Diagram:

User ServerData Store

Send Data to be stored

[Success] Send Notification

Display Result

Forward Data

Set Permissions

Intelligent Storage

Fig 3.6 Sequence DiagramFile Upload


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3.6 Experiment Setup:

The Private Cloud is implemented in a virtual environment using VMware.

The Cloud used here is Ubuntu Enterprise Cloud.

The Server includescloud controller, cluster controller, storage controller,

Walrus Storage service.

The complete installation procedure is very detailed and thus only basic stepsare mentioned here.

Install and Configure the Node Controller(s)

Installing the Eucalyptus Node Service on a running Ubuntu system consistsof doing the following on one or more systems:

1.

Install Ubuntu 10.04 Server

Fig 3.7 Install Screen


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2. Update to the most current state in the Ubuntu archive:

sudo apt-get update

sudo apt-get dist-upgrade

3.

Install the eucalyptus-nc package

sudo apt-get install eucalyptus-nc

4.

Install the Node controller on a different Virtual Machine.5. Repeat steps 2 and 3 for the node controller.6.

Finally, you need to install the Cloud Controller's eucalyptususer's public sshkey into the Node Controller's eucalyptus user's authorized_keys file. Theeasiest way to do this:

1. On the Node Controller, temporarily set a password forthe eucalyptususer:

o sudo password eucalyptus

2. Then, on the Cloud Controller:

o sudo -u eucalyptus ssh-copy-id -i ~eucalyptus/.ssh/id_rsa.pub

eucalyptus@

3. You can now remove the password of the eucalyptusaccount on theNode:

o sudo password -d eucalyptus

3.6.1 Obtain Credentials

After installing and booting the Cloud Controller, users of the cloud will need toretrieve their credentials. This can be done either through a web browser, or at the

command line.

From a Web Browser1.

From your web browser (either remotely or on your Ubuntu server) access thefollowing URL:

https://:8443/Important!You must use a secure connection, so make sure you use "https"not "http" in your URL. You will get a security certificate warning. You willhave to add an exception to view the page. If you do not accept it you will not

be able to view the Eucalyptus configuration page.

2.

Use username 'admin' and password 'admin' for the first time login (you will beprompted to change your password).


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3. Then follow the on-screen instructions to update the admin password and emailaddress.

4. Once the first time configuration process is completed, click the 'credentials'tab located in the top-left portion of the screen.

5. Click the 'Download Credentials' button to get your certificates

6. Save them to ~/.euca

7. Unzip the downloaded zipfile into a safe location (~/.euca)

unzip -d ~/.euca mycreds.zip

From a Command Line

1.

Alternatively, if you are on the command line of the Cloud Controller, you canrun:

2.

mkdir -p ~/.euca3. chmod 700 ~/.euca4.

cd ~/.euca5. sudo euca_conf --get-credentials mycreds.zip6. unzip mycreds.zip7. ln -s ~/.euca/eucarc ~/.eucarc

3.6.2 Extracting and Using Your Credentials

Now you will need to setup EC2 API and AMI tools on your server using X.509certificates.

1.

Install the required cloud user tools:

sudo apt-get install euca2ools2. To validate that everything is working correctly, get the local cluster

availability details:

3. . ~/.euca/eucarc4. euca-describe-availability-zones verbose5.

AVAILABILITYZONE myowncloud 192.168.1.16. AVAILABILITYZONE |- vm types free / max cpu ram disk7.

AVAILABILITYZONE |- m1.small 0004 / 0004 1 192 28. AVAILABILITYZONE |- c1.medium 0004 / 0004 1 256 5

9.

AVAILABILITYZONE |- m1.large 0002 / 0002 2 512 1010.AVAILABILITYZONE |- m1.xlarge 0002 / 0002 2 1024 20
https://help.ubuntu.com/community/UEC/Credentials?action=AttachFile&do=upload_form&ticket=00527bc3d5.b9d1d30e7ea91d58b5da583d7ed7d389866fd690&target=UECcredentials-2.png


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AVAILABILITYZONE |- c1.xlarge 0001 / 0001 4 2048 20

3.6.3 Install an image from the store

The following is by far the simplest way to install an image. However, advanced

users may be interested in learning how to Bundle their own image.The simplest way to add an image to UEC is to install it from the Image Store on theUEC web interface.

1.

Access the web interface at the following URL (Make sure you specify https):

https://:8443/

2.

Enter your login and password (if requested, as you may still be logged in fromearlier)

3.

Click on the Store tab

Fig 3.10 UEC store4.

Browse available images

5.

Click on install for the image you want

Once the image has been downloaded and installed, you can click on "How to run?"that will be displayed below the image button to view the command to execute toinstantiate (start) this image. The image will also appear on the list given on theImage tab.


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Fig 3.11 UEC Images

3.6.4 Run an Image

There are multiple ways to instantiate an image in UEC:1. Use the command line

2. Use one of the UEC compatible management tools such as Landscape

3.

Use theElasticFox extension to FirefoxHere we will describe the process from the command line:

1. Before running an instance of your image, you should first create a keypair(ssh key) that you can use to log into your instance as root, once it boots. Thekey is stored, so you will only have to do this once. Run the followingcommand:

2.

if [ ! -e ~/.euca/mykey.priv ]; then3. mkdir -p -m 700 ~/.euca4. touch ~/.euca/mykey.priv5. chmod 0600 ~/.euca/mykey.priv6. euca-add-keypair mykey > ~/.euca/mykey.priv7.

fi

Note:You can call your key whatever you like (in this example, the key iscalled 'mykey'), but remember what it is called. If you forget, you can alwaysrun euca-describe-keypairs to get a list of created keys stored in the system.

8. You must make sure to source ~/.euca/eucarc before you run any of theeucatools. It is probably best to add this to the bottom of your .bashrc script.

9. You must also allow access to port 22 in your instances:

euca-authorize default -P tcp -p 22 -s 0.0.0.0/0

10.Next, you can create instances of your registered image:

euca-run-instances $EMI -k mykey -t m1.small
https://help.ubuntu.com/community/UEC/ElasticFoxhttps://help.ubuntu.com/community/UEC/ElasticFox


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Note:If you receive an error regarding image_id, you may find it by viewingImages page or click "How to Run" on the Store page to see the samplecommand.

11.The first time you run an instance, the system will be setting up caches for the

image from which it will be created. This can often take some time the firsttime an instance is run given that VM images are usually quite large. Tomonitor the state of your instance, run:

watch -n5 euca-describe-instances

In the output, you should see information about the instance, including its state.While first-time caching is being performed, the instance's state will be'pending'.

12.

When the instance is fully started, the above state will become 'running'. Lookat the IP address assigned to your instance in the output, then connect to it:

13.IPADDR=$(euca-describe-instances | grep $EMI | grep running | tail -n1 | awk

'{print $4}')

ssh -i ~/.euca/mykey.priv ubuntu@$IPADDR

14.And when you are done with this instance, exit your SSH connection, thenterminate your instance:

15.

INSTANCEID=$(euca-describe-instances | grep $EMI | grep running | tail -n1 |awk '{print $2}')

euca-terminate-instances $INSTANCEID

The Node uses the node controller and the server uses the cloud controller,cluster controller and the storage controller.

After installing and configuring server and node check the servers IP addressusing :

o Ifconfig

Update the server and node using :

o

sudo apt-get updateo sudo apt-getu upgrade


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Test the server-node connection using:

o ping

Install desktop on the node using:

sudo apt-get install ubuntu-desktop

On the nodes browser, connect to the server by giving the address

https://:8443/

Perform first time configuration.

On the server side run :

o

sudo vi /usr/lib/python2.6/dist-packages/imagestore/lib/fetch.py

Add the following lines after line 142 :

o

curl.setopt(pycurl.SSL_VERIFYPEER, 0)o curl.setopt(pycurl.SSL_VERIFYHOST, 0)

Save and close the file.

Get certificates for the server using:

o sudo wgetP /usr/local/share/ca-certificates/ --no-check-certificatehttps://certs.godaddy.com/repository/gd-class2-root.crthttps://certs.godaddy.com/repository/gd_intermediate.crt

https://certs.godaddy.com/repository/gd_cross_intermediate.crt


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Update server certificates using:

o sudo update-ca-certificates

Get the server credentials using:

o mkdir -p ~/.eucao chmod 700 ~/.eucao

cd ~/.eucao sudo euca_conf --get-credentials mycreds.zipo unzip mycreds.zipo ln -s ~/.euca/eucarc ~/.eucarco cd

Install euca tools using:

o sudo apt-get install euca2ools

Get availability details using:

o . ~/.euca/eucarc

o

euca-describe-availability-zones verbose

On the node side, open the server login page; go to the store tab anddownload the image suitable for the cloud used.

Create a key-pair using:


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o if [ ! -e ~/.euca/mykey.priv ];mkdir -p -m 700 ~/.eucao touch ~/.euca/mykey.privo chmod 0600 ~/.euca/mykey.privo euca-add-keypair mykey > ~/.euca/mykey.priv fi

Source the eucarc file using:o . ~/.euca/eucarc

Allow access to port 22 using:o euca-authorize default -P tcp -p 22 -s 0.0.0.0/0

Run the image using:

euca-run-instances -k mykey -t m1.small


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Chapter 4

Implementation

4.1 Methodology Used:Waterfall Model is adopted as the design process for this project. The

Waterfall development Model is a sequential design processes, in which progress is

seen as flowing steadily downwards (like a waterfall) through the phases of

Requirements Specification, Design, Construction (Implementation or Coding),

Integration, Testing and Debugging (Validation), Installation, and Maintenance.

Fig4.1 Waterfall Model

The selection of waterfall model has the following reasons:

a) Requirements are clear and unambiguous.

b)

Project Reviews are conducted at the end of each phase of the

development.

c) The feedback from the reviews is followed up at the end of each phase

of the development.

Requirements

Design

Construction

Integration

Testing


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4.2 Implementation of the System:The project should be developed as a File sharing website on a private cloud

environment. The website is run on the cloud server and thus can be easily accessed

by the nodes in the cluster. The uploaded files are store on the server and share by

using intelligent storage management. The website consists of the following modules

Sign-up module

Log-in module

File upload module

File index module

File access module

File download module

File share module

File delete module

This is the homepage for the project website. Users can sign-up, log-in, learn how to

use the system and contact the administrators using the various links provided at the

bottom of the website.

Fig 4.2 Home Page


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4.2.1 Sign-up module:

In this module the user registers on the website by giving the appropriate information

such as: User name, Password, Email. When the user clicks the Register button the

server creates a folder for the user where the files uploaded by the user will be saved.

Fig 4.3 Sign up Page


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4.2.2 Log-in module:

The user uses this screen to log-in to the website. If the user provides the correctcredentials, they are logged in to the system and their user name is stored in a sessionvariable. After the user has logged in the Sign up and Login links on the bottom

of the website are replaced by Access Files and Upload Files links which giveaccess to upload files and allow the user to access the uploaded files respectively.

Fig 4.5 Log-in page


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4.2.3 File Upload module:

After the user has logged in to the system they can upload files to the cloud by usingthe upload module. In this module the user points to the path of the files and clicksupload. The server then checks if any file with the same name is already present. If

yes then it checks whether the user has read or read- write permission. If the user hasonly read permission then Access Denied message will be displayed. If the user

has read- write permission then an Are you sure? message will be displayed to getuser confirmation before uploading the file to the server. If the file doesnt exist inthe database then the file is simply uploaded. After uploading an entry for the file iscreated in the database with the readand writepermission set to the user or if filealready exists on the server the database entry is updated.

Fig 4.6 Upload Page


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Fig 4.7 File successfully uploaded

Fig 4.8 Confirm Replace Page


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4.2.4 File index module:

After the user has uploaded one or more files, they can access the uploaded files byusing the file index module. When the user clicks the Access files link the server

accesses the file table in the database and finds the files for which the user has read

or write permission and retrieves them. These files are displayed in a table formatwith three columns: File Name, Uploaded by and Last Updated. The File names

are displayed as a link and by clicking the links the user can access the respectivefiles.

Fig 4.9 File Index


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4.2.5 File Access module:

The user accesses the individual files using the file access module. In this module thefile is retrieved from storage and displayed to the user. If the user has only read

permission then they can only view and download the file. If the user has read and

write permissions then the user can share, download and delete the uploaded file. Onthe left hand side of the webpage, information about the file is displayed. Thisincludes: File name, Uploaded by, File size and Last updated.

Fig 4.10 Access File


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4.3.6 File Download module:

The user downloads the file using the download module. In this module the relevantfile is accessed in storage, its data is read and outputted to the user in the form of afile. The method of download varies based on browser and users softwares.

Fig 4.11 File Download


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4.2.7 File Share Module:

The user shares the uploaded file using the file share module. In this module the userfirst gives the ID of the user to which file should be shared and then gives the type ofsharing to be done, whether it is a read share or a read-write share. When the user

clicks the share button the server checks the type of share that the user has chosenand updates the privileges accordingly. There is no real sharing of files done here(thought that can be easily added), but rather granting permission to access theuploaded files. The shared files are shown to the appropriate user when they try toaccess the uploaded files.

Fig 4.12 File Share

Fig 4.13 Shared File


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4.2.8 File Delete module:

The user deletes the uploaded files using the delete module. When the user isviewing the uploaded file, if they click the Delete link then they are forwarded to

the delete module. First the website checks whether the user has read-write privilege

and if yes it then asks the user for confirmation before deleting the file. If the userconfirms deletion the file is deleted and the associated entry in the database table isremoved.

Fig 4.14 Confirm Deletion

Fig 4.15 File Deleted


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4.3 Testing -Unit Test Case Specification

4.3.1 UTC 1 - Test whether the website can be accessed within the

cluster.

Test Case ID UTC 1

Test Case Description Test whether the output of the application deployed inUbuntu is displayed correctly.

Expected Output The output of the application should be displayed.

Test Setup The application starts running in the

Test Procedure

Step Input Expected Output

1. User types the address in thebrowser

The application displays the output inthe browser


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4.3.2 UTC 2Test whether the user is able to register

Test Case ID UTC 2

Test Case Description Test whether the user is able to register to upload a file.

Expected Output The output of the application should display that the useris successfully registered to upload a file

Test Setup The application deployed takes the values given andvalidates the user as a new user.

Test Procedure


1. User types only the username/onlypassword or username & passwordonly and clicks enter.

The application asks for a passwordor email id .

2. User types the password andconfirm password differently

The applications displays the outputas passwords dont match

3. The passwords match and user nameand all are specified

The output is displayed assuccessfully registered.


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4.3.3 UTC 3Test whether the user is able to upload files

Test Case ID UTC 3

Test Case Description Test whether the user is able to upload a file.

Expected Output The output of the application should display that the userhas successfully uploaded the file

Test Setup The application deployed validates the user and uploadsthe file as he wishes.

Test Procedure


1. User selects the file from the diskand clicks submit

The application accepts it and loadsthe file into the cloud.

2. User selects a very large file The applications displays that verylarge files cant be uploaded

3. The user selects an empty file The output is displayed as 0kb fileuploaded.


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Fig 4.16 File Uploaded

4.3.4 UTC 4Test whether another user is able to access uploaded

files

Test Case ID UTC 4

Test Case Description Test whether another user is able to see the uploaded file.

Expected Output The output of the application should display that the useris able to see another

Test Setup The application deployed is able to display the uploadedfiles to the user once


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Test Procedure


1. User types only the username/onlypassword and clicks enter.

The application asks for a password.

2. User types the password differently The applications displays the outputas wrng password

3. The user successfully logs in andclicks access files

The output is displayed with the filesthat have been uploaded by him andthose files which have been shared tohim.

Fig 4.17 File Index view


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4.3.5 UTC 5Test whether the user is able to download files

Test Case ID UTC 5

Test Case Description Test whether the user is able to download an uploadedfile.

Expected Output The output of the application should display that the useris able to download and save it in a desired location

Test Setup The application deployed downloads the file uploaded

Test Procedure


1. User successfully logs in The application displays theusername and he can access orupload files.

2. User accesses the files stored in thecloud

The application displays the output asa table with the list of files that have

been uploaded

3. The user clicks on the file andselects download

A window pops up with a messageon where to store the file .


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4.3.6 UTC 6Test whether the user is able to share the upload files

Test Case ID UTC 6

Test Case Description Test whether the user is able to share the uploaded file.

Expected Output The output of the application should display that theusers enabled in the share are able to access those files.

Test Setup The application deployed takes the username of those towhom the files are to be shared.

Test Procedure


1. User types a valid username andclicks share

The application asks for the mode ofsharing whether it is read or readwrite

2. User types The applications displays the output

as passwords dont match

3. The passwords match and user nameand all are specified

The output is displayed assuccessfully registered.


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Fig 4.18 File Share Test

Fig 4.19 File Share Test 2


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4.3.7 UTC 7Test whether the user is able to delete the uploaded

file(s)

Test Case ID UTC 7

Test Case Description Test whether the user is able to delete the uploaded file.

Expected Output The output of the application should display that a filehas been deleted from the storage cloud

Test Setup The application deployed selects the name of the file tobe removed and deletes it accordingly

Test Procedure


1. A user who has uploaded a fileclicks the access file option

The list of files uploaded aredisplayed in a table.

2. The user then clicks the file whichhe had uploaded

The output is a new window with 3options like download , share anddelete.

3. The user clicks the delete option The output is displayed as a pop upsaying that the user is about to deletethe file permanently.

1.

The user clicks on submit The file is deleted permanently from

the cloud.


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Chapter 5

CONCLUSION AND FUTURE WORK

5.1 ConclusionThe website has been successfully developed and deployed in the private cloudenvironment. Thus the website provides file upload, file download and file sharingfeatures and uses intelligent storage management mechanisms to increase securityand the efficiency of memory management. This website can be easily deployed inany private cloud environment to promote file sharing.


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5.2 Future Work:

This can be extended to a large software application which requires

secured file storage, secured file access and a secured file sharing,uploading facility in a cloud based environment. The application can alsoimprove the existing storage mechanism facility of any currentlydeployed cloud storage application. The application can also be usefulfor integrating other cloud storage facility so as to enhance security,transparency, simplicity for small as well as large files. The applicationcan be useful for simplifying the cloud storage mechanism by ensuringthat cloud storage need not require an expounding method to providesuch a facility.


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References:

[1]. Sankaran Sivathanu, Ling Liu, Mei Yiduo and Xing Pu, StorageManagement in Virtualized Cloud Environment in IEEE 3rd InternationalConference on Cloud Computing (CLOUD), 2010, PP 204-211.

[2]. Vaibhav Khadilkar, Anuj Gupta, Murat Kantarcioglu, Latifur Khan,Bhavani Thuraisingham, Secure Data storage and Retrieval in the Cloud, in6th International Conference on Collaborative Computing: Networking,Applications and Worksharing (CollaborateCom), 2010, pp 1-8.

[3]. R. Arokia Paul Rajan, S. Shanmugapriyaa, Evolution of Cloud Storage asCloud Computing Infrastructure Service, in arXiv:1308.1303v1 [cs.DC].

[4]. Yaga Reddemma, Lingala Thirupathi , Sreekanth Gunti, A Secure Model

for Cloud Computing Based Storage and Retrieval, in IOSR Journal ofComputer Engineering (IOSRJCE) Volume 6, Issue 1 (Sep-Oct. 2012), pp 01-05 .

[5]. Cong Wang, Qian Wang, Kui Ren, Ning Cao and Wenjing Lou, TowardsSecure and Dependable Storage Services in Cloud Computing, in IEEETransactions on Services Computing, vol. 5, no. 2, pp. 220-232, Second 2012,doi:10.1109/TSC.2011.24 .

[6]. Cong Wang, Qian Wang, Kui Ren, Wenjing Lou Privacy-PreservingPublic Auditing for Data Storage Security in Cloud Computing, in 2010

Proceedings IEEE INFOCOM, pp 1 - 9.

[7]. James Broberg, Rajkumar Buyya, Zahir Tari, MetaCDN: HarnessingStorage Clouds for high performance content delivery, in Journal of

Network and Computer Applications, Volume 32, Issue 5, September 2009,Pages 10121022 .

storage management in private cloud

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