cloud computing final
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complete idea about cloud computingTRANSCRIPT
Cloud ComputingGets its name as a metaphor for the internet
Omer K. JasimPh.D. qualifier examFCIS-ASU’2013
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics 9. References
FCSI, ASU, Egypt. Omer K. Jasim
Definitions
• A large pool of easily usable and accessible virtualized resources (such as hardware, development platforms and/or services).
“ Stallman 2011”.
• A parallel and distributed computing system consisting of a collection of inter-connected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources based on service-level agreements (SLA) established through negotiation between the service provider and consumers. “Nicolas 2013
FCSI, ASU, Egypt. Omer K. Jasim
Cloud computing:- is the provision of dynamically scalable and
often virtualized resources as a service over the internet
(public cloud) or intranet (private cloud).
The “Cloud” is the default symbol of the internet in
diagrams.
Cloud Computing
The broader term of “Computing” encompasses:- no. of Computations- Coordination logic- Storage
Cloud Computing is about moving computing from the single desktop pc/data centers to the internet.
Definition (cont.)
set up an account with the provider, start and configure a
virtual cluster with one or more nodes for computation, and
return the results to your local machine
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics 9. References
FCSI, ASU, Egypt. Omer K. Jasim
Cloud Computing LayersComputer, phones, Browser.
Cloud Services
Networks, Virtualization
Client
Applications
Platform
Infrastructure
Server
FCSI, ASU, Egypt. Omer K. Jasim
1- Clients Hardware and/or software Essentially useless without the cloud Ex: Laptop & phones, Thin and Thick
computer.
FCSI, ASU, Egypt. Omer K. Jasim
Cloud layers (cont.)
Application
Platform
Infrastructure
Cloud
Services
FCSI, ASU, Egypt. Omer K. Jasim
2- Cloud Service
Data Centers ClustersStorage
Other Grids/Clouds
Virtualization
VM Management & Deployment
Amazon S3, EC2
OpenNebula, Eucalyptus
Mosso
Web 2.0 Interface
Programming API
Scripting & ProgrammingLanguages
Google AppEngine
Microsoft Azure
Manjrasoft Aneka
Google Apps (Gmail, Docs,…)
Salesforce.com
Infrastructure as a Service(IaaS)
Platform as a Service(PaaS)
Software as a Service(SaaS)
QoS
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FCSI, ASU, Egypt. Omer K. Jasim
2.1.Software as a Services (SaaS)
- SaaS is a model of software deployment where an application is hosted as a service provided to customers cross the Internet. -Features:
• Multi-tenancy, Multi -instance– One application instance may be serving hundreds of
companies– Opposite of multi-instance where each customer is
provisioned their own server running one instance• Metadata driven configurability
– Instead of customizing the application for a customer (requiring code changes), one allows the user to configure the application through metadata
FCSI, ASU, Egypt. Omer K. Jasim
SaaS Maturity Levels
• Level 1: Ad-Hoc/Custom
• Level 2: Configurable• Level 3: Configurable,
Multi-Tenant-Efficient• Level 4: Scalable,
Configurable, Multi-Tenant-Efficient
Source: Microsoft MSDN Architecture Center
• Level 1: Ad-Hoc/Custom
• Level 2: Configurable• Level 3: Configurable,
Multi-Tenant-Efficient• Level 4: Scalable,
Configurable, Multi-Tenant-Efficient
FCSI, ASU, Egypt. Omer K. Jasim
2.2. Platform as a Services (PaaS)
– Providing all the facilities necessary to support the
complete process of building and delivering web
applications and services, all available over the Internet.
– Entirely virtualized platform that includes one or more
servers, operating systems and specific applications.
Examples:- Middleware, VM, etc..
FCSI, ASU, Egypt. Omer K. Jasim
2.3.Infrastrcture as a Services (IaaS)
– Provision model in which an organization outsources the equipment used to support operations, including storage, hardware, servers and networking components.
– Also known as Hardware as a Service (HaaS).
– Service provider owns the equipment; responsible for housing, running and maintaining it.
– Client typically pays on a per-use basis.Examples:- IBM Blue house, VMWare, Amazon EC2, Microsoft Azure
Platform, Sun Parascale and more
FCSI, ASU, Egypt. Omer K. Jasim
(Customer vs. Provider) view XaaS
3- Server Hardware/Software Specialized for cloud OS, multi core processors Network of virtualized computers
FCSI, ASU, Egypt. Omer K. Jasim
FCSI, ASU, Egypt. Omer K. Jasim
Cloud Architecture The Cloud Computing Architecture of a cloud solution is the structure of the system, which comprise enterprise arch. and cloud resources, services, middleware, and software components, SOA, the externally visible properties of those, and the relationships between them
Service Oriented
Architecture
Enterprise Architecture
Software Architecture
Middleware
Architecture
Cloud ComputingArchitecture
Collection of services , communicate with each other or two or more services coordinate to preform some activities
Any program supported “glue together”, allow programs written for access to a particular DB.
Structure and operation of an organization
Set of structures needed to reason about the system software
FCSI, ASU, Egypt. Omer K. Jasim
Deployment Models• Public cloud (off-site and remote) : resources
dynamically provisions on the internet
• A private cloud : consolidating shared services on virtualized hardware deployed from a primary datacenter to serve local and remote users (intranet).
• A hybrid cloud environment consists of some portion of computing resources on-site (on premise) and off-site (public cloud).
• A community cloud is formed when several organizations with similar requirements share common infrastructure.
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics9. References
FCSI, ASU, Egypt. Omer K. Jasim
Cloud Data Center • Data center: large server farms + data warehouses.
- managed infrastructure- Supported transmission from web hosting to cloud computing
- individual web/content providers: must provision for peak load.• web hosting: third party provides and owns the (server farm)
infrastructure, hosting web services for content providers• “server consolidation” via virtualization and “ Collaboration mechanism “
FCSI, ASU, Egypt. Omer K. Jasim
WAN Network
Functional Servers
WAN Edge
Data Center Core/ Gateway
Customer Edge
L2 Aggregator
Server Rack
Virtual Server
Application
VM/Server Control
Server
Hypervisor
Virtual Subnet/VLAN 1
Virtual Subnet/VLAN 2
Application
Virtual Machine (VM)
Application
Virtual Machine (VM)
Application
Virtual Machine (VM)
Application
Virtual Machine (VM)
Application
Virtual Machine (VM)
Application
Virtual Machine (VM)
Application
Virtual Machine (VM)
Application
Virtual Machine (VM)
Provisioning, Billing, Security, Load Balancing, Monitoring, Auditing, Logging, and ETC.
Functional Servers
Collaboration level
Basic components
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics.9. References
FCSI, ASU, Egypt. Omer K. Jasim
Main Process- Migration Process - Transmitted the enterprise application
from the desktop to open cloud environment.
- Virtualization - Abstraction of computer resources. - Hides the physical characteristics of
computing resources from their users, be they applications, or end users.
FCSI, ASU, Egypt. Omer K. Jasim
Migration to the Cloud - Move the enterprise application to the
open cloud environment, captive cloud data center
- Implemented in one of the several ways:
(code, architecture, and usage )- The migration of an enterprise
application is based capture by the following:
P P’C+P’l P’OFC+P’l
FCSI, ASU, Egypt. Omer K. Jasim
Optimize
Assess
Test Augment
Re- architect
Map
Isolate
Start
End
Migration Life Cycle
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics 9. References
FCSI, ASU, Egypt. Omer K. Jasim
Virtualization • Virtualization:- the abstraction of computer
resources. • Virtualization hides the physical characteristics of
computing resources from their users, be they applications, or end users.
• This includes making a single physical resource (such as a server, an operating system, an application, or storage device) appear to function as multiple virtual resources; it can also include making multiple physical resources (such as storage devices or servers) appear as a single virtual resource.
FCSI, ASU, Egypt. Omer K. Jasim
VM-Architecture
Hardware
Virtual Machine Monitor (VMM) / Hypervisor
Guest OS(Linux)
Guest OS(NetBSD)
Guest OS(Windows)
VM VM VM
AppApp AppAppAppXen
VM-Ware
UML
Denali
etc.Hypervisor is a software program that manages multiple operating systems (or multiple instances of the same operating system) on a single computer system. The hypervisor manages the system's processor, memory, and other resources to allocate what each operating system requires. Hypervisors are designed for a particular processor architecture and may also be called virtualization managers.
FCSI, ASU, Egypt. Omer K. Jasim
Full Virtualization
• Provides a complete simulation of the underlying hardware.
• The result is a system in which all software (including all OS’s) capable of execution on the raw hardware can be run in the virtual machine.
• Comprehensively simulate all computing elements as instruction set, main memory, interrupts, exceptions, and device access.
• Full virtualization is only possible given the right combination of hardware and software elements.
FCSI, ASU, Egypt. Omer K. Jasim
Para virtualization
Do not try to emulate everything , • Work as a guard • Pass safe instructions directly to CPU and
device• Guests have some exposure to the
hardware
• Better performance
• Need to slightly modify guest OS, but no need to modify applications
• Xen, Sun Logical Domains
FCSI, ASU, Egypt. Omer K. Jasim
Cloud based virtualization• PROVIDER - Support cloud to improve IT efficiency, agility and reliability. - Delivers everything IT needs to build, operate,
rent, and manage their cloud. . CUSTOMER- Helps customers evolve technical foundations, organizational models, operational processes and financial measures to establish both a cloud infrastructure and cloud operations model.
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics 9. References
FCSI, ASU, Egypt. Omer K. Jasim
Integration of Cloud Computing
• Important factor in the cloud.• Data enterprise and applications must
be linked up via one or more standard integration platform .
• Integration middle (I-MW or C-MW) ware simplify the mapping between Application to Application (A2A), Application to Cloud (A2C), Cloud to Cloud(C2C).
FCSI, ASU, Egypt. Omer K. Jasim
Cloud -MW
• Cloud middleware will be made available as a service.
• Due to varying integration requirements and scenarios, there are a number of middleware technologies and products.
• For performance sake, clusters, fabrics, grids, and federations of hubs, brokers, and buses are being leveraged.
FCSI, ASU, Egypt. Omer K. Jasim
Cloud-MW
App1
App2
ISB
Pub. Cloud ISB
Cloud Cloud ISB
Application
App2App
App2C
C2C
FCSI, ASU, Egypt. Omer K. Jasim
Understanding
Testing
Design
Definition
Integration life cycle
Understanding the source system or the application on this system, target system
Acquire information from previous phase to define the metadata, physical attribute, relation ship between objects
Determined the data extract from the one or more system to target system
Assuring the integration is done
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics9. References
Service Level Agreement in Cloud• Framework for provider, costumer .• Negotiation between service consumer and service
provider, records common understanding about services.
• Guarantee multiple QoS parameters across layers, highly dynamic environments, resources heterogeneity, Xaas service definition.
• Capacity Planning:- dynamic workload amount, customer satisfaction level,• Maximize the profit: by reducing the resource cost (the number and type of initiated virtual machines and penalties cost).
FCSI, ASU, Egypt. Omer K. Jasim
FCSI, ASU, Egypt. Omer K. Jasim
SLA-life Cycle
FCSI, ASU, Egypt. Omer K. Jasim
• Infrastructure SLA. The infrastructure provider manages and offers guarantees on availability of the infrastructure, namely, server machine, power, network connectivity, and so on.
• Application SLA. In the application co-location hosting model, the server capacity is available to the applications based solely on their resource demands.
SLA-Type
FCSI, ASU, Egypt. Omer K. Jasim
SLA HierarchySLA at an upper layer depends on SLAs at lower layers.
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Workflow Management System7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics 9. References
FCSI, ASU, Egypt. Omer K. Jasim
Cloud Workflow (CW)
• A process consist of a series of steps that simplifies the complexity of execution and management of application.
• Data Management • Data replication• Data Placement • Intermediate data storage
FCSI, ASU, Egypt. Omer K. Jasim
FCSI, ASU, Egypt. Omer K. Jasim
CW: Data Management
• New features in cloud computing
– Independent of users and provider– Cost driven
• computation cost, storage cost, data transfer cost
– Data dependency• Task – data, data – data.
• Some research issues
– Data partition, placement, replication, synchronisation.
Example : Aneka, open Nebula .
FCSI, ASU, Egypt. Omer K. Jasim
CW: Data Placement
• Data Placement: to decide where to store the application data in the distributed data centres
• Aims:
– Reduce data movement – Reduce task waiting time
• Strategy:
– Data dependency: dataset – dataset
FCSI, ASU, Egypt. Omer K. Jasim
CW: Data Replication
• Data replication: for one dataset, store several copies in different places (data centres)
• Aims:
– Increase data security– Fast data access– Reduce data movement
• Strategy:
– Dynamic replication.
FCSI, ASU, Egypt. Omer K. Jasim
CW: Intermediate Data Storage
• Intermediate data storage is especially importance in scientific workflows
• Aim:
– Reduce system cost• Strategy:
– Intermediate data can be regenerated with data provenance information
– Selectively store some key intermediate datasets
FCSI, ASU, Egypt. Omer K. Jasim
Agenda 1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Cloud Workflow system7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics 9.References
FCSI, ASU, Egypt. Omer K. Jasim
Cloud Computing Parallelism • “Cloud” refers to large Internet services
like Google, Yahoo, etc. that run on 10,000’s of machines
• - Want to parallelize across hundreds/thousands of CPUs– How to parallelize– How to distribute
-Map-Reduce model based to answer the above questions.
FCSI, ASU, Egypt. Omer K. Jasim
Map –Reduce • Map-Reduce is a data processing
approach(data parallel programming model) that presents a simple programming model for processing highly parallelizable data sets. It is implemented as a cluster, with many nodes working in parallel on different parts of the data.
• Pioneered by Google– Processes 20 petabytes of data per day
• Popularized by open-source Hadoop project– Used at Yahoo!, Facebook, Amazon, …
Data Distribution
• Input files are split into M pieces on distributed file system– Typically ~ 64 MB blocks
• Intermediate files created from map tasks are written to local disk
• Output files are written to distributed file system
Assigning Tasks
• Many copies of user program are started
• Tries to utilize data localization by running map tasks on machines with data
• One instance becomes the Master• Master finds idle machines and assigns
them tasks
FCSI, ASU, Egypt. Omer K. Jasim
Master
worker1 Worker nworker3worker2
Data tasks Task1Task2
.
.
.Task n
Data distributed
Assigning to the tasks
Example for MapReduce
• Page 1: computer study is good• Page 2: cloud computing is good• Page 3: my study in cloud computing • …….• …..• Page n.: ….. Any data ?
Map output
• Worker 1: – (computer 1), (study 1), (is 1), (good 1).
• Worker 2: – (cloud 1), (computing 1), (is 1), (good 1).
• Worker 3: – (My 1), (study 1), (in 1), (cloud 1), (computing 1).
FCSI, ASU, Egypt. Omer K. Jasim
Map Operation
MAP: Input data <key, value> pair
DataCollection: split1
web 1
weed 1
green 1
sun 1
moon 1
land 1
part 1
web 1
green 1
… 1
KEY VALUE
Split the data toSupply multipleprocessors
DataCollection: split 2
DataCollection: split n
Map
……
Map
web 1
weed 1
green 1
sun 1
moon 1
land 1
part 1
web 1
green 1
… 1
KEY VALUE
web 1
weed 1
green 1
sun 1
moon 1
land 1
part 1
web 1
green 1
… 1
KEY VALUE
web 1
weed 1
green 1
sun 1
moon 1
land 1
part 1
web 1
green 1
… 1
KEY VALUE
web 1
weed 1
green 1
sun 1
moon 1
land 1
part 1
web 1
green 1
… 1
KEY VALUE
…
Reduce Input• Worker 1:
– (computer 1)• Worker 2:
– (is 1), (is 1)• Worker 3:
– (good 1), (good 1)• Worker 4:
– (study 1), (study1)• Worker 5:
– (cloud 1), (cloud 1)• Worker 6:
– (computing 1), (computing 1)•Worker 6: - (My 1)
Reduce Output• Worker 1:
– (computer 1)• Worker 2:
– (is 2)• Worker 3:
– ( good 2)• Worker 4:
– (study 2)• Worker 5:
– (cloud 2)
FCSI, ASU, Egypt. Omer K. Jasim
Reduce Operation
MAP: Input data <key, value> pairREDUCE: <key, value> pair <result>
Reduce
Reduce
Reduce
DataCollection: split1 Split the data to
Supply multipleprocessors
DataCollection: split 2
DataCollection: split n Map
Map
……
Map
…
FCSI, ASU, Egypt. Omer K. Jasim
CountCount
Count
worker1
Worker n
Parse-hash
worker2
Map <key, 1> Reducers (say, Count)
P-0000
P-0001
P-0002
, count1
, count2
,count3
Work 3
Parallel Execution
No. of CPU.
Mapping
Fault Tolerance
• Network Failure: – Detect failure via periodic heartbeats – Re-execute completed and in-progress map tasks – Re-execute in progress reduce tasks – Task completion committed through master
• Master failure: – Could handle, but don't yet (master failure unlikely)
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Cloud Workflow system7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Dissertation with this topics 9.References
FCSI, ASU, Egypt. Omer K. Jasim
Cloud Federation• Cloud Federation is a collection of individual
Cloud providers, which collaborate by trading resources (e.g. computing, storage).
• Desired feature of Cloud– Illusion of infinite computing resources
• Resources available in a single data center are limited– A large demand may put pressure in the data
center capacity– One possible source for additional resources is
idling resources from other providers
FCSI, ASU, Egypt. Omer K. Jasim
- A user submit an application to the federation, the federation select provider to run application.
Cloud federation
provider1provider2 Provider 3 Provider n
FCSI, ASU, Egypt. Omer K. Jasim
Cloud Federation Motivations
• Obtain extra resources from other members (Outsourcing)– Avoid losing customers– Avoid losing reputation by violating SLAs
• Lease idle resources (Contributing to Federation(– Avoid wasting their non-storable compute resources
• Supplying resources in specific geographic locations– Low-latency access regardless of location– meet regulations in place for the customers
• Disaster recovery
FCSI, ASU, Egypt. Omer K. Jasim
Cloud storage
• Cloud storage enables to “throw” data into the cloud and without worrying about how it is stored or backing it up. When you need it again, you simply reach into the cloud and grab it.
• User don’t know how it is stored, where it is stored, or what has happened to all the pieces of hardware between the time you put it in the cloud and the time you retrieved it.
FCSI, ASU, Egypt. Omer K. Jasim
Yesterday’s storage
Local storage
StorageServers
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Today’s storage
e.g. Google Laptop Cloud Storage
FCSI, ASU, Egypt. Omer K. Jasim
Internet-service FS:GoogleFS, HadoopFS, CloudStore, ...
Custom Storage:Facebook Haystack Photo Store, Microsoft StarTrack (Map Apps),
Amazon S3, EBS, ...
Key-Value Store:Cassandra, Voldemort, ...
Structured Storage:Yahoo! PNUTS, Google BigTable, Hbase, ...
+ Replication+ Scale-up+ Migration+ ...
Reliable?
Highly-available?
FCSI, ASU, Egypt. Omer K. Jasim
Agenda1. Cloud Computing Definitions2. Cloud Computing Layers 2.1 Cloud Architecture 2.2 Cloud Data Center3. Main Cloud Process 3.1 Cloud Migration 3.2 Virtualization 4. Integration of Cloud Application5. SLA’s in Cloud Computing6. Cloud Workflow system7. Cloud Computing Parallelism 7.1 Map-Reduce Model 7.2 Cloud Federation 8. Our Dissertation with this topics 9. References
FCSI, ASU, Egypt. Omer K. Jasim
Our Dissertation - Cloud computing environment introduce more
features in on-demand scalability/elasticity, affordability, global-scale accessibility.
- All above features are done in open environments, therefore it vulnerable to many types of attacks.
- Our dissertation attempt to provide a hybrid cryptography model based on CipherCloud and Quantum Cryptography to present a new concept in cloud security world.
FCSI, ASU, Egypt. Omer K. Jasim
References 1- George Reese, “Cloud Application Architectures” USA, 2009.2- Zaigham Mahmood and Richard Hill, Cloud Computing for
Enterprise Architectures. ©Springer-Verlag London Limited 2011
3- Rajkumar Buyya and James Broberg, CLOUD COMPUTING “Principles and Paradigms”, 2011 by John Wiley.
4- Anthony T. Velte and Robert Elsenpeter, Cloud Computing:“A Practical Approach”© 2010 by The McGraw-Hill Companies