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1What is Cloud?
2The term Cloud refers to a Network or Internet. In other words, we can say that Cloud is something which is present at remote location. Cloud can provide services over network i.e. on public networks or on private networks i.e. WAN, LAN or VPN.
3
4Applications such as e-mail, web conferencing, customer relationship management (CRM), all run in cloud.
5What is Cloud Computing?
6Cloud Computing refers to manipulating, configuring, and accessing the applications online. It offers online data storage, infrastructure and application.
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8cloud_computing Tutorial
9We need not to install a piece of software on our local PC and this is how, the cloud computing overcomes platform dependency issues. Hence, the Cloud Computing is making our business application mobile and collaborative.
10Cloud Computing Technologies
11There are certain technologies that are working behind the cloud computing platforms making cloud computing flexible, reliable, usable. These technologies are listed below:
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13Virtualization
14
15Service-Oriented Architecture (SOA)
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17Grid Computing
18
19Utility Computing
20
21Virtualization
22Virtualization is a technique which allows to share single physical instance of an application or resource among multiple organizations or tenants(customers). It does so by assigning a logical name to a physical resource and providing a pointer to that physical resource when demanded.
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24cloud_computing Tutorial
25The Multitenant architecture offers virtual isolation among the multiple tenants and therefore, the organizations can use and customize the application as though, they each has its own instance running.
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27Service-Oriented Architecture(SOA)
28Service-Oriented Architecture helps to use applications as a service for other applications regardless type of vendor, product or technology. Therefore it is possible to exchange of data between applications of different vendors without additional programming or making changes to services.
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30cloud_computing-service_oriented_architecture cloud_computing Tutorial
31Grid Computing
32Grid Computing refers to distributed computing in which a group computers from multiple locations are connected with each other to achieve common objective. These computer resources are heterogeneous and geographically dispersed.
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34Grid Computing breaks complex task into smaller pieces. These smaller pieces are distributed to CPUs that reside within the grid.
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36cloud_computing Tutorial
37Utility Computing
38Utility computing is based on Pay per Use model. It offers computational resources on demand as a metered service. Cloud computing, grid computing, and managed IT services are based on the concept of Utility computing
39
40Cloud Computing Architecture
41The Cloud Computing architecture comprises of many cloud components, each of them are loosely coupled. we can broadly divide the cloud architecture into two parts:
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43Front End
44
45Back End
46
47Each of the ends are connected through a network, usually via. Internet. The following diagram shows the graphical view of cloud computing architecture:
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49cloud_computing Tutorial
50Front End
51Front End refers to the client part of cloud computing system. It consist of interfaces and applications that are required to access the cloud computing platforms. Eg. Web Browser
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53Back End
54Back End refers to the cloud itself. It consist of all the resources required to provide cloud computing services. It comprises of huge data storage, virtual machines, security mechanism, services, deployment models, servers etc.
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56Cloud Infrastructure Components
57Cloud infrastructure consist of servers, storage, network, management software, and deployment software and platform virtualization.
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59cloud_computing Tutorial
60Hypervisor
61Hypervisor is a firmware or low level program that acts as a Virtual Machine Manager. It allows to share the single physical instance of cloud resources between several tenants.
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63Management Software
64Management Software helps to maintain and configure the infrastructure.
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66Deployment Software
67Deployment software helps to deploy and integrate the application on the cloud.
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69Network
70Network is the key component of cloud infrastructure. It allows to connect cloud services over the internet. It is also possible to deliver network as a utility over the internet i.e. the consumer can customize the network route and protocol.
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72Server
73Server helps to compute the resource sharing and offer other services such as resource allocation and de allocation, monitoring resources, security etc.
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75Storage
76Cloud uses distributed file system for storage purpose. If one of the storage resource fails then it can be extracted from another one, which makes cloud computing more reliable.
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78Cloud Deployment Models
79Foloowing are the cloud deployment models:
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81Public Cloud Model
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83Private Cloud Model
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85Hybrid Cloud Model
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87Community Cloud Model
88
89Public Cloud Model
90The Public Cloud Model allows systems and services to be easily accessible to general public. e.g. Google, Amazon, Microsoft offers cloud services via internet.
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93BENEFITS
94Cost Effective
95
96Reliability
97
98Flexibility
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100Location Independence
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102Utility Style Costing
103
104High Scalability
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106DISADVANTAGES
107Low Security
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109Less customizable
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111Private Cloud Model
112The Private Cloud allows systems and services to be accessible with in an organization. The Private Cloud is operated only within a single organization. However, It may be managed internally or by third-party.
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115BENEFITS
116Here are the benefits of deploying cloud as private cloud model.
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118Higher Security and Privacy
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120More Control
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122Cost and energy efficiency
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124DISADVANTAGES
125Here are the disadvantages of using private cloud model:
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127Restricted Area
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129Inflexible Pricing
130
131Limited Scalability
132
133Additional Skills
134
135Hybrid Cloud Model
136The Hybrid Cloud is mixture of public and private cloud. Non Critical activities are performed using public cloud while the critical activities are performed using private cloud.
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138BENEFITS
139Here are the benefits of deploying cloud as hybrid cloud model:
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141Scalability
142
143Flexibility
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145Cost Efficiencies
146
147DISADVANTAGES
148Here are the disadvantages of Hybrid Cloud Model:
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150Networking Issues
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152Security Compliance
153
154Infrastructural Dependency
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156Community Cloud Model
157The Community Cloud allows system and services to be accessible by group of organizations. It shares the infrastructure between several organizations from a specific community. It may be managed internally or by the third-party.
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160BENEFITS
161Here are the benefits of deploying cloud as community cloud model:
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163Cost effective
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165Sharing Between Organizations
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167Security
168
169ISSUES
170Since all data is housed at one location, therefore one must be careful in storing data in community cloud because it might be accessible by others.
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172It is also challenging to allocate responsibilities of governance, security and cost.
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174Cloud Service Models
175Following are the cloud service models:
176
177Infrastructure as a Service(IaaS) Model
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179Platform as a Service(PaaS) Model
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181Software as a Service(SaaS) Model
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183Identity as a Service(IDaaS) Model
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185Network as a Service(NaaS) Model
186
187Infrastructure as a Service(IaaS)
188IaaS provides access to fundamental resources such as physical machines, virtual machines, virtual storage etc. Apart from these resource the IaaS also offers:
189
190Virtual machine disk storage
191
192Virtual local area network (VLANs)
193
194Load balancers
195
196IP addresses
197
198Software bundles
199
200All of the above resources are made available to end user via server virtualization. Moreover, these resources are accessed by the customers as if they own them.
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203BENEFITS
204IaaS allows the cloud provider to freely locate the infrastructure over the internet in cost-effective manner. Some of the key benefits of IaaS are listed below:
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206Full Control of the computing resources through Administrative Access to VMs.
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208Flexible and Efficient renting of Computer Hardware.
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210Portability, Interoperability with Legacy Applications.
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212ISSUES
213Here are the issues associated with IaaS:
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215Compatibility with Legacy Security Vulnerabilities
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217Virtual Machine Sprawl
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219Robustness of VM-level Isolation
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221Data Erase Practices
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223CHARACTERISTICS
224Here are the characteristics of IaaS service model:
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226Virtual machines with pre-installed software.
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228Virtual machines with pre-installed Operating Systems such as windows, Linux, and Solaris.
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230On-demand availability of resources.
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232Allows to store copies of particular data in different locations.
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234The computing resources can be easily scaled up and down.
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236Platform as a Service(PaaS)
237PaaS offers the run time environment for applications. It also offers development & deployment tools, required to develop applications. PaaS has a feature of point-and-click tools that enables non-developers to create web applications.
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239The following diagram shows how PaaS offers an API and development tools to the developers and how it helps the end user to access business applications.
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242BENEFITS
243Following are the benefits of PaaS model:
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245Lower administrative overhead
246
247Lower total cost of ownership
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249Scalable Solutions
250
251More current system software
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253ISSUES
254Like SaaS, PaaS also place significant burdens on consumer's browsers to maintain reliable and secure connections to the provider systems. Therefore, PaaS shares many of the issues of SaaS. However, there are some specific issues associated with PaaS as listed below:
255
256Lack of portability between PaaS clouds
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258Event Based Processor Scheduling
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260Security Engineering of PaaS applications
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262Software as a Service (SaaS)
263Software as a Service(SaaS) model allows to provide software applications as a service to the end users. It refers to a software that is deployed on a hosted service and is accessible via internet. There are several SaaS applications. Some of them are listed below:
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265Billing and Invoicing System
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267Customer Relationship Management (CRM) applications
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269Help Desk Applications
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271Human Resource (HR) Solutions
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273CHARACTERISTICS
274Here are the characteristics of SaaS service model:
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276SaaS makes the software available over the internet.
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278The Software are maintained by the vendor rather than where they are running.
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280The license to the software may be subscription based or usage based. And it is billed on recurring basis.
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282SaaS applications are cost effective since they do not require any maintenance at end user side.
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284They are available on demand.
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286They can be scaled up or down on demand.
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288They are automatically upgraded and updated.
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290SaaS offers share data model. Therefore multiple users can share single instance of infrastructure. It is not required to hard code the functionality for individual users.
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292All users are running same version of the software.
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294BENEFITS
295Using SaaS has proved to be beneficial in term of scalability, efficiency, performance and much more. Some of the benefits are listed below:
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297Modest Software Tools
298
299Efficient use of Software Licenses
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301Centralized Management & Data
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303Platfrom responsibilities managed by provider
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305Multitenant solutions.
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307ISSUES
308There are several issues associated with SaaS. Some of them are listed below:
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310Browser based risks
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312Network dependence
313
314Lack of portability between SaaS clouds
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316Identity as a Service(IDaaS)
317OVERVIEW
318Employees in a company require to login to system to perform various tasks. These systems may be based on local server or cloud based. Following are the problems that an employee might face:
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320Remembering different username and password combinations for accessing multiple servers.
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322If an employee leaves the company, It's required to ensure that each of the user's account has been disabled. This increases workload on IT staff.
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324To solve above problems, a new technique emerged which is known as Identity as a Service (IDaaS).
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326IDaaS offers management of identity (information) as a digital entity. This identity can be used during electronic transactions.
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328IDENTITY
329Identity refers to set of attributes associated with something and make it recognizable. All objects may have some same attributes but their identity can not be the same. This unique identity is assigned through unique identification attribute.
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331There are several identity services that have been deployed to validate services such as validating web sites, transactions, transaction participants, client etc. Identity as a Service may include the following:
332Directory Services
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334Federated Services
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336Registration
337
338Authentication Services
339
340Risk and Event monitoring
341
342Single sign-on services
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344Identity and Profile management
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346SINGLE SIGN-ON (SSO)
347To solve the problem of using different username & password combination for different servers, companies now employ Single Sign-On software, which allows the user to login only one time and manages the user's access to other systems.
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349SSO has single authentication server, managing multiple access to other systems, as shown in the following diagram:
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352SSO WORKING
353There are several implementations of SSO. Here, we discuss the common working of SSO:
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356Following steps explain the working of Single Sign-On software:
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358User logs into the authentication server using a username and password.
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360The authentication server returns the user's ticket.
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362User sends the ticket to intranet server.
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364Intranet server sends the ticket to the authentication server.
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366Authentication server sends the user's security credentials for that server back to the intranet server.
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368If an employee leaves the company, then it just required to disable the user at the authentication server, which in turn disable the user's access to all the systems.
369FEDERATED IDENTITY MANAGEMENT(FIDM)
370FIDM describes the technologies and protocols that enable a user to package security credentials across security domains. It uses Security Markup Language (SAML) to package a user's security credentials as shown in the following diagram:
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373OPENID
374It offers users to login multiple websites with single account. Google, Yahoo!, Flickr, MySpace, WordPress.com are some of the companies that support OpenID.
375
376BENEFITS
377Increased site conversation rates.
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379Access to greater user profile content.
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381Fewer problems with lost passwords.
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383Ease of content integration into social networking sites.
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385Network as a Service(NaaS)
386OVERVIEW
387Networks as a Service allows us to access to network infrastructure directly and securely. NaaS makes it possible to deploy custom routing protocols.
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389NaaS uses virtualized network infrastructure to provide network services to the consumer. It is the responsibility of NaaS provider to maintain and manage the network resources, which decreases the workload from the consumer. Moreover, NaaS offers network as a utility.
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391NaaS is also based on pay-per-use model.
392HOW NAAS IS DELIVERED?
393To use NaaS model, the consumer is required to logon to the web portal, where he can get on line API. Here, the consumer can customize the route.
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395In turn, consumer has to pay for the capacity used. It is also possible to turn off the capacity at any time.
396
397MOBILE NAAS
398Mobile NaaS offers more efficient and flexible control over mobile devices. It uses virtualization to simplify the architecture to create more efficient processes.
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400Following diagram shows the Mobile NaaS service elements:
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403NAAS BENEFITS
404NaaS offers a number of benefits, some of the are discussed below:
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406Independence
407
408Analytics
409
410Resilience
411
412Ease of Adding new Service Elements
413
414Isolation of customer traffic
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416Support Models
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418Cloud Management Tasks
419Cloud Management involves a number of tasks to be performed by the cloud provider to ensure efficient use of cloud resources. Here, we will discuss some of these tasks:
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421Audit System Backups
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423System's Data Flow Management
424
425Ensuring no Vendor Lock-in
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427Provider's security procedures
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429Monitor Capacity Planning and Scaling Capabilities
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431Monitor Audit-Log Use
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433Solution testing and Validation
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435Cloud Data Storage
436Cloud Storage is a service that allows to save data on offsite storage system managed by third party and is made accessible by a web services API.
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438Storage Devices
439Storage devices can be broadly classified into two categories:
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441Block Storage Devices
442
443File Storage Devices
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445BLOCK STORAGE DEVICES
446Block Storage Devices offers the raw storage to the clients. This raw storage can be partitioned to create volumes.
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448FILE STORAGE DEVICES
449File Storage Devices offers storage to clients in form of files, maintaining its own file system. This storage is in the form of Network Attached Storage (NAS).
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451Cloud Storage Classes
452Cloud Storage can be broadly classified into two categories:
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454Unmanaged Cloud Storage
455
456Managed Cloud Storage
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458UNMANAGED CLOUD STORAGE
459Unmanaged Cloud Storage means that the storage is preconfigured for the consumer. The consumer can not format nor the consumer can install own file system or change drive properties.
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461MANAGED CLOUD STORAGE
462Managed Cloud Storage offers online storage space on demand. Managed cloud storage system presents what appears to the user to be a raw disk that the user can partition and format.
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464Creating Cloud Storage System
465The cloud storage system stores multiple copes of data on multiple servers and in multiple locations. If one system fails then it only requires to change the pointer to stored object's location.
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467To aggregate storage assets into cloud storage systems, the cloud provider can use storage virtualization software, StorageGRID. It creates a virtualization layer that fetches storage from different storage devices into a single management system. It can also manage data from CIFS and NFS file system over the Internet. The following diagram shows how SystemGRID virtualizes the storage into storage clouds:
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470Virtual Storage Containers
471Virtual storage containers offer high performance cloud storage systems. Logical Unit Number (LNU) of device, files and other objects are created in virtual storage containers. Following diagram shows a virtual storage container, defining a cloud storage domain:
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474Challenges
475Storing the data in cloud is not that simple task. Apart from its flexibility and convenience, it also has several challenges faced by the consumers. The consumers require ability to:
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477Provision additional storage on demand.
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479Know and restrict the physical location of the stored data.
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481Verify how data was erased?
482
483Have access to a documented process for surely disposing of data storage hardware.
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485Administrator access control over data.
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487Virtualization Concept
488Creating a virtual machine over existing operating system and hardware is referred as Hardware Virtualization. Virtual Machines provide an environment that is logically separated from the underlying hardware.
489
490The machine on which the virtual machine is created is known as host machine and virtual machine is referred as a guest machine. This virtual machine is managed by a software or firmware which is known as hypervisor.
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492Hypervisor
493Hypervisor is a firmware or low level program that acts as a Virtual Machine Manager. There are two types of hypervisor:
494
495Type 1 hypervisor runs on bare system. LynxSecure, RTS Hypervisor, Oracle VM, Sun xVM Server, VirtualLogic VLX are examples of Type 1 hypervisor. The following diagram shows the Type 1 hypervisor.
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497cloud_computing Tutorial
498The type1 hypervisor does not have any host operating system because they are installed on a bare system.
499Type 2 hypervisor is a software interface that emulates the devices with which a system normally interacts. Containers, KVM, Microsoft Hyper V, VMWare Fusion, Virtual Server 2005 R2, Windows Virtual PC and VMWare workstation 6.0 are examples of Type 2 hypervisor. The following diagram shows the Type 2 hypervisor.
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502Types of Hardware Virtualization
503Here are the three types of hardware virtualization:
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505Full Virtualization
506
507Emulation Virtualization
508
509Paravirtualization
510
511Full Virtualization
512In Full Virtualization, the underlying hardware is completely simulated. Guest software do not require any modification to run.
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515Emulation Virtualization
516In Emulation, the virtual machine simulates the hardware and hence become independent of the it. In this, the guest operating system does not require modification.
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519Paravirtualization
520In Paravirtualization, the hardware is not simulated. The guest software run their own isolated domains.
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523VMware vSphere is highly developed infrastructure that offers a management infrastructure framework for virtualization. It virtualizes the system, storage and networking hardware.
524Securing the Cloud
525Security in cloud computing is a major concern. Data in cloud should be stored in encrypted form. To restrict client from direct accessing the shared data, proxy and brokerage services should be employed.
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527Security Planning
528Before deploying a particular resource to cloud, one should need to analyze several attributes about the resource such as:
529
530Select which resources, he is going to move to cloud and analyze its sensitivity to risk.
531
532Consider cloud service models such as IaaS, PaaS, and SaaS. These models require consumer to be responsible for security at different level of service.
533
534Consider which cloud type such as public, private, community or hybrid.
535
536Understand the cloud service provider's system that how data is transferred, where it is stored and how to move data into and out of cloud.
537
538Mainly the risk in cloud deployment depends upon the service models and cloud types.
539Understanding Security of Cloud
540Security Boundaries
541A particular service model defines the boundary between the responsibilities of service provider and consumer. Cloud Security Alliance (CSA) stack model defines the boundaries between each service model and shows how different functional units relate to each other. The following diagram shows the CSA stack model:
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544KEY POINTS TO CSA MODEL:
545IaaS is the most basic level of service with PaaS and SaaS next two above level of service.
546
547Moving upwards each of the service inherits capabilities and security concerns of the model beneath.
548
549IaaS provides the infrastructure, PaaS provides platfrom development environment and SaaS provides operating environment.
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551IaaS has the least level of integrated functionalities and integrated security while SaaS has the most.
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553This model describes the security boundaries at which cloud service provider's responsibility ends and the consumer's responsibilities begin.
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555Any security mechanism below the security boundary must be built into the system and above should me maintained by the consumer.
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557Although each service model has security mechanism but security needs also depends upon where these services are located, in private, public, hybrid or community cloud.
558Understanding Data Security
559Since all the data is transferred using internet, therefore, data security is of major concern in cloud. Here are key mechanisms for protecting data mechanisms listed below:
560
561Access Control
562
563Auditing
564
565Authentication
566
567Authorization
568
569All of the service model must should incorporate security mechanism operating in all above mentioned areas.
570
571Isolated Access to Data
572Since data stored in the cloud can be accessed from anywhere, therefore, in order to protect the data, we must have a mechanism to protect it from the client direct access.
573
574Brokered Cloud Storage Access is one of the approach for isolating the storage in cloud. In this approach two services are created:
575
576A broker with full access to storage but no access to client.
577
578A proxy with no access to storage but access to both client and broker.
579
580working of Brokered Cloud Storage Access system
581When the client issue request to access data:
582
583The client data request goes to proxy's external service interface.
584
585The proxy forwards the request to the broker.
586
587The broker requests the data from cloud storage system.
588
589The cloud storage system returns the data to the broker.
590
591The broker returns the data to proxy.
592
593Finally the proxy sends the data to the client.
594
595All of the above steps are shown in the following diagram:
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598Encryption
599Encryption helps to protect data from being compromised. It protects data that is being transferred as well as data stored in the cloud. Although encryption helps to protect data from any unauthorized access, it does not prevent from data loss.
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601Cloud Computing Operations
602Overview
603Cloud computing operation refers to delivering superior cloud service. Today cloud computing operations have become very popular and widely employed by many of the organizations just because, it allows to perform all business operations over the internet.
604
605These operations can be performed using a web application or mobile based applications. There are a number of operations that are performed in cloud, some of them are shown in the following diagram:
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608Managing Cloud Operations
609There are several ways to manage day to day cloud operations, as shown in the following diagram:
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612Always employ right tools and resources to perform any function in the cloud.
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614Things should be done at right time and at right cost.
615
616Selecting an appropriate resource is mandatory for operation management.
617
618The process should be standardized and automated to avoid repetitive tasks.
619
620Using efficient process will eliminate the waste and redundancy.
621
622One should maintain the quality of service to avoid re-work later.
623
624Cloud Applications
625Cloud Computing has its applications in almost all the fields such as business, entertainment, data storage, social networking, management, entertainment, education, art and global positioning system etc. Some of the widely famous cloud computing applications are discusses here in this tutorial:
626
627Business Applications
628Cloud computing has made business more collaborative and easy by incorporating various apps such as MailChimp, Chatter, Google Apps for business, and Quickbooks.
629
630SN	Application Description
6311	MailChimp
632It offers an email publishing platfrom. It is widely employed by the businesses to design and send their email campaigns.
6332	Chatter
634Chatter app helps the employee to share important information about organization in real time. One can get the instant feed regarding any issue.
6353	Google Apps for Business
636Google offers creating text documents, spreadsheets, presentations etc. on Google Docs which allows the business users to share them in collaborating manner.
6374	Quickbooks
638It offers online accounting solutions for a business. It helps in monitoring cash flow, creating VAT returns and creating business reports.
639Data Storage and Backup
640Box.com, Mozy, Joukuu are the applications, offering data storage and backup services in cloud.
641
642SN	Application Description
6431	Box.com
644Box.com offers drag and drop service for files. It just required to drop the files into Box and access from anywhere.
6452	Mozy
646Mozy offers online backup service for files during a data loss.
6473	Joukuu
648Joukuu is a web based interface. It allows to display a single list of contents for files stored to Google Docs, Box.net and Dropbox.
649Management Applications
650There are apps available for management task such as time tracking, organizing notes. Applications performing such tasks are discussed below:
651
652SN	Application Description
6531	Toggl
654It helps in tracking time period assigned to a particular project.
6552	Evernote
656Evernote is an application that organizes the sticky notes and even can read the text from images which helps the user to locate the notes easily.
6573	Outright
658It is an accounting app. It helps to track income, expenses, profits and losses in real time.
659Social Applications
660There are several social networking services providing websites such as Facebook, Twitter etc.
661
662SN	Application Description
6631	Facebook
664Facebook offer social networking service. One can share photos, videos, files, status and much more.
6652	Twitter
666Twitter helps to interact directly with the public. Once can follow any celebrity, organization and any person who is on twitter and can have latest updates regarding the same.
667Entertainment Applications
668SN	Application Description
6691	Audiobox.fm
670It offers streaming service i.e. music can be stored online and can be played from cloud using service's own media player.
671Art Applications
672SN	Application Description
6731	Moo
674It offers art services such as designing and printing business cards, poscards and minicards.
675Cloud Providers
676Various Cloud Computing platforms are available today. The following table contains the popular Cloud Computing platforms:
677
678SN	Platforms Description
6791	Salesforce.com
680This is a Force.com development platfrom. This provide a simple user interface and lets users log in, build an app and push it in the cloud.
6812	Appistry
682The Appistry's CloudQ platform is efficient in delivering a run-time application platform. This platform is very useful to create scalable and service oriented applications.
6833	AppScale
684The AppScale is an open source platform for Google App Engine applications.
6854	AT&T
686The AT&T allows access to virtual servers and manages the virtualization AT&T The AT&T allows access to virtual servers and manages the virtualization infrastructure. This virtualization infrastructure includes network, server and storage.
6875	Engine Yard
688The Engine Yard is a Rails Application cloud computing platform.
6896	Enomaly
690Enomaly's provides the Infrastructure-as-a-Service platform.
6917	FlexiScale
692The FlexiScale offers a cloud computing platform that allows flexible, scalable and automated cloud infrastructure.
6938	GCloud3
694The GCloud3 offers private cloud solution in its gPlatform.
6959	Gizmox
696The Gizmox Visual WebGUI platfrom is best suited for developing new web apps and modernize the legacy apps based on ASP.net, DHTML etc.
69710	GoGrid
698The GoGrid platform allows the users to deploy web and database cloud services.
69911	Google
700The Google's App Engine, let the users build, run and maintain their applications on Google's infrastructure.
70112	LongJump
702The LongJump offers a Business Application Platform, a platform-as-a-Service (PaaS).
70313	Microsoft
704The Microsoft's Windows Azure is a cloud computing platform, offering an environment to create cloud apps and services.
70514	OrangeScape
706OrangeScape is offers a Platform-as-a-Service (Paas) for non programmers. Building an app is as easy as spreadsheet.
70715	RackSpace
708The RackSpace provide servers-on-demand via a cloud-driven platfrom of virtualized servers.
70916	Amazon EC2
710The Amazon EC2 (Elastic Compute Cloud) lets the users configure and control computing resources while running them on Amazon's environment.
711Cloud Computing Challenges
712Cloud computing, an emergence technology, have placed many challenges in different aspects. Some of these are shown in the following diagram:
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715Security & Privacy
716Security and Privacy of information is the biggest challenge to cloud computing. To get out of security and privacy issues can be over come by employing encryption, security hardware and security applications.
717
718Portability
719This is another challenge to cloud computing that applications should easily be migrated form one cloud provider to another. There should not be vendor-lock in. However, it is not yet made possible because each of the cloud provider use different standard languages for their platforms.
720
721Interoperability
722Application on one platform should be able to incorporate services from other platfrom. It is made possible via web services. But this writing such web services is very complex.
723
724Computing Performance
725To deliver data intensive applications on cloud requires high network bandwidth which result in high cost. If done at low bandwidth, then it does not meet the required computing performance of cloud application.
726
727Reliability and Availability
728It is necessary for cloud systems to be reliable and robust because most of the business are now becoming dependent on services provided by third party.
729
730Mobile Cloud Computing
731Cloud Computing offers such smartphones that have rich internet media experience and require less processing, less power. In term of Mobile Cloud Computing, processing is done in cloud, data is stored in cloud. And the mobile devices serve as a media for display.
732
733Today smartphones are employed with rich cloud services by integrating applications that consume web services. These web services are deployed in cloud.
734
735There are several Smartphone operating systems available such as Google's Android, Apple's iOS, RIM BlackBerry, Symbian, and Windows Mobile Phone. Each of these platform support third party applications that are deployed in cloud.
736
737Architecture
738MCC includes four types of cloud resources:
739
740Distant mobile cloud
741
742Distant immobile cloud
743
744Proximate mobile computing entities
745
746Proximate immobile computing entities
747
748Hybrid
749
750The following diagram shows the framework for mobile cloud computing architecture:
751
752cloud_computing Tutorial
753Issues
754Despite of having significant development in field of mobile computing, there still exists many issues:
755
756Emergency efficient transmission
757There should be a frequent transmission of information between cloud and the mobile devices.
758
759Architectural Issues
760Mobile cloud computing is required to make architectural neutral because of heterogeneous environment.
761
762Live VM migration
763It is challenging to migrate an application which is resource-intensive to cloud and to execute it via. Virtual Machine .
764
765Mobile Communication Congestion
766Due to continuous increase demand for mobile cloud services, the workload to enable smooth communication between cloud and mobile devices has been increased.
767
768Security and Privacy
769This is one of the major issue because mobile users share their personal information over the cloud.