KEMBAR78
Introduction to Cloud Computing | PPTX
What is Cloud Computing? 
• Cloud Computing is a general term used to describe a new 
class of network based computing that takes place over the 
Internet, 
– basically a step on from Utility Computing 
– a collection/group of integrated and networked hardware, 
software and Internet infrastructure (called a platform). 
– Using the Internet for communication and transport 
provides hardware, software and networking services to 
clients 
• These platforms hide the complexity and details of the 
underlying infrastructure from users and applications by 
providing very simple graphical interface or API (Applications 
Programming Interface). 
1
What is Cloud Computing? 
• In addition, the platform provides on demand 
services, that are always on, anywhere, 
anytime and any place. 
• Pay for use and as needed, elastic 
– scale up and down in capacity and functionalities 
• The hardware and software services are 
available to 
– general public, enterprises, corporations and 
businesses markets 
2
Cloud Summary 
• Cloud computing is an umbrella term used to refer to 
Internet based development and services 
• A number of characteristics define cloud data, 
applications services and infrastructure: 
– Remotely hosted: Services or data are hosted on remote 
infrastructure. 
– Ubiquitous: Services or data are available from anywhere. 
– Commodified: The result is a utility computing model 
similar to traditional that of traditional utilities, like gas 
and electricity - you pay for what you would want! 
3
Cloud Architecture 
4
What is Cloud Computing 
• Shared pool of configurable computing resources 
• On-demand network access 
• Provisioned by the Service Provider 
Adopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim 5 
Grance
Cloud Computing Characteristics 
6 
Common Characteristics: 
Massive Scale Resilient Computing 
Virtualization Service Orientation 
Low Cost Software 
Advanced Security 
Homogeneity 
Geographic Distribution 
Essential Characteristics: 
On Demand Self-Service 
Broad Network Access Rapid Elasticity 
Resource Pooling 
Measured Service 
Adopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim 
Grance
Cloud Service Models 
7 
Software as a 
Service (SaaS) 
Platform as a 
Service (PaaS) 
Infrastructure as a 
Service (IaaS) 
SalesForce CRM 
LotusLive 
Google 
App 
Engine 
Adopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim 
Grance
SaaS Maturity Model 
8 
Level 1: Ad-Hoc/Custom – 
One Instance per customer 
Level 2: Configurable per 
customer 
Level 3: configurable & 
Multi-Tenant-Efficient 
Level 4: Scalable, Configurable 
& Multi-Tenant-Efficient 
Source: Frederick Chong and Gianpaolo Carraro, “Architectures Strategies for Catching the Long Tail”
Different Cloud Computing Layers 
Application Service 
(SaaS) 
Application Platform 
Server Platform 
MS Live/ExchangeLabs, IBM, 
Google Apps; Salesforce.com 
Quicken Online, Zoho, Cisco 
Google App Engine, Mosso, 
Force.com, Engine Yard, 
Facebook, Heroku, AWS 
3Tera, EC2, SliceHost, 
GoGrid, RightScale, Linode 
Storage Platform Amazon S3, Dell, Apple, ... 
9
Cloud Computing Service Layers 
Services 
Application 
Development 
Platform 
Storage 
Hosting 
Description 
Services – Complete business services such as 
PayPal, OpenID, OAuth, Google Maps, Alexa 
Services 
Application 
Focused 
Infrastructure 
Focused 
Application – Cloud based software that eliminates 
the need for local installation such as Google Apps, 
Microsoft Online 
Development – Software development platforms used 
to build custom cloud based applications (PAAS & 
SAAS) such as SalesForce 
Platform – Cloud based platforms, typically provided 
using virtualization, such as Amazon ECC, Sun Grid 
Storage – Data storage or cloud based NAS such 
as CTERA, iDisk, CloudNAS 
Hosting – Physical data centers such as those run 
by IBM, HP, NaviSite, etc. 
10
Basic Cloud Characteristics 
• The “no-need-to-know” in terms of the underlying 
details of infrastructure, applications interface with 
the infrastructure via the APIs. 
• The “flexibility and elasticity” allows these systems 
to scale up and down at will 
– utilising the resources of all kinds 
• CPU, storage, server capacity, load balancing, and databases 
• The “pay as much as used and needed” type of 
utility computing and the “always on!, anywhere 
and any place” type of network-based computing. 
11
Basic Cloud Characteristics 
• Cloud are transparent to users and 
applications, they can be built in multiple 
ways 
– branded products, proprietary open source, 
hardware or software, or just off-the-shelf PCs. 
• In general, they are built on clusters of PC 
servers and off-the-shelf components plus 
Open Source software combined with in-house 
applications and/or system software. 
12
Software as a Service (SaaS) 
• SaaS is a model of software deployment where an 
application is hosted as a service provided to 
customers across the Internet. 
• Saas alleviates the burden of software 
maintenance/support 
– but users relinquish control over software versions and 
requirements. 
• Terms that are used in this sphere include 
– Platform as a Service (PaaS) and 
– Infrastructure as a Service (IaaS) 
13
Virtualization 
• Virtual workspaces: 
– An abstraction of an execution environment that can be made 
dynamically available to authorized clients by using well-defined 
protocols, 
– Resource quota (e.g. CPU, memory share), 
– Software configuration (e.g. O/S, provided services). 
• Implement on Virtual Machines (VMs): 
– Abstraction of a physical host machine, 
– Hypervisor intercepts and emulates instructions from VMs, and allows 
management of VMs, 
– VMWare, Xen, etc. 
• Provide infrastructure API: 
App App App 
OS 
OS OS 
Hypervisor 
– Plug-ins to hardware/support structures Hardware 
Virtualized Stack
Virtual Machines 
• VM technology allows multiple virtual 
machines to run on a single physical machine. 
App App App App App 
Virtual Machine Monitor (VMM) / Hypervisor 
Hardware 
Guest OS 
(Linux) 
Guest OS 
(NetBSD) 
Guest OS 
(Windows) 
VM VM VM 
Xen 
VMWare 
UML 
Denali 
etc. 
Performance: Para-virtualization (e.g. Xen) is very close to raw physical 
performance! 
15
What is the purpose and benefits? 
• Cloud computing enables companies and 
applications, which are system infrastructure 
dependent, to be infrastructure-less. 
• By using the Cloud infrastructure on “pay as used 
and on demand”, all of us can save in capital and 
operational investment! 
• Clients can: 
– Put their data on the platform instead of on their own 
desktop PCs and/or on their own servers. 
– They can put their applications on the cloud and use the 
servers within the cloud to do processing and data 
manipulations etc. 
17
Cloud-Sourcing 
• Why is it becoming a Big Deal: 
– Using high-scale/low-cost providers, 
– Any time/place access via web browser, 
– Rapid scalability; incremental cost and load sharing, 
– Can forget need to focus on local IT. 
• Concerns: 
– Performance, reliability, and SLAs, 
– Control of data, and service parameters, 
– Application features and choices, 
– Interaction between Cloud providers, 
– No standard API – mix of SOAP and REST! 
– Privacy, security, compliance, trust… 
18
Some Commercial Cloud Offerings 
19
Cloud Taxonomy 
20
Cloud Storage 
• Several large Web companies are now exploiting the 
fact that they have data storage capacity that can be 
hired out to others. 
– allows data stored remotely to be temporarily cached on 
desktop computers, mobile phones or other Internet-linked 
devices. 
• Amazon’s Elastic Compute Cloud (EC2) and Simple 
Storage Solution (S3) are well known examples 
– Mechanical Turk 
21
Amazon Simple Storage Service (S3) 
• Unlimited Storage. 
• Pay for what you use: 
– $0.20 per GByte of data transferred, 
– $0.15 per GByte-Month for storage used, 
– Second Life Update: 
• 1TBytes, 40,000 downloads in 24 hours - $200, 
22
Utility Computing – EC2 
• Amazon Elastic Compute Cloud (EC2): 
– Elastic, marshal 1 to 100+ PCs via WS, 
– Machine Specs…, 
– Fairly cheap! 
• Powered by Xen – a Virtual Machine: 
– Different from Vmware and VPC as uses “para-virtualization” where 
the guest OS is modified to use special hyper-calls: 
– Hardware contributions by Intel (VT-x/Vanderpool) and AMD (AMD-V). 
– Supports “Live Migration” of a virtual machine between hosts. 
• Linux, Windows, OpenSolaris 
• Management Console/AP 
23
EC2 – The Basics 
• Load your image onto S3 and register it. 
• Boot your image from the Web Service. 
• Open up required ports for your image. 
• Connect to your image through SSH. 
• Execute you application… 
24
Opportunities and Challenges 
• The use of the cloud provides a number of 
opportunities: 
– It enables services to be used without any understanding 
of their infrastructure. 
– Cloud computing works using economies of scale: 
• It potentially lowers the outlay expense for start up companies, as 
they would no longer need to buy their own software or servers. 
• Cost would be by on-demand pricing. 
• Vendors and Service providers claim costs by establishing an 
ongoing revenue stream. 
– Data and services are stored remotely but accessible from 
“anywhere”. 
25
Opportunities and Challenges 
• In parallel there has been backlash against cloud computing: 
– Use of cloud computing means dependence on others and that could 
possibly limit flexibility and innovation: 
• The others are likely become the bigger Internet companies like Google 
and IBM, who may monopolise the market. 
• Some argue that this use of supercomputers is a return to the time of 
mainframe computing that the PC was a reaction against. 
– Security could prove to be a big issue: 
• It is still unclear how safe out-sourced data is and when using these 
services ownership of data is not always clear. 
– There are also issues relating to policy and access: 
• If your data is stored abroad whose policy do you adhere to? 
• What happens if the remote server goes down? 
• How will you then access files? 
• There have been cases of users being locked out of accounts and losing 
access to data. 
26
Advantages of Cloud Computing 
• Lower computer costs: 
– You do not need a high-powered and high-priced computer 
to run cloud computing's web-based applications. 
– Since applications run in the cloud, not on the desktop PC, 
your desktop PC does not need the processing power or hard 
disk space demanded by traditional desktop software. 
– When you are using web-based applications, your PC can be 
less expensive, with a smaller hard disk, less memory, more 
efficient processor... 
– In fact, your PC in this scenario does not even need a CD or 
DVD drive, as no software programs have to be loaded and 
no document files need to be saved. 
27
Advantages of Cloud Computing 
• Improved performance: 
– With few large programs hogging your computer's 
memory, you will see better performance from your PC. 
– Computers in a cloud computing system boot and run 
faster because they have fewer programs and processes 
loaded into memory… 
• Reduced software costs: 
– Instead of purchasing expensive software applications, you 
can get most of what you need for free-ish! 
• most cloud computing applications today, such as the Google Docs suite. 
– better than paying for similar commercial software 
• which alone may be justification for switching to cloud applications. 
28
Advantages of Cloud Computing 
• Instant software updates: 
– Another advantage to cloud computing is that you are no longer faced 
with choosing between obsolete software and high upgrade costs. 
– When the application is web-based, updates happen automatically 
• available the next time you log into the cloud. 
– When you access a web-based application, you get the latest version 
• without needing to pay for or download an upgrade. 
• Improved document format compatibility. 
– You do not have to worry about the documents you create on your 
machine being compatible with other users' applications or OSes 
– There are potentially no format incompatibilities when everyone is 
sharing documents and applications in the cloud. 
29
Advantages of Cloud Computing 
• Unlimited storage capacity: 
– Cloud computing offers virtually limitless storage. 
– Your computer's current 1 Tbyte hard drive is small 
compared to the hundreds of Pbytes available in the cloud. 
• Increased data reliability: 
– Unlike desktop computing, in which if a hard disk crashes 
and destroy all your valuable data, a computer crashing in 
the cloud should not affect the storage of your data. 
• if your personal computer crashes, all your data is still out there in 
the cloud, still accessible 
– In a world where few individual desktop PC users back up 
their data on a regular basis, cloud computing is a data-safe 
computing platform! 
30
Advantages of Cloud Computing 
• Universal document access: 
– That is not a problem with cloud computing, because you 
do not take your documents with you. 
– Instead, they stay in the cloud, and you can access them 
whenever you have a computer and an Internet connection 
– Documents are instantly available from wherever you are 
• Latest version availability: 
– When you edit a document at home, that edited version is 
what you see when you access the document at work. 
– The cloud always hosts the latest version of your documents 
• as long as you are connected, you are not in danger of having an outdated 
version 
31
Advantages of Cloud Computing 
• Easier group collaboration: 
– Sharing documents leads directly to better collaboration. 
– Many users do this as it is an important advantages of cloud 
computing 
• multiple users can collaborate easily on documents and projects 
• Device independence. 
– You are no longer tethered to a single computer or network. 
– Changes to computers, applications and documents follow 
you through the cloud. 
– Move to a portable device, and your applications and 
documents are still available. 
32
Disadvantages of Cloud Computing 
• Requires a constant Internet connection: 
– Cloud computing is impossible if you cannot connect to the 
Internet. 
– Since you use the Internet to connect to both your 
applications and documents, if you do not have an Internet 
connection you cannot access anything, even your own 
documents. 
– A dead Internet connection means no work and in areas 
where Internet connections are few or inherently 
unreliable, this could be a deal-breaker. 
33
Disadvantages of Cloud Computing 
• Does not work well with low-speed connections: 
– Similarly, a low-speed Internet connection, such as that 
found with dial-up services, makes cloud computing 
painful at best and often impossible. 
– Web-based applications require a lot of bandwidth to 
download, as do large documents. 
• Features might be limited: 
– This situation is bound to change, but today many web-based 
applications simply are not as full-featured as their 
desktop-based applications. 
• For example, you can do a lot more with Microsoft PowerPoint 
than with Google Presentation's web-based offering 
34
Disadvantages of Cloud Computing 
• Can be slow: 
– Even with a fast connection, web-based applications can 
sometimes be slower than accessing a similar software 
program on your desktop PC. 
– Everything about the program, from the interface to the 
current document, has to be sent back and forth from your 
computer to the computers in the cloud. 
– If the cloud servers happen to be backed up at that 
moment, or if the Internet is having a slow day, you would 
not get the instantaneous access you might expect from 
desktop applications. 
35
Disadvantages of Cloud Computing 
• Stored data might not be secure: 
– With cloud computing, all your data is stored on the cloud. 
• The questions is How secure is the cloud? 
– Can unauthorised users gain access to your confidential data? 
• Stored data can be lost: 
– Theoretically, data stored in the cloud is safe, replicated 
across multiple machines. 
– But on the off chance that your data goes missing, you have 
no physical or local backup. 
• Put simply, relying on the cloud puts you at risk if the cloud lets you 
down. 
36
Disadvantages of Cloud Computing 
• HPC Systems: 
– Not clear that you can run compute-intensive HPC 
applications that use MPI/OpenMP! 
– Scheduling is important with this type of application 
• as you want all the VM to be co-located to minimize communication 
latency! 
• General Concerns: 
– Each cloud systems uses different protocols and different APIs 
• may not be possible to run applications between cloud based systems 
– Amazon has created its own DB system (not SQL 92), and 
workflow system (many popular workflow systems out there) 
• so your normal applications will have to be adapted to execute on 
these platforms. 
37
The Future 
• Many of the activities loosely grouped together under cloud 
computing have already been happening and centralised 
computing activity is not a new phenomena 
• Grid Computing was the last research-led centralised 
approach 
• However there are concerns that the mainstream adoption of 
cloud computing could cause many problems for users 
• Many new open source systems appearing that you can install 
and run on your local cluster 
– should be able to run a variety of applications on these systems 
38
39

Introduction to Cloud Computing

  • 1.
    What is CloudComputing? • Cloud Computing is a general term used to describe a new class of network based computing that takes place over the Internet, – basically a step on from Utility Computing – a collection/group of integrated and networked hardware, software and Internet infrastructure (called a platform). – Using the Internet for communication and transport provides hardware, software and networking services to clients • These platforms hide the complexity and details of the underlying infrastructure from users and applications by providing very simple graphical interface or API (Applications Programming Interface). 1
  • 2.
    What is CloudComputing? • In addition, the platform provides on demand services, that are always on, anywhere, anytime and any place. • Pay for use and as needed, elastic – scale up and down in capacity and functionalities • The hardware and software services are available to – general public, enterprises, corporations and businesses markets 2
  • 3.
    Cloud Summary •Cloud computing is an umbrella term used to refer to Internet based development and services • A number of characteristics define cloud data, applications services and infrastructure: – Remotely hosted: Services or data are hosted on remote infrastructure. – Ubiquitous: Services or data are available from anywhere. – Commodified: The result is a utility computing model similar to traditional that of traditional utilities, like gas and electricity - you pay for what you would want! 3
  • 4.
  • 5.
    What is CloudComputing • Shared pool of configurable computing resources • On-demand network access • Provisioned by the Service Provider Adopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim 5 Grance
  • 6.
    Cloud Computing Characteristics 6 Common Characteristics: Massive Scale Resilient Computing Virtualization Service Orientation Low Cost Software Advanced Security Homogeneity Geographic Distribution Essential Characteristics: On Demand Self-Service Broad Network Access Rapid Elasticity Resource Pooling Measured Service Adopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim Grance
  • 7.
    Cloud Service Models 7 Software as a Service (SaaS) Platform as a Service (PaaS) Infrastructure as a Service (IaaS) SalesForce CRM LotusLive Google App Engine Adopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim Grance
  • 8.
    SaaS Maturity Model 8 Level 1: Ad-Hoc/Custom – One Instance per customer Level 2: Configurable per customer Level 3: configurable & Multi-Tenant-Efficient Level 4: Scalable, Configurable & Multi-Tenant-Efficient Source: Frederick Chong and Gianpaolo Carraro, “Architectures Strategies for Catching the Long Tail”
  • 9.
    Different Cloud ComputingLayers Application Service (SaaS) Application Platform Server Platform MS Live/ExchangeLabs, IBM, Google Apps; Salesforce.com Quicken Online, Zoho, Cisco Google App Engine, Mosso, Force.com, Engine Yard, Facebook, Heroku, AWS 3Tera, EC2, SliceHost, GoGrid, RightScale, Linode Storage Platform Amazon S3, Dell, Apple, ... 9
  • 10.
    Cloud Computing ServiceLayers Services Application Development Platform Storage Hosting Description Services – Complete business services such as PayPal, OpenID, OAuth, Google Maps, Alexa Services Application Focused Infrastructure Focused Application – Cloud based software that eliminates the need for local installation such as Google Apps, Microsoft Online Development – Software development platforms used to build custom cloud based applications (PAAS & SAAS) such as SalesForce Platform – Cloud based platforms, typically provided using virtualization, such as Amazon ECC, Sun Grid Storage – Data storage or cloud based NAS such as CTERA, iDisk, CloudNAS Hosting – Physical data centers such as those run by IBM, HP, NaviSite, etc. 10
  • 11.
    Basic Cloud Characteristics • The “no-need-to-know” in terms of the underlying details of infrastructure, applications interface with the infrastructure via the APIs. • The “flexibility and elasticity” allows these systems to scale up and down at will – utilising the resources of all kinds • CPU, storage, server capacity, load balancing, and databases • The “pay as much as used and needed” type of utility computing and the “always on!, anywhere and any place” type of network-based computing. 11
  • 12.
    Basic Cloud Characteristics • Cloud are transparent to users and applications, they can be built in multiple ways – branded products, proprietary open source, hardware or software, or just off-the-shelf PCs. • In general, they are built on clusters of PC servers and off-the-shelf components plus Open Source software combined with in-house applications and/or system software. 12
  • 13.
    Software as aService (SaaS) • SaaS is a model of software deployment where an application is hosted as a service provided to customers across the Internet. • Saas alleviates the burden of software maintenance/support – but users relinquish control over software versions and requirements. • Terms that are used in this sphere include – Platform as a Service (PaaS) and – Infrastructure as a Service (IaaS) 13
  • 14.
    Virtualization • Virtualworkspaces: – An abstraction of an execution environment that can be made dynamically available to authorized clients by using well-defined protocols, – Resource quota (e.g. CPU, memory share), – Software configuration (e.g. O/S, provided services). • Implement on Virtual Machines (VMs): – Abstraction of a physical host machine, – Hypervisor intercepts and emulates instructions from VMs, and allows management of VMs, – VMWare, Xen, etc. • Provide infrastructure API: App App App OS OS OS Hypervisor – Plug-ins to hardware/support structures Hardware Virtualized Stack
  • 15.
    Virtual Machines •VM technology allows multiple virtual machines to run on a single physical machine. App App App App App Virtual Machine Monitor (VMM) / Hypervisor Hardware Guest OS (Linux) Guest OS (NetBSD) Guest OS (Windows) VM VM VM Xen VMWare UML Denali etc. Performance: Para-virtualization (e.g. Xen) is very close to raw physical performance! 15
  • 16.
    What is thepurpose and benefits? • Cloud computing enables companies and applications, which are system infrastructure dependent, to be infrastructure-less. • By using the Cloud infrastructure on “pay as used and on demand”, all of us can save in capital and operational investment! • Clients can: – Put their data on the platform instead of on their own desktop PCs and/or on their own servers. – They can put their applications on the cloud and use the servers within the cloud to do processing and data manipulations etc. 17
  • 17.
    Cloud-Sourcing • Whyis it becoming a Big Deal: – Using high-scale/low-cost providers, – Any time/place access via web browser, – Rapid scalability; incremental cost and load sharing, – Can forget need to focus on local IT. • Concerns: – Performance, reliability, and SLAs, – Control of data, and service parameters, – Application features and choices, – Interaction between Cloud providers, – No standard API – mix of SOAP and REST! – Privacy, security, compliance, trust… 18
  • 18.
  • 19.
  • 20.
    Cloud Storage •Several large Web companies are now exploiting the fact that they have data storage capacity that can be hired out to others. – allows data stored remotely to be temporarily cached on desktop computers, mobile phones or other Internet-linked devices. • Amazon’s Elastic Compute Cloud (EC2) and Simple Storage Solution (S3) are well known examples – Mechanical Turk 21
  • 21.
    Amazon Simple StorageService (S3) • Unlimited Storage. • Pay for what you use: – $0.20 per GByte of data transferred, – $0.15 per GByte-Month for storage used, – Second Life Update: • 1TBytes, 40,000 downloads in 24 hours - $200, 22
  • 22.
    Utility Computing –EC2 • Amazon Elastic Compute Cloud (EC2): – Elastic, marshal 1 to 100+ PCs via WS, – Machine Specs…, – Fairly cheap! • Powered by Xen – a Virtual Machine: – Different from Vmware and VPC as uses “para-virtualization” where the guest OS is modified to use special hyper-calls: – Hardware contributions by Intel (VT-x/Vanderpool) and AMD (AMD-V). – Supports “Live Migration” of a virtual machine between hosts. • Linux, Windows, OpenSolaris • Management Console/AP 23
  • 23.
    EC2 – TheBasics • Load your image onto S3 and register it. • Boot your image from the Web Service. • Open up required ports for your image. • Connect to your image through SSH. • Execute you application… 24
  • 24.
    Opportunities and Challenges • The use of the cloud provides a number of opportunities: – It enables services to be used without any understanding of their infrastructure. – Cloud computing works using economies of scale: • It potentially lowers the outlay expense for start up companies, as they would no longer need to buy their own software or servers. • Cost would be by on-demand pricing. • Vendors and Service providers claim costs by establishing an ongoing revenue stream. – Data and services are stored remotely but accessible from “anywhere”. 25
  • 25.
    Opportunities and Challenges • In parallel there has been backlash against cloud computing: – Use of cloud computing means dependence on others and that could possibly limit flexibility and innovation: • The others are likely become the bigger Internet companies like Google and IBM, who may monopolise the market. • Some argue that this use of supercomputers is a return to the time of mainframe computing that the PC was a reaction against. – Security could prove to be a big issue: • It is still unclear how safe out-sourced data is and when using these services ownership of data is not always clear. – There are also issues relating to policy and access: • If your data is stored abroad whose policy do you adhere to? • What happens if the remote server goes down? • How will you then access files? • There have been cases of users being locked out of accounts and losing access to data. 26
  • 26.
    Advantages of CloudComputing • Lower computer costs: – You do not need a high-powered and high-priced computer to run cloud computing's web-based applications. – Since applications run in the cloud, not on the desktop PC, your desktop PC does not need the processing power or hard disk space demanded by traditional desktop software. – When you are using web-based applications, your PC can be less expensive, with a smaller hard disk, less memory, more efficient processor... – In fact, your PC in this scenario does not even need a CD or DVD drive, as no software programs have to be loaded and no document files need to be saved. 27
  • 27.
    Advantages of CloudComputing • Improved performance: – With few large programs hogging your computer's memory, you will see better performance from your PC. – Computers in a cloud computing system boot and run faster because they have fewer programs and processes loaded into memory… • Reduced software costs: – Instead of purchasing expensive software applications, you can get most of what you need for free-ish! • most cloud computing applications today, such as the Google Docs suite. – better than paying for similar commercial software • which alone may be justification for switching to cloud applications. 28
  • 28.
    Advantages of CloudComputing • Instant software updates: – Another advantage to cloud computing is that you are no longer faced with choosing between obsolete software and high upgrade costs. – When the application is web-based, updates happen automatically • available the next time you log into the cloud. – When you access a web-based application, you get the latest version • without needing to pay for or download an upgrade. • Improved document format compatibility. – You do not have to worry about the documents you create on your machine being compatible with other users' applications or OSes – There are potentially no format incompatibilities when everyone is sharing documents and applications in the cloud. 29
  • 29.
    Advantages of CloudComputing • Unlimited storage capacity: – Cloud computing offers virtually limitless storage. – Your computer's current 1 Tbyte hard drive is small compared to the hundreds of Pbytes available in the cloud. • Increased data reliability: – Unlike desktop computing, in which if a hard disk crashes and destroy all your valuable data, a computer crashing in the cloud should not affect the storage of your data. • if your personal computer crashes, all your data is still out there in the cloud, still accessible – In a world where few individual desktop PC users back up their data on a regular basis, cloud computing is a data-safe computing platform! 30
  • 30.
    Advantages of CloudComputing • Universal document access: – That is not a problem with cloud computing, because you do not take your documents with you. – Instead, they stay in the cloud, and you can access them whenever you have a computer and an Internet connection – Documents are instantly available from wherever you are • Latest version availability: – When you edit a document at home, that edited version is what you see when you access the document at work. – The cloud always hosts the latest version of your documents • as long as you are connected, you are not in danger of having an outdated version 31
  • 31.
    Advantages of CloudComputing • Easier group collaboration: – Sharing documents leads directly to better collaboration. – Many users do this as it is an important advantages of cloud computing • multiple users can collaborate easily on documents and projects • Device independence. – You are no longer tethered to a single computer or network. – Changes to computers, applications and documents follow you through the cloud. – Move to a portable device, and your applications and documents are still available. 32
  • 32.
    Disadvantages of CloudComputing • Requires a constant Internet connection: – Cloud computing is impossible if you cannot connect to the Internet. – Since you use the Internet to connect to both your applications and documents, if you do not have an Internet connection you cannot access anything, even your own documents. – A dead Internet connection means no work and in areas where Internet connections are few or inherently unreliable, this could be a deal-breaker. 33
  • 33.
    Disadvantages of CloudComputing • Does not work well with low-speed connections: – Similarly, a low-speed Internet connection, such as that found with dial-up services, makes cloud computing painful at best and often impossible. – Web-based applications require a lot of bandwidth to download, as do large documents. • Features might be limited: – This situation is bound to change, but today many web-based applications simply are not as full-featured as their desktop-based applications. • For example, you can do a lot more with Microsoft PowerPoint than with Google Presentation's web-based offering 34
  • 34.
    Disadvantages of CloudComputing • Can be slow: – Even with a fast connection, web-based applications can sometimes be slower than accessing a similar software program on your desktop PC. – Everything about the program, from the interface to the current document, has to be sent back and forth from your computer to the computers in the cloud. – If the cloud servers happen to be backed up at that moment, or if the Internet is having a slow day, you would not get the instantaneous access you might expect from desktop applications. 35
  • 35.
    Disadvantages of CloudComputing • Stored data might not be secure: – With cloud computing, all your data is stored on the cloud. • The questions is How secure is the cloud? – Can unauthorised users gain access to your confidential data? • Stored data can be lost: – Theoretically, data stored in the cloud is safe, replicated across multiple machines. – But on the off chance that your data goes missing, you have no physical or local backup. • Put simply, relying on the cloud puts you at risk if the cloud lets you down. 36
  • 36.
    Disadvantages of CloudComputing • HPC Systems: – Not clear that you can run compute-intensive HPC applications that use MPI/OpenMP! – Scheduling is important with this type of application • as you want all the VM to be co-located to minimize communication latency! • General Concerns: – Each cloud systems uses different protocols and different APIs • may not be possible to run applications between cloud based systems – Amazon has created its own DB system (not SQL 92), and workflow system (many popular workflow systems out there) • so your normal applications will have to be adapted to execute on these platforms. 37
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    The Future •Many of the activities loosely grouped together under cloud computing have already been happening and centralised computing activity is not a new phenomena • Grid Computing was the last research-led centralised approach • However there are concerns that the mainstream adoption of cloud computing could cause many problems for users • Many new open source systems appearing that you can install and run on your local cluster – should be able to run a variety of applications on these systems 38
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