This document provides an overview of cloud computing. It defines cloud computing as utilizing virtualization, utility computing, and software/platform/infrastructure as a service. Key aspects covered include how virtualization abstracts logical from physical resources, the benefits of horizontal and vertical scaling, and examples of software (Salesforce, Google Apps), platform (Amazon EC2, vCloud), and infrastructure as a service providers. It warns that while the cloud provides benefits, data security and uptime depend on internet connectivity.

1. A guide to understanding
cloud computing
Jerry Horgan

2. Buzzwords
• Virtualisation
• Cloud Computing
• Utility Computing
• Everything as a Service (?aaS)

3. So what is Cloud Computing?
• Its Virtualisation
• Its Utility Computing
• Its Software as a Service
• Its Platform as a Service
• Its Infrastructure as a Service
• Its ??? as a Service
• Its all about Services

4. So what isn’t Cloud Computing?
• A silver bullet
• 100% reliable - Don’t believe the hype

5. So what is virtualisation?
• It’s the abstraction of logical resources
from physical resources.
– And that means?
– Sizing the logical resources to the service
requirement rather than sizing the physical
resources to the service requirement.

6. Which brings us to Scaling
• Adding capacity to our service
– Promotions, one-off events (short-lived)
– Natural growth
• Horizontal vs Vertical scaling
• Scaling is traditionally vertical
– Vertical doesn’t scale linearly, more exponentially

7. Utility Computing
• Think electricity
• Paying for computing resources
– Pay as you Grow / Go
– Provider worries about the back-end
systems.

8. as a Service
• SaaS
• PaaS
• IaaS
• Depends on your needs or where you
are in your IT application development
cycle

9. Software as a Service (SaaS)
• Provides a virtual environment for you
to deploy a service (application) in.
• Salesforce.com
• Google Apps
• Or your website

10. SalesForce.com
• CRM Based Apps, Email, Call-Center
Knowledge-Base
• €70 per person per month
• http://www.salesforce.com/eu/

11. Google Apps
• Email, Calendar and Office applications
• $50 per person per year
• http://www.google.com/apps/intl/en/business/
– Compare this to a PC, Email Server /
Hosting, and MS Office costs
• Even over 3-5 years

12. SaaS - Apps run in the cloud
• Applications / Documents available from
anywhere
– Work from home or on the road
• You don’t require powerful desktops or
laptops
– Access devices can be much cheaper / smaller

13. Platform as a Service (PaaS)
• Provides a virtual server for you to
configure.
• This can be a Virtual Machine, a Virtual
Private Server (VPS) or some other
cloud service.

14. Amazon - Elastic Cloud
• The numero uno
• http://aws.amazon.com/ec2/

15. vCloud
• VMWares cloud offering
• http://www.vmware.com/products/vcloud/
• http://www.vmware.com/solutions/cloud-computing/

16. Infrastructure as a Service (IaaS)
• Provides a complete network, data
storage and set of servers
– This usually comes from your ISP or Data-
Center provider

17. Is it all out there in the ether?
• Maybe
• Private cloud vs Public cloud
– You can do both
• Virtual private cloud …

18. What tools can I use?
• Vmware ESXi http://www.vmware.com/products/esxi/
• Citrix XEN
http://www.citrix.com/English/ps2/products/product.asp?
contentID=683148
• UEC http://www.ubuntu.com/cloud
• KVM http://www.linux-kvm.org/page/Main_Page
• Hyper-V
http://www.microsoft.com/windowsserver2008/en/us/hyperv-
main.aspx
• VirtualBox http://www.virtualbox.org/

19. Warning!
• How safe is your data in the cloud?
– Data protection, Discovery orders, FoI
• What happens when you loose your
Internet connection?
– Do we need something better than DSL?
• That depends on our uptime requirement