7. Private Cloud: just another name for a data
center?
• resides on a private network that runs on (part of) a
data center that is exclusively used by one
organization;
• owned, managed and run by either the organization
itself, a third party or a combination of the two;
• supports the organization’s business objectives in an
economic sound way;
• high security (compliance with legislation and
regulations).
8. Public Cloud
• Delivery of off-site services over the internet
• Sharing of resources; ‘multi-tenancy’ means a lower
level of security and privacy
• Aimed at a wide audience
• Compelling services like email and social media
• Enables social networking and collaboration
9. Community Cloud
• A type of shared private cloud
• Delivers services to a specific group of organizations and/or
individuals that share a common goal
• Sharing of data, platforms and applications
• Sharing of capital expenditure for otherwise (too) expensive
facilities
• 24/7 access and support
• Shared service and support contracts
• Economics of scale
Examples: regional or national educational or research institutes,
community centers, etc.
10. Hybrid Cloud
• A mix of the above models; combining several Private
and Public Cloud solutions from several providers into
one (virtual) IT infrastructure
• Choosing specific services for either Private or Public
Cloud suitability is balancing:
• security
• privacy
• compliance versus price
11. 1.1.3 Cloud Service Models
• Software as a Service (SaaS)
• The customer does not need to worry about the
development and management of applications.
• Platform as a Service (PaaS)
• Not owning a computer platform, but being able to use it
‘on demand’ can save costs in ownership, management and
maintenance.
• Infrastructure as a Service (IaaS)
• Rental of physical or virtual hardware like storage, servers
or internet connectivity.
12. SaaS
• Key characteristics:
• Software hosted offsite
• Software on demand
• Software package
• No modification of the software
• Plug-in software: external software used with internal
applications (Hybrid Cloud)
• Vendor with advanced technical knowledge
• User entangled with vendor
• Examples: CRM, ERP, Billing and invoicing, Web
Hosting, Etc.
13. PaaS
• Key characteristics:
• Mostly used for remote application development
• Remote application support
• Platform may have special features
• Low development costs
• Variants
• Environment for software development
• Hosting environment for applications
• Online storage
14. IaaS
• The background of IaaS can be found in the merger
between IT and Telecom infrastructure and services in the
past decade
• Key characteristics:
• Dynamic scaling
• Desktop virtualization
• Policy-based services
• Examples of IaaS are hosting services supporting e-
commerce, web hosting services that include broadband
connections and storage.