2. what is cloud?
• Cloud computing is a pay-per-use model for enabling
available, convenient, on-demand network access to a shared pool of
configurable computing resources
(e.g., networks, servers, storage, applications, services) that can be rapidly
provisioned and released with minimal management effort or service
provider interaction.
3. history
The Cloud is a term that borrows from telephony Up to the
1990s, data circuits (including those that carried Internet
traffic) were hard-wired between destinations. Then, long-
haul telephone companies began offering VIRTUAL
PRIVATE NETWORK (VPN) service for data
communications. Telephone companies were able to offer
VPN-based services with the same bandwidth as fixed
circuits at a lower cost because they could switch traffic to
thus utilizing their overall network bandwidth more
effectively.
As a result of this arrangement, it was impossible to
determine in advance precisely which paths the traffic
would be routed over.
4. economics
• Cloud computing users can avoid capital
expenditure (CapEx)
• Consumption is usually billed on a resources consumed, like
electricity or subscription (time-based, like a newspaper)
• Other benefits of this time sharing approach shared
infrastructure and costs, low management overhead, and
immediate access to a broad range of applications.
• In general, users can terminate the contract at any time.
7. Clients
consists of computer hardware or computer software that relies on cloud
computing for application delivery, or that is specifically designed for
delivery of cloud services
For example: Mobile Linux based iPhone, Microsoft based - Windows
Mobile
Application :
A cloud application leverages cloud computing in software architecture, often
eliminating the need to install and run the application on the customer's own
computer, thus alleviating the burden of software maintenance, ongoing
operation, and support.
For example: Web applications(Webmail, Face book, Twitter, You Tube)
8. Platform :
A cloud platform delivers a computing platform as a
service, generally consuming cloud infrastructure and
supporting cloud applications.
It facilitates deployment of applications without the cost and
complexity of buying and managing the underlying hardware and
software layers
For example: Solution stacks Java (Google App Engine PHP (Rack
space Cloud Sites) Python Django (Google AppEngine)
Infrastructure : it is the delivery of the computer infrastructure specially
to the platform virtualization environment
9. servers
The servers layer consists of computer hardware and/or computer
software products that are specifically designed for the delivery of
cloud services
For example: Fabric computing (Cisco UCS)
14. Virtualization in the
Cloud
• Enables multiple users to share the same
hardware, but maintain separation based
on data or application owner.
• Management tools are giving you a
“Enterprise View” of virtual environments.
• Virtualization and Cloud Computing allow
you to “fire” applications more rapidly, but
does not improve an organization’s “aim”.
16. The Traditional Server
Concept
• System Administrators often talk about servers
as a whole unit that includes the hardware, the
OS, the storage, and the applications.
• Servers are often referred to by their function
i.e. the Exchange server, the SQL server, the File
server, etc.
• If the File server fills up, or the Exchange server
becomes overtaxed, then the System
Administrators must add in a new server.
17. The Traditional Server
Concept
• Unless there are multiple servers, if a
service experiences a hardware
failure, then the service is down.
• System Admin can implement clusters of
servers to make them more fault tolerant.
However, even clusters have limits on their
scalability, and not all applications work in
a clustered environment
18. The Virtual Server
Concept
• Virtual servers seek to encapsulate the server software away from
the hardware
– This includes the OS, the applications, and the storage for that server.
• Servers end up as mere files stored on a physical box, or in
enterprise storage.
• A virtual server can be serviced by one or more hosts, and one
host may house more than one virtual server.
• Virtual servers can still be referred to by their function i.e. email
server, database server, etc.
• If the environment is built correctly, virtual servers will not be
affected by the loss of a host.
• Hosts may be removed and introduced almost at will to
accommodate maintenance.
19. Cloud computing takes
virtualization to the next
step
• You don’t have to own the hardware
• You “rent” it as needed from a cloud
• There are public clouds
– e.g. Amazon EC2, and now many others
(Microsoft, IBM, Sun, and others ...)
• A company can create a private one
– With more control over security, etc.
20. How Cloud Computing
Works
• Various providers let you create virtual servers
– Set up an account, perhaps just with a credit card
• You create virtual servers ("virtualization")
– Choose the OS and software each "instance" will have
– It will run on a large server farm located somewhere
– You can instantiate more on a few minutes' notice
– You can shut down instances in a minute or so
• They send you a bill for what you use