Cloud computing is a style of computing in which dynamically scalable and often virtualized resources are provided as a service over the Internet The concept generally incorporates combinations of the following: * infrastructure as a service (IaaS) * platform as a service (PaaS) * software as a service (SaaS) Cloud infrastructure, such as Infrastructure as a service, is the delivery of computer infrastructure, typically a platform virtualization environment, as a service. For example: * Full virtualization (GoGrid, Skytap, iland) * Grid computing (Sun Cloud) * Management (RightScale) * Compute (Amazon Elastic Compute Cloud) * Platform (Force.com) * Storage (Amazon S3, Nirvanix, Rackspace) A cloud platform, such as Platform as a service, the delivery of a computing platform, and/or solution stack as a service, facilitates deployment of applications without the cost and complexity of buying and managing the underlying hardware and software layers A cloud service includes &quot;products, services and solutions that are delivered and consumed in real-time over the Internet&quot;. For example, Web Services (&quot;software system[s] designed to support interoperable machine-to-machine interaction over a network&quot;) which may be accessed by other cloud computing components, software, e.g., Software plus services, or end users directly. Specific examples include: * Identity (OAuth, OpenID) * Integration (Amazon Simple Queue Service) * Payments (Amazon Flexible Payments Service, Google Checkout, PayPal) * Mapping (Google Maps, Yahoo! Maps, MapQuest) * Search (Alexa, Google Custom Search, Yahoo! BOSS) * Video Games (OnLive, Gaikai) * Live chat (LivePerson) * Others (Amazon Mechanical Turk) Cloud architecture, the systems architecture of the software systems involved in the delivery of cloud computing, comprises hardware and software designed by a cloud architect who typically works for a cloud integrator. It typically involves multiple cloud components communicating with each other over application programming interfaces, usually web services. This closely resembles the Unix philosophy of having multiple programs doing one thing well and working together over universal interfaces. Complexity is controlled and the resulting systems are more manageable than their monolithic counterparts. Cloud architecture extends to the client, where web browsers and/or software applications access cloud applications. Cloud storage architecture is loosely coupled, where metadata operations are centralized enabling the data nodes to scale into the hundreds, each independently delivering data to applications or users. Cloud computing types Public cloud Public cloud or external cloud describes cloud computing in the traditional mainstream sense, whereby resources are dynamically provisioned on a fine-grained, self-service basis over the Internet, via web applications/web services, from an off-site third-party provider who shares resources and bills on a fine-grained utility computing basis. Private cloud Private cloud and internal cloud are neologisms that some vendors have recently used to describe offerings that emulate cloud computing on private networks. These (typically virtualisation automation) products claim to &quot;deliver some benefits of cloud computing without the pitfalls&quot;, capitalising on data security, corporate governance, and reliability concerns. They have been criticized on the basis that users &quot;still have to buy, build, and manage them“ and as such do not benefit from lower up-front capital costs and less hands-on management, essentially &quot;[lacking] the economic model that makes cloud computing such an intriguing concept&quot;.While an analyst predicted in 2008 that private cloud networks would be the future of corporate IT, there is some uncertainty whether they are a reality even within the same firm. Analysts also claim that within five years a &quot;huge percentage&quot; of small and medium enterprises will get most of their computing resources from external cloud computing providers as they &quot;will not have economies of scale to make it worth staying in the IT business&quot; or be able to afford private clouds.. Analysts have reported on Platform's view that private clouds are a stepping stone to external clouds, particularly for the financial services, and that future datacenters will look like internal clouds. The term has also been used in the logical rather than physical sense, for example in reference to platform as a service offerings, though such offerings including Microsoft's Azure Services Platform are not available for on-premises deployment. The following are different vendors for these services: for example for Saas :Google Apps,Gmail,Docs and salesforce.com are the services for Paas (Web 2.0 interface, Programmimg API) for Infrastructure (Virtualization,VM Mgmt and deployment,Amazon S3,Open Nebula,Aneka are some of the exapmles.) The key for SaaS is that it is customizable by customers with limited technical support required. Business users have enthusiastically welcomed the resulting flexibility and speed. 1) grid computing - &quot;a form of distributed computing whereby a 'super and virtual computer' is composed of a cluster of networked, loosely coupled computers, acting in concert to perform very large tasks&quot;. 2) utility computing - the &quot;packaging of computing resources, such as computation and storage, as a metered service similar to a traditional public utility such as electricity&quot; and Cloud computing customers do not generally own the physical infrastructure serving as host to the software platform in question. Instead, they avoid capital expenditure by renting usage from a third-party provider. They consume resources as a service and pay only for resources that they use. Many cloud-computing offerings employ the utility computing model, which is analogous to how traditional utility services (such as electricity) are consumed, while others bill on a subscription basis.benefits of this time sharing style approach are low barriers to entry, and other benefits will be covered subsequently The majority of cloud computing infrastructure, as of 2009[update], consists of reliable services delivered through data centers and built on servers with different levels of virtualization technologies. The services are accessible anywhere that provides access to networking infrastructure. Clouds often appear as single points of access for all consumers' computing needs. Commercial offerings are generally expected to meet quality of service (QoS) requirements of customers and typically offer SLAs. Open standards are critical to the growth of cloud computing, and open source software has provided the foundation for many cloud computing implementations.
Grids are usually computer clusters, but more focused on throughput like a computing utility rather than running fewer, tightly-coupled jobs. Often, grids will incorporate heterogeneous collections of computers, possibly distributed geographically, sometimes administered by unrelated organizations. Super Computing:Often clusters are used for primarily computational purposes, rather than handling IO-oriented operations such as web service or databases. For instance, a cluster might support computational simulations of weather or vehicle crashes. The primary distinction within compute clusters is how tightly-coupled the individual nodes are. For instance, a single compute job may require frequent communication among nodes - this implies that the cluster shares a dedicated network, is densely located, and probably has homogenous nodes. This cluster design is usually referred to as Beowulf Cluster. The other extreme is where a compute job uses one or few nodes, and needs little or no inter-node communication. This latter category is sometimes called &quot;Grid&quot; computing. Tightly-coupled compute clusters are designed for work that might traditionally have been called &quot;supercomputing&quot;. Middleware such as MPI (Message Passing Interface) or PVM (Parallel Virtual Machine) permits compute clustering programs to be portable to a wide variety of clusters.
Cloud Computing refers to both the applications delivered as services over the Internet and the hardware and systems software in the datacenters that provide those services. The services themselves have long been referred to as Software as a Service (SaaS), so we use that term. The datacenter hardware and software is what we will call a Cloud.
Buyya et al.
A Cloud is a type of parallel and distributed system consisting of a collection of interconnected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources based on service-level agreements established through negotiation between the service provider and consumers.
The entire stack (hw & sw) is leveraged to the internet
HaaS Amazon S3
IaaS VMWare, Amazon EC2
PaaS Google AppEngine, Mosso, Aneka
Computing becomes a real utility used by all the masses
service providers (web hosting)
The economic aspect become more important (billing, pricing, QoS, SLA)
These are the two main differences from Grid Computing.
Anatomy of a Cloud Social Networks Scientific Computing Amusement CDNs Financial Applications Infrastructure as a Service Platform as a Service Software as a Service Data Centers Clusters Storage Other Grids/Clouds Virtualization VM Management & Deployment Amazon S3, EC2 OpenNebula, Eucalyptus Mosso Web 2.0 Interface Programming API Scripting & Programming Languages Google AppEngine Microsoft Azure Manjrasoft Aneka Google Apps (Gmail, Docs,…) Salesforce.com QoS Metering SLA Negotiation Admission Control Pricing and Billing Accounting Public Cloud Private Cloud
Evolution of Cloud Computing Terms related to Cloud Computing
Biggies Software on demand Grid computing: massive processing Elastic computer: By 2012, the global market for cloud computing will be $95 billion Merryll Linch
You can take it with you Are gadgets important? As wireless technology gets better and cheaper, more and more different kinds of objects will connect directly to the cloud .
They have already used Cloud … Powerset: a start-up that is creating a natural language powerful search. When they need to catalogue the web, they buy cloud services. New York times: to create 11.000 pdfs, they needed to subcontract cloud services Schumacher Group (emergency rooms for hospitals) : almost affected by Katrina hurricane, they was growing quickly but was having problems to create regional offices to support it. Running some systems remotely was the answer. Starbucks: using Salesforce CRM to create the new idea Mystarbucks.com website as a online community. US Olympic Committee: using AT&T service to handle a busy traffic during the games SOGETI: The consultancy company owned by Cap Gemini contracted cloud services from IBM Blue Cloud to a whole-company brainstorming program.
Cloud – Pros … Customer Supplier Flexibility: new needs can be solved quickly. Elasticity: temporary needs can be solved and you can “return” the infrastructure after the pick. New business: Smaller investment Time-to-market: Faster Implementation Synergies: Hardware investment can be spread Economy of scales: Hardware investment can be spread Alliance: Intel, HP e Yahoo Hardware consolidation: Best use of money invested in hardware Global Model: Data centres are distributed around the world, using better conditions: employees, nature, energy, etc… Costs: employees, nature, energy, etc… Smaller, TCO reduction. Geographical Distribution: Better services for disperse companies and easier mobility.
Cloud – Cons … Customer Supplier Lack of cost advantage: Not achieving ROI before turn people sceptical with CC . Strategy: Large databases; critical data; old systems; systems that require specific hardware Migration: Current enterprise apps can't be migrated conveniently. Management: Difficulty of managing cloud applications. Safety: To manage customer data, the identification management must be solved Liability: …… Latency: …… Lack of Service levels agreements: Cloud providers still are not taking accountability for the platforms Putative Risk: Legal, regulatory and business. Can our data be “elsewhere”? Pricing: How it is being charged. Migrate from boxes to services is a lesson to learn. Performance: Data bases can be less quick Challenge: management of resources, over many locations and with various tenants.