INTRODUCTION TO CLOUD COMPUTING CEN483 PARALLEL AND DISTRIBUTED SYSTEMS
CLOUD COMPUTING Cloud computing is a model for enabling convenient, ondemand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. *Definition of NIST
CLOUD COMPUTING The term cloud, appears to have its origins in network diagrams that represented the internet, or various parts of it, as schematic clouds. Cloud computing was coined for what happens when applications and services are moved into the internet cloud. More currently though, cloud computing refers to the many different types of services and applications being delivered in the internet cloud, and the fact that, in many cases, the devices used to access these services and applications do not require any special applications.
CHARACTERISTICS On-demand self-service Broad network access Resource pooling Rapid elasticity Measured Service
ON-DEMAND SELF- SERVICE A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service s provider.
BROAD NETWORK ACCESS Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, laptops, and PDAs).
RESOURCE POOLING The provider s computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. There is a sense of location independence in that the customer generally has no control or knowledge over the exact location of the provided resources but may be able to specify location at a higher level of abstraction (e.g., country, state, or datacenter). Examples of resources include storage, processing, memory, network bandwidth, and virtual machines
RAPID ELASTICITY Capabilities can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be purchased in any quantity at any time.
MEASURED SERVICE Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported providing transparency for both the provider and consumer of the utilized service.
SERVICE MODELS Once a cloud is established, how its cloud computing services are deployed in terms of business models can differ depending on requirements.
SERVICE MODELS
SOFTWARE AS A SERVICE (SAAS) Software-as-a-Service provides complete applications to a cloud s end user. It is mainly accessed through a web portal and service oriented architectures based on web service technologies. Credit card or bank account details must be provided to enable the fees for the use of the services to be billed.
SOFTWARE AS A SERVICE (SAAS) The services on the application layer can be seen as an extension of the ASP (application service provider) model, in which an application is run, maintained, and supported by a service vendor. The main differences between the services on the application layer and the classic ASP model are the encapsulation of the application as a service, the dynamic procurement, and billing by units of consumption (pay as you go). However, both models pursue the goal of focusing on core competencies by outsourcing applications.
SOFTWARE AS A SERVICE (SAAS)
SOFTWARE AS A SERVICE (SAAS) Increased speed of deployment Increased user adoption Reduced support requirements Lowered cost of implementation and upgrades
SOFTWARE AS A SERVICE (SAAS)
SOFTWARE AS A SERVICE (SAAS)
PLATFORM AS A SERVICE (PAAS) PaaS comprises the environment for developing and provisioning cloud applications. The principal users of this layer are developers seeking to develop and run a cloud application for a particular platform. They are supported by the platform operators with an open or proprietary language, a set of essential basic services to facilitate communication, monitoring, or service billing, and various other components, for instance to facilitate startup or ensure an application s scalability and/or elasticity.
PLATFORM AS A SERVICE (PAAS)
PLATFORM AS A SERVICE (PAAS) Application development framework. A robust application development framework built on technology that is widely used. Ideally, you should beware of the potential for vendor lock-in here. Open source platforms such as Java technology are usually a safe bet in this regard. Ease of use. A PaaS should come with easy-to-use WYSIWYG tools that have pre-built widgets, canned UI components, dragand-drop tools, and support for some standard IDEs. It should facilitate rapid, iterative application development. Business process modeling (BPM) tools. You need a strong BPM framework that allows you model your business process and build the application around it. Availability. The platform of choice should be accessible and available anywhere, anytime.
PLATFORM AS A SERVICE (PAAS) Scalability. The platform should be smart enough to leverage the elastic capacity of an underlying infrastructure to handle the loads the application will be put under. Security. To effectively combat threats, the platform should address things like cross-site scripting, SQL injection, Denial of Service, and encryption of traffic and make it ingrained into the application development. In addition, the platform must support single sign-on capabilities for you to be able to integrate it with your remaining on-premise applications or any other cloud applications. Inclusive. The platform should provide the ability to include, embed, and integrate other applications built on the same platform or others.
PLATFORM AS A SERVICE (PAAS) Portability. The platform should be agnostic to the underlying infrastructure and allow companies to move the application from another IaaS to another. Porting tools. To facilitate an easy and quick migration of data from the legacy on-premise application to the application based on the new platform, bulk import transformation tools are a necessary part of the platform's toolkit. API. To perform tasks such as user authentication and storing and retrieving files (for example, Web application files and assets) and sometimes even making calls directly to a database, the platform should have a well-documented API. This will allow your business to have the flexibility of creating and customizing a software application to interface with the platform that meets the specific needs of the company.
PLATFORM AS A SERVICE (PAAS)
INFRASTRUCTURE AS A SERVICE (IAAS) The services on the infrastructure layer are used to access essential IT resources that are combined under the heading Infrastructure-as-a-Service (IaaS). These essential IT resources include services linked to computing resources, data storage resources, and the communications channel. They enable existing applications to be provisioned on cloud resources and new services implemented on the higher layers.
INFRASTRUCTURE AS A SERVICE (IAAS) Physical resources are abstracted by virtualization, which means they can then be shared by several operating systems and end user environments on the virtual resources ideally, without any mutual interference. These virtualized resources usually comprise CPU and RAM, data storage resources (elastic block store and databases), and network resources.
INFRASTRUCTURE AS A SERVICE (IAAS)
INFRASTRUCTURE AS A SERVICE (IAAS) Large tracts of unused compute power and capacity that carry costs associated with the large amount of space consumed by the hardware in large, expensive data centers. Expensive manpower requirements, including 24-hour monitoring by network administrators located in the data centers where the infrastructure assets (servers, routers, switches, and so on) are held. A massive barrier to the Green Computing initiative as a result of the high level of wasteful energy consumption.
INFRASTRUCTURE AS A SERVICE (IAAS)
CROSS-CONCEPT MATRIX Paradigm shift Characteristics Key terms Advantages Disadvantages and risks When not to use IaaS Infrastructure as an asset Usually platform independent; infrastructure costs are shared and thus reduced; SLAs; pay by usage; self-scaling Grid computing, utility computing, compute instance, hypervisor, cloudbursting, multitenant computing, resource pooling Avoid capital expenditure on hardware and human resources; reduced ROI risk; low barriers to entry; streamlined and automated scaling Business efficiency and productivity largely depends on the vendor's capabilities; potentially greater long-term cost; centralization requires new/different security measures When capital budget is greater than operating budget PaaS License purchasing Consumes cloud infrastructure; caters to agile project management methods Solution stack Streamlined version deployment Centralization requires new/different security measures N/A SaaS Software as an asset (business and consumer) SLAs; UI powered by thin-client Thin client; client-server applications; cloud components; application communication via APIs; stateless; loosely coupled; modular; semantic interoperability Avoid capital expenditure on software and development resources; reduced ROI risk; streamlined and iterative updates Centralization of data requires new/different security measures N/A
BENEFITS Cost Savings Companies can reduce their capital expenditures and use operational expenditures for increasing their computing capabilities. This is a lower barrier to entry and also requires fewer in-house IT resources to provide system support. Scalability/Flexibility Companies can start with a small deployment and grow to a large deployment fairly rapidly, and then scale back if necessary. Also, the flexibility of cloud computing allows companies to use extra resources at peak times, enabling them to satisfy consumer demands.
BENEFITS Reliability Services using multiple redundant sites can support business continuity and disaster recovery. Maintenance Cloud service providers do the system maintenance, and access is through APIs that do not require application installations onto PCs, thus further reducing maintenance requirements. Mobile Accessible Mobile workers have increased productivity due to systems accessible in an infrastructure available from anywhere.
CHALLENGES Security and Privacy Perhaps two of the more hot button issues surrounding cloud computing relate to storing and securing data, and monitoring the use of the cloud by the service providers. These issues are generally attributed to slowing the deployment of cloud services. These challenges can be addressed, for example, by storing the information internal to the organization, but allowing it to be used in the cloud. For this to occur, though, the security mechanisms between organization and the cloud need to be robust and a Hybrid cloud could support such a deployment.
CHALLENGES Lack of Standards Clouds have documented interfaces; however, no standards are associated with these, and thus it is unlikely that most clouds will be interoperable. The Open Grid Forum is developing an Open Cloud Computing Interface to resolve this issue and the Open Cloud Consortium is working on cloud computing standards and practices. The findings of these groups will need to mature, but it is not known whether they will address the needs of the people deploying the services and the specific interfaces these services need. However, keeping up to date on the latest standards as they evolve will allow them to be leveraged, if applicable.
CHALLENGES Continuously Evolving User requirements are continuously evolving, as are the requirements for interfaces, networking, and storage. This means that a cloud, especially a public one, does not remain static and is also continuously evolving.
CHALLENGES Compliance Concerns The Sarbanes-Oxley Act (SOX) in the US and Data Protection directives in the EU are just two among many compliance issues affecting cloud computing, based on the type of data and application for which the cloud is being used. The EU has a legislative backing for data protection across all member states, but in the US data protection is different and can vary from state to state. As with security and privacy mentioned previously, these typically result in Hybrid cloud deployment with one cloud storing the data internal to the organization.
ENTERPRISE TO CLOUD
PRIVATE CLOUD
COMMUNITY CLOUD
HYBRID CLOUD
CASE STUDY : CLAN WARS Online multiplayer game In Browser Flash Processes credit card payments
CASE STUDY : CLAN WARS