IT Infrastructure and Cloud Computing Terms in this set (43) Client Server Computing A model where a server supports processing requests from remote clients, providing access to web pages, email, files, data, or software applications. 2-tier and 3-tie

IT Infrastructure and Cloud Computing Terms in this set (43) Client Server Computing A model where a server supports processing requests from remote clients, providing access to web pages, email, files, data, or software applications. 2-tier and 3-tier architecture The structure for computer processing, with 2-tier being used in distributed environments and 3-tier having presentation, application, and data tiers. Server Racks Equipment used to interface many servers, often done remotely using a special keyboard, video, and mouse (KVM). Data Centers Facilities housing thousands of servers, enabling cloud computing and providing storage and access to data. Cloud Computing Storing information at a place accessible through the internet using multiple devices, with resources rented from cloud service providers. Thin Client Client with little or no application programs executed locally. Thick Client Client with most application programs executed locally and some others executed on the server. Elastic leasing of pooled computer resources over the Internet Dynamically increasing or decreasing leased computing resources, paying only for what is used, and sharing physical hardware through virtualization. SaaS Software hosted on the provider's servers and licensed on a subscription basis, e.g., S, Office 365. (Software as a Service) CONSUME PaaS Allows users to create their own cloud applications using supplier-specific tools and services, e.g., Microsoft Azure, Oracle on Demand. (Platform as a Service) BUILD ON IT IaaS Basic cloud offering hosting bare servers and storage, allowing users to run any applications they prefer, e.g., Amazon EC2, Amazon S3. (Infrastructure as a Service) MIGRATE TO IT Public, Private and Hybrid Clouds Different types of cloud computing deployment models, with public being open to the public, private being for a single organization, and hybrid being a combination of both. Virtual Machine Monitor/Hypervisor Software allowing one physical machine to run multiple virtual machines, enabling the consolidation of servers and reducing operational costs in data centers. IT Infrastructure and Cloud Computing Exponential growth in computing Significant and rapid increase in the capacity and capabilities of computing. 2 tier architecture Presentation and application tier E-commerce three tier architecture Presentation, application, and data tier Presentation tier Presents the output to the users Application tier Runs application programs Data tier Provides storage and access to data The Cloud A network of servers and Elastic leasing of pooled computer resources over the internet Business benefits of the cloud Efficient, cost-effective, quickly access more resources or quickly downscale or reduce resources Business view of the cloud Cloud computing allows people ACCESS to the APPLICATIONS and the COMPUTING RESOURCES THROUGH THE INTERNET for which, in the past, people would use COMPUTERS or SERVERS in THEIR BUILDING Elastic Computing resources that are leased can be increased or decreased dynamically, programmatically, in a short span of time. Organizations pay for just the resources that they use Pool Resources Many different organizations use the same physical hardware. They share hardware through virtualization. Cloud vendors dynamically allocate more or less virtual machines as customer needs increase or decrease. WIN-WIN for both providers and client Two requirements for Cloud Computing Virtualization and Broad Internet Virtualization A technology that enables instantaneous creations or new virtual machines. One physical machine running multiple machines so multiple copies of OS software can run on a single server Broad Internet Makes high speed and low-cost data communication possible Benefits of virtualization Significantly reduce operational costs (power, equipment, space, networks, labors, etc) for datacenters Private Clouds You purchase the sole use of a server Private Clouds Pros Share overheads, 'ring fenced' servers Private Cloud Cons Inflexible so likely to pay for unused resource Public clouds You purchase capacity on a usage basis Public clouds pros shared overheads, purchase capacity on demand Public clouds cons no control of resources used or who shares them Hybrid clouds You can purchase the use of a mix of dedicated physical servers and virtual servers Hybrid clouds pros tailor mix to suit capacity and security requirements Hybrid clouds cons May still pay for unused resource When does the Cloud not make sense? When law or standard industry practice require physical control or possession of the data (private cloud may still work) Cloud (in general) pros -Small capital requirements -Speedy development, flexible and adaptable to growing or fluctuation demand - Known cost structure possible best-of-breed security/disaster preparedness -No obsolescence -Industry-wide economics of scale (hence cheaper) IT Infrastructure and Cloud Computing Cloud (in-general) cons -Dependency on vendor -Loss of control over data location -Little visibility into true security and disaster preparedness capabilities In-House cons -Significant capital required -Significant development effort -Annual maintenance costs -Ongoing support costs -Staff and train personnel -Increased management requirements -Difficult (impossible?) to accommodate fluctuating demand -Cost uncertainties -Obsolesce