Cloud Computing Tutorial
Through this Technology post we are going to guide you about “What is Cloud Computing” Cloud Computing is an IT paradigm that enables ubiquitous access to shared pools of configurable system resources and higher-level services that can be rapidly provisioned with minimal management effort, often over the Internet. It relies on sharing of resources to achieve coherence and economies of scale, similar to a public utility. Third-party clouds enable organizations to focus on their core businesses instead of expending resources on computer infrastructure and maintenance.
It is any physical or virtual component of limited availability within a computer system. Every device connected to a computer system is a resource. Every internal system component is a resource. Virtual system resources include files, network connections, and memory areas. Some resources, notably memory and storage space, have a notion of “location”, and one can distinguish contiguous allocations from non-contiguous allocations. For example, allocating 2 GB of memory in a single block, versus allocating it in 2,048 blocks each of size 2 MiB. The latter is known as fragmentation, and often severely impacts performance, so contiguous free space is a subcategory of the general resource of storage space.
It involves the process of preparing and equipping a network to allow it to provide new services to its users. In National Security/Emergency Preparedness telecommunications services, “provisioning” equates to “initiation” and includes altering the state of an existing priority service or capability. The concept of network provisioning or service mediation, mostly used in the telecommunication industry, refers to the provisioning of the customer’s services to the network elements.[clarification needed] It requires the existence of networking equipment and depends on network planning and design. In a modern signal infrastructure employing information technology (IT) at all levels, there is no possible distinction between telecommunications services and “higher level” infrastructure. Accordingly, provisioning configures any required systems, provides users with access to data and technology resources, and refers to all enterprise-level information-resource management involved.
It is one of provisioning type. The services which are assigned to the customer in the customer relationship management have to be provisioned on the network element which is enabling the service and allows the customer to actually use the service. The relation between a service configured in the CRM and a service on the network elements is not necessarily a 1:1 relation. Some services can be enabled by more than one network element, e.g. the Microsoft Media Server service. During the provisioning, the service mediation device translates the service and the corresponding parameters of the service to one or more services/parameters on the network elements involved. The algorithm used to translate a system service into network services is called provisioning logic. Electronic invoice feeds from your carriers can be automatically downloaded directly into the core of the telecom expense management (TEM) software and it will immediately conduct an audit of each single line item charge all the way down to the User Support and Operations Center level. The provisioning software will capture each circuit number provided by all of your carriers and if bills outside of the contracted rate an exception rule will trigger a red flag and notify the pre-established staff member to review the billing error.
It is a set of actions to prepare a server with appropriate systems, data and software, and make it ready for network operation. Typical tasks when provisioning a server are: select a server from a pool of available servers, load the appropriate software, appropriately customize and configure the system and the software to create or change a boot image for this server, and then change its parameters, such as IP address, IP Gateway to find associated network and storage resources (sometimes separated as resource provisioning) to audit the system. By auditing the system, you ensure OVAL compliance with limit vulnerability, ensure compliance, or install patches. After these actions, you restart the system and load the new software. This makes the system ready for operation. Typically an internet service provider (ISP) or Network Operations Center will perform these tasks to a well-defined set of parameters, for example, a boot image that the organization has approved and which uses software it has license to. Many instances of such a boot image create a virtual dedicated host.
It refers to the creation, maintenance and deactivation of user objects and user attributes, as they exist in one or more systems, directories or applications, in response to automated or interactive business processes. User provisioning software may include one or more of the following processes: change propagation, self-service workflow, consolidated user administration, delegated user administration, and federated change control. User objects may represent employees, contractors, vendors, partners, customers or other recipients of a service. Services may include electronic mail, inclusion in a published user directory, access to a database, access to a network or mainframe, etc. User provisioning is a type of identity management software, particularly useful within organizations, where users may be represented by multiple objects on multiple systems and multiple instances.
Mobile Subscriber Provisioning:
It refers to the setting up of new services, such as GPRS, MMS and Instant Messaging for an existing subscriber of a mobile phone network, and any gateways to standard Internet chat or mail services. The network operator typically sends these settings to the subscriber’s handset using SMS text services or HTML, and less commonly WAP, depending on what the mobile operating systems can accept. A general example of provisioning is with data services. A mobile user who is using his or her device for voice calling may wish to switch to data services in order to read emails or browse the Internet. The mobile device’s services are “provisioned” and thus the user is able to stay connected through push emails and other features of smartphone services.
Mobile Content Provisioning:
This refers to delivering mobile content, such as mobile internet to a mobile phone, agnostic of the features of said device. These may include operating system type and versions, Java version, browser version, screen form factors, audio capabilities, language settings and a plethora of other characteristics. As of April 2006, an estimated 5000 permutations are relevant. Mobile content provisioning facilitates a common user experience, though delivered on widely different handsets.
Internet Access Provisioning:
When getting a user / customer online, beyond user provisioning and network provisioning, the client system must be configured. This process may include many steps, depending on the connection technology in question (DSL, Cable, Fibre, etc.).
The possible steps are:
authentication with network
setup Wireless LAN
secure operating system (primarily for Windows only)
configure browser provider-specifics
e-mail provisioning (create mailboxes and aliases)
e-mail configuration in client systems
install additional support software
install add-on packages purchased by the customer
There are 4 approaches to provisioning an internet access:
Hand out manuals. Manuals are a great help for experienced users, but inexperienced users will need to call the support hotline several times until all internet services are accessible. Every unintended change in the configuration, by user mistake or due to a software error, results in additional calls. On-site setup by a technician. Sending a technician on-site is the most reliable approach from the provider’s point of view, as the person ensures that the internet access is working, before leaving the customer’s premises. This advantage comes at high costs – either for the provider or the customer, depending on the business model. Furthermore, it is inconvenient for customers, as they have to wait until they get an installation appointment and because they need to take a day off from work. For repairing an internet connection on-site or phone support will be needed again. Server-side remote setup. Server-side modem configuration uses a protocol called TR-069. It is widely established and reliable. At the current stage it can only be used for modem configuration. Protocol extensions are discussed, but not yet practically implemented, particularly because most client devices and applications do not support them yet. All other steps of the provisioning process are left to the user, typically causing lots of rather long calls to the support hotline. Installation CD. Also called a “client-side self-service installation” CD, it can cover the entire process from modem configuration to setting up client applications, including home networking devices. The software typically acts autonomously, i.e. it doesn’t need an online connection and an expensive backend infrastructure. During such an installation process the software usually also install diagnosis and self-repair applications that support customers in case of problems, avoiding costly hotline calls. Such client-side applications also open completely new possibilities for marketing, cross- and up-selling. Such solutions come from highly specialised companies or directly from the provider’s development department.
Since the launch of Amazon EC2 in 2006, the availability of high-capacity networks, low-cost computers and storage devices as well as the widespread adoption of hardware virtualization, service-oriented architecture, and autonomic and utility computing has led to growth in cloud computing. While the term “cloud computing” was popularized with Amazon.com releasing its Elastic Compute Cloud product in 2006, references to the phrase “cloud computing” appeared as early as 1996, with the first known mention in a Compaq internal document. The cloud symbol was used to represent networks of computing equipment in the original ARPANET by as early as 1977, and the CSNET by 1981 — both predecessors to the Internet itself. The word cloud was used as a metaphor for the Internet and a standardized cloud-like shape was used to denote a network on telephony schematics. With this simplification, the implication is that the specifics of how the end points of a network are connected are not relevant for the purposes of understanding the diagram.The term cloud was used to refer to platforms for distributed computing as early as 1993, when Apple spin-off General Magic and AT&T used it in describing their Telescript and PersonaLink technologies. During the 1960s, the initial concepts of time-sharing became popularized via RJE (Remote Job Entry); this terminology was mostly associated with large vendors such as IBM and DEC. Full-time-sharing solutions were available by the early 1970s on such platforms as Multics (on GE hardware), Cambridge CTSS, and the earliest UNIX ports (on DEC hardware). Yet, the “data center” model where users submitted jobs to operators to run on IBM mainframes was overwhelmingly predominant. In the 1990s, telecommunications companies, who previously offered primarily dedicated point-to-point data circuits, began offering virtual private network (VPN) services with comparable quality of service, but at a lower cost. By switching traffic as they saw fit to balance server use, they could use overall network bandwidth more effectively. They began to use the cloud symbol to denote the demarcation point between what the provider was responsible for and what users were responsible for. Cloud computing extended this boundary to cover all servers as well as the network infrastructure. As computers became more diffused, scientists and technologists explored ways to make large-scale computing power available to more users through time-sharing. They experimented with algorithms to optimize the infrastructure, platform, and applications to prioritize CPUs and increase efficiency for end users.
Cloud computing exhibits the following key characteristics:
Agility for organizations may be improved, as cloud computing may increase users’ flexibility with re-provisioning, adding, or expanding technological infrastructure resources.
Cost reductions are claimed by cloud providers. A public-cloud delivery model converts capital expenditures to operational expenditure. This purportedly lowers barriers to entry, as infrastructure is typically provided by a third party and need not be purchased for one-time or infrequent intensive computing tasks. Pricing on a utility computing basis is “fine-grained”, with usage-based billing options. As well, less in-house IT skills are required for implementation of projects that use cloud computing. The e-FISCAL project’s state-of-the-art repository contains several articles looking into cost aspects in more detail, most of them concluding that costs savings depend on the type of activities supported and the type of infrastructure available in-house.
Device and location independence enable users to access systems using a web browser regardless of their location or what device they use. As infrastructure is off-site and accessed via the Internet, users can connect to it from anywhere.
Maintenance of cloud computing applications is easier, because they do not need to be installed on each user’s computer and can be accessed from different places
Multitenancy enables sharing of resources and costs across a large pool of users thus allowing for:
centralization of infrastructure in locations with lower costs
peak-load capacity increases
utilisation and efficiency improvements for systems that are often only 10–20% utilised.
Performance is monitored by IT experts from the service provider, and consistent and loosely coupled architectures are constructed using web services as the system interface.
Resource pooling is the provider’s computing resources are commingle to serve multiple consumers using a multi-tenant model with different physical and virtual resources dynamically assigned and reassigned according to user demand. There is a sense of location independence in that the consumer generally have no control or knowledge over the exact location of the provided resource.
Productivity may be increased when multiple users can work on the same data simultaneously, rather than waiting for it to be saved and emailed. Time may be saved as information does not need to be re-entered when fields are matched, nor do users need to install application software upgrades to their computer.
Reliability improves with the use of multiple redundant sites, which makes well-designed cloud computing suitable for business continuity and disaster recovery.
Scalability and elasticity via dynamic (“on-demand”) provisioning of resources on a fine-grained, self-service basis in near real-time, without users having to engineer for peak loads.This gives the ability to scale up when the usage need increases or down if resources are not being used.
Security can improve due to centralization of data, increased security-focused resources, etc., but concerns can persist about loss of control over certain sensitive data, and the lack of security for stored kernels. Security is often as good as or better than other traditional systems, in part because service providers are able to devote resources to solving security issues that many customers cannot afford to tackle or which they lack the technical skills to address. However, the complexity of security is greatly increased when data is distributed over a wider area or over a greater number of devices, as well as in multi-tenant systems shared by unrelated users. In addition, user access to security audit logs may be difficult or impossible. Private cloud installations are in part motivated by users’ desire to retain control over the infrastructure and avoid losing control of information security.