Think of this list as the progression of the type of hosting a growing online business can consider.
The origin of the term cloud computing is obscure, but it appears to derive from the practice of using drawings of stylized clouds to denote networks in diagrams of computing and communications systems. The word cloud is used as a metaphor for the Internet, based on the standardized use of a cloud-like shape to denote a network on telephony schematics and later to depict the Internet in computer network diagrams as an abstraction of the underlying infrastructure it represents. The cloud symbol was used to represent the Internet as early as 1994.[5][6]
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 much lower cost. By switching traffic to balance utilization as they saw fit, they were able to utilize their overall network bandwidth more effectively. The cloud symbol was used to denote the demarcation point between that which was the responsibility of the provider and that which was the responsibility of the users. Cloud computing extends this boundary to cover servers as well as the network infrastructure.[7]
The underlying concept of cloud computing dates back to the 1950s; when large-scale mainframe became available in academia and corporations, accessible via thin clients / terminal computers. Because it was costly to buy a mainframe, it became important to find ways to get the greatest return on the investment in them, allowing multiple users to share both the physical access to the computer from multiple terminals as well as to share the CPU time, eliminating periods of inactivity, which became known in the industry as time-sharing.[8]
As computers became more prevalent, scientists and technologists explored ways to make large-scale computing power available to more users through time sharing, experimenting with algorithms to provide the optimal use of the infrastructure, platform and applications with prioritized access to the CPU and efficiency for the end users.[9]
John McCarthy opined in the 1960s that "computation may someday be organized as a public utility." Almost all the modern-day characteristics of cloud computing (elastic provision, provided as a utility, online, illusion of infinite supply), the comparison to the electricity industry and the use of public, private, government, and community forms, were thoroughly explored in Douglas Parkhill's 1966 book, The Challenge of the Computer Utility. Other scholars have shown that cloud computing's roots go all the way back to the 1950s when scientist Herb Grosch (the author of Grosch's law) postulated that the entire world would operate on dumb terminals powered by about 15 large data centers.[10] Due to the expense of these powerful computers, many corporations and other entities could avail themselves of computing capability through time sharing and several organizations, such as GE's GEISCO, IBM subsidiary The Service Bureau Corporation (SBC, founded in 1957), Tymshare (founded in 1966), National CSS (founded in 1967 and bought by Dun & Bradstreet in 1979), Dial Data (bought by Tymshare in 1968), and Bolt, Beranek and Newman (BBN) marketed time sharing as a commercial venture.
The development of the Internet from being document centric via semantic data towards more and more services was described as "Dynamic Web".[11] This contribution focused in particular in the need for better meta-data able to describe not only implementation details but also conceptual details of model-based applications.
The ubiquitous availability of high-capacity networks, low-cost computers and storage devices as well as the widespread adoption of hardware virtualization, service-oriented architecture, autonomic, and utility computing have led to a tremendous growth in cloud computing.[12][13][14]
After the dot-com bubble, Amazon played a key role in the development of cloud computing by modernizing their data centers, which, like most computer networks, were using as little as 10% of their capacity at any one time, just to leave room for occasional spikes. Having found that the new cloud architecture resulted in significant internal efficiency improvements whereby small, fast-moving "two-pizza teams" (teams small enough to be fed with two pizzas) could add new features faster and more easily, Amazon initiated a new product development effort to provide cloud computing to external customers, and launched Amazon Web Service (AWS) on a utility computing basis in 2006.[15][16]
In late 2007 Ben Dorsi-Todaro demonstrated in his Tech Me Out blog post titled We Are Obsolete a crude yet affordable method for an average computer user to achieve a the basic concept of cloud computing from the comfort of a person's own home.
In early 2008, Eucalyptus became the first open-source, AWS API-compatible platform for deploying private clouds. In early 2008, OpenNebula, enhanced in the RESERVOIR European Commission-funded project, became the first open-source software for deploying private and hybrid clouds, and for the federation of clouds.[17] In the same year, efforts were focused on providing quality of service guarantees (as required by real-time interactive applications) to cloud-based infrastructures, in the framework of the IRMOS European Commission-funded project, resulting to a real-time cloud environment.[18] By mid-2008, Gartner saw an opportunity for cloud computing "to shape the relationship among consumers of IT services, those who use IT services and those who sell them"[19] and observed that "organisations are switching from company-owned hardware and software assets to per-use service-based models" so that the "projected shift to computing... will result in dramatic growth in IT products in some areas and significant reductions in other areas."[20]
On March 1, 2011, IBM announced the Smarter Computing framework to support Smarter Planet.[21] Among the various components of the Smarter Computing foundation, cloud computing is a critical piece.
In 2012, Dr. Biju John and Dr. Souheil Khaddaj describe the cloud as a virtualized, semantic source of information: "Cloud computing is a universal collection of data which extends over the internet in the form of resources (such as information hardware, various platforms, services etc.) and forms individual units within the virtualization environment. Held together by infrastructure providers, service providers and the consumer, then it is semantically accessed by various users."[citation needed]
Cloud computing types
Cloud computing sample architecture
Cloud architecture,[56] the systems architecture of the software systems involved in the delivery of cloud computing, typically involves multiple cloud components communicating with each other over a loose coupling mechanism such as a messaging queue. Elastic provision implies intelligence in the use of tight or loose coupling as applied to mechanisms such as these and others.
As can be expected with any revolutionary change in the landscape of global computing, certain legal issues arise; everything from trademark infringement, security concerns to the sharing of propriety data resources.
1. Shared Hosting
Shared hosting means just that. Your website is hosted on a server shared by other websites. The advantage of this setup is the shared cost. You can pay as little as $5-$10 per month for sharing a super server with (probably) hundreds of other websites. The biggest disadvantage of a shared hosting account is that you're at the mercy of the other sites on your server. A really popular site may adversely affect the performance of your own site. On the other hand, if you're the most popular site on the server, you get to use a super server for a very low price.2. Reseller Hosting
Reseller hosting packages is basically a shared hosting account with extra tools to help you resell hosting space. Reseller packages come with greater technical control (often via the Web Host Manager (WHM) control panel), billing software to help you invoice clients, and other extra perks. Some of those perks include:- free website templates
- white label technical support -- that means the hosting company handles your clients' tech support issues
- private name servers -- make your company seem even bigger by telling your clients to point their domain nameservers to ns1.yourwebdesignfirm.com
3. Grid / Cloud Hosting
Grid or Cloud Hosting refers to a fairly new hosting technology that lets hundreds of individual servers work together so that it looks like one giant server. The idea is that as the need grows, the hosting company can just add more commodity hardware to make an ever larger grid or cloud. Price Range: All grid computing packages use some form of pay-for-what-you-use pricing structure. Base prices start at $20 for Media Temple and $100 for Mosso (a Rackspace company). Both charge more for extra bandwidth, CPU processing, memory usage, or other resource usage. Amazon's Elastic Compute Cloud (EC2) has no minimum monthly fee (you pay for only what you use), but requires more tech savvy to get started (price calculator).4. Virtual Private Server (VPS)
Virtual private servers share one physical server but acts like multiple, separate servers. A VPS is a stepping stone between shared hosting and getting your own dedicated machine. Even though each VPS instance shares hardware resources, they are allocated a dedicated slice of the computing resources. A VPS avoids the problem of having your hosting neighbors bring down your website, while avoiding the cost of a dedicated server. Price Range: Most VPS hosting packages cost between $50 and $200. Pricing is based on the guaranteed CPU and memory (RAM) you get. Here is a list of reliable VPS hosting providers.5. Dedicated Server
When you have a dedicated server, it means you are renting one physical server from a hosting company. You can have full control (called "root" permissions in Linux) if you want it. Pricing: Dedicated servers are priced from $100 and up. But if you are considering a dedicated server, you should also consider the costs of hiring a sysadmin to take care of the box.6. Colocation
When you colocate, you rent rack space from a data center. You bring in your own server hardware and they provide power, cooling, physical security, and an internet uplink. This means you're responsible for your own server software, data storage, backup procedures, etc. If hardware fails, you're responsible for replacing it and getting the server back up and running. Unless you have the technical know-how in-house, colocation is probably not worth the investment in time, expertise, and money for most small businesses.7. Self Service
The ultimate hosting plan -- you do it all yourself! You buy the servers, install and configure the software, make sure there is sufficient cooling and power in your machine room, and double up everything for redundancy. Some of the things you'll have to take care of:- data center space
- cooling
- power (with backup)
- bandwidth
- server hardware
- systems administrator
- data integrity and backup
- ... and the list goes on.
- Free web hosting service: offered by different companies with limited services, sometimes supported by advertisements, and often limited when compared to paid hosting.
- Shared web hosting service: one's website is placed on the same server as many other sites, ranging from a few to hundreds or thousands. Typically, all domains may share a common pool of server resources, such as RAM and the CPU. The features available with this type of service can be quite extensive. A shared web may be hosted with a reseller.
- Reseller web hosting: allows clients to become web hosts themselves. Resellers could function, for individual domains, under any combination of these listed types of hosting, depending on who they are affiliated with as a reseller. Resellers' accounts may vary tremendously in size: they may have their own virtual dedicated server to a colocated server. Many resellers provide a nearly identical service to their provider's shared hosting plan and provide the technical support themselves.
- Virtual Dedicated Server: also known as a Virtual Private Server (VPS), divides server resources into virtual servers, where resources can be allocated in a way that does not directly reflect the underlying hardware. VPS will often be allocated resources based on a one server to many VPSs relationship, however virtualisation may be done for a number of reasons, including the ability to move a VPS container between servers. The users may have root access to their own virtual space. Customers are sometimes responsible for patching and maintaining the server.
- Dedicated hosting service: the user gets his or her own Web server and gains full control over it (user has root access for Linux/administrator access for Windows); however, the user typically does not own the server. Another type of Dedicated hosting is Self-Managed or Unmanaged. This is usually the least expensive for Dedicated plans. The user has full administrative access to the server, which means the client is responsible for the security and maintenance of his own dedicated server.
- Managed hosting service: the user gets his or her own Web server but is not allowed full control over it (user is denied root access for Linux/administrator access for Windows); however, they are allowed to manage their data via FTP or other remote management tools. The user is disallowed full control so that the provider can guarantee quality of service by not allowing the user to modify the server or potentially create configuration problems. The user typically does not own the server. The server is leased to the client.
- Colocation web hosting service: similar to the dedicated web hosting service, but the user owns the colo server; the hosting company provides physical space that the server takes up and takes care of the server. This is the most powerful and expensive type of web hosting service. In most cases, the colocation provider may provide little to no support directly for their client's machine, providing only the electrical, Internet access, and storage facilities for the server. In most cases for colo, the client would have his own administrator visit the data center on site to do any hardware upgrades or changes.
- Cloud hosting: is a new type of hosting platform that allows customers powerful, scalable and reliable hosting based on clustered load-balanced servers and utility billing. A cloud hosted website may be more reliable than alternatives since other computers in the cloud can compensate when a single piece of hardware goes down. Also, local power disruptions or even natural disasters are less problematic for cloud hosted sites, as cloud hosting is decentralized. Cloud hosting also allows providers to charge users only for resources consumed by the user, rather than a flat fee for the amount the user expects they will use, or a fixed cost upfront hardware investment. Alternatively, the lack of centralization may give users less control on where their data is located which could be a problem for users with data security or privacy concerns.
- Clustered hosting: having multiple servers hosting the same content for better resource utilization. Clustered Servers are a perfect solution for high-availability dedicated hosting, or creating a scalable web hosting solution. A cluster may separate web serving from database hosting capability. (Usually Web hosts use Clustered Hosting for their Shared hosting plans, as there are multiple benefits to the mass managing of clients)
- Grid hosting: this form of distributed hosting is when a server cluster acts like a grid and is composed of multiple nodes.
- Home server: usually a single machine placed in a private residence can be used to host one or more web sites from a usually consumer-grade broadband connection. These can be purpose-built machines or more commonly old PCs. Some ISPs actively attempt to block home servers by disallowing incoming requests to TCP port 80 of the user's connection and by refusing to provide static IP addresses. A common way to attain a reliable DNS host name is by creating an account with a dynamic DNS service. A dynamic DNS service will automatically change the IP address that a URL points to when the IP address changes.
- File hosting service: hosts files, not web pages
- Image hosting service
- Video hosting service
- Blog hosting service
- Paste bin
- Shopping cart software
- E-mail hosting service
Obtaining hosting
Web hosting is often provided as part of a general Internet access plan; there are many free and paid providers offering these types of web hosting. A customer needs to evaluate the requirements of the application to choose what kind of hosting to use. Such considerations include database server software, scripting software, and operating system. Most hosting providers provide Linux-based web hosting which offers a wide range of different software. A typical configuration for a Linux server is the LAMP platform: Linux, Apache, MySQL, and PHP/Perl/Python. The web hosting client may want to have other services, such as email for their business domain, databases or multi-media services for streaming media. A customer may also choose Windows as the hosting platform. The customer still can choose from PHP, Perl, and Python but may also use ASP .Net or Classic ASP. Web hosting packages often include a Web Content Management System, so the end-user does not have to worry about the more technical aspects.Green hosting
From Wikipedia, the free encyclopedia
Green hosting or eco-friendly hosting is Internet hosting which involve green technologies to reduce environmental impact.
Green hosting include Carbon offsetting, powering a data center directly with renewable energy, planting trees, plants and grass around and over Data Centers and more day to day activities such as energy conservation and the use of energy saving appliances. Green hosting utilized green marketing with focusing on green consumers that are concerning about the environment.
World Internet usage statistics show that the Internet is still rapidly growing in the U.S. [1] and growing from 400 to 1000% a year, worldwide. In fact, the total electric bill to operate those servers and related infrastructure equipment was $2.7 billion in the United States and $7.2 billion worldwide.[2] It is estimated that if energy consumption with web hosting keeps raising at the current rate by 2020 the industry will be more polluting than the airline industry.[3] With so much demand on resources, eco-friendly hosting services emerged.
Cloud computing is the use of computing resources (hardware and software) that are delivered as a service over a network (typically the Internet). The name comes from the use of a cloud-shaped symbol as an abstraction for the complex infrastructure it contains in system diagrams. Cloud computing entrusts remote services with a user's data, software and computation.
There are many types of public cloud computing:[1]
- Infrastructure as a service (IaaS)
- Platform as a service (PaaS)
- Software as a service (SaaS)
- Storage as a service (STaaS)
- Security as a service (SECaaS)
- Data as a service (DaaS)
- Test environment as a service (TEaaS)
- Desktop as a service (DaaS)
- API as a service (APIaaS)
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History
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Similar systems and concepts
Cloud computing shares characteristics with:- Autonomic computing — Computer systems capable of self-management.[22]
- Client–server model — Client–server computing refers broadly to any distributed application that distinguishes between service providers (servers) and service requesters (clients).[23]
- Grid computing — "A form of distributed and parallel 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."
- Mainframe computer — Powerful computers used mainly by large organizations for critical applications, typically bulk data processing such as census, industry and consumer statistics, police and secret intelligence services, enterprise resource planning, and financial transaction processing.[24]
- Utility computing — The "packaging of computing resources, such as computation and storage, as a metered service similar to a traditional public utility, such as electricity."[25][26]
- Peer-to-peer — Distributed architecture without the need for central coordination, with participants being at the same time both suppliers and consumers of resources (in contrast to the traditional client–server model).
- Cloud gaming - Also called On-demand gaming is a way of delivering to games to computers. The gaming data will be stored in the provider's server, so that gaming will be independent of client computers used to play the game.
Characteristics
Cloud computing exhibits the following key characteristics:- Agility improves with users' ability to re-provision technological infrastructure resources.
- Application programming interface (API) accessibility to software that enables machines to interact with cloud software in the same way the user interface facilitates interaction between humans and computers. Cloud computing systems typically use REST-based APIs.
- Cost is claimed to be reduced and in a public cloud delivery model capital expenditure is converted to operational expenditure.[27] This is purported to lower barriers to entry, as infrastructure is typically provided by a third-party and does not need to be purchased for one-time or infrequent intensive computing tasks. Pricing on a utility computing basis is fine-grained with usage-based options and fewer IT skills are required for implementation (in-house).[28] The e-FISCAL project's state of the art repository[29] 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[30] enable users to access systems using a web browser regardless of their location or what device they are using (e.g., PC, mobile phone). As infrastructure is off-site (typically provided by a third-party) and accessed via the Internet, users can connect from anywhere.[28]
- Virtualization technology allows servers and storage devices to be shared and utilization be increased. Applications can be easily migrated from one physical server to another.
- Multitenancyenables sharing of resources and costs across a large pool of users thus allowing for:
- Centralization of infrastructure in locations with lower costs (such as real estate, electricity, etc.)
- Peak-load capacity increases (users need not engineer for highest possible load-levels)
- Utilisation and efficiency improvements for systems that are often only 10–20% utilised.[15]
- Reliability is improved if multiple redundant sites are used, which makes well-designed cloud computing suitable for business continuity and disaster recovery.[31]
- Scalability and elasticity via dynamic ("on-demand") provisioning of resources on a fine-grained, self-service basis near real-time, without users having to engineer for peak loads.[32][33]
- Performance is monitored, and consistent and loosely coupled architectures are constructed using web services as the system interface.[28]
- Security could 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.[34] Security is often as good as or better than other traditional systems, in part because providers are able to devote resources to solving security issues that many customers cannot afford.[35] However, the complexity of security is greatly increased when data is distributed over a wider area or greater number of devices and in multi-tenant systems that are being 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.
- 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.
On-demand self-service
See also: Self-service provisioning for cloud computing services and Service catalogs for cloud computing services
On-demand self-service allows users to obtain, configure and deploy cloud services themselves using cloud service catalogues, without requiring the assistance of IT.[36][37] This feature is listed by the The National Institute of Standards and Technology (NIST) as a characteristic of cloud computing.[38]
The self-service requirement of cloud computing prompts infrastructure vendors to create cloud computing templates, which are obtained from cloud service catalogues. Manufacturers of such templates or blueprints include Hewlett-Packard (HP), which names its templates as HP Cloud Maps[39] RightScale[40] and Red Hat, which names its templates CloudForms.[41]
The templates contain predefined configurations used to by consumers to set up cloud services. The templates or blueprints provide the technical information necessary to build ready-to-use clouds.[40] Each template includes specific configuration details for different cloud infrastructures, with information about servers for specific tasks such as hosting applications, databases, websites and so on.[40] The templates also include predefined Web service, the operating system, the database, security configurations and load balancing.[41]
Cloud consumers use cloud templates to move applications between clouds through a self-service portal. The predefined blueprints define all that an application requires to run in different environments. For example, a template could define how the same application could be deployed in cloud platforms based on Amazon Web Service, VMware or Red Hat.[42] The user organisation benefits from cloud templates because the technical aspects of cloud configurations reside in the templates, letting users to deploy cloud services with a push of a button.[43][44] Cloud templates can also be used by developers to create a catalog of cloud services.[45]
Service models
Cloud computing providers offer their services according to three fundamental models:[4][46] Infrastructure as a service (IaaS), platform as a service (PaaS), and software as a service (SaaS) where IaaS is the most basic and each higher model abstracts from the details of the lower models.Infrastructure as a service (IaaS)
See also: Category:Cloud infrastructure
In this most basic cloud service model, cloud providers offer computers, as physical or more often as virtual machines, and other resources. The virtual machines are run as guests by a hypervisor, such as Xen or KVM. Management of pools of hypervisors by the cloud operational support system leads to the ability to scale to support a large number of virtual machines. Other resources in IaaS clouds include images in a virtual machine image library, raw (block) and file-based storage, firewalls, load balancers, IP addresses, virtual local area networks (VLANs), and software bundles.[47] Amies, Alex; Sluiman, Harm; Tong IaaS cloud providers supply these resources on demand from their large pools installed in data centers. For wide area connectivity, the Internet can be used or—in carrier clouds -- dedicated virtual private networks can be configured., Qiang Guo (July 2012). "Infrastructure as a Service Cloud Concepts". Developing and Hosting Applications on the Cloud. IBM Press. ISBN 978-0-13-306684-5.
To deploy their applications, cloud users then install operating system images on the machines as well as their application software. In this model, it is the cloud user who is responsible for patching and maintaining the operating systems and application software. Cloud providers typically bill IaaS services on a utility computing basis, that is, cost will reflect the amount of resources allocated and consumed.
IaaS refers not to a machine that does all the work, but simply to a facility given to businesses that offers users the leverage of extra storage space in servers and data centers.
Examples of IaaS include: Amazon CloudFormation (and underlying services such as Amazon EC2), Rackspace Cloud, Terremark and Google Compute Engine.
Platform as a service (PaaS)
Main article: Platform as a service
See also: Category:Cloud platforms
In the PaaS model, cloud providers deliver a computing platform typically including operating system, programming language execution environment, database, and web server. Application developers can develop and run their software solutions on a cloud platform without the cost and complexity of buying and managing the underlying hardware and software layers. With some PaaS offers, the underlying computer and storage resources scale automatically to match application demand such that cloud user does not have to allocate resources manually.
Examples of PaaS include: Amazon Elastic Beanstalk, Cloud Foundry, Heroku, Force.com, EngineYard, Mendix, Google App Engine, Microsoft Azure and OrangeScape.
Software as a service (SaaS)
Main article: Software as a service
In this model, cloud providers install and operate application software in the cloud and cloud users access the software from cloud clients. The cloud users do not manage the cloud infrastructure and platform on which the application is running. This eliminates the need to install and run the application on the cloud user's own computers simplifying maintenance and support. What makes a cloud application different from other applications is its elasticity. This can be achieved by cloning tasks onto multiple virtual machines at run-time to meet the changing work demand.[48] Load balancers distribute the work over the set of virtual machines. This process is inconspicuous to the cloud user who sees only a single access point. To accommodate a large number of cloud users, cloud applications can be multitenant, that is, any machine serves more than one cloud user organization. It is common to refer to special types of cloud based application software with a similar naming convention: desktop as a service, business process as a service, test environment as a service, communication as a service.
The pricing model for SaaS applications is typically a monthly or yearly flat fee per user,[49] so price is scalable and adjustable if users are added or removed at any point.[50]
Examples of SaaS include: Google Apps, innkeypos, Quickbooks Online, Limelight Video Platform, Salesforce.com and Microsoft Office 365.
Cloud clients
See also: Category:Cloud clients
Users access cloud computing using networked client devices, such as desktop computers, laptops, tablets and smartphones. Some of these devices - cloud clients - rely on cloud computing for all or a majority of their applications so as to be essentially useless without it. Examples are thin clients and the browser-based Chromebook. Many cloud applications do not require specific software on the client and instead use a web browser to interact with the cloud application. With Ajax and HTML5 these Web user interfaces can achieve a similar or even better look and feel as native applications. Some cloud applications, however, support specific client software dedicated to these applications (e.g., virtual desktop clients and most email clients). Some legacy applications (line of business applications that until now have been prevalent in thin client Windows computing) are delivered via a screen-sharing technology.
Deployment models
Public cloud
Public cloud applications, storage, and other resources are made available to the general public by a service provider. These services are free or offered on a pay-per-use model. Generally, public cloud service providers like Amazon AWS, Microsoft and Google own and operate the infrastructure and offer access only via Internet (direct connectivity is not offered).[28]Community cloud
Community cloud shares infrastructure between several organizations from a specific community with common concerns (security, compliance, jurisdiction, etc.), whether managed internally or by a third-party and hosted internally or externally. The costs are spread over fewer users than a public cloud (but more than a private cloud), so only some of the cost savings potential of cloud computing are realized.[4]Hybrid cloud
Hybrid cloud is a composition of two or more clouds (private, community or public) that remain unique entities but are bound together, offering the benefits of multiple deployment models.[4] By utilizing "hybrid cloud" architecture, companies and individuals are able to obtain degrees of fault tolerance combined with locally immediate usability without dependency on internet connectivity. Hybrid cloud architecture requires both on-premises resources and off-site (remote) server-based cloud infrastructure. Hybrid clouds lack the flexibility, security and certainty of in-house applications.[51] Hybrid cloud provides the flexibility of in house applications with the fault tolerance and scalability of cloud based services.Private cloud
Private cloud is cloud infrastructure operated solely for a single organization, whether managed internally or by a third-party and hosted internally or externally.[4] Undertaking a private cloud project requires a significant level and degree of engagement to virtualize the business environment, and it will require the organization to reevaluate decisions about existing resources. When it is done right, it can have a positive impact on a business, but every one of the steps in the project raises security issues that must be addressed in order to avoid serious vulnerabilities.[52] They have attracted criticism because users "still have to buy, build, and manage them" and thus do not benefit from less hands-on management,[53] essentially "[lacking] the economic model that makes cloud computing such an intriguing concept".[54][55]Architecture
The Intercloud
Main article: Intercloud
The Intercloud[57] is an interconnected global "cloud of clouds"[58][59] and an extension of the Internet "network of networks" on which it is based.[60][61][62]
Cloud engineering
Cloud engineering is the application of engineering disciplines to cloud computing. It brings a systematic approach to the high-level concerns of commercialisation, standardisation, and governance in conceiving, developing, operating and maintaining cloud computing systems. It is a multidisciplinary method encompassing contributions from diverse areas such as systems, software, web, performance, information, security, platform, risk, and quality engineering.Issues
Privacy
The cloud model has been criticised by privacy advocates for the greater ease in which the companies hosting the cloud services control, thus, can monitor at will, lawfully or unlawfully, the communication and data stored between the user and the host company. Instances such as the secret NSA program, working with AT&T, and Verizon, which recorded over 10 million phone calls between American citizens, causes uncertainty among privacy advocates, and the greater powers it gives to telecommunication companies to monitor user activity.[63] Using a cloud service provider (CSP) can complicate privacy of data because of the extent to which virtualization for cloud processing (virtual machines) and cloud storage are used to implement cloud service.[64] The point is that CSP operations, customer or tenant data may not remain on the same system, or in the same data center or even within the same provider's cloud. This can lead to legal concerns over jurisdiction. While there have been efforts (such as US-EU Safe Harbor) to "harmonise" the legal environment, providers such as Amazon still cater to major markets (typically the United States and the European Union) by deploying local infrastructure and allowing customers to select "availability zones."[65] Cloud computing poses privacy concerns because the service provider may access the data that is on the cloud at any point in time. They could accidentally or deliberately alter or even delete information.[66] Postage and delivery services company, Pitney Bowes launched Volly, a cloud-based, digital mailbox service to leverage its communication management assets. They also faced the technical challenge of providing strong data security and privacy. However, they were able to address the same concern by applying customized, application-level security, including encryption. [67]Compliance
In order to obtain compliance with regulations including FISMA, HIPAA, and SOX in the United States, the Data Protection Directive in the EU and the credit card industry's PCI DSS, users may have to adopt community or hybrid deployment modes that are typically more expensive and may offer restricted benefits. This is how Google is able to "manage and meet additional government policy requirements beyond FISMA"[68][69] and Rackspace Cloud or QubeSpace are able to claim PCI compliance.[70] Many providers also obtain a SAS 70 Type II audit, but this has been criticised on the grounds that the hand-picked set of goals and standards determined by the auditor and the auditee are often not disclosed and can vary widely.[71] Providers typically make this information available on request, under non-disclosure agreement.[72][73] Customers in the EU contracting with cloud providers outside the EU/EEA have to adhere to the EU regulations on export of personal data.[74] U.S. Federal Agencies have been directed by the Office of Management and Budget to use a process called FedRAMP (Federal Risk and Authorization Management Program) to assess and authorize cloud products and services. Federal CIO Steven VanRoekel issued a memorandum to federal agency Chief Information Officers on December 8, 2011 defining how federal agencies should use FedRAMP. FedRAMP consists of a subset of NIST Special Publication 800-53 security controls specifically selected to provide protection in cloud environments. A subset has been defined for the FIPS 199 low categorization and the FIPS 199 moderate categorization. The FedRAMP program has also established a Joint Accreditation Board (JAB) consisting of Chief Information Officers from DoD, DHS and GSA. The JAB is responsible for establishing accreditation standards for 3rd party organizations who will perform the assessments of cloud solutions. The JAB will also review authorization packages and may grant provisional authorization (to operate). The federal agency consuming the service will still have the final responsibility for final authority to operate.[75]Legal
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This section requires expansion with: examples and additional citations. (August 2012) |
Open source
See also: Category:Free software for cloud computing
Open-source software has provided the foundation for many cloud computing implementations, prominent examples being the Hadoop framework[76] and VMware's Cloud Foundry.[77] In November 2007, the Free Software Foundation released the Affero General Public License, a version of GPLv3 intended to close a perceived legal loophole associated with free software designed to be run over a network.[78]
Open standards
See also: Category:Cloud standards
Most cloud providers expose APIs that are typically well-documented (often under a Creative Commons license[79]) but also unique to their implementation and thus not interoperable. Some vendors have adopted others' APIs and there are a number of open standards under development, with a view to delivering interoperability and portability.[80]
Security
Main article: Cloud computing security
As cloud computing is achieving increased popularity, concerns are being voiced about the security issues introduced through adoption of this new model. The effectiveness and efficiency of traditional protection mechanisms are being reconsidered as the characteristics of this innovative deployment model can differ widely from those of traditional architectures.[81] An alternative perspective on the topic of cloud security is that this is but another, although quite broad, case of "applied security" and that similar security principles that apply in shared multi-user mainframe security models apply with cloud security.[82]
The relative security of cloud computing services is a contentious issue that may be delaying its adoption.[83] Physical control of the Private Cloud equipment is more secure than having the equipment off site and under someone else’s control. Physical control and the ability to visually inspect the data links and access ports is required in order to ensure data links are not compromised. Issues barring the adoption of cloud computing are due in large part to the private and public sectors' unease surrounding the external management of security-based services. It is the very nature of cloud computing-based services, private or public, that promote external management of provided services. This delivers great incentive to cloud computing service providers to prioritize building and maintaining strong management of secure services.[84] Security issues have been categorised into sensitive data access, data segregation, privacy, bug exploitation, recovery, accountability, malicious insiders, management console security, account control, and multi-tenancy issues. Solutions to various cloud security issues vary, from cryptography, particularly public key infrastructure (PKI), to use of multiple cloud providers, standardisation of APIs, and improving virtual machine support and legal support.[81][85][86]
Cloud computing offers many benefits, but it also is vulnerable to threats. As the uses of cloud computing increase, it is highly likely that more criminals will try to find new ways to exploit vulnerabilities in the system. There are many underlying challenges and risks in cloud computing that increase the threat of data being compromised. To help mitigate the threat, cloud computing stakeholders should invest heavily in risk assessment to ensure that the system encrypts to protect data; establishes trusted foundation to secure the platform and infrastructure; and builds higher assurance into auditing to strengthen compliance. Security concerns must be addressed in order to establish trust in cloud computing technology.
Sustainability
Although cloud computing is often assumed to be a form of "green computing", there is no published study to substantiate this assumption.[87] citing the servers affects the environmental effects of cloud computing. In areas where climate favors natural cooling and renewable electricity is readily available, the environmental effects will be more moderate. (The same holds true for "traditional" data centers.) Thus countries with favorable conditions, such as Finland,[88] Sweden and Switzerland,[89] are trying to attract cloud computing data centers. Energy efficiency in cloud computing can result from energy-aware scheduling and server consolidation.[90] However, in the case of distributed clouds over data centers with different source of energies including renewable source of energies, a small compromise on energy consumption reduction could result in high carbon footprint reduction.[91]Abuse
As with privately purchased hardware, customers can purchase the services of cloud computing for nefarious purposes. This includes password cracking and launching attacks using the purchased services.[92] In 2009, a banking trojan illegally used the popular Amazon service as a command and control channel that issued software updates and malicious instructions to PCs that were infected by the malware.[93]IT governance
Main article: Corporate governance of information technology
The introduction of cloud computing requires an appropriate IT governance model to ensure a secured computing environment and to comply with all relevant organizational information technology policies.[94][95] As such, organizations need a set of capabilities that are essential when effectively implementing and managing cloud services, including demand management, relationship management, data security management, application lifecycle management, risk and compliance management.[96]
Research
Many universities, vendors and government organisations are investing in research around the topic of cloud computing:[97][98]- In October 2007, the Academic Cloud Computing Initiative (ACCI) was announced as a multi-university project designed to enhance students' technical knowledge to address the challenges of cloud computing.[99]
- In April 2009, UC Santa Barbara released the first open source platform-as-a-service, AppScale, which is capable of running Google App Engine applications at scale on a multitude of infrastructures.
- In April 2009, the St Andrews Cloud Computing Co-laboratory was launched, focusing on research in the important new area of cloud computing. Unique in the UK, StACC aims to become an international centre of excellence for research and teaching in cloud computing and will provide advice and information to businesses interested in using cloud-based services.[100]
- In October 2010, the TClouds (Trustworthy Clouds) project was started, funded by the European Commission's 7th Framework Programme. The project's goal is to research and inspect the legal foundation and architectural design to build a resilient and trustworthy cloud-of-cloud infrastructure on top of that. The project also develops a prototype to demonstrate its results.[101]
- In December 2010, the TrustCloud research project [102][103] was started by HP Labs Singapore to address transparency and accountability of cloud computing via detective, data-centric approaches[104] encapsulated in a five-layer TrustCloud Framework. The team identified the need for monitoring data life cycles and transfers in the cloud,[102] leading to the tackling of key cloud computing security issues such as cloud data leakages, cloud accountability and cross-national data transfers in transnational clouds.
- In July 2011, the High Performance Computing Cloud (HPCCLoud) project was kicked-off aiming at finding out the possibilities of enhancing performance on cloud environments while running the scientific applications - development of HPCCLoud Performance Analysis Toolkit which was funded by CIM-Returning Experts Programme - under the coordination of Prof. Dr. Shajulin Benedict.
- In June 2011, the Telecommunications Industry Association developed a Cloud Computing White Paper, to analyze the integration challenges and opportunities between cloud services and traditional U.S. telecommunications standards.[105]
- In 2011, FEMhub launched NCLab, a free SaaS application for science, technology, engineering and mathematics (STEM). NCLab has more than 10,000 users as of July 2012.
See also
- Cloud database
- Cloud computing comparison
- Cloud storage
- Web operating system
- Cloud collaboration
Contents
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Operating system support
Availability, price and employee familiarity often determines which operating systems are offered on dedicated servers. Variations of Linux and Unix (open source operating systems) are often included at no charge to the customer. Commercial operating systems include Microsoft Windows Server, provided through a special program called Microsoft SPLA. Red Hat Enterprise is a commercial version of Linux offered to hosting providers on a monthly fee basis. The monthly fee provides OS updates through the Red Hat Network using an application called yum. Other operating systems are available from the open source community at no charge. These include CentOS, Fedora Core, Debian, and many other Linux distributions or BSD systems FreeBSD, NetBSD, OpenBSD. Support for any of these operating systems typically depends on the level of management offered with a particular dedicated server plan. Operating system support may include updates to the core system in order to acquire the latest security fixes, patches, and system-wide vulnerability resolutions. Updates to core operating systems include kernel upgrades, service packs, application updates, and security patches that keep server secure and safe. Operating system updates and support relieves the burden of server management from the dedicated server owner.Bandwidth and connectivity
Bandwidth refers to the data transfer rate or the amount of data that can be carried from one point to another in a given time period (usually a second) and is often represented in bits (of data) per second (bit/s). For example, visitors to your server, web site, or applications utilize bandwidth *Third – Total Transfer (measured in bytes transferred) 95th percentile method: line speed, billed on the 95th percentile, refers to the speed in which data flows from the server or device, measured every 5 minutes for the month, and dropping the top 5% of measurements that are highest, and basing the usage for the month on the next-highest measurement. This is similar to a median measurement, which can be thought of as a 50th percentile measurement (with 50% of measurements above, and 50% of measurements below), whereas this sets the cutoff at 95th percentile, with 5% of measurements above the value, and 95% of measurements below the value. This is also known as Burstable billing Line speed is measured in bits per second (or kilobits per second, megabits per second or gigabits per second). Unmetered method: The second bandwidth measurement is unmetered service where providers cap or control the “top line” speed for a server. Top line speed in unmetered bandwidth is the total Mbit/s allocated to the server and configured on the switch level. For example, if you purchase 10 Mbit/s unmetered bandwidth, the top line speed would be 10 Mbit/s. 10 Mbit/s would result in the provider controlling the speed transfers take place while providing the ability for the dedicated server owner to not be charged with bandwidth overages. Unmetered bandwidth services usually incur an additional charge. Total transfer method: Some providers will calculate the Total Transfer, which is the measurement of actual data leaving and arriving, measured in bytes. Although it is typically the sum of all traffic into and out of the server, some providers measure only outbound traffic (traffic from the server to the internet). Bandwidth pooling: This is a key mechanism for hosting buyers to determine which provider is offering the right pricing mechanism of bandwidth pricing.[according to whom?] Most Dedicated Hosting providers bundle bandwidth pricing along with the monthly charge for the dedicated server. Let us illustrate this with the help of an example. An average $100 server from any of the common dedicated bandwidth providers would carry 2 TB of bandwidth. Suppose you purchased 10 servers then you would have the ability to consume 2 TB of bandwidth per server. However, let us assume that given your application architecture only 2 of these 10 servers are really web facing while the rest are used for storage, search, database or other internal functions then the provider that allows bandwidth pooling would let you consume overall 20 TB of bandwidth as incoming or outbound or both depending on their policy. The provider that does not offer bandwidth pooling would just let you use 4 TB of bandwidth, and the rest of the 16 TB of bandwidth would be practically unusable. This fact is commonly known by all hosting providers, and allows hosting providers to cut costs by offering an amount of bandwidth that frequently will not be used. This is known as overselling, and allows high bandwidth customers to use more than what a host might otherwise offer, because they know that this will be balanced out by those customers who use less than the maximum allowed. One of the reasons for choosing to outsource dedicated servers is the availability of high powered networks from multiple providers. As dedicated server providers utilize massive amounts of bandwidth, they are able to secure lower volume based pricing to include a multi-provider blend of bandwidth. To achieve the same type of network without a multi-provider blend of bandwidth, a large investment in core routers, long term contracts, and expensive monthly bills would need to be in place. The expenses needed to develop a network without a multi-provider blend of bandwidth does not make sense economically for hosting providers. Many dedicated server providers include a service level agreement based on network uptime. Some dedicated server hosting providers offer a 100% uptime guarantee on their network. By securing multiple vendors for connectivity and using redundant hardware, providers are able to guarantee higher uptimes; usually between 99-100% uptime if they are a higher quality provider. One aspect of higher quality providers is they are most likely to be multi-homed across multiple quality uplink providers, which in turn, provides significant redundancy in the event one goes down in addition to potentially improved routes to destinations. Bandwidth consumption over the last several years has shifted from a per megabit usage model to a per gigabyte usage model. Bandwidth was traditionally measured in line speed access that included the ability to purchase needed megabits at a given monthly cost. As the shared hosting model developed, the trend towards gigabyte or total bytes transferred, replaced the megabit line speed model so dedicated server providers started offering per gigabyte. Prominent players in the dedicated server market offer large amounts of bandwidth ranging from 500 gigabytes to 3000 gigabytes using the “overselling” model. It is not uncommon for major players to provide dedicated servers with 1Terabyte (TB) of bandwidth or higher. Usage models based on the byte level measurement usually include a given amount of bandwidth with each server and a price per gigabyte after a certain threshold has been reached. Expect to pay additional fees for bandwidth overage usage. For example, if a dedicated server has been given 3000 gigabytes of bandwidth per month and the customer uses 5000 gigabytes of bandwidth within the billing period, the additional 2000 gigabytes of bandwidth will be invoiced as bandwidth overage. Each provider has a different model for billing. As of yet, no industry standards have been set.Management
Main article: Managed dedicated server
Dedicated hosting services primarily differ from managed hosting services in that managed hosting services usually offer more support and other services. As such, managed hosting is targeted towards clients with less technical knowledge, whereas dedicated hosting services, or unmanaged hosting services, are suitable for web development and system administrator professionals.[3]
To date, no industry standards have been set to clearly define the management role of dedicated server providers. What this means is that each provider will use industry standard terms, but each provider will define them differently. For some dedicated server providers, fully managed is defined as having a web based control panel while other providers define it as having dedicated system engineers readily available to handle all server and network related functions of the dedicated server provider.
Server management can include some or all of the following:
- Operating system updates
- Application updates
- Server monitoring
- SNMP hardware monitoring
- Application monitoring
- Application management
- Technical support
- Firewall services
- Anti-spam software
- Antivirus updates
- Security audits
- DDoS protection and mitigation
- Intrusion detection
- Backups and restoration
- Disaster recovery
- DNS hosting service
- Load balancing
- Database administration
- Performance tuning
- Software installation and configuration
- User management
- Programming consultation
- Fully managed - Includes monitoring, software updates, reboots, security patches and operating system upgrades. Customers are completely hands-off.
- Managed - Includes medium level of management, monitoring, updates, and a limited amount of support. Customers may perform specific tasks.
- Self-managed - Includes regular monitoring and some maintenance. Customers provide most operations and tasks on dedicated server.
- Unmanaged - Little to no involvement from service provider. Customers provide all maintenance, upgrades, patches, and security.
Security
Dedicated hosting server providers utilize extreme security measures to ensure the safety of data stored on their network of servers. Providers will often deploy various software programs for scanning systems and networks for obtrusive invaders, spammers, hackers, and other harmful problems such as Trojans, worms, and crashers (Sending multiple connections). Linux and Windows use different software for security protection.Software
Providers often bill for dedicated servers on a fixed monthly price to include specific software packages. Over the years, software vendors realized the significant market opportunity to bundle their software with dedicated servers. They have since started introducing pricing models that allow dedicated hosting providers the ability to purchase and resell software based on reduced monthly fees. Microsoft offers software licenses through a program called the Service Provider License Agreement. The SPLA model provides use of Microsoft products through a monthly user or processor based fee. SPLA software includes the Windows Operating System, Microsoft SQL Server, Microsoft Exchange Server, Microsoft SharePoint and shoutcast hosting, and many other server based products. Dedicated server providers usually offer the ability to select the software you want installed on a dedicated server. Depending on the overall usage of the server, this will include your choice of operating system, database, and specific applications. Servers can be customized and tailored specific to the customer’s needs and requirements. Other software applications available are specialized web hosting specific programs called control panels. Control panel software is an all inclusive set of software applications, server applications, and automation tools that can be installed on a dedicated server. Control panels include integration into web servers, database applications, programming languages, application deployment, server administration tasks, and include the ability to automate tasks via a web based front end. Most dedicated servers are packaged with a control panel. Control panels are often confused with management tools, but these control panels are actually web based automation tools created to help automate the process of web site creation and server management. Control panels should not be confused with a full server management solution by a dedicated hosting provider.Limitations
Many providers do not allow IRC (bots, clients or daemons). This is due to rogue IRC users triggering DDoS attacks against the provider, which may overwhelm their networks, lowering service quality for all customers.[4][citation needed]- Adult content is disallowed by many providers as it may either be of questionable legality or consume large amounts of bandwidth.
- Copyright violations - Hosting copyrighted material of which an individual does not own the copyright to is against the terms of service of most hosting companies.
Types of Website Hosting
If you're interested in creating an online presence for yourself or your business, the best way to do it is to build a website. Websites are, most basically, collections of files, so each one requires a place to store its files and a way to make those files accessible to other people connected to the internet. A web server, through web hosting, performs these critical functions. While every site needs hosting, there are a number of different ways that website hosting can be done. Which type of hosting will work best for your site depends on its size and complexity, as well as the resources and technical expertise at your disposal. To help you figure out the best hosting match for you, we'll take you through some of the most popular website hosting options below.
Shared Website Hosting
Shared hosting, also called virtual hosting, is the hosting of multiple websites on the same web server. With shared hosting, a web hosting company provides the user storage space and makes the website's files accessible to others via the internet. The web host also maintains the server and provides technical support for it. For those who are not technically inclined or who do not have access to their own technical support staff, having a web host to manage these matters can make shared hosting can make a great fit.
Perhaps the greatest advantage of shared hosting is that its efficient use of resources means that it costs much less than most other types of website hosting. Shared web hosting also means that users can benefit from the expertise of the web hosting company providing the servers; a web hosting company like Freeservers that specializes in shared hosting has the experience and resources to provide exceptional reliability and technical support for your site. The specialized resources of a shared hosting company are well positioned to keep your site running properly and serving quickly at all times.
While shared hosting is an appropriate choice for many users, it's not right for everyone. Those with extensive technical know-how who want complete control over their servers and websites are better served by another hosting option. Additionally, if your site is large and extremely active, you may need more server resources than shared hosting provides.
Dedicated Website Hosting
With dedicated web hosting, there is a web server devoted entirely to your site. You may purchase your own server or pay for access to a server owned by someone else. If you own your own server and have it stored in someone else's facility, you are using what is known as colocation hosting. In any type of dedicated hosting, because the server is exclusively dedicated to your site, you will have full control over its use and administration. This allows you to manage all aspects of your site. If your intent is to create a large site for a company with plenty of technical and financial resources, dedicated hosting might be right for you. If your site will demand a lot of server space and bandwidth, too, you may need a dedicated server to host it.
For individuals and small or midsized companies, however, there are a number of aspects of dedicated hosting that make it a less desirable option. Setting up or leasing and maintaining your own web server requires a great deal of technical expertise as well as a significant financial investment. Because the web server you use will determine whether your site is reliably online and available to visitors, you need to be certain that your server is stable, reliable, well maintained, and able to handle heavy visitor traffic; maintaining this level of performance is not always easy.
Virtual Private Server Website Hosting
This type of hosting is something of a cross between dedicated hosting and shared hosting. Virtual private server hosting involves a dedicated server being shared by multiple users. The users share the resources of the server, but the server space is strictly divided into allocated percentages so that each user's percentage of the server is dedicated only to that user's website. This hosting arrangement gives a user some of the control of a dedicated server without the large-scale investment in a server that may have more space than necessary. Virtual private server hosting does provide limited resources, however, and even if your site experiences a temporary traffic spike or another unusual demand, there will not be extra resources flexibly available to meet the need. The somewhat complicated arrangements of virtual private server hosting can also be a drawback to this hosting option, as service providers can create confusing service agreements that include unexpected limitations for their users.
Shared Website Hosting with Freeservers
Now that you've learned about your hosting options, perhaps you've decided that shared hosting is right for your website. When you're ready to create your shared hosting account, start by comparing the web hosting packages Freeservers offers. We provide a variety of packages, from free web hosting to feature-rich business hosting packages, so you're sure to find one that fits your needs. With Freeservers, you'll receive top-notch hosting services and loads of useful features, all with the exceptional reliability, stability, and customer support that you need to make your website a success.
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