Monday, June 29, 2015

Drupal,content-management framework,GNU General Public License,taxonomy,RSS feeds,menu management,MySQL, MongoDB, MariaDB, PostgreSQL, SQLite, or Microsoft SQL Server

Drupal is a free and open-source content-management framework written in PHP and distributed under the GNU General Public License. It is used as a back-end framework for at least 2.1% of all Web sites worldwide ranging from personal blogs to corporate, political, and government sites including WhiteHouse.gov and data.gov.uk.It is also used for knowledge management and business collaboration.

The standard release of Drupal, known as Drupal core, contains basic features common to content management systems. These include user account registration and maintenance, menu management, RSS feeds, taxonomy, page layout customization, and system administration. The Drupal core installation can serve as a simple Web site, a single- or multi-user blog, an Internet forum, or a community Web site providing for user-generated content.

As of April 2015, there are more than 30,000 free community-contributed addons, known as contributed modules, available to alter and extend Drupal's core capabilities and add new features or customize Drupal's behavior and appearance. The Drupal community has more than 1 million members (as of October 2013) and 31,000 Developers (as of February 2014). Because of this plug-in extensibility and modular design, "The Drupal Overview" on Drupal's Web site describes it as a content management framework. Drupal is also described as a Web application framework, as it meets the generally accepted feature requirements for such frameworks.

Although Drupal offers a sophisticated programming interface for developers, basic Web site installation and administration of the framework requires no programming skills.

Drupal runs on any computing platform that supports both a Web server capable of running PHP (including Apache, LiteSpeed, IIS, Lighttpd, Hiawatha, Cherokee or Nginx) and a database (such as MySQL, MongoDB, MariaDB, PostgreSQL, SQLite, or Microsoft SQL Server) to store content and settings.

Friday, June 26, 2015

DNS proxy ,Internet Domain Name Server,DNS records

A DNS proxy server takes DNS queries from a (usually local) network and forwards them to an Internet Domain Name Server. It may also cache DNS records.

Tuesday, June 23, 2015

DNS and Name Servers,IP number,Name Server,hosting provider

DNS stands for "Domain Name System." The domain name system acts like a large telephone directory and in that it's the master database, which associates a domain name such as www.wikipedia.org with the appropriate IP number. Consider the IP number something similar to a phone number: When someone calls www.wikipedia.org, the ISP looks at the DNS server, and asks "how do I contact www.wikipedia.org?" The DNS server responds, for example, "it can be found at: 216.198.221.66.". As the Internet understands it, this can be considered the phone number for the server, which houses the web site. When the domain name is registered/purchased on a particular registrar's "name server", the DNS settings are kept on their server, and in most cases point the domain to the Name Server of your hosting provider. This Name Server is where the IP number (currently associated with your domain name) resides.

Friday, June 19, 2015

cPanel ,web hosting,administrators,resellers, end-user,CentOS,Red Hat Enterprise Linux (RHEL),CloudLinux

cPanel is a Linux based web hosting control panel that provides a graphical interface and automation tools designed to simplify the process of hosting a web site. cPanel utilizes a 3 tier structure that provides capabilities for administrators, resellers, and end-user website owners to control the various aspects of website and server administration through a standard web browser.

In addition to the GUI, cPanel also has command line and API-based access that allows third party software vendors, web hosting organizations, and developers to automate standard system administration processes.

cPanel is designed to function either as a dedicated server or virtual private server. The latest cPanel version supports installation on CentOS, Red Hat Enterprise Linux (RHEL), and CloudLinux.cPanel 11.30 is the last major version to support FreeBSD.

Application-based support includes Apache, PHP, MySQL, PostgreSQL, Perl, and BIND (DNS). Email based support includes POP3, IMAP, SMTP services. cPanel is accessed via https on port 2083.

Once installed, cPanel cannot be easily removed. cPanel's FAQ states that the best way to uninstall cPanel is by reformating the server.However, uninstall guides are available online for expert server administrators who do not wish to reformat their server. Similarly, it should only be installed on a freshly installed operating system with minimal prior configuration.

Tuesday, June 16, 2015

Cloud computing_Software as a service (SaaS),application software,databases,on-demand software,

In the business model using software as a service (SaaS), users are provided access to application software and databases. Cloud providers manage the infrastructure and platforms that run the applications. SaaS is sometimes referred to as "on-demand software" and is usually priced on a pay-per-use basis or using a subscription fee.

In the SaaS model, cloud providers install and operate application software in the cloud and cloud users access the software from cloud clients. Cloud users do not manage the cloud infrastructure and platform where the application runs. This eliminates the need to install and run the application on the cloud user's own computers, which simplifies maintenance and support. Cloud applications are different from other applications in their scalability.which can be achieved by cloning tasks onto multiple virtual machines at run-time to meet changing work demand. Load balancers distribute the work over the set of virtual machines. This process is transparent 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.

The pricing model for SaaS applications is typically a monthly or yearly flat fee per user, so price is scalable and adjustable if users are added or removed at any point.

Proponents claim SaaS allows a business the potential to reduce IT operational costs by outsourcing hardware and software maintenance and support to the cloud provider. This enables the business to reallocate IT operations costs away from hardware/software spending and personnel expenses, towards meeting other goals. In addition, with applications hosted centrally, updates can be released without the need for users to install new software. One drawback of SaaS is that the users' data are stored on the cloud provider's server. As a result, there could be unauthorized access to the data. For this reason, users are increasingly adopting intelligent third-party key management systems to help secure their data.

Saturday, June 13, 2015

Cloud computing_Platform as a service,programming language,computing platform,Google App Engine

In the PaaS models, 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 like Microsoft Azure and Google App Engine, the underlying computer and storage resources scale automatically to match application demand so that the cloud user does not have to allocate resources manually. The latter has also been proposed by an architecture aiming to facilitate real-time in cloud environments.Even more specific application types can be provided via PaaS, e.g., such as media encoding as provided by services as bitcodin transcoding cloud or media.io.

Tuesday, June 9, 2015

Cloud computing_Infrastructure as a service,Xen, Oracle VirtualBox, KVM, VMware ESX/ESXi,Hyper-V,virtual machines

In the most basic cloud-service model & according to the IETF (Internet Engineering Task Force), providers of IaaS offer computers ? physical or (more often) virtual machines ? and other resources. (A hypervisor, such as Xen, Oracle VirtualBox, KVM, VMware ESX/ESXi, or Hyper-V runs the virtual machines as guests. Pools of hypervisors within the cloud operational support-system can support large numbers of virtual machines and the ability to scale services up and down according to customers' varying requirements.) IaaS clouds often offer additional resources such as a virtual-machine disk image library, raw block storage, and file or object storage, firewalls, load balancers, IP addresses, virtual local area networks (VLANs), and software bundles.IaaS-cloud providers supply these resources on-demand from their large pools installed in data centers. For wide-area connectivity, customers can use either the Internet or carrier clouds (dedicated virtual private networks).

To deploy their applications, cloud users install operating-system images and their application software on the cloud infrastructure. In this model, the cloud user patches and maintains the operating systems and the application software. Cloud providers typically bill IaaS services on a utility computing basis: cost reflects the amount of resources allocated and consumed.

Saturday, June 6, 2015

Cloud computing, metaphor,computer resources,utility

Cloud computing is a computing term or metaphor that evolved in the late 1990s, based on utility and consumption of computer resources. Cloud computing involves application systems which are executed within the cloud and operated through internet enabled devices. Purely cloud computing does not rely on the use of cloud storage as it will be removed upon users download action. Clouds can be classified as public, private and hybrid.

Wednesday, June 3, 2015

Apache HTTP Server, Apache,web server,NCSA,Unix-like system,NetWare,FreeBSD

The Apache HTTP Server, colloquially called Apache, is the world's most widely used web server software. Originally based on the NCSA HTTPd server, development of Apache began in early 1995 after work on the NCSA code stalled. Apache played a key role in the initial growth of the World Wide Web,quickly overtaking NCSA HTTPd as the dominant HTTP server, and has remained the most popular HTTP server since April 1996. In 2009, it became the first web server software to serve more than 100 million websites.

Apache is developed and maintained by an open community of developers under the auspices of the Apache Software Foundation. Most commonly used on a Unix-like system (usually Linux),the software is available for a wide variety of operating systems, including Windows, OS X, Linux, Unix, FreeBSD, Solaris, NetWare, OS/2, TPF, OpenVMS and eComStation. Released under the Apache License, Apache is free and open-source software.

As of June 2013, Apache was estimated to serve 54.2% of all active website and 53.3% of the top servers across all domains.