Saturday, March 10, 2007

Shared web hosting service

A shared web hosting service or virtual hosting service is a form of web hosting service where more than one instance of the same web service is hosted on a single physical server. This is generally the most economical option for hosting as many people share the overall cost of server maintenance.

The hosting service must include system administration since it is shared by many users; this is a benefit for users who do not want to deal with it, but a hindrance to power users who want more control.
Shared hosting typically uses a web-based control panel system, such as cPanel, DirectAdmin, Plesk, Helm, H-sphere, Ensim, Sphera or one of many other control panel products. Control panels and web interfaces have been causing some controversy lately as claims that it holds patent rights to the hosting technology with its 19 patents. Hostopia, a large wholesale host, recently purchased a license to use that technology from for 10% of retail revenues. recently sued Godaddy as well for similar patent infringement.
In shared hosting, the provider is generally responsible for management of servers, installation of server software, security updates and other aspects of the service. The majority of servers are based on the Linux operating system, but some providers offer Microsoft Windows-based or FreeBSD-based solutions. For example, the Plesk and Ensim control panels are both available for two operating systems, Linux and Windows. Versions for either OS have very similar interfaces and functionality, with the exception of OS-specific differences (for example, ASP.NET or Microsoft SQL Server support under Windows).
There are thousands of shared hosting providers in the United States alone. They range from mom-and-pop shops and small design firms to multi-million-dollar providers with hundreds of thousands of customers. A large portion of the shared web hosting market is driven through Pay Per Click advertising (PPC) or Affiliate programs.
Shared web hosting can also be done privately by sharing the cost of running a server in a colocation centre; this is called cooperative hosting.

Free web hosting service

A free web hosting service is a web hosting service that is free, usually advertisement-supported and of limited functionality. Free web hosts will either provide a subdomain ( (e.g. 50megs, Byethost, Netfirms) or a directory ( (e.g. GeoCities). In contrast, paid web hosts will usually provide a Second-level domain along with the hosting ( Some free hosts do allow use of separately-purchased domains. Rarely, a free host may also operate as a domain name registrar, but their registry services are usually more expensive than others.

A few free web hosts have a basic package for free (e.g. Freewebs), and enhanced packages (with more features) for a cost. This allows users to try the service for an initial trial (see how it performs compared to other hosts), and then upgrade when (and if) needed.

Free hosting may have the following limitations:
--Limitation on the size of each hosted file
--Very small bandwidth per month compared to paid hosting
--Prevents hotlinking of files
--Do not allow certain file types (for example MP3, MPEG, ZIP etc.)
--Compulsory placement of the Webhosts' Banner or Popup ads into all web pages
--Do not provide any uptime guarantee

Some free host may provide these extra features:
--A web based control panel
--File transfer via FTP
--Scripting languages: PHP, ASP, Perl etc.
--Relational databases such as MySQL
--Scheduled processes, known as cronjobs
--Free email accounts for the domain or subdomain hosted
--Other features such as guestbooks (e.g. Bravenet)

Obtaining hosting

Web hosting is often provided as part of a general Internet access plan; there are many free and paid providers offering these services.

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.

Web hosting packages often include a Web Content Management System, so the end-user doesn't have to worry about the more technical aspects.

Types of hosting

Internet hosting services can run Web servers; see Internet hosting services.

Hosting services limited to the Web:
--Free web hosting service: is free, (sometimes) advertisement-supported web hosting, and is extremely limited when compared to paid hosting.
--Shared web hosting service: one's Web site 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.
--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 provider.
--Virtual Dedicated Server: slicing up a server into virtual servers. each user feels like they're on their own dedicated server, but they're actually sharing a server with many other users.
--Dedicated hosting service: the user gets his or her own Web server and gains full control over it (root access for Linux/administrator access for Windows); however, the user typically does not own the server.
--Colocation web hosting service: similar to the dedicated web hosting service, but the user owns the 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 the 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.
--Clustered hosting: having multiple servers hosting the same content for better resource utilization. Wikipedia's own servers are a good example of this.

Some specific Web services:
--File hosting service: hosts not web pages but files
--Image hosting service
--Video hosting service
--Blog hosting service
--One-click hosting
--Shopping cart software

Hosting reliability and uptime

Hosting uptime refers to the percentage of time the host is accessible via the internet. Many hosting providers state that they aim for a 99.9% uptime, but there may be server restarts and planned (or unplanned) maintenance in any web hosting environment.

A popular claim from the popular hosting providers is '99% or 99.9% server uptime' but this often refers only to a server being powered on and doesn't account for network downtime. Real downtime can potentially be larger than the percentage guaranteed by the hosting provider. Many providers tie uptime, and accessibility, into their own Service Level Agreement, or SLA. SLAs may or may not include refunds, or reduced costs if performance goals are not met.

Service scope

The scopes of hosting services vary widely. The most basic is webpage and small-scale file hosting, where files can be uploaded via File Transfer Protocol (FTP) or a Web interface. The files are usually delivered to the Web "as is" or with little processing. Many Internet service providers (ISPs) offer this service for free to their subscribers. People can also obtain Web page hosting from other, alternative service providers. Web page hosting is typically free, advertisement-sponsored, or cheap.
Web page hosting is generally sufficient only for personal web pages. A complex site calls for a more comprehensive package that provides database support and application development platforms (e.g. PHP, Java, and ASP.NET). These facilities allow the customers to write or install scripts for applications like forums and content management. For e-commerce, SSL is also required.
The host may also provide a Web interface control panel (e.g. cPanel, Hosting Controller, Plesk or View a list of Control panels) for managing the Web server and installing scripts as well as other services like e-mail. Control panels and web interfaces have been causing some controversy lately as claims that it holds patent rights to the hosting technology with its 19 patents. Hostopia, a large wholesale host, recently purchased a license to use that technology from for 10% of retail revenues. recently sued Go Daddy as well for similar patent infringement.
Some hosts specialize in certain software or services (e.g. e-commerce). They are commonly used by larger companies to outsource network infrastructure to a hosting company. To find a web hosting company, there are searchable directories that can be used.