Welcome to SvenSoft

Welcome to SvenSoft !

We are happy to introduce ourselves today as a Software and IT Services company with corporate headquarters at Faridabad near Delhi, India (NCR). We provide and implement end-to-end IT solutions for all your needs at very affordable prices. Even if you have an in-house software development center, we can definitely lower your costs while at the same time boosting software quality. We combine our software expertise with our focus on understanding the business domain to conceptualize, design and develop sophisticated and high quality, innovative e-business solutions such as tailor-made Websites, fully functional commercial web applications, custom software and dynamic business process automation (BPA) tools.

We also provide associated consulting services to help you assess which software solution will best serve your needs in the given business context. In addition, we also configure and fine tune your hardware as well to work optimally in tandem with the software we develop which helps you wring the maximum performance from your overall IT investment..

Clientele:

We have worked with some of the leading companies in the USA such as Walgreens Co. (Ranked #40 in Fortune 500 2008 List. Read more at: money.cnn.com/magazines/fortune/fortune500/2008/snapshots/2275.html), and are aggressively expanding our operations in India. You can read more about us at http://www.svensoft.com/SvenSoft/about

IT Services We Provide:

Some of the IT Services we provide are:

• Web Development
• Full Cycle Custom Application Development
• Consulting Services
• Application Management
• Migration and re-engineering
• Performance Engineering
• Database Management and Optimization

You can read more about the services we provide at http://www.svensoft.com/SvenSoft/services

Web Development – A Special Focus:

Although we work with a host of different technologies as per client needs, one of our major areas of expertise is developing Web based systems/websites for both intranet and internet applications using Java/J2EE technologies.

• Cross browser compliant
• Adoption of Usability Principles in interface design for clean and intuitive interface
• Expertise in Web 2.0/AJAX enabled web apps.
• Expertise with all front-end technologies like HTML, DHTML, CSS, JavaScript (jQuery, etc.).
• Expertise in middleware/backend technologies (application servers/databases such as IBM WebSphere, Weblogic/ Oracle) for fully functional web applications.
• Significant expertise with and use of Open Source technologies (Apache, MySql, etc.).
• Assistance with all other aspects such as domain name registration, selecting a hosting provider, developing in-house hosting, etc.
  

You can read more about our web development services at
http://www.svensoft.com/SvenSoft/services

E-Commerce Initiative - Xatori.com:

We have recently launched a service (in beta phase currently) which will serve to establish baseline prices for common consumer goods. It is an e-commerce price comparison website
Xatori.com, and has been developed for the US market using web services from Amazon, eBay and Yahoo. Its’ a fully Web 2.0 enabled AJAX based website with a Java/J2EE back-end. We developed it using an in-house framework since none of the frameworks out there satisfied our cutting-edge requirements. I encourage you to visit the site at http://www.xatori.com.

Our Philosophy - Customer is First:

We know that each and every customer is unique and has different needs. That is why we work closely with our clients and provide development services tailored to their needs. We go above and beyond Service Level Agreements, contract terms, etc. - to actually help you solve your problems and achieve your objectives - whatever it takes. We don't just provide software, we provide solutions.

Our development methodology represents a powerful combination of the best industry-proven practices and leading standards, and is focused on streamlining the development process to increase return on investment (ROI) and compress time-to-market. Our methodology is applied successfully to medium- to large-scale custom application development projects. You can read more about it at http://www.svensoft.com/SvenSoft/process

Contact Us

Company Name	:	SvenSoft Technologies
Company Address	:	173 Sector 17, Faridabad (Haryana), PIN - 121002, India
Phone/Fax	:	91-129-4075173
Mobile No.	:	91-9910597320
E Mail ID	:	contact@svensoft.com
Website (if any)	:	http://www.svensoft.com

Grid computing

Grid computing is a term for either of two broad subcategories of distributed computing:
Online computation or storage offered as a service supported by a pool of distributed computing resources, also known as utility computing, on-demand computing, or cloud computing. Data grids provide controlled sharing and management of large amounts of distributed data, often used in combination with computational grids.

The creation of a "virtual supercomputer" composed of a network of loosely-coupled computers, acting in concert to perform very large tasks. This technology has been applied to computationally-intensive scientific, mathematical, and academic problems through volunteer computing, and it is used in commercial enterprises for such diverse applications as drug discovery, economic forecasting, seismic analysis, and back-office data processing in support of e-commerce and web services.

What distinguishes grid computing from typical cluster computing systems is that grids tend to be more loosely coupled, heterogeneous, and geographically dispersed. Also, while a computing grid may be dedicated to a specialized application, it is often constructed with the aid of general purpose grid software libraries and middleware.

Grids versus conventional supercomputers

"Distributed" or "grid" computing in general is a special type of parallel computing which relies on complete computers (with onboard CPU, storage, power supply, network interface, etc.) connected to a network (private, public or the Internet) by a conventional network interface, such as Ethernet. This is in contrast to the traditional notion of a supercomputer, which has many processors connected by a local high-speed computer bus.

The primary advantage of distributed computing is that each node can be purchased as commodity hardware, which when combined can produce similar computing resources to a multiprocessor supercomputer, but at lower cost. This is due to the economies of scale of producing commodity hardware, compared to the lower efficiency of designing and constructing a small number of custom supercomputers. The primary performance disadvantage is that the various processors and local storage areas do not have high-speed connections. This arrangement is thus well-suited to applications in which multiple parallel computations can take place independently, without the need to communicate intermediate results between processors.
The high-end scalability of geographically dispersed grids is generally favorable, due to the low need for connectivity between nodes relative to the capacity of the public Internet. Conventional supercomputers also create physical challenges in supplying sufficient electricity and cooling capacity in a single location. Both supercomputers and grids can be used to run multiple parallel computations at the same time, which might be different simulations for the same project, or computations for completely different applications. The infrastructure and programming considerations needed to do this on each type of platform are different, however.

There are also some differences in programming and deployment. It can be costly and difficult to write programs so that they can be run in the environment of a supercomputer, which may have a custom operating system, or require the program to address concurrency issues. If a problem can be adequately parallelized, a "thin" layer of "grid" infrastructure can allow conventional, standalone programs to run on multiple machines (but each given a different part of the same problem). This makes it possible to write and debug programs on a single conventional machine, and eliminates complications due to multiple instances of the same program running in the same shared memory and storage space at the same time.

Design considerations and variations

One feature of distributed grids is that they can be formed from computing resources belonging to multiple individuals or organizations (known as multiple administrative domains). This can facilitate commercial transactions, as in utility computing, or make it easier to assemble volunteer computing networks.

One disadvantage of this feature is that the computers which are actually performing the calculations might not be entirely trustworthy. The designers of the system must thus introduce measures to prevent malfunctions or malicious participants from producing false, misleading, or erroneous results, and from using the system as an attack vector. This often involves assigning work randomly to different nodes (presumably with different owners) and checking that at least two different nodes report the same answer for a given work unit. Discrepancies would identify malfunctioning and malicious nodes.

Due to the lack of central control over the hardware, there is no way to guarantee that nodes will not drop out of the network at random times. Some nodes (like laptops or dialup Internet customers) may also be available for computation but not network communications for unpredictable periods. These variations can be accommodated by assigning large work units (thus reducing the need for continuous network connectivity) and reassigning work units when a given node fails to report its results as expected.

The impacts of trust and availability on performance and development difficulty can influence the choice of whether to deploy onto a dedicated computer cluster, to idle machines internal to the developing organization, or to an open external network of volunteers or contractors.
In many cases, the participating nodes must trust the central system not to abuse the access that is being granted, by interfering with the operation of other programs, mangling stored information, transmitting private data, or creating new security holes. Other systems employ measures to reduce the amount of trust "client" nodes must place in the central system such as placing applications in virtual machines.

Public systems or those crossing administrative domains (including different departments in the same organization) often result in the need to run on heterogeneous systems, using different operating systems and hardware architectures. With many languages, there is a tradeoff between investment in software development and the number of platforms that can be supported (and thus the size of the resulting network). Cross-platform languages can reduce the need to make this tradeoff, though potentially at the expense of high performance on any given node (due to run-time interpretation or lack of optimization for the particular platform).

Various middleware projects have created generic infrastructure, to allow diverse scientific and commercial projects to harness a particular associated grid, or for the purpose of setting up new grids. BOINC is a common one for academic projects seeking public volunteers; more are listed at the end of the article.

In fact, the middleware can be seen as a layer between the hardware and the software. On top of the middleware, a number of technical areas have to be considered, and these may or may not be middleware independent. Example areas include SLA management, Trust and Security, VO (virtual Organization) management, License Management, Portals and Data Management. These techniocal areas may be taken care of in a commercial solution, though the cutting edge of each area is often found within specific research projects examining the field.

CPU scavenging
CPU-scavenging, cycle-scavenging, cycle stealing, or shared computing creates a "grid" from the unused resources in a network of participants (whether worldwide or internal to an organization). Typically this technique uses desktop computer instruction cycles that would otherwise be wasted at night, during lunch, or even in the scattered seconds throughout the day when the computer is waiting for user input or slow devices.

Volunteer computing projects use the CPU scavenging model almost exclusively.
In practice, participating computers also donate some supporting amount of disk storage space, RAM, and network bandwidth, in addition to raw CPU power. Since nodes are apt to go "offline" from time to time, as their owners use their resources for their primary purpose, this model must be designed to handle such contingencies.

History
The term Grid computing originated in the early 1990s as a metaphor for making computer power as easy to access as an electric power grid in Ian Foster and Carl Kesselmans seminal work, "The Grid: Blueprint for a new computing infrastructure".
CPU scavenging and volunteer computing were popularized beginning in 1997 by distributed.net and later in 1999 by SETI@home to harness the power of networked PCs worldwide, in order to solve CPU-intensive research problems.

The ideas of the grid (including those from distributed computing, object oriented programming, cluster computing, web services and others) were brought together by Ian Foster, Carl Kesselman and Steve Tuecke, widely regarded as the "fathers of the grid." They led the effort to create the Globus Toolkit incorporating not just computation management but also storage management, security provisioning, data movement, monitoring and a toolkit for developing additional services based on the same infrastructure including agreement negotiation, notification mechanisms, trigger services and information aggregation. While the Globus Toolkit remains the defacto standard for building grid solutions, a number of other tools have been built that answer some subset of services needed to create an enterprise or global grid.

During 2006 the term "Great Global Grid" was coined by Robert Marcus in his book "Emerging Technology Strategies". Many organizations working on grid computing name their servers "ggg..com" as an analogy to the "www..com" naming convention of the World Wide Web

During 2007 the term cloud computing came into popularity. It is conceptually identical to the canonical Foster definition of grid computing below.In practice all clouds are grids, but not all grids manage a cloud.

National Grid Projects
D-Grid (German)
Grid5000 (French)
GARUDA (Indian)
National Grid Service (UK)
Open Science Grid (USA)
VECC (Calcutta, India)
China Grid Project
INFN Grid (Italian)
KnowledgeGrid Malaysia
NAREGI Project
Singapore National Grid Project
Thai National Grid Project
LitGRID (Lithuanian)
EestiGrid (Estonia

Hellasgrid (Greek)
Swiss National Grid Association
Swegrid (Swedish National computational resource)
RDIG - Russian Data Intensive Grid
NorGrid - Norwegian Grid Initiative
Rogrid - Romanian Grid Initiative
Austrian Grid - Austrian Grid Initiative
TR-Grid - Turkish National Grid Initiative

Clustered hosting

Clustered hosting technology is designed to eliminate the problems inherent with typical shared hosting infrastructures. This technology provides customers with a “clustered” handling of security, load balancing, and necessary website resources.
A clustered hosting platform is data-driven, which means that no human interaction is needed to provision a new account to the platform.

Clustered hosting "virtualizes" the resources beyond the limits of one physical server, and as a result, a website is not limited to one server. They share the processing power of many servers and their applications are distributed in real-time. This means that they can purchase as much computing power as they want from a virtually inexhaustible source, since even the largest customer never consumes more than a fraction of a percent of the total server pool. Customer account changes (to add new resources or change settings) are propagated immediately to every server in the cluster. This is different from typical shared hosting architectures that usually require changes to a configuration file that becomes live after the server is rebooted during off hours, or are pushed on a cyclic basis every few hours.

Multiple tiers of security are integrated into the clustered hosting platform. In a typical hosting environment, the security layer is usually not integrated in the platform. The stock solutions used for shared hosting do not solve core issues around integrating security between the application and the operating system. At best, most typical hosts will implement a firewall solution, and weaknesses inherent with the operating system will remain exploitable to those that penetrate the firewall.

Clustered hosting network layer protections employ intelligent routing, redundant switching fabric and built in firewall and proxy technology. Clustered hosting provides considerable advantages over traditional hosting architectures in mitigating denial-of-service attacks and other network attacks because such attacks can be dispersed over a large pool of servers, and if individual hardware components are impacted by such attacks, they automatically fall out of traffic handling during the attack.

See also
High-availability cluster
Enomalism Clustered Hosting Platform LGPL

Source: http://en.wikipedia.org/wiki/Clustered_hosting

Web Hosting Company

Colocation centre

A colocation centre (collocation center) ("colo") or carrier hotel is a type of data center where multiple customers locate network, server and storage gear and interconnect to a variety of telecommunications and other network service provider(s) with a minimum of cost and complexity.

Increasingly organizations are recognizing the benefits of colocating their mission-critical equipment within a data centre. Colocation is becoming popular because of the time and cost savings a company can realize as result of using shared data centre infrastructure. Significant benefits of scale (large power and mechanical systems) result in large colocation facilities, typically 4500 to 9500 square metres (roughly 50000 to 100000 square feet). With IT and communications facilities in safe, secure hands, telecommunications, internet, ASP and content providers, as well as enterprises, enjoy less latency and the freedom to focus on their core business.

Additionally, customers reduce their traffic back-haul costs and free up their internal networks for other uses. Moreover, by outsourcing network traffic to a colocation service provider with greater bandwidth capacity, web site access speeds should improve considerably.

Major types of colocation customers are:

Web commerce companies, who use the facilities for a safe environment and cost-effective, redundant connections to the Internet
Major enterprises, who use the facility for disaster avoidance, offsite data backup and business continuity

Telecommunication companies, who use the facilities to interexchange traffic with other telecommunications companies and access to potential clients
Most network access point facilities provide colocation.

Building

Fire protection systems, including passive and active active design elements, as well as implementation of fire prevention programs in operations. Smoke detectors are usually installed to provide early warning of a developing fire by detecting particles generated by smoldering components prior to the development of flame. This allows investigation, interruption of power, and manual fire suppression using hand held fire extinguishers before the fire grows to a large size. A fire sprinkler system is often provided to control a full scale fire if it develops. Clean agent fire suppression gaseous systems are sometimes installed to supress a fire earlier than the fire sprinkler system. Passive fire protection elements include the installation of fire walls around the space, so a fire can be restricted to a portion of the facility for a limited time in the event of the failure of the active fire protection systems, or if they are not installed.

19-inch racks for data equipment and servers, 23-inch racks for telecom equipment.
Cabinets and cages for physical access control over tenants' equipment.
Overhead cable rack (tray) and fiberguide, power cables usually on separate rack from data.
Air conditioning is used to control the temperature and humidity in the space. ASHRAE recommends a temperature range of 20–25 °C and humidity range of 40–60% as optimal for electronic equipmemt conditions.[citation needed] The electrical power used by the electronic equipment is converted to heat, which is rejected to the ambient air in the data center space. Unless the heat is removed, the ambient temperature will rise, resulting in electronic equipment malfunction. By controlling the space air temperature, the server components at the board level are kept within the manufacturer's specified temperature/humidity range. Air conditioning systems help control space humidity within acceptable parameters by cooling the return space air below the dew point. Too much humidity and water may begin to condense on internal components. In case of a dry atmosphere, ancillary humidification systems may add water vapor to the space if the space humidy is too low, which can result in static electricity discharge problems which may damage components.
Low-impedance electrical ground.
Few, if any, windows.

Physical security
Most colocation centres have high levels of physical security, and may be guarded continuously. They may employ closed-circuit television camera.
Some colocation facilities require that employees escort customers, especially if there are not individual locked cages/cabinets for each customer. In other facilities, a card access system may allow customers access into the building, and individual cages/cabinets have locks.

Power
Colocation facilities generally have generators that start automatically when utility power fails, usually running on diesel fuel. These generators may have varying levels of redundancy, depending on how the facility is built.

Generators do not start instantaneously, so colocation facilities usually have battery backup systems. In many facilities, the operator of the facility provides large inverters to provide AC power from the batteries. In other cases, the customers may install smaller UPSes in their racks.
Some customers choose to use equipment that is powered directly by 48VDC (nominal) battery banks. This may provide better energy efficiency, and may reduce the number of parts that can fail.

An alternative to batteries is a motor generator connected to a flywheel and diesel engine.
Many colocation facilities can provide A and B power feeds to customer equipment, and high end servers and telecommunications equipment often can have two power supplies installed.
Colocation facilities are sometimes connected to multiple sections of the utility power grid for additional reliability.

Cooling
The operator of a colocation facility generally provides air conditioning for the computer and telecommunications equipment in the building. The cooling system generally includes some degree of redundancy
In older facilities, the cooling system capacity often limits the amount of equipment that can operate in the building, more so than the available square footage.

Internal connections
Colocation facility owners have differing rules regarding cross connects between their customers. These rules may allow customers to run such connections at no charge, or allow customers to order such connections for a significant monthly fee. They may allow customers to order cross connects to carriers, but not to other customers.
Some colocation centres feature a "meet-me-room" where the different carriers housed in the centre can efficiently exchange data.

Most peering points sit in colocation centres.
Because of the high concentration of servers inside larger colocation centres, most carriers will be interested in bringing direct connections to such buildings.
In many cases there will be a larger Internet Exchange hosted inside a colocation centre, where customers can connect for peering.

External connections
Colocation facilities generally have multiple locations for fiber optic cables to enter the building, to provide redundancy so that communications can continue if one bundle of cables is damaged.

External links
Colocation at the Open Directory Project
A Los Angeles 'Hotel' for Internet Carriers 19 February 2007 NPR story
Source: http://en.wikipedia.org/wiki/Colocation_centre
Webhosting India

Dedicated hosting service

A dedicated hosting service, dedicated server, or managed hosting service is a type of Internet hosting where the client leases an entire server not shared with anyone. This is more flexible than shared hosting, as organizations have full control over the server(s), including choice of operating system, hardware, etc. Server administration can usually be provided by the hosting company as an add-on service. In some cases a dedicated server can offer less overhead and a larger return on investment. Dedicated servers are most often housed in data centers, similar to colocation facilities, providing redundant power sources and HVAC systems. In contrast to colocation, the server hardware is owned by the provider and in some cases they will provide support for your operating system or applications.

Operating system support

Availability, price and employee familiarity often determines which operating systems are offered on dedicated servers. Variations of Linux (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 up2date. 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 the operating systems above 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 & 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 (bps). For example, visitors to your server, web site, or applications utilize bandwidth as the traffic moves from your server to the Internet and vice versa. Connectivity refers to the “access providers” that supply bandwidth, or data transfer rate, through various connection points across a network or footprint to one or multiple data centers where dedicated servers are housed.

Bandwidth measurements are defined (per telecom standards) as the following:
First – 95th (measured using average bits and speed of transfer)
Second – Unmetered (measured in speed or bits)
Third – Total Transfer (measured in bytes transferred)

95th Method: Line Speed, billed on the 95th percentile, average or peak usage, refers to the speed in which data flows from the server or device. The measurement can be compared to mph (Miles Per Hour), or how fast something travels. Line Speed is measured using bits per second, kilobits per second, megabits per second, and 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, the measurement of actual data leaving and coming from the server, measured in bytes. Measurement between providers varies and includes one of the following equations:
Method 1: IN TRAFFIC + OUT TRAFFIC = TOTAL TRANSFER
Method 2: IN TRAFFIC = TOTAL TRANSFER
Method 3: OUT TRAFFIC = TOTAL TRANSFER

One of the reasons people choose 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 mostly likely 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

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
Simple Network Management Protocol hardware monitoring
Application monitoring
Technical support
Firewall services
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

Dedicated hosting server providers define their level of management based on the services they provide. In comparison, fully managed could equal self managed from provider to provider.
Administrative maintenance of the operating system, often including upgrades, security patches, and sometimes even daemon updates are included. Differing levels of management may include adding users, domains, daemon configuration, or even custom programming.

Dedicated server hosting providers may provide the following types of server managed support:

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.

Note: The provider will continue to maintain security on the network regardless of support level.

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, eggdrops 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.

Adult content is disallowed by many providers as it may either be of questionable legality or consume large amounts of bandwidth.
Spam is usually prohibited by the provider's Acceptable Use Policy.

Extra features
Useful features for dedicated servers may be included, or cost additional monthly fees:
Serial Console or KVM/IP - this is used to gain access to a server if for some reason the user is unable to get in via normal means (e.g. ssh), and permits a server to be recovered from boot-time configuration faults, such as filesystem recovery.
Automated restore of OS - an automated system can be used to restore the server to its original configuration.
Remote Backup Space - ssh/FTP space to backup data stored on the server.
ColdFusion (MX) - ColdFusion is the rapid server scripting environment for creating Rich Internet Applications.
SQL Server - Server dedicated to hosting Microsoft SQL databases and typically incur additional hosting fees.
Oracle - Server dedicated to hosting Oracle databases and typically incur additional hosting fees.

External links
Website hosting services at the Open Directory Project

Source: http://en.wikipedia.org/wiki/Dedicated_hosting_service

India Web Hosting

Virtual private server

Virtual private server (VPS, also referred to as Virtual Dedicated Server or VDS) is a method of partitioning a physical server computer into multiple servers such that each has the appearance and capabilities of running on its own dedicated machine. Each virtual server can run its own full-fledged operating system, and each server can be independently rebooted.
The practice of partitioning a single server so that it appears as multiple servers has long been common practice in mainframe computers, but has seen a resurgence lately with the development of virtualization software and technologies for other architectures.

Overview

The physical server boots normally. It then runs a program that boots each virtual server within a virtualization environment (similar to an emulator). The virtual servers have no direct access to hardware and are usually booted from a disk image.

There are two kinds of virtualizations: software based and hardware based. In a software based virtualization environment, the virtual machines share the same kernel and actually require the main node's resources. This kind of virtualization normally has many benefits in a web hosting environment because of quota incrementing and decrementing in real time with no need to restart the node. The main examples are Virtuozzo, HyperVM, Vserver, and OpenVZ which is the core kernel of both Virtuozzo and HyperVM.

In a hardware based virtualization, the virtualization mechanism partitions the real hardware resources. In typical implementations, no burst and/or realtime quota modification is possible; the limits are hard and can only be modified by restarting a virtual machine instance[citation needed]. This kind of environment is potentially more secure in the sense that it is less subject to "Quality of Service crosstalk" between VM instances; on the other hand, its security is typically dependent on the correctness of a larger and more complicated Trusted Computing Base[citation needed]. It is more commonly used in enterprise/commercial deployments[citation needed]. Examples include Microsoft Virtual Server, VMware ESX Server, and Xen.

Uses
Virtual private servers bridge the gap between shared web hosting services and dedicated hosting services, giving independence from other customers of the VPS service in software terms but at less cost than a physical dedicated server. As a VPS runs its own copy of its operating system, customers have superuser-level access to that operating system instance, and can install almost any software that runs on the OS. Certain software does not run well in a virtualized environment, including firewalls, anti-virus clients, and indeed virtualizers themselves; some VPS providers place further restrictions, but they are generally lax compared to those in shared hosting environments. Due to the number of virtualization clients typically run on a single machine, a VPS generally has limited processor time, RAM, and disk space.

Due to their isolated nature, VPSes have become common sandboxes for possibly-insecure public services or update testing. For example, a single physical server might have two virtual private servers running: one hosting the production-level (live) website, and a second which houses a copy of it. When updates to crucial parts of software need to be made, they can be tested in the second VPS, allowing for detailed testing to be conducted without requiring several physical servers.

Virtual private servers are also sometimes employed as honeypots, allowing a machine to deliberately run software with known security flaws without endangering the rest of the server. Multiple honeypots can be quickly set up via VPSes in this fashion.

Virtual private server hosting
A growing number of companies offer virtual private server hosting, or virtual dedicated server hosting as an extension for Web hosting services. Some web hosting companies call a Virtual Private Server a Virtual Dedicated Server/Dynamic Dedicated Server or the other way around.

Managed Hosting
Tools are provided to monitor and control the virtual machine.

Unmanaged Hosting
Typically only minimal services are provided, such as ssh console and reboot. Unmanaged VPS hosting is generally less expensive than managed VPS hosting.

Unmetered Hosting
Similar to unmanaged hosting but a fixed bitrate is offered so that it is not possibile to exceed a monthly budget.

Virtualization software
For some of the software packages commonly used to provide virtualization, see comparison of virtual machines.

See also
Emulation
Operating system-level virtualization
Paravirtualization
Virtual machine

Shared web hosting service

A shared web hosting service or virtual hosting service or derive host refers to a web hosting service where many websites reside on one web server connected to the Internet. Each site "sits" on its own partition, or section/place on the server to keep it separate from other sites.This is generally the most economical option for hosting as many people share the overall cost of server maintenance.

Description

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. In general shared hosting will be inappropriate for users who require extensive software development outside what the hosting provider supports. But on the other hand, shared hosting is cheaper than other types of hosting such as dedicated server hosting.
Shared hosting typically uses a web-based control panel system, such as cPanel, DirectAdmin, Plesk, InterWorx, Helm, H-sphere, Ensim, Sphera or one of many other control panel products. Most of the large hosting companies use their own custom developed control panel. Control panels and web interfaces have been causing some controversy lately as Web.com claims that it holds patent rights to the hosting technology with its 19 patents. Hostopia, a large wholesale host, recently purchased the rights to use that technology from web.com for 10% of retail revenues.[2] Web.com recently sued abtinfo.net as well for similar patent infringement.[3]
In shared hosting, the provider is generally responsible for managing servers, installing server software, security updates, technical support, and other aspects of the service. Most servers are based on the Linux operating system and LAMP (software bundle), which is driven by the low cost of open source software. 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, and typically greater security and stability under Linux).
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 (PPC) advertising 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.

Implementation

Shared web hosting can be accomplished in two ways: name-based and IP-based, although some control panels allow a mix of name-based and IP-based on the one server.

Name-based
In name-based virtual hosting, also called shared IP hosting, the virtual hosts serve multiple hostnames on a single machine with a single IP address.
When a web browser requests a resource from a web server using HTTP/1.1 it includes the requested hostname as part of the request. The server uses this information to determine which web site to show the user.

IP-based
In IP-based virtual hosting, also called dedicated IP hosting, each virtual host has a different IP address. The web server is configured with multiple physical network interfaces, or virtual network interfaces on the same physical interface. The web server software uses the IP address the client connects to in order to determine which web site to show the user. The primary reason for a site to use a dedicated IP is to be able to use its own SSL certificate rather than a shared certificate.

There are different types of IP Addresses based on the class system. For example, the default system is D Class domains. This means that the fourth segment of the IP Address changes. This is the case with domains bought from a company such as Ultimate Web Hosting. However, there are other options such as C Class where only the third segment changes etc.

Disadvantages
Name-based virtual hosts have some disadvantages:
They do not properly support secure websites (HTTPS). All name-based virtual hosts using the same IP address must share the same digital certificate. This is because the SSL/TLS handshake takes place before the hostname is sent to the server. Thus the server doesn't know which encryption key to use when the connection is made. An extension to the TLS protocol, part of RFC 3546 - Transport Layer Security (TLS) Extensions, specifies a way for the client to provide the requested host name as part of the handshake, but it is not yet widely implemented. Some of the shared hosting providers require their customers to get Unique IP in order to properly set up HTTPS.

If the Domain Name System is malfunctioning, it is harder to use a name-based virtually-hosted website. Ordinarily, in this case, the user could fall back to using the IP address to contact the system, as in http://127.0.0.1/ (invalid IP for example only). However, the web browser doesn't know what hostname to send to the server, but a name-based virtual host requires it. In this case, the default web host is sent back to the browser for that IP address. Therefore most hosters offer an alternative access method like http://127.0.0.1/~virtualhostname to provide access in such cases.

They will not work with browsers that do not send the hostname as part of requests. This is true for older HTTP/1.0 browsers that have not retrofitted the host field feature from the HTTP/1.1 protocol. (The "Host" header that distinguishes between various DNS names sharing a single IP address was optional in HTTP/1.0; it is mandatory in HTTP/1.1, issued in 1999 as RFC 2616.) Since nearly every webbrowser that is currently used supports the HTTP/1.1 protocol and thus also virtual hosting, this is not a real issue.

References
^ Glossary of Terms. wilshirepr.com. Retrieved on 2007-10-05.
^ Yahoo! Finance: Hostopia Licenses Web.com's Patents
^ The Street: Go Daddy Gets Sued

See also
Hosting
Web hosting service
Dedicated hosting service
Web server
Source: http://en.wikipedia.org/wiki/Shared_web_hosting_service

Free web hosting service

A free web hosting service is a web hosting service that is free, usually advertisement-supported and of limited functionality, though not at all times. Free web hosts will usually provide a subdomain (yoursite.example.com) or a directory (www.example.com/~yourname). In contrast, paid web hosts will usually provide a second-level domain along with the hosting (www.yourname.com). Many free hosts do allow use of separately-purchased domains. Rarely, a free host may also operate as a domain name registrar.

Features and limitations

Only a few free web hosts offer basic package for free 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
Disabling on hotlinking of files
File type restrictions (for example MP3, MPEG, ZIP etc.)
Compulsory placement of the Webhosts' Banner or Popup ads into all web pages
No provided uptime guarantee
No allowance of custom URLS, such as "http://www.domain.com". It has to be "http://www.provider.com/domain" or "http://domain.provider.com/".

Some free host may provide these extra features:

A web based control panel
Free email accounts for the domain or subdomain hosted
File transfer via FTP
Scripting languages: PHP, ASP, Perl etc.
Relational databases such as MySQL
Scheduled processes, known as cronjobs
Other features such as guestbooks
Forums and community resources not typical of paid hosts
Reward systems which provide extra free products and services
Have no data limitations offering unlimited space

Monetizing free webhosting

The majority of the hosting companies use free hosting to introduce their services, and as an entry point to their more expensive offerings. Generally they recoup their costs in one of two ways:

Advertising - Selling online advertising on the customer sites is generally considered a fair trade - the reasoning is that high traffic sites are more expensive to host, but the additional traffic allows for additional ad impressions therefore covering the cost. For the web master, it can be a good trade if the advertising is of good quality and non-competitive. This is one of the main reasons that businesses do not use free hosting for their website. The majority of free hosting companies use this method.

Referrals - Using a simple form of viral marketing, these providers rely on the users to spread the offer. The ratio of free to paid accounts is known, and by having each free user refer a number of friends, the hosting provider is able to get enough paid accounts to cover the cost.
Resell Hosting - This is where someone starts up a hosting company, attracts lots of visitors, then sells the hosting company to someone else once it can no longer support itself. Once sold, this individual uses the money to start up multiple hosting ventures and sells each in turn.
Some hosting companies are using hybrid approaches that mix both tactics.

Methods of giving out web hosting

A few methods of giving out Free Webhosting to people by Webhosts

Instant activation
Hosts with instant activation usually give very little storage space and bandwidth allowance, and have lots of limitations. The webhosts usually either require the users' web pages to display their banner ads, textlink ads, or popups; or else the users' files to be uploaded through a web-based file manager that display ads to the user uploading files.
Hosts with instant activation are often abused by spammers, which upload pages to these hosts to use for link spamming

Approved activation
Hosts with approved activation offer good space and Bandwidth but low on features. Approved applications are processed by administrators hired by the free hosting company who validate the applications depending on the details provided by the users. The main objective behind manual approval is to prevent spam and phishing websites.
Activation time can be as low as few minutes or as long as a week. Different hosts have different policies for Approval and Activation.

Post for hosting
Some free hosts require posting in a forum. Forum-based free hosting requires users to either reach a certain amount of posts before getting a free hosting account, or be an active contributor in the forum. Forum-based free hosting often work on a system of points where posts give points to a user and can be used as credits toward getting a hosting account or more resources. Typically, the forum where users have to post contain advertising as the hosts way of making a profit.

A typical example of this system would be to post to gain "credits" (points). Perhaps every credit is equivalent to 24 hours or a day. So, if you make a post and get 7 credits, your hosting account would be active for 7 days. While some hosts allow these credits to be distributed, others do not. However, when they are allowed to be distributed, they might be used as a currency in exchange for services.

Forum applications
This method is popular, as the hosts can decide which applications to deny and allow. This is common when a popular forum has free hosting as an add-on service, rather than the other way around.

File hosting on webhosts

Most free web hosts discourage using their services for file or image hosting only, with no web page, since advertising is displayed on the web page. Because of this, hotlinking is usually disallowed on free hosts. Some free webhosts will also disallow files over a certain size (for example, 5 MB). However, there are free file hosting services which allow large files as well as hotlinking.

Co-branding and resellers
Some services offer co-branding services. These let you brand fixed plans with your own company. Other services, offer WHM or panel reselling. This allows the client to develop his or her own web hosting plans and business.
Source: http://en.wikipedia.org/wiki/Free_web_hosting_service

Web Hosting

A web hosting service is a type of Internet hosting service that allows individuals and organizations to provide their own website accessible via the World Wide Web. Web hosts are companies that provide space on a server they own for use by their clients as well as providing Internet connectivity, typically in a data center. Web hosts can also provide data center space and connectivity to the Internet for servers they do not own to be located in their data center, called colocation.

Service scope

The scope of hosting services varies widely. The most basic is web page 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 free to their subscribers. People can also obtain Web page hosting from other, alternative service providers. Personal web site hosting is typically free, advertisement-sponsored, or cheap. Business web site hosting often has a higher expense.
Single 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, Ruby on Rails, 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 highly recommended.

The host may also provide an interface or control panel for managing the Web server and installing scripts as well as other services like e-mail. 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, searchable directories can be used. One must be extremely careful when searching for a new company because many of the people promoting service providers are actually affiliates and the reviews are biased.

Hosting reliability and uptime

Hosting uptime refers to the percentage of time the host is accessible via the internet. Many providers state that they aim for a 99.9% uptime, but there may be server restarts and planned (or unplanned) maintenance in any hosting environment.
A common 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 provider. Many providers tie uptime and accessibility into their own service level agreement (SLA). SLAs sometimes include refunds or reduced costs if performance goals are not met.

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 often 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. A shared website 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 provider. Resellers' accounts may vary tremendously in size: they may have their own virtual dedicated server to a colocated server.

Virtual Dedicated Server: dividing a server into virtual servers, where each user feels like they're on their own dedicated server, but they're actually sharing a server with many other users. The users may have root access to their own virtual space. This is also known as a virtual private server or VPS.

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. 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 box, which means the client is responsible for the security and maintenance of his own dedicated box.

Managed hosting service: the user gets his or her own Web server but is not allowed full control over it (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 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. 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.

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.

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 PC's.

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 hostname 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.

Some specific types of hosting provided by web host service providers:
File hosting service: hosts files, not web pages
Image hosting service
Video hosting service
Blog hosting service
One-click hosting
Shopping cart software

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. The webhosting 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 for its 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 doesn't have to worry about the more technical aspects. These Web Content Management systems are great for the average user, but for those who want more control over their website design, this feature can sometimes be a nuisance rather than a feature.

Macintosh has supported Apache since the "Tiger" system was introduced, and the Darwin (operating system) provides a Unix-like interface via Terminal.app. Such systems have complete Web hosting capabilities, including support for PHP, and Perl and Shell scripts. Personal Web Sharing can be activated in the Sharing panel of System Preferences....
One may also search the Internet to find active webhosting message boards and forums that may provide feedback on what type of webhosting company may suit his/her needs.

References
^ How to Activate Web Hosting on a Macintosh

Web Hosting India
See also
Overselling
Shared web hosting service
Dedicated hosting service
Source: http://en.wikipedia.org/wiki/Web_hosting