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2009-09-06T07:05:00.000-07:00

:: Bandwidth and connectivity ::

2009-09-04T19:53:00.000-07:00

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 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. 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, the measurement of actual data leaving and arriving, measured in bytes. Measurement between providers varies, though it is either the total traffic in, the total traffic out, whichever is the greater or the sum of the two.

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.

:: Operating system support ::

2009-09-04T19:49:00.000-07:00

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 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.

:: Obtaining hosting ::

2009-09-04T19:46:00.000-07:00

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 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 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 may not be adequate.

Most modern desktop operating systems (Windows, Linux, Mac OS X) are also capable of running web server software, and thus can be used to host basic websites.

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. However some of these message boards and forums will require not only registration, but a paid subscription to be able to access the sections and sub forums with such information.

:: Types of hosting ::

2009-09-04T19:39:00.000-07:00

Types of hosting

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

Hosting services limited to the Web:

Many large companies who are not internet service providers also need a computer permanently connected to the web so they can send email, files, etc. to other sites. They may also use the computer as a website host so they can provide details of their goods and services to anyone interested. Additionally these people may decide to place online orders.

Free web hosting service: Free web hosting is offered by different companies with limited services, 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. The features available with this type of service can be quite extensive. 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 collocated 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 for short) 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. This is also known as a virtual private server or VPS. 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 (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.
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. Removing
single-point of failures and allowing customers to pay for only what they use versus what they could use.
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.
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 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.

:: Hosting reliability and uptime ::

2009-09-04T19:27:00.000-07:00

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 at least 99.9% uptime (roughly equivalent to 45 minutes of downtime a month, or less), but there may be server restarts and planned (or unplanned) maintenance in any hosting environment, which may or may not be considered part of the official uptime promise.

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.

:: Service scope ::

2009-09-04T19:09:00.000-07:00

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, ColdFusion, 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.