Building a website is just the first part of establishing an Internet presence; installing that website on a server connected to the Internet — a “web server” — is how users will actually see the site you've created.
A “web hosting provider,” like ServInt, is a company that owns, operates and rents (or sells) these web servers, and offers the high-speed connections necessary to quickly deliver website content to end users.
The equipment is housed in a data center, which features sophisticated environmental control and monitoring systems, fire-suppression capability, and security systems to prevent unauthorized physical and electronic intrusion.
Hosting providers maintain their web servers, adding new hardware and software as needed, monitoring the systems to ensure maximum uptime, installing security patches, and providing customers with help and support. Most of the differences between hosting providers can be found in these areas of responsibility. Cheaper web hosts usually find the money to offset their lower monthly fees by reducing their investment in maintenance and customer support — whereas “enterprise-grade” hosts like ServInt spend more time and money making sure their customers' sites are always up and running.
Nearly every server sold today is some form of virtualized server, existing on a larger physical host machine (or spread across a cluster of machines).
While it is still possible to buy a non-virtualized, stand-alone physical server, such as our SMD line, the scalability, power and ease of virtualized servers has completely taken over the market.
In the universe of server virtualization, there are four main forms of technology:
In a shared hosting environment, multiple websites on the same server share the same hardware, connectivity resources and some software. For small or very simple websites, this can be an acceptable hosting solution, but performance and security are often major issues.
Because some sites on the server may require large amounts of memory and bandwidth, the efficient performance and delivery of other sites on that server can be negatively affected. Certain applications that can be modified by one user may affect all others, and there is a risk of data being compromised (usually unintentionally) by other users.
For these reasons, ServInt does not offer its customers shared hosting environments.
Virtual Private Servers (VPS) afford customers more control over their hardware resources, software and access than shared servers.
With a VPS solution, multiple customers are housed on the same server, but each client has a “private” area on the server to which critical resources are assigned — so the performance of one customer's site does not impact the performance of other sites in a different partition. Also, the number of private areas on each server is limited, ensuring that resources are not over-leveraged.
Finally, VPS hosting solutions are often "managed" services, an important point to remember when selecting a VPS provider. Managed services means the web host is responsible for configuring everything installed and delivered with a new account, and for repairing any problems with any pre-configured system. Managed hosts also typically handle a number of other technical issues, such as installing patches for the operating system, as well as supporting certain key third-party software.
What is commonly referred to as cloud is actually made up of three similar, yet unique hosting solutions:
- Software as a Service (SaaS)
- Platform as a Service (PaaS)
- Infrastructure as a Service (IaaS)
Software as a Service
When a customer purchases cloud SaaS, they are simply purchasing access to an application, or software, running on someone else's hardware, on some unknown bank of servers. Their experience is divorced from anything beneath the software they are accessing. Wordpress installations running on wordpress.org are a great example of this. Customers load their content onto Wordpress's site and their blog is live. They neither know nor care what type of hardware or operating system Wordpress is using on their back end.
Platform as a Service
Cloud PaaS products are one level deeper than SaaS. In PaaS, the Platform — or programming language environment — is offered to the customer, not simply a piece of Software. ServInt's Java cloud product, Jelastic, is a good example of a PaaS. Jelastic is an elastic Java environment where developers create programs and operations in this programing language. Each Java "instance" grows and contracts dynamically based on load. And while the customer specifies what level server resources they wish to commit (RAM, CPU, disk space, etc.), all customer accounts exist in the ServInt Jelastic cloud, a network of computers that share the entire Jelastic workload.
Infrastructure as a Service
The final step in cloud services is IaaS, in which the Infrastructure itself is offered as the service. Cloud IaaS products are virtual servers, not unlike the virtualization system ServInt uses for VPS. This similarity is one of the reasons why some hosting service providers choose to market VPS-based hosting services as "cloud." There are differences, however. For one thing, cloud IaaS virtualization is typically a hypervisor-based technology, which gives each user kernel access, choice of OS, and much more.
Like cloud SaaS and PaaS, cloud IaaS also divorces the user instance from any one piece of hardware. The "Cloud" in cloud hosting is a suite of hardware that is controlled by a centralized software management layer. This gives each cloud the ability to grow as needed simply by having technicians add hardware. For users, however, there are budgetary and performance trade-offs to consider.
The challenge with cloud hosting is that it is far more complex to code for and configure than VPS or dedicated hosting. While a single VPS server might house a database, run a web server, an email server and a name server, a single cloud instance is often designed to do one thing at a time and scale that single function on demand.
While it's true that a single cloud instance can run more than one application, doing so would cause the user to lose the benefit of easy instance scaling. Cloud customers fall into two main types: those who have many instances running at any given time, each performing one specific function and each being billed individually, and those who run cloud instances like mini VPSes, paying a premium for a complexity they are not using.
To avoid cost overruns, many businesses with large hosting requirements build their own "private" clouds in which they control all the hardware housing their cloud instances. Doing so gives them the ability to support all their business hosting and storage needs on multiple instances they set up and tear down at will, on a secure platform of their own design that they control. Since they manage their own dedicated hardware and pay for the sole use of it, they pay for their server on a simple monthly basis, rather than tracking and managing the hourly use of multiple, app-specific instances.
Private clouds are perfect for customers that need the ability to steadily and flexibly add resources, and who do not have massively dynamic workloads requiring unpredictable spin-up and tear-down of temporary instances. Typically, these are the requirements of larger business hosting customers.
A more affordable alternative to a private cloud is a dedicated physical server running a virtualization layer. These products offer the scalability and flexibility of virtualization, with the safety, stability and predictable billing of a stand-alone host machine.
Running a virtualization layer over dedicated hardware allows the customer to easily migrate between host machines in order to scale up and down (and even back into a fully virtualized product if need be).
Some of today's virtualization systems are powerful enough to provide all the scalability benefits of hypervisor-based cloud IaaS systems without sacrificing the platform stability of VPS or dedicated servers. Our Flex Private line of servers, for example, uses such a system — a proprietary combination of Parallels' Virtuozzo and our own SimpleScale™ technologies — to provide high levels of redundancy, quick image restoration, and free nightly backups. In addition, however, Flex technology allows near-instant scaling and control of key parameters including RAM and disk space.
Need help understanding which technology is right for your application? Talk to one of our hosting specialists today.