In simple terms, a web server is a computer that listens to and responds to visitor requests and makes your website functional. Large web hosting providers have hundreds of web servers to host customer accounts. Each web server is capable of hosting a theoretically unlimited number of websites. The resources of the server like the CPU, memory, storage and network bandwidth are shared by all the websites on that server. As each website takes up a portion of the server’s resources, the performance of all the websites on the server decreases as the number of websites hosted on the server increases. Hence, there is a practical limit on the number of websites that can be hosted on a single server without compromising performance.
For small websites with very low resource usage, it is not necessary, cost effective or practical to put each website on a separate server. Hence, web hosting companies put the websites of several customers on a single server and all those websites share the resources of that server. This is called shared web hosting. Shared hosting is a good option if you are hosting websites with low to moderate traffic.
Advantages:
- It is cheap and efficient: It provides efficient and cheap hosting to a large number of customers without compromising performance. As a result, shared hosting is the most popular method of web hosting.
- It is fully managed: A web server has to be configured, requires hardware and software upgrades and periodic security patches. This is a technical job, which can be difficult for the average customer. In shared hosting, the servers are fully managed by the hosting company. You can host a website easily without any technical knowledge.
Disadvantages:
- Lower assurance of resource availability or performance: Shared hosting works well when all the sites on the server are well behaved. Each website is expected to use resources fairly. There is no protection in place to prevent unfair use of resources. If one website overuses bandwidth, CPU or performs too many database queries, it will adversely affect the performance of all the websites sharing the same server. However, web hosting companies usually have automated and manual monitoring mechanisms to detect unfair usage. The common response is to shut down the offending website so that other websites on the server can work normally.
- Reduced security: As there are many websites running different types of software on the same server, web hosting sites on shared hosting are usually exposed to a larger number of security holes than other forms of web hosting.
- Limitations: Websites on shared hosting have to work within the limitations of the configuration provided by the web host. Limitations may exist on the type of software that can be installed, features that are available or on configuration options. This helps reduce the risk of security issues or resource overuse.
A VPS is the next logical upgrade from shared hosting. In a VPS environment, one server is partitioned by software between different customer accounts. Each partition is a mini server, which gets a fixed portion of the main server’s resources. Each account runs as a separate server with its own operating system and software.
You have the freedom to install the software you choose or configure your VPS according to your requirements. It is an excellent choice if you have high traffic websites or if you are hosting websites that have special software or configuration requirements. It is also suitable if you expect rapid growth in traffic or are running CPU intensive applications.
Advantages:
- Guaranteed availability of server resources. Virtual servers on a physical server don’t compete for resources and have no impact on each other.
- Freedom to select an operating system, install custom software and configure the server as required.
- A VPS can be shut down or rebooted without affecting the other virtual servers residing on the same server.
- Upgrades are possible and resources can be added if required.
- Better security.
Disadvantages:
- There is a limit beyond which upgrades may not be possible or make sense on a VPS.
- Choice of operating system is limited to the options provided by the hosting company.
- Technical knowledge is required because hosts usually expect customers to manage their servers. Many web hosts are also offering the option of managed VPS.
A dedicated server caters to only one customer account. Customers have full control over the server resources and software. They can choose any compatible operating system, install any software and have full freedom to configure their servers.
Dedicated hosting is ideal for you if you need more resources and freedom than what a VPS can provide. It is also perfect for websites with huge traffic, frequent database access and complex applications. Dedicated servers are also hired by small web hosting companies and resellers so that they can in turn provide shared or VPS hosting to their customers.
Advantages:
- All the advantages of a VPS.
- Ability to select from a variety of hardware options and resources and the ability to upgrade them if needed.
- Complete control over the OS, software and resources.
Disadvantages:
- Costs much more than a VPS.
- Technical knowledge is required if it is not a managed server.
In all types of conventional web hosting, websites are hosted on physical servers. The maximum resources that a website can use is limited to the resources available on the server on which it is hosted.
Conventional hosting has some disadvantages. If a server goes down or has to be shut down for an upgrade or maintenance, all the websites running on that server go down. When web sites grow or experience more traffic, they need more resources. There is a limit to the amount of resources that can be added to a server. Another problem is the inability of physical servers to handle major traffic spikes and the resultant spikes in the demand for resources. As a result, it becomes necessary to keep a lot of surplus resources on a physical server. Although these extra resources are not being used, they contribute to extra costs, which get passed on to customers. Cloud web hosting eliminates most of the shortcomings of physical servers.
A cloud is a cluster of physical servers. All the resources of the member servers are available to the cloud. The total resources in the cloud is the sum total of the resources of the servers contained in it. The entire cloud can act as one virtual cloud server or it can be partitioned into many virtual cloud servers. If the amount of resources in the cloud is huge, it is possible to create servers with much more computing power and resources than what is possible with physical servers.
Cloud servers have several advantages:
- Minimal downtime: As each cloud server is using the cloud’s resources rather than the resources of any one physical server, physical servers can be added and removed from the cloud on the fly. If one physical server shuts down, it does not result in any downtime on any website hosted on the cloud.
- Load balancing: Cloud servers can handle traffic spikes with relative ease. When there is a spike in the demand for resources, the increased load is distributed to multiple physical servers within the cloud. This cushioning effect helps the cloud instantly react to and mitigate server load.
- Instant scalability: As a cloud server can have a lot more resources than a physical server and resources can be easily added, cloud servers can be upgraded instantly with no downtime.
- Cost effectiveness: Cloud servers can be upgraded or downgraded on demand. Hence, customers pay only for the resources that they use. There is no need to pay for surplus capacity if it is not needed all the time. This is perfect for websites that experience seasonal increases in traffic.
Cloud web hosting is a scalable, efficient, cost effective and fault-tolerant technology. More and more web hosting providers are switching to this technology, especially for shared and VPS hosting. Some hosts are also offering dedicated servers using cloud computing technology.
