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When it comes to computer technology, there are several concepts that may be difficult to grasp. Do you know what is a server? Where they are used? Is the server hardware or software? In reality, what servers are and how they work are probably simpler than you’d expect.
What is a Server?
In network terminology, a server is a computer that serves many kinds of information to a user or client machine. Usually, a server does only a few things for a number of clients. The things that a server does is called a service. The computer that you use to access these services is called the client. A client-server relationship is a relationship between client and server.
Does a Server look like a normal computer?
Usually, servers are more powerful and reliable. They are usually more expensive than normal computers. Sometimes, servers can be clustered, which means many servers are working together to do one service. A commercial server isn’t like the kind of computer you might use to read this article.
For example, Wikipedia has web servers that have a service for sending web pages over the Internet. Your client computer talks to Wikipedia’s web page service to get web pages for you. A server doesn’t have a screen or keyboard.
A server can also host many other services such as internet games, share files, and give access to peripheral equipment such as printers.
In simple words, servers are powerful computers. Your computer stores files and data you’ve put in it. But a server contains all the data associated with the websites that are hosted by it. And it shares that information with all computers and mobile devices that access them.
What Does a Server Do?
- Servers can do everything a standard desktop computer can do and more. Vice-versa, computers can run server processes, but do so far less productively. Generally, servers offer the following features to the networks they serve:
- Scalability to serve a growing or fluctuating number of devices, users, and workloads
- High processing power with rising CPU and RAM specs to handle network workloads
- Reliability to ensure critical systems remain online and available
- Collaboration between personnel with access to shared network resources
- Cost savings over time because servers can reduce stress on network devices
How Does a Server Work?
To function as a server, a computer must be configured to listen to requests from clients on a network connection. This functionality can be provided by the operating system or as a separate application installed on the computer.
For example, Microsoft’s Windows Server operating system provides the functionality to listen to and respond to client requests. Additionally installed roles or services increase which kinds of client requests the server can respond to. In another example, an Apache webserver responds to Internet browser requests via an additional application, Apache, installed on top of an operating system.
When a client requires data or functionality from a server, it sends a request over the network. The server receives this request and responds with the appropriate information. This is the request and response model of client-server networking, also known as the call and response model.
A server will often perform numerous additional tasks as part of a single request and response, including verifying the identity of the requestor, ensuring that the client has permission to access the data or resources requested, and properly formatting or returning the required response in an expected way.
On the most basic level, when you type in a URL in your Internet browser (like Chrome, Safari, or Explorer), your computer communicates with the server hosting that website to get the data to pull the site up on your computer.
Types of Servers
There are many types of servers that all perform different functions. A website may be served by one or more of the common server types:
1. File Server
File servers store and distribute files. Multiple clients or users may share files stored on a server. Along with the facility of centrally storing the files, it offers easier backup or fault tolerance solutions. File server hardware can be designed to maximize read and write speeds to improve performance.
2. Print Server
Print servers allow for the management and distribution of printing functionality. Rather than attaching a printer to every workstation, a single print server can respond to printing requests from numerous clients. Today, some larger and higher-end printers come with their own built-in print server, which removes the need for an additional computer-based print server.
3. Application Server
Application servers run applications instead of client computers running applications locally. Application servers often run resource-intensive applications that are shared by a large number of users. Doing so removes the need for each client to have sufficient resources to run the applications. It also removes the need to install and maintain software on many machines as opposed to only one.
4. DNS Server
Domain Name System (DNS) servers are types of application servers that provide name resolution to client computers by converting names easily understood by humans into machine-readable IP addresses. When a client needs the address of a system, it sends a DNS request with the name of the desired resource to a DNS server. The DNS server responds with the necessary IP address from its table of names.
5. Mail Server
Mail servers are a very common type of application server. Mail servers receive emails sent to a user and store them until requested by a client on behalf of said user. Having an email server allows for a single machine to be properly configured and attached to the network at all times. It is then ready to send and receive messages rather than requiring every client machine to have its own email subsystem continuously running.
6. Web Server
One of the most abundant types of servers in today’s market is a web server. A web server is a special kind of application server that hosts programs and data requested by users across the Internet or an intranet. Web servers respond to requests from browsers running on client computers for web pages, or other web-based services. Common web servers include Apache web servers, Microsoft Internet Information Services (IIS) servers, and Nginx servers.
7. Database Server
Database servers are high-powered computers that store and manage data stored on a server for a network of users and devices. The terms database servers, database management systems (DBMS), and relational DBMS (RDBMS) get used interchangeably, but RDMBS is the most often implemented type of database management. Collectively, database server solutions offer central data management, security, controls for access and permissions, and an interactive repository for a network of users.
8. FTP Server
FTP servers, or “File Transfer Protocol” servers, have a single purpose: to host a file exchange among users.
These servers do not provide any type of encryption by default, so there are a number of secured versions of the protocol that are often used in its place (such as sFTP which is FTP over secure SSH protocol).
This type of server allows users to upload files to it or download files after authenticating through an FTP client. Users can also browse the server’s files and download individual files as they wish.
Can My Computer Be A Server?
Any computer, even a home desktop or laptop computer, can act as a server with the right software. For example, you could install an FTP server program on your computer to share files between other users on your network. Although it is possible to have your home computer act as a server, keep the following ideas in mind.
- Your computer and the related server software must always be running to be accessible.
- When your computer is used as a server, its resources (e.g., processing and bandwidth) are taken away from what you have available to do other things.
- Connecting a computer to a network and the Internet can open up your computer to new types of attacks.
- If the service you’re providing becomes popular, a typical computer may not have the necessary resources to handle all of the requests.
Conclusion: Since uptime is critically important for most servers, servers aren’t designed to shut down but instead run 24/7. However, servers sometimes go down intentionally for scheduled maintenance, which is why some websites and services notify users of scheduled downtime or scheduled maintenance.