Server

A server is a system that provides resources, data, services, or programs to other computers, known as clients, over a network. In theory, servers are those computers that share resources with client machines. There are many types of servers, such as web servers, mail servers, and virtual servers.

An individual system can, at the same time, provide resources and use those of another system. It means that every device could be both a server and a client.

The first servers were mainframes or microcomputers, which are so named because they are much smaller than mainframe computers. However, as technology progressed, they ended up outgrowing desktop computers, making the term microcomputer somewhat inappropriate.

Initially, these servers were connected to clients that did not perform any natural computing, and they were known as terminals. These terminals existed to accept inputs through a keyboard or card reader and return the results of any calculation to a screen or printer. The actual computing was done on the server.

Later, servers became high-powered individual systems connected to a set of less powerful client computers over a network. This network architecture is familiar as the client-server model, in which both the client computer and the server have computational power. But specific tasks are delegated to the servers. In previous computer models, such as the mainframe-terminal model, the first one did act as a server with all the laws, although that name did not mention it.

Definition Server

The definition of the server concept has evolved with the advancement of technology. Today, a server may be nothing more than software that runs on one or more physical computing devices. We often refer such servers as virtual. Originally, virtual servers were used to increase the number of features an individual hardware server could perform. Currently, virtual servers are usually run in the cloud, within hardware that belongs to a third party and accessed through the internet.

A server can design to perform a single task, such as a mail server. That accepts and stores email messages and then delivers them to a requesting client. Servers can also complete more than one task. Such as a file and print server that stores files and accepts print jobs from clients, then sends them to a network-connected printer.

For a device to work as a server, it must configure to listen for clients’ requests in a network environment. This functionality can exist as part of the operating system: in the form of an installed application, a role, or a combination of both.

For example, Microsoft’s Windows Server operating system provides the necessary features to listen to and respond to client requests. Also, installed roles or services increase the number of client requests that the server can respond to. In another example, an Apache webserver responds to requests from the client’s internet browser through an additional application, Apache, installed at the top layer of the operating system.

When a client requests data or functionality from a server, it does so by sending a request over the network. The server receives this request and responds with the corresponding information. It is the client-server connection request and response model, also known as the call and response model.

Types

Often a server will perform numerous additional tasks as part of a single request and response. Such as verifying the requestor’s identity, ensuring that the client has permission to access the requested data or resources. And correctly formatting or returning the required response from the expected form.

Many types of servers perform different functions. In most networks, we can find at least one of the most common types of servers:

File Servers

File servers store and distribute files that multiple clients or users can share. Also, centralized file storage offers backup or fault-tolerance solutions easier than providing file security and integrity on each device in your organization. File server hardware can design to boost read and write speeds to improve performance.

Print Servers

Print servers allow the management and distribution of the functionality of printing documents. To avoid having to connect a printer to each workstation. We can have a single print server to respond to many clients’ print requests. Today some large, high-end printers come with their built-in print server, saving the need to install one on a separate computer. This internal print server makes the printer respond to print requests from connected clients as well.

Application Servers

We use these servers to run applications remotely rather than having client computers do it locally. Application servers often run resource-intensive software and share it with a large number of users. On the one hand, we only have to install and maintain the software on a single machine, and we avoid the need for each client to have sufficient resources locally.

DNS Servers

Domain Name System (DNS) servers are application servers that provide name resolution capabilities to client computers. Name resolution is about converting human-readable names to machine-readable IP addresses. The DNS system is a widely distributed database of words and other DNS servers that can be queried for an unknown computer name. When a client needs a system’s address, it sends a request for the desired resource name to a DNS server. Which responded with the corresponding IP address from its name table.

Mail Servers

Mail servers are a prevalent type of application server. These servers receive email messages that we forward to a user and store them until a client requests them on behalf of that user. Having an email server allows us to have a single machine correctly configured and connected to the network at all times. Ready to send and receive messages instead of waiting for each client to have their email subsystem running continuously.

Web servers

One of the most abundant types of servers on the market today is web servers. A web server is a type of application server that hosts programs and data requested by users over the internet or on an intranet. Web servers respond to requests for web pages or other web-based services that arrive from browsers running on client computers. Among the web servers that we can find most frequently. We have Apache servers, Microsoft Internet Information Services (IIS), and Nginx.