What Is a Server? Definition, Types, and Features
A server is a robust machine designed to process, store, and manage data, devices, and systems within an organization. This advanced computer system provides resources to networking units to deliver specific services, such as displaying web pages and sending or receiving emails, among others. Computer hardware, software, or even virtual machines with basic software capabilities can act as a server. However, server functionalities extend beyond a typical computer. They handle intricate server processes, from managing multiple client queries simultaneously, hosting content-heavy websites, and establishing a shareable drive for network devices, to handling intensive tasks, such as database transaction management that require high computing power. Servers respond to user requests through a client-server model. In this model, the host device that powers network devices is known as the host server, and the network devices that utilize the resources the host device provides are referred to as clients.
Key components of a server
Server machines consist of essential components capable of running code, sending or receiving data, and storing data for varying periods. While these components can also be found in laptops, smartphones, and IoT devices, they are significantly more robust in servers. Let’s delve into the four primary components of a server:
- Processor
The central processing unit (CPU), commonly known as the processor, serves as the primary component in every server, functioning as the server system’s brain. Modern server computers are now outfitted with robust processors featuring multiple cores, enabling them to carry out numerous instructions simultaneously. Leading processor brands in the market today comprise Intel Xeon processors, HPE, Dell, Huawei, and more.
- RAM
RAM, also known as random-access memory, is a crucial component in a computer system. It serves as the short-term memory unit responsible for storing working data and machine code. Processors heavily rely on RAM to efficiently read and write data at a faster pace. This is particularly important for servers that handle multiple instructions simultaneously. By retrieving data from RAM instead of hard drives, servers can significantly reduce the time required for data access. Additionally, when a processor executes a computer program, it typically resides in the main memory, which is RAM. Therefore, the performance of the RAM ultimately plays a vital role in determining the execution speed of a server computer.
- Storage
Servers employ storage components to contain a range of files necessary for executing machine code. These files consist of operating system files, libraries, databases, website data, application data, and other types of data. Traditional hard drives and solid-state drives (SSDs) are utilized on the server side for data storage. The choice of storage medium is based on the specific needs and requirements. For example, a database server should have the capability to read and write data more quickly than a file archive server, which does not need to access data as rapidly. It is essential to consider that the performance of a server can be negatively impacted by a single storage device. In the event of a storage component failure, all websites hosted by the web server may go offline, resulting in a subpar online user experience. This is why most servers utilize a Redundant Array of Independent Disks (RAID) to tackle such issues and improve fault tolerance. RAIDs are an array of independent disks that provide better storage performance and data redundancy than any single storage component.
- Bandwidth
Servers are responsible for handling user requests and distributing content through the internet or a combination of networks like WAN or LAN. Servers need to possess a greater bandwidth to efficiently serve numerous clients and promptly respond to queries.
How does a server work?
Upon entering a website URL in the web browser, a series of servers eagerly await to deliver the requested information. The initial step involves the web browser dissecting the URL into three distinct components.
- Protocol: The first part is the hypertext transfer protocol (HTTP or HTTPS), which acts as a communication pathway for servers and browsers to talk to each other.
- Server name: The second part of the URL relates to the server name. Here, a domain name server (DNS) translates the domain name into the server’s IP address that hosts the requested website.
- File name: The final part encapsulates files that include HTML, CSS, fonts, images, graphics, and many other ingredients that make up the requested website.
The first step involves the web browser sending a request for the domain name to the DNS server. Subsequently, the DNS server determines the IP address linked to the requested domain. Once the IP address is received, the browser forwards the user’s request to the target server. The server then gathers the website data, including the essential dynamic elements required to showcase the website on the user’s end, and sends it back as a response to the user’s query.
Types of Servers
Servers of different types exist today. Several servers can perform multiple jobs, such as hosting websites, sending and receiving emails, safeguarding internal networks, etc. On the other hand, dedicated servers such as database servers or print servers focus on one objective. Some of the key server types that are an integral part of networking environments are.
1. Web server: Web servers are designed to run websites and apps through client programs (web browsers) such as Internet Explorer, Chrome, Firefox, Opera, or Safari. They are responsible for storing, processing, and delivering web content to users. They support protocols such as HTTP, FTP, and SMTP that are key to information exchange between network devices. In a network, all machines hosting websites have web server software to better manage user access to hosted files. Some examples of web servers include Apache HTTP Server, Microsoft Internet Information Services (IIS), and Sun Microsystem’s Sun Java System Web Server.
2. Mail server: A mail server facilitates email storage and management for clients. It uses different protocols for sending and receiving emails. For example, the Simple Mail Transfer Protocol (SMTP) is used to send an email. The server relies on the Post Office Protocol (POP3)l to store and receive an email. Mail servers are similar to a typical post office that stores and sorts mail before sending it to the target destination. Simply put, when a user sends an email to another computer, it requests the mail server to deliver it to the intended recipient. Mail servers rely on several software modules that allow emails to be sent, received, retrieved, and forwarded.
3. Application server: An application server provides an environment that helps develop, process, and run web-based applications, irrespective of their functionality. The server executes computer programs or scripts essential for running PHP, Java, or .Net applications. Application servers are much like web servers as they tend to use HTTP protocol and answer client requests. However, these servers focus on creating dynamic websites that use object pooling, messaging services, and others; for example, ecommerce websites, blogs, etc. On the other hand, web servers are inclined towards creating static websites where information remains the same, for example, technical documentation websites, corporate portfolio websites, read-only websites, landing pages, and so on. In some cases, application servers include a web server component in them so that they can perform the function of a web server when needed.
4. Database server: Database servers offer database services to client computers. Users can access, modify, store, and retrieve data from a database by executing a query; for example, an SQL query. Database servers are responsible for handling the security and recovery of database management systems (DBMS). They store digital files, application files, and non-database files. Large organizations use these servers to safeguard their sensitive and valuable corporate data. Some examples of database servers include Microsoft SQL, MySQL, MongoDB, and SQLite.
5. DNS server: DNS servers are domain name servers. These computers resolve server names that reside in a network. DNS servers are an integral part of the internet as they translate user-understandable URLs into their corresponding IP addresses.
6. Proxy server: A proxy server acts as an intermediary between local networks and worldwide networks. It provides a communication interface between interacting networks by accepting requests from one network and forwarding them using its own IP address. These servers cache frequently accessed web pages, which helps faster loading when accessed in the future. As a result, the network’s bandwidth is reduced significantly. Moreover, proxy servers filter network communication and are always available, which is crucial for network load balancing. These servers also keep clients anonymous as their original IP address is replaced with a proxy.
7. DHCP server: Dynamic host configuration protocol servers refer to computer systems that dynamically assign IP addresses to clients. The advantage of this automatic process is that it minimizes the errors that manual handling may bring along, such as typo errors or IP conflicts. DHCP servers maintain configuration updates of network devices; for example, they update or change expired IP addresses or manage the IP addresses of devices that move from location to location. These servers also play a key role in network administration since they can simultaneously address multiple client requests.
8. File server: A file server refers to a machine that provides shareable disks that can be accessed by the workstations on a network. The disk holds computer files such as text files, images, graphic files, audio & video files, and so on. File servers are typically used for storage purposes. Hence, they neither run computer programs nor perform computational tasks. File servers use different protocols to access files depending on the computing environment. For example, internet file servers are accessible via FTP and HTTP protocols, while file servers on LAN, such as the ones used in offices and schools, are accessed using SMB or NFS protocol.
9. Gaming server: Gaming servers connect the global online gaming community. They support multiplayer games such as Counter-Strike, Minecraft, etc. Moreover, these servers manage player and game data while synchronizing player activity in the virtual world.
10. Print server: Print servers connect printing devices to clients on a network. They accept print tasks from users and queue them in anticipation that printers can fail to cope with the number of requests received in a certain timeframe. These servers use different protocols to accomplish print jobs, such as Internet Printing Protocol.
Key Features of Servers
Servers are key to organizations because they enhance the capabilities of a network by offering features such as scalability, efficiency, and business continuity to enterprise networks. While servers are critical for all businesses, the following are some of their fundamental features.
1. Scalability: As businesses expand, the demand for new machines, disk space upgrades, faster speeds, and better control over remote access keeps growing in the networking environment. However, it is worthwhile to note that this system requirement has to be met without replacing older machines. This ensures businesses run smoothly even while updating the client-server architecture. Servers play a critical role in such situations since they are not only capable of supporting the increasing number of clients but also managing dynamic workloads and upgrades.
2. High processing power: Servers provide high processing power to underlying clients as the available compute resources add up in the client-server framework. As a result, networks can handle an increasing number of jobs without impacting performance.
3. Reliability: Servers ensure that critical computing systems are always available and online, ensuring zero downtime for businesses. When any network device or component fails, it can impact the company’s business. However, as a client-server setup has multiple devices within a network, the jobs of failed components are taken up by backup devices. Such an arrangement guarantees seamless network connectivity. Additionally, where there is less load on the network, administrative teams can shut down some idle servers to cut down energy waste.
4. Better collaboration: Unlike standalone systems, servers drive collaboration because professionals and computers can easily access shared network resources, computer programs, and devices.
5. Cost savings: As servers manage a lot of network workload, the overall stress on individual network devices is reduced. As a result, devices showcase good performance throughout without much maintenance, saving companies from additional expenses.
6. Safeguard from cyberattacks: Servers play an important role in protecting network devices or websites from external attacks. For every data request received from the client, the IP address is verified to evaluate its authenticity. If the request shows signs of suspicious behaviour, such as in malware attacks or DDoS attacks, the server can deny it and directly block the client’s IP address as a safety measure. These are a few key features that are distinct from traditional server functions, such as serving user requests, storing data, providing a database to run computational tasks, and managing file transfers. Owing to these benefits, the demand for server architecture has risen globally in recent years.
