What is computer networking? Everything you need to know

Computer networking definition

Computer networking is a system of connected computers or devices that share data and network resources. The computers and devices on the network use standardized network protocols (communications) to exchange data with any other device on the network. These protocols are defined by the Open Systems Interconnection or OSI model.

How does computer networking work?

Computer networking works via a system of nodes and links that make up the basic architecture of the network. A node is just a technical term for a device, such as a computer or a router, that is part of the network. A link is the physical or wireless connections that make up the lines of communication within the network.

Data communication equipment (DCE) refers to nodes like modems, hubs, and switches that handle communications. Nodes like computers, printers, and terminals are called data terminal equipment (DTE).

Despite the many different nodes and equipment on a network, they all communicate via a standardized protocol defined by the OSI model. These protocols are essential to the network’s functioning and allow various devices to be easily and quickly connected to it.

HTTP, TCP/IP, and DHCP are common protocols you may be familiar with. The OSI model consists of seven layers, each of which can use one of these types of protocols.

For an example of how all of these terms work, let’s say you connect your laptop to a work or school network to access a printer. Your laptop and the printer are both nodes (DTE) on the network. If you connect via Wi-Fi, the Wi-Fi signal is the link.

The various network switches and hubs that manage the communication between your laptop and printer are also nodes (DCE) on the network. You can think of the standardized communication protocols (OSI model) as the language the devices use to talk to each other.

What do computer networks do?

Computer networks can serve many functions, but they are all related to secure communication and data sharing among devices.

In some cases, many different people use a computer network to easily access the same data, such as at a company. The network allows workers to share and access the same files for collaboration.

You may use another type of computer network to share network resources, such as a computer network that allows users to share internet access and printers.

A network can also combine all these functions and include others, depending on the user’s needs and the network’s construction.

Key components of a computer network

In any computer network, various key components enable communication and data sharing among connected devices.

• Network devices (nodes). As mentioned, these are devices such as computers or printers connected directly to the computer network. When you connect your computer to a work or school network, the network recognizes your computer as a network device.
• Switch. A switch is a type of DCE node. A switch handles the communications between the network devices. Network communications are broken into small segments known as packets. The switch manages these packets so they reach their intended destination.
• Router. A router is also a type of DCE node. A router connects the different switches. You can use a router to create larger networks or connect separate networks. For example, a router would connect your small business computer network to the internet.
• Servers. Specialized computers known as servers store data or run applications. Network devices like laptop computers can access these servers to share data. Not all networks require a server, such as with some smaller networks or peer-to-peer (P2P) networks.

What is network topology?

Network topology determines the arrangement of network devices. Think of network topology as the blueprint for constructing and laying out the network. Different topologies offer unique properties based on the network’s requirements.

• Ring topology. In ring topology, each device connects with two other devices. This type of linking creates a ring shape. Data can move in both directions around the ring. However, if a node fails, communications can’t travel past that node, which could cause the network to fail.
• Bus topology. With bus topology, every node connects to a single data cable called the bus. Data travels along the bus, and every node receives the same signal. A failure of one node will not interrupt the flow of information in a bus topology.
• Star topology. In a star topology, nodes are connected to a central server or device. The benefit of a star topology is that each node can send and receive its requests independently. This process allows data to flow more efficiently along the individual network connections.
• Mesh topology. A mesh topology uses many different connections between various devices to create ways for data to flow between nodes. The overall topology is decentralized, so the failure of one device doesn’t impact the rest of the network. A mesh network can also find the most efficient route for data and information instead of relying on a specific path.

What are the types of computer networking?

Computer networking is a deep and complex topic. Many different types of computer networks are in use. However, a majority of networks fall into four main categories.

Local area networks (LAN)

A local area network (LAN) is limited by geographic location. These networks generally cover one specific area, such as a small office or building. Most small businesses will use a LAN for networking purposes within their office.

Network engineers can also use LANs for testing purposes before rolling out changes to a larger network.

Although LANs are small networks, they can still connect to larger networks, such as the internet. This feature allows users on the LAN to all share the same internet connection.

Wide area network (WAN)

A wide area network (WAN) is a type of enterprise computer networking used by large organizations. It covers large geographical areas and connects networks and resources across towns, states, or countries. WANs specialize in high-speed data transmission and security over long distances.

A WAN generally connects smaller LANs, but it can connect virtually any network across distances.

A newer type of WAN is an SD-WAN or software-defined WAN. An SD-WAN replaces many hardware WAN components traditionally used to manage optimization. The software allows for the virtualization of network resources so optimizations can be done in real time. Network engineers can also use an SD-WAN to create faster and more efficient networks they manage from a centralized location.

Cloud networks

Cloud networks are another popular type of network for enterprise use. They differ from a typical LAN or WAN in that they are entirely hosted on private or public cloud servers.

Instead of managing network resources on-premise, such as at an office, dedicated cloud facilities manage these resources. These third-party cloud service providers handle the maintenance and other aspects of the network. This process allows users and businesses to focus on developing for speed and functionality without focusing on infrastructure maintenance.

One of the most significant benefits of cloud networking is the ability to scale network resources as needed.

In a cloud network, you can instantly procure new server capacity during heavy use through software automation. With a typical LAN at a business, if a new physical server is needed, the process of adding a new one can take days or even weeks. Cloud network scaling allows businesses to be agile and quickly respond to demands.

Cloud networks can also be part of a hybrid network. So a LAN or WAN can have some resources managed in a cloud network while certain functions are still performed locally.

Service provider networks

Service provider networks are the backbone of most WANs and other networks. They provide the core transmission functions and handle large bandwidth applications. Examples of service provider computer networking include large telecommunication companies, internet service providers, and data carriers.

Service provider networks can offer both wired and wireless computer networking uses. They can also supply internet access for smaller applications, such as home use or small business.

What are the types of computer network architecture?

There are variations in network architecture, but there are two main categories — client-server architecture and peer-to-peer architecture.

Client-server architecture

With this architecture, network computer nodes behave as clients or servers.

A server stores data or performs other centralized functions. For example, a server may store documents that different clients can access and share. Another type of server is a DNS server, which redirects website requests to the proper web address.

A server can also run applications or software. An example of this is a mail server in an enterprise setting. The mail server runs a specific mail software program, and the different client computers access their mail via that server.

One important aspect of client-server architecture is that all client requests go through a server. Different clients do not interact with each other or share data directly.

For example, if two employees work on a common document, the server stores the document, and both employees access the same file. The employees do not share the file directly with each other.

Peer-to-peer architecture

In peer-to-peer (P2P) networks, nodes can be clients and servers. Nodes can also have identical privileges.

With P2P networks, clients share resources and data directly with each other, and requests do not need to go through a server. Processing power and memory resources are also shareable between clients in a P2P network.

P2P networks are also sometimes referred to as decentralized because no central server is receiving requests and handling traffic between clients.

Many file-sharing networks utilize P2P architecture. The benefits are that no central servers need to store files, and the network self-adjusts depending on the demand and the number of users.

Content delivery and distributed computing power are other common examples of P2P architecture.

Computer network security threats and solutions

For a computer network to offer benefits, it must offer fast and efficient connections for its users to share resources and data. However, cybersecurity must also be a top priority to protect data and network resources. Networks need sophisticated defense measures to combat advanced attack methods such as computer network operations and smaller attacks by individuals.

Firewalls

A firewall monitors traffic into and out of a computer network. It then uses a set of predetermined rules to decide whether to allow the traffic or block it for security reasons.

Access control

Access control is a set of policies and tools that restrict or allow access to network resources. Access control protocols can also quarantine certain users, data, or devices based on risk factors.

Basic access control starts with simple passwords and login credentials. However, more advanced access control involves endpoint device management and zero-trust architecture techniques.

Network segmentation

Network segmentation uses software to segment different parts of the network. Each segment then has its own security and access controls. This feature allows security and network engineers to tailor the requirements depending on the specific risk level and other factors.

Wireless security

Computer networks that utilize wireless connections require special encryption since the signal is open for virtually anyone to capture.

Wireless computer networks need to encrypt data as it travels in both directions to maintain network security and prevent computer network exploitation.

Intrusion prevention systems

Intrusion prevention systems (IPSs) continually monitor network activity and search for unauthorized attempts to access network resources. IPS tools can either be software based or hardware based.

When an IPS detects an intrusion attempt, it can block the attempt and log details about the intrusion. Other cybersecurity tools can use these details to make risk assessments and threat detection more accurate.