What is it called when computers are linked together to share information?
As networking needs evolved, so did the computer network types that serve those needs. Here are the most common and widely used computer network types:
Important terms and concepts
The following are some common terms to know when discussing computer networking:
Examples of computer networks
The wired or wireless connection of two or more computers for the purpose of sharing data and resources form a computer network. Today, nearly every digital device belongs to a computer network.
In an office setting, you and your colleagues may share access to a printer or to a group messaging system. The computing network that allows this is likely a LAN or local area network that permits your department to share resources.
A city government might manage a city-wide network of surveillance cameras that monitor traffic flow and incidents. This network would be part of a MAN or metropolitan area network that allows city emergency personnel to respond to traffic accidents, advise drivers of alternate travel routes, and even send traffic tickets to drivers who run red lights.
The Weather Company worked to create a peer-to-peer mesh network that allows mobile devices to communicate directly with other mobile devices without requiring WiFi or cellular connectivity. The Mesh Network Alerts project allows the delivery of life-saving weather information to billions of people, even without an internet connection.
Computer networks and the internet
The internet is actually a network of networks that connects billions of digital devices worldwide. Standard protocols allow communication between these devices. Those protocols include hypertext transfer protocol (the ‘http’ in front of all website addresses). Internet protocol (or IP addresses) are the unique identifying numbers required of every device that accesses the internet. IP addresses are comparable to your mailing address, providing unique location information so that information can be delivered correctly.
Internet Service Providers (ISPs) and Network Service Providers (NSPs) provide the infrastructure that allows the transmission of packets of data or information over the internet. Every bit of information sent over the internet doesn’t go to every device connected to the internet. It’s the combination of protocols and infrastructure that tells information exactly where to go.
How do they work?
Computer networks connect nodes like computers, routers, and switches using cables, fiber optics, or wireless signals. These connections allow devices in a network to communicate and share information and resources.
Networks follow protocols, which define how communications are sent and received. These protocols allow devices to communicate. Each device on a network uses an Internet Protocol or IP address, a string of numbers that uniquely identifies a device and allows other devices to recognize it.
Routers are virtual or physical devices that facilitate communications between different networks. Routers analyze information to determine the best way for data to reach its ultimate destination. Switches connect devices and manage node-to-node communication inside a network, ensuring that bundles of information traveling across the network reach their ultimate destination.
Computer network architecture defines the physical and logical framework of a computer network. It outlines how computers are organized in the network and what tasks are assigned to those computers. Network architecture components include hardware, software, transmission media (wired or wireless), network topology, and communications protocols.
Main types of network architecture
There are two types of network architecture: peer-to-peer (P2P) and client/server. In P2P architecture, two or more computers are connected as “peers,” meaning they have equal power and privileges on the network. A P2P network does not require a central server for coordination. Instead, each computer on the network acts as both a client (a computer that needs to access a service) and a server (a computer that serves the needs of the client accessing a service). Each peer makes some of its resources available to the network, sharing storage, memory, bandwidth, and processing power.
In a client/server network, a central server or group of servers manage resources and deliver services to client devices in the network. The clients in the network communicate with other clients through the server. Unlike the P2P model, clients in a client/server architecture don’t share their resources. This architecture type is sometimes called a tiered model because it's designed with multiple levels or tiers.
Network topology refers to how the nodes and links in a network are arranged. A network node is a device that can send, receive, store, or forward data. A network link connects nodes and may be either cabled or wireless links.
Understanding topology types provides the basis for building a successful network. There are a number of topologies but the most common are bus, ring, star, and mesh:
Computer network security protects the integrity of information contained by a network and controls who access that information. Network security policies balance the need to provide service to users with the need to control access to information.
There are many entry points to a network. These entry points include the hardware and software that comprise the network itself as well as the devices used to access the network, like computers, smartphones, and tablets. Because of these entry points, network security requires using several defense methods. Defenses may include firewalls—devices that monitor network traffic and prevent access to parts of the network based on security rules.
Processes for authenticating users with user IDs and passwords provide another layer of security. Security includes isolating network data so that proprietary or personal information is harder to access than less critical information. Other network security measures include ensuring hardware and software updates and patches are performed regularly, educating network users about their role in security processes, and staying aware of external threats executed by hackers and other malicious actors. Network threats constantly evolve, which makes network security a never-ending process.
The use of public cloud also requires updates to security procedures to ensure continued safety and access. A secure cloud demands a secure underlying network.
Read about the top five considerations (PDF, 298 KB) for securing the public cloud.
As noted above, a mesh network is a topology type in which the nodes of a computer network connect to as many other nodes as possible. In this topology, nodes cooperate to efficiently route data to its destination. This topology provides greater fault tolerance because if one node fails, there are many other nodes that can transmit data. Mesh networks self-configure and self-organize, searching for the fastest, most reliable path on which to send information.
Type of mesh networks
There are two types of mesh networks—full mesh and partial mesh:
Load balancers and networks
Load balancers efficiently distribute tasks, workloads, and network traffic across available servers. Think of load balancers like air traffic control at an airport. The load balancer observes all traffic coming into a network and directs it toward the router or server best equipped to manage it. The objectives of load balancing are to avoid resource overload, optimize available resources, improve response times, and maximize throughput.
For a complete overview of load balancers, see Load Balancing: A Complete Guide.
Content delivery networks
A content delivery network (CDN) is a distributed server network that delivers temporarily stored, or cached, copies of website content to users based on the user’s geographic location. A CDN stores this content in distributed locations and serves it to users as a way to reduce the distance between your website visitors and your website server. Having cached content closer to your end users allows you to serve content faster and helps websites better reach a global audience. CDNs protect against traffic surges, reduce latency, decrease bandwidth consumption, accelerate load times, and lessen the impact of hacks and attacks by introducing a layer between the end user and your website infrastructure.
Live-streaming media, on-demand media, gaming companies, application creators, e-commerce sites—as digital consumption increases, more content owners turn to CDNs to better serve content consumers.