Introduction to Computer Networking and Hardware

Interested in becoming a computer networking technician? Learn the basics of computer networking and hardware infrastructure and decide whether a career as a computer networking technician is right for you.

What Is a Computer Network?

In its simplest form, a computer network is a system of one or more interconnected computer systems that share resources. Different hardware and software components, technologies, and configurations form a network.

The Internet

The internet is the network of all networks. It consists of millions of interconnected individual computers, as well as computer networks across the entire world. The internet uses standard network protocols (TCP/IP) for communication, and being in the public domain, is free for all users.

Types of Networks

Computer networks can be classified in different ways. One way of classifying networks is by geographical distance between the different components.

In a local area network (LAN), the component systems are in close proximity, perhaps within a room or building, while a metropolitan area network (MAN) is spread out over a larger distance, like a town, city, or university campus.

MANs are comprised of interconnected, smaller LANs and are likely to be slower and less secure than LANs. When the network spreads out over a very large distance across different cities, it is necessary to connect several smaller LANs into a wide area network (WAN). An example of an enterprise WAN might be a network connecting the company’s main office and the branch offices, while sharing services like cloud storage.

Another way of classifying networks is designating them as open networks or closed networks. Open networks do not close upon themselves and connect to the internet, while closed networks are connected only to each other and do not have any external download or upload source. Closed networks can usually be found within a home or small office.

Within a network, all computers can have equal processing power and share all resources as in a peer-to-peer network. It can also have dedicated computers called servers and have the rest of the less powerful computers on the network connect to the server in a client/server configuration. The servers perform the bulk of processing and service applications, like email systems and network storage drives, while the clients connect to the server and utilize its services.

A special type of network is a virtual private network (VPN) formed when a computer connects to a trusted network from an external location, usually through the internet. This type of network is common in the corporate environment where employees might need to connect to the protected office network from their homes.

Network Infrastructure

The term “network infrastructure” refers to all the different components that go into building a computer network. Hardware refers to the actual physical parts used in building a network.

A network uses cables to connect the different devices (for a wired network) and junction boxes like routers, switches, and gateways. Network address cards are usually part of the connecting device, although sometimes a terminal adapter might be necessary to connect.

Software, unlike hardware, does not have any physical components but is compromised of programs that run on the hardware. Software performs functions like testing a network, monitoring and controlling a network, and securing a network from intrusions and malware. The operating system needs to be compatible with the kind of network it is connected to.

Also, networking infrastructure must take into account the many services that a network uses. Each computer on the network needs a unique identifier called an IP address, and network protocols help communicate on the network. Many different functions like email management, file transfers, and cloud services all use different protocols and communication methods, all of which must be compatible with the network.

Network Protocols

Computer systems communicate with each other and resources using network protocols. Most networks use multiple protocols.

One of the most common, used with the internet and many other networks, is TCP/IP. Some of the other protocols are FTP for file transfers, HTTP for connecting to locations on the World Wide Web, and HTTPS which is a secure version of HTTP.

Network Topologies

A network is a system of interconnected links (connections) and nodes (devices). These links and nodes arrange in various topologies or a combination of the same.

In the bus topology, there is one main link and all nodes connect to this link. This is the most common kind of topology used in small networks in the home or office.

The ring topology takes the form of a loop that closes on itself, and all devices are connected to this loop.

When there is a central hub and all other devices connect to this hub, this is called a star topology. The central hub could be a source of bottlenecks since all devices connect to it.

In the tree topology, devices are connected in a star configuration and then linked using a bus to form the tree topology.

Wired Versus Wireless Networking

Today, with the exponential increase in mobile computing, more and more networks communicate without physical cables. Instead, they use radio waves and additional technologies like WiFi or 5G to connect to the internet and other networks.

Wireless networks are convenient because they allow users to connect from anyplace, like an airport or neighborhood coffee shop, but wired networks are more reliable and can be faster than wireless networks.

Designing a Computer Network

Designing a computer network is challenging because of the different hardware and software components involved, as well as the different options for topologies and configurations. However, the network should take into consideration the needs and requirements of the users and cost of network infrastructure and building and maintaining the network.

Security issues must be considered, including the cost of keeping the network free from intrusions and malware.

The network must have some inbuilt redundancy to account for downtime and breakdowns. However, it should be flexible enough to allow for expansion and growth.

Managing the network and keeping it running efficiently is usually done by using network management software, and this is a factor that must also be addressed.

Selecting Computer Network Components

When building a network, there are many choices in the different components of the networking infrastructure. Depending upon the network design, the components must be carefully chosen.

If it is a wired network, then cables will connect the different parts together. There are two main types of cables—coaxial (coax) and twisted pair.

The coax cables are the most common, and they carry a terminator at the end that allows for a connection to another device. The twisted pair cables are cheaper than coax cables and need a switch to be able to connect the different devices.

In a wireless configuration, cables are not necessary, but a router is required to broadcast the outgoing signal and receive the incoming signal from the wireless network.

There are many different types of routers available on the market. The most important factor in selecting a router is bandwidth or how much data flows in and out of the router. Routers can only connect networks using the same communication protocols.

If connecting two dissimilar networks together, instead of a router, a device called a gateway is used. Any device on the network like a computer or printer needs an inbuilt network card before it can connect successfully to the network. If a network interface is not present, an external adapter will have to be used.

Network Security and Preserving Integrity

One of the major tasks in computer networking is maintaining the network after creation. Networks are subject to both internal, as well as external, attacks. Malicious software can bring a network down very fast, possibly compromising sensitive data as well as affecting productivity of users.

Some of the common types of malware encountered by network administrators are different kinds of viruses which take up residence in host computers and replicate, eating up processing power and memory; Trojan horses which hide within a valid program and slowly destroy the computer system; and spamming, where computers are bombarded with unwanted data.

Network security prevents this unauthorized access. Software tools can check the network regularly, determining if any data have been compromised or if there has been any kind of network intrusion.

Network Security Using Firewalls

A firewall is a commonly used term in computer networking and refers to a network security system (either hardware or software) that enforces security rules regarding incoming and outgoing traffic. It allows only authorized data to pass while denying access to unauthorized data.

Firewalls are of different types, and they filter the network traffic based on different methods.

There is the application-layer firewall that works at a very low level (on the network protocol stack) and filters out unauthorized packets of data.

Sometimes a firewall takes the form of a dedicated computer running special software and acts as a proxy server. The proxy server acts as a buffer between the trusted network and the untrusted network, like the internet. If any threats come in from the outside, they will reach the proxy server first before reaching the trusted network and before any further damage is done.

Most firewalls use a mechanism called network address translation (NAT) in which the addresses of the computers on the trusted network are hidden by the firewall and are not detectable outside the network.

Network Support and Maintenance

Once a computer networking technician installs a network that is secure, network administrators need to maintain the network to ensure smooth functioning. Some of the routine maintenance tasks that need to be performed by the computer networking technician include these.

  • Maintaining current versions of software and hardware
  • Ensuring all devices are functioning optimally and detecting malware attacks
  • Maintaining documentation and records relating to the network
  • Properly designing future extensions to the network
  • Backing up data and restoring data from backups as necessary
  • Troubleshooting any reported malfunctions

Interested in learning more about computer networking hardware infrastructure? Ready to become a computer networking technician?

The Computer Technician Networking Specialist program at Hunter Business School is designed to prepare computer networking students for entry-level positions in the fields of electronics, computer technology, and networking. Students build their own computers and use them in the learning process.

Contact us today to find out more about how to become a computer networking technician on Long Island.

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