A computer network is a group of computers connected to each other through a medium like wires, optical fiber, or any wireless medium so that these computers can interact with each other through a network. The ambition of computer networks is to share resources and information with each other.
Uses of computer networks
- Resource sharing
- Simultaneous access
- High reliability because of alternative sources of data
- Cost reduction
- Connection medium
The main purpose of computer networking is resource sharing. Resource sharing means creating all programs, peripheral devices, and data accessible to anyone computer on the network to all other computers without thinking about the physical area. So a user at a distance can share the resources and see computer data in a similar way that a local user uses them.
We can put some data on a computer and access that data or information from different computers at a time. We use this feature of the network every day. We access Google simultaneously and Google has a server computer that has the data that we access.
High Reliability because of alternative sources of data
For example, we have multiple servers of Wikipedia where we read articles. So if one of these servers goes down then another server will take the role of that server. This thing makes computer networks reliable.
Or another example is that we make backup online for every data of my computer. If someday my computer goes crashes, I can download that online backup and do the recovery easily.
If there are multiple computers in an office and one printer is connected to the network then every computer can print pages from that printer. So the cost of multiple printers will be reduced.
A computer network creates a connection medium between computers that can share resources and information. It can connect even if you are in another country.
Criteria for a Data Communication Network
There are a lot of criteria to make a good data communication network. But there 3 basic criteria that are most important:
Performance means the rate of transferring error-free data on a network. The second thing we see in performance is the speed of data transmission.
Reliability is the degree of the network’s trustworthiness, consistency, and dependability. Reliability is the measure of how much a network is usable. MTBF (Mean Time Between Failure) is a measurement of the average time a network device is expected to work between failures.
It is a measurement of how a network secures data from failure and attacks. Security is the protection of Hardware, software, and data from unauthorized access.