Let's start with the basics: What exactly is a network?

Table of Contents

• Need for Computer Networks
• Components of a network
• Advantages of Computer Networks
• Disadvantages of Computer Networks
• Network Criteria
• Performance
• Reliability
• Security

A computer network is like a team of connected computers and devices that talk to each other using a common language. They share stuff, like sending and getting data, over a network, which is like a virtual highway for information.

When computers or devices can talk and exchange info, we say they are " interconnected ." Each computer or device is called a "node," and anything that can send or receive data can be a node too. They talk through " communication links ," which are like the roads connecting them.

The main reason for having a computer network is to share things. Nowadays, most networks share a link to the internet, but they can also share things like printers or file servers.

Need for Computer Networks

The important motivations for a computer network include the following.

• Sharing of resources such as printers and expensive software and databases.
• Serves as communication media for long-distance communication
• Provides high reliability and availability of data and information among the users of the network.
• Provides economy of data storage and communication
• Scalable to accommodate an increasing number of users
• Offers centralized administration
• Connects people, buildings, and organizations

 

Components of a network

 Following are some of the major components of a computer network.

1. Computers or workstations
2. Servers such as File Servers, Print Servers, Database Servers etc.
3. Printers, Faxes
4. Interconnecting devices such as switches, hubs, routers, bridges, gateways, etc.
5. Connectors, cables(coaxial, twisted pair or fiber optic)
6. A Network Interface Card (NIC) in each computer
7. Network Operating Systems

 

Advantages of Computer Networks

Following are some of the advantages of a computer network

1. Increased Speed: The network provides the fastest medium of data communication
2. Reduced Cost: It reduces the storage maintenance and data transfer cost per unit.
3. Improved Security: It is now possible to protect the programs and files from illegal access.
4. Centralized Administration: A centralized server can store important software and provide controlled access to many users.
5. Flexible Access: The authorized user can access their files from any computer connected to the network.

Disadvantages of Computer Networks

The major disadvantages of a computer network are as follows:

1. High cost of installation: The initial cost of installation of a computer network is high.
2. Maintenance cost: It requires proper and careful administration and maintenance by a specialized technical person.
3. Failure of Server: If the file server goes down then the entire network comes to stand standstill.
4. Cable fault: The computers in the network are connected with the help of cables. If the backbone cable fails it causes the entire network failure.
    

Network Criteria

The most important criteria for a network to be efficient are performance reliability and security.

Performance

• The performance of a network can be measured in many ways including transit time and response time.
• Transit time is the amount of time required to transmit a message from one device to the other.
• Response time is the time elapsed between a request and a response.
• The performance of a network can be ensured by achieving higher throughput and smaller delay times.
• The performance of a network also depends on other factors including the following.
  1. Number of users
  2. Type of transmission medium
  3. Network hardware and software.

 

Reliability

The reliability of a network depends on accuracy, frequency of failure, the time it takes to recover from failure, and robustness in a catastrophe. A computer network is said to be reliable if it provides a higher level of accuracy, less frequency of failure, less recovery time, and robust to catastrophic failure.

Security

Network Security issues include protecting data from unauthorized access, viruses, and different types of attacks to access network resources.

The network protocols provide security mechanisms to ensure the protection of data from unauthorized access. A good network is protected from viruses by specifically designed hardware and software.